View source for Sinusitis

{{cs1 config|name-list-style=vanc|display-authors=6}}{{Infobox medical condition (new)
| name = Rhinosinusitis
| synonyms = Sinus infection, sinusitis, chronic rhinosinusitis without nasal polyps, chronic rhinosinusitis with nasal polyps
| image = Sinusitis cdc.png
| caption = An illustration showing the difference between healthy sinuses and diseased sinuses
| image2 =
| field = [[Otorhinolaryngology]]
| symptoms = [[nasal discharge]], [[nasal blockage]], [[facial pain]], reduction or loss of smell, [[fever]]<ref name="pmid25833927"/><ref name="pmid27113482"/>
| onset =
| duration =
| causes = [[Infection]] (bacterial, fungal, viral), [[allergy|allergies]], [[air pollution]], structural problems in the nose<ref name="cdc.gov-20132" />
| risks = [[Asthma]], [[cystic fibrosis]], [[immunodeficiency|poor immune function]]<ref name="pmid25833927"/>
| diagnosis = Usually based on symptoms
| differential = [[common cold]], [[rhinitis]], [[upper respiratory infection]], [[temporomandibular joint disorder]], [[tension headache]], [[vascular headache]], [[dental infection]]
| prevention = handwashing, vaccinations, avoiding smoking<ref name="cdc.gov-20132" />
| treatment = [[Analgesics|Pain medications]], [[nasal steroid]]s, [[nasal irrigation]], [[antibiotic]]<ref name="pmid25833927"/><ref name="pmid25892369"/>
| medication =
| prognosis =
| frequency = 10–30% each year (developed world)<ref name="pmid25833927"/><ref name="Adkinson-2014"/>
| deaths =
| complications =
}}<!-- Definition and symptoms -->
'''Sinusitis''', also known as '''rhinosinusitis''' and commonly known as a '''sinus infection''', is an [[inflammation]] of the [[Nasal mucosa|mucous membranes]] that line the [[Paranasal sinuses|sinuses]] resulting in symptoms that may include production of thick [[Mucus#Respiratory system|nasal mucus]], [[nasal congestion]], facial congestion, [[Orofacial pain|facial pain]], facial pressure, [[Hyposmia|loss of smell]], or [[fever]].<ref name="pmid258339273">{{cite journal |vauthors=Rosenfeld RM, Piccirillo JF, Chandrasekhar SS, Brook I, Kumar KA, Kramper M, Orlandi RR, Palmer JN, Patel ZM, Peters A, Walsh SA, Corrigan MD |date=April 2015 |title=Clinical practice guideline (update): Adult Sinusitis Executive Summary |journal=Otolaryngology–Head and Neck Surgery |volume=152 |issue=4 |pages=598–609 |doi=10.1177/0194599815574247 |pmid=25833927 |s2cid=206469424 |doi-access=free}}</ref>'''<ref name="pmid27113482">{{cite journal |vauthors=Head K, Chong LY, Piromchai P, Hopkins C, Philpott C, Schilder AG, Burton MJ |date=April 2016 |title=Systemic and topical antibiotics for chronic rhinosinusitis |url=http://discovery.ucl.ac.uk/1489913/1/Schilder_Head_et_al-2016-The_Cochrane_library.pdf |url-status=live |journal=The Cochrane Database of Systematic Reviews |volume=2016 |issue=4 |doi=10.1002/14651858.CD011994.pub2 |pmc=8763400 |pmid=27113482 |s2cid=205210696 |archive-url=https://web.archive.org/web/20180722030626/http://discovery.ucl.ac.uk/1489913/1/Schilder_Head_et_al-2016-The_Cochrane_library.pdf |archive-date=2018-07-22 |access-date=2019-09-17}}</ref>'''

<!-- Cause and diagnosis -->
Sinusitis is a condition that affects both children and adults. It is caused by a combination of environmental factors and a person's health factors.<ref>{{Citation |last1=Battisti |first1=Amanda S. |title=Sinusitis |date=2024 |work=StatPearls |url=https://www.ncbi.nlm.nih.gov/books/NBK470383/ |access-date=2024-11-12 |place=Treasure Island (FL) |publisher=StatPearls Publishing |pmid=29262090 |last2=Modi |first2=Pranav |last3=Pangia |first3=Jon |archive-date=2023-11-18 |archive-url=https://web.archive.org/web/20231118134212/http://www.ncbi.nlm.nih.gov/books/NBK470383/ |url-status=live }}</ref> It can occur in individuals with [[Allergy|allergies]], exposure to environmental irritants, structural abnormalities of the [[nasal cavity]] and [[Paranasal sinuses|sinuses]] and [[Immunodeficiency|poor immune function]].<ref name="Adkinson-20143">{{cite book |last1=Adkinson |first1=N. Franklin |url=https://books.google.com/books?id=vT9YAQAAQBAJ&pg=PA687 |title=Middleton's allergy: principles and practice |date=2014 |publisher=Elsevier Saunders |isbn=978-0-323-08593-9 |edition=Eight |location=Philadelphia |page=687 |archive-url=https://web.archive.org/web/20160603211855/https://books.google.com/books?id=vT9YAQAAQBAJ&pg=PA687 |archive-date=2016-06-03 |url-status=live}}</ref> Most cases are caused by a [[viral infection]].<ref name="cdc.gov-20132">{{cite web |date=September 30, 2013 |title=Sinus Infection (Sinusitis) |url=https://www.cdc.gov/getsmart/antibiotic-use/URI/sinus-infection.html |url-status=live |archive-url=https://web.archive.org/web/20150407181505/http://www.cdc.gov/getsmart/antibiotic-use/URI/sinus-infection.html |archive-date=7 April 2015 |access-date=6 April 2015 |website=cdc.gov}}</ref> Recurrent episodes are more likely in people with [[asthma]], [[cystic fibrosis]], and [[immunodeficiency]].<ref name="pmid258339275">{{cite journal |vauthors=Rosenfeld RM, Piccirillo JF, Chandrasekhar SS, Brook I, Kumar KA, Kramper M, Orlandi RR, Palmer JN, Patel ZM, Peters A, Walsh SA, Corrigan MD |date=April 2015 |title=Clinical practice guideline (update): Adult Sinusitis Executive Summary |journal=Otolaryngology–Head and Neck Surgery |volume=152 |issue=4 |pages=598–609 |doi=10.1177/0194599815574247 |pmid=25833927 |s2cid=206469424 |doi-access=free}}</ref>

The diagnosis of sinusitis is based on the symptoms and their duration along with signs of disease identified by [[Endoscopy|endoscopic]] and/or [[Radiology|radiologic]] criteria.<ref name="Adkinson-20142">{{cite book |last1=Adkinson |first1=N. Franklin |url=https://books.google.com/books?id=vT9YAQAAQBAJ&pg=PA687 |title=Middleton's allergy: principles and practice |date=2014 |publisher=Elsevier Saunders |isbn=978-0-323-08593-9 |edition=Eight |location=Philadelphia |page=687 |archive-url=https://web.archive.org/web/20160603211855/https://books.google.com/books?id=vT9YAQAAQBAJ&pg=PA687 |archive-date=2016-06-03 |url-status=live}}</ref> Sinusitis is classified into acute sinusitis, subacute sinusitis, and chronic sinusitis. In acute sinusitis, symptoms last for less than four weeks, and in subacute sinusitis, they last between 4 and 12 weeks. In chronic sinusitis, symptoms must be present for at least 12 weeks.<ref>{{Cite book |title=Middleton's allergy: principles and practice |date=2014 |publisher=Elsevier/Saunders |isbn=978-0-323-08593-9 |editor-last=Adkinson |editor-first=N. Franklin |edition=8th |location=Philadelphia, PA |editor-last2=Middleton |editor-first2=Elliott}}</ref> In the initial evaluation of sinusitis an [[otolaryngologist]], also known as an [[Ear, Nose and Throat|ear, nose and throat]] (ENT) doctor, may confirm sinusitis using  [[Endoscopy|nasal endoscopy]].<ref name="Adkinson-20142" /> Diagnostic imaging is not usually needed in the acute stage unless complications are suspected.<ref name="pmid258339274">{{cite journal |vauthors=Rosenfeld RM, Piccirillo JF, Chandrasekhar SS, Brook I, Kumar KA, Kramper M, Orlandi RR, Palmer JN, Patel ZM, Peters A, Walsh SA, Corrigan MD |date=April 2015 |title=Clinical practice guideline (update): Adult Sinusitis Executive Summary |journal=Otolaryngology–Head and Neck Surgery |volume=152 |issue=4 |pages=598–609 |doi=10.1177/0194599815574247 |pmid=25833927 |s2cid=206469424 |doi-access=free}}</ref> In chronic cases, confirmatory testing is recommended by use of [[computed tomography]].<ref name="pmid258339274" />

<!-- Prevention and treatment -->
Prevention of sinusitis focuses on regular [[hand washing]], staying up-to-date on [[Vaccination|vaccinations]], and avoiding [[smoking]].<ref name="cdc.gov-20133">{{cite web |date=September 30, 2013 |title=Sinus Infection (Sinusitis) |url=https://www.cdc.gov/getsmart/antibiotic-use/URI/sinus-infection.html |url-status=live |archive-url=https://web.archive.org/web/20150407181505/http://www.cdc.gov/getsmart/antibiotic-use/URI/sinus-infection.html |archive-date=7 April 2015 |access-date=6 April 2015 |website=cdc.gov}}</ref> [[Analgesics|Pain killers]] such as [[naproxen]], [[Nasal steroid|nasal steroids]], and [[nasal irrigation]] may be used to help with symptoms.<ref name="pmid258339276">{{cite journal |vauthors=Rosenfeld RM, Piccirillo JF, Chandrasekhar SS, Brook I, Kumar KA, Kramper M, Orlandi RR, Palmer JN, Patel ZM, Peters A, Walsh SA, Corrigan MD |date=April 2015 |title=Clinical practice guideline (update): Adult Sinusitis Executive Summary |journal=Otolaryngology–Head and Neck Surgery |volume=152 |issue=4 |pages=598–609 |doi=10.1177/0194599815574247 |pmid=25833927 |s2cid=206469424 |doi-access=free}}</ref><ref name="pmid258923692">{{cite journal |vauthors=King D, Mitchell B, Williams CP, Spurling GK |date=April 2015 |title=Saline nasal irrigation for acute upper respiratory tract infections |url=http://espace.library.uq.edu.au/view/UQ:201653/UQ201653_OA.pdf |url-status=live |journal=The Cochrane Database of Systematic Reviews |volume=2015 |issue=4 |doi=10.1002/14651858.CD006821.pub3 |pmc=9475221 |pmid=25892369 |archive-url=https://web.archive.org/web/20210829061619/https://espace.library.uq.edu.au/data/UQ_201653/UQ201653_OA.pdf?Expires=1630217866&Key-Pair-Id=APKAJKNBJ4MJBJNC6NLQ&Signature=fvzZFSRIkQZTLEhLp~QFYol~hVWVs5Yo2o0Vw3BhGOL7U3pmZx7K1xwMdix20C-ZBOBTDrFZyWfczpiMKk7xmMWYUsYU8tEF9SRghcv~x04vWlZkkUuL3E7OHRYrkCFawyesJkkEEQO5sQxtD0LLWuoQWlT7yRRWk4ZqrLeW7OCsFY5NhBYavteJhqCqtWifH5hIamsdfCYNZnVKx4mp66bQ5L5iozTDtmriPethrPxdoRvyPvYoPscI~ayOcvCjCjdYxsooSxLtw1KPpsbBbtEACOPp35YxrEPcON9XJO04wJeqpcy9FsRhJHM1Gg1-b8p5xUSx3LRrF42Dirskaw__ |archive-date=2021-08-29 |access-date=2018-04-20}}</ref> Recommended initial treatment for acute sinusitis is [[watchful waiting]].<ref name="pmid258339276" /> If symptoms do not improve in 7–10 days or worsen, then an [[antibiotic]] may be implemented or changed.<ref name="pmid258339276" /> In those in whom antibiotics are indicated, either [[amoxicillin]] or [[amoxicillin/clavulanate]] is recommended first line, with [[amoxicillin/clavulanate]] being superior to [[amoxicillin]] alone but with more side effects.<ref name="pmid332365252">{{cite journal |last1=Orlandi |first1=Richard R. |last2=Kingdom |first2=Todd T. |last3=Smith |first3=Timothy L. |last4=Bleier |first4=Benjamin |last5=DeConde |first5=Adam |last6=Luong |first6=Amber U. |last7=Poetker |first7=David M. |last8=Soler |first8=Zachary |last9=Welch |first9=Kevin C. |last10=Wise |first10=Sarah K. |last11=Adappa |first11=Nithin |last12=Alt |first12=Jeremiah A. |last13=Anselmo-Lima |first13=Wilma Terezinha |last14=Bachert |first14=Claus |last15=Baroody |first15=Fuad M. |year=2021 |title=International consensus statement on allergy and rhinology: rhinosinusitis 2021 |url=https://ueaeprints.uea.ac.uk/id/eprint/77501/1/Accepted_Manuscript.pdf |url-status=live |journal=International Forum of Allergy & Rhinology |publisher=Wiley |volume=11 |issue=3 |pages=213–739 |doi=10.1002/alr.22741 |issn=2042-6976 |pmid=33236525 |s2cid=227165628 |archive-url=https://web.archive.org/web/20230307191717/https://ueaeprints.uea.ac.uk/id/eprint/77501/1/Accepted_Manuscript.pdf |archive-date=2023-03-07 |access-date=2023-01-21 |last16=Batra |first16=Pete S. |last17=Bernal-Sprekelsen |first17=Manuel |last18=Beswick |first18=Daniel |last19=Bhattacharyya |first19=Neil |last20=Chandra |first20=Rakesh K. |last21=Chang |first21=Eugene H. |last22=Chiu |first22=Alexander |last23=Chowdhury |first23=Naweed |last24=Citardi |first24=Martin J. |last25=Cohen |first25=Noam A. |last26=Conley |first26=David B. |last27=DelGaudio |first27=John |last28=Desrosiers |first28=Martin |last29=Douglas |first29=Richard |last30=Eloy |first30=Jean Anderson |last31=Fokkens |first31=Wytske J. |last32=Gray |first32=Stacey T. |last33=Gudis |first33=David A. |last34=Hamilos |first34=Daniel L. |last35=Han |first35=Joseph K. |last36=Harvey |first36=Richard |last37=Hellings |first37=Peter |last38=Holbrook |first38=Eric H. |last39=Hopkins |first39=Claire |last40=Hwang |first40=Peter |last41=Javer |first41=Amin R. |last42=Jiang |first42=Rong-San |last43=Kennedy |first43=David |last44=Kern |first44=Robert |last45=Laidlaw |first45=Tanya |last46=Lal |first46=Devyani |last47=Lane |first47=Andrew |last48=Lee |first48=Heung-Man |last49=Lee |first49=Jivianne T. |last50=Levy |first50=Joshua M. |last51=Lin |first51=Sandra Y. |last52=Lund |first52=Valerie |last53=McMains |first53=Kevin C. |last54=Metson |first54=Ralph |last55=Mullol |first55=Joaquim |last56=Naclerio |first56=Robert |last57=Oakley |first57=Gretchen |last58=Otori |first58=Nobuyoshi |last59=Palmer |first59=James N. |last60=Parikh |first60=Sanjay R. |last61=Passali |first61=Desiderio |last62=Patel |first62=Zara |last63=Peters |first63=Anju |last64=Philpott |first64=Carl |last65=Psaltis |first65=Alkis J. |last66=Ramakrishnan |first66=Vijay R. |last67=Ramanathan |first67=Murugappan |last68=Roh |first68=Hwan-Jung |last69=Rudmik |first69=Luke |last70=Sacks |first70=Raymond |last71=Schlosser |first71=Rodney J. |last72=Sedaghat |first72=Ahmad R. |last73=Senior |first73=Brent A. |last74=Sindwani |first74=Raj |last75=Smith |first75=Kristine |last76=Snidvongs |first76=Kornkiat |last77=Stewart |first77=Michael |last78=Suh |first78=Jeffrey D. |last79=Tan |first79=Bruce K. |last80=Turner |first80=Justin H. |last81=Drunen |first81=Cornelis M. |last82=Voegels |first82=Richard |last83=Wang |first83=De Yun |last84=Woodworth |first84=Bradford A. |last85=Wormald |first85=Peter-John |last86=Wright |first86=Erin D. |last87=Yan |first87=Carol |last88=Zhang |first88=Luo |last89=Zhou |first89=Bing}}</ref><ref name="pmid258339276" /> Surgery may be recommended in those with chronic disease who have failed medical management.<ref>{{cite web |date=April 3, 2012 |title=How Is Sinusitis Treated |url=https://www.niaid.nih.gov/topics/sinusitis/Pages/treatment.aspx |archive-url=https://web.archive.org/web/20150405025201/http://www.niaid.nih.gov/topics/sinusitis/Pages/treatment.aspx |archive-date=5 April 2015 |access-date=6 April 2015}}</ref>

<!-- Epidemiology and society -->
Sinusitis is a common condition.<ref name="pmid258339272">{{cite journal |vauthors=Rosenfeld RM, Piccirillo JF, Chandrasekhar SS, Brook I, Kumar KA, Kramper M, Orlandi RR, Palmer JN, Patel ZM, Peters A, Walsh SA, Corrigan MD |date=April 2015 |title=Clinical practice guideline (update): Adult Sinusitis Executive Summary |journal=Otolaryngology–Head and Neck Surgery |volume=152 |issue=4 |pages=598–609 |doi=10.1177/0194599815574247 |pmid=25833927 |s2cid=206469424 |doi-access=free}}</ref> It affects between about 10 and 30 percent of people each year in the United States and Europe.<ref name="pmid258339272" /><ref name="Adkinson-2014">{{cite book |last1=Adkinson |first1=N. Franklin |url=https://books.google.com/books?id=vT9YAQAAQBAJ&pg=PA687 |title=Middleton's allergy: principles and practice |date=2014 |publisher=Elsevier Saunders |isbn=978-0-323-08593-9 |edition=Eight |location=Philadelphia |page=687 |archive-url=https://web.archive.org/web/20160603211855/https://books.google.com/books?id=vT9YAQAAQBAJ&pg=PA687 |archive-date=2016-06-03 |url-status=live}}</ref>  The management of sinusitis in the United States results in more than {{US$}}11 billion in costs.<ref name="pmid258339272" />
{{TOC limit}}

==Signs and symptoms==
Acute sinusitis can present as facial pain and tenderness that may worsen on standing up or bending over, headache, cough, bad breath, nasal congestion, ear pain, ear pressure or [[Rhinorrhea|nasal discharge]] that is usually green in color, and may contain [[pus]] or blood.<ref>{{Cite web |date=2025-03-12 |title=What Is a Sinus Infection? Symptoms, Causes, Diagnosis, Treatment, and Prevention |url=https://www.everydayhealth.com/sinus-infection/guide/ |access-date=2025-03-18 |website=EverydayHealth.com |language=en}}</ref>Dental pain can also occur. A way to distinguish between toothache and sinusitis is that sinusitis-related pain is usually worsened by tilting the head forward or performing the [[Valsalva maneuver]].<ref name="pmid24861778">{{cite journal |vauthors=Ferguson M |date=September 2014 |title=Rhinosinusitis in oral medicine and dentistry |journal=Australian Dental Journal |volume=59 |issue=3 |pages=289–95 |doi=10.1111/adj.12193 |pmid=24861778 |doi-access=free}}</ref><ref>{{Cite web |title=New York City Surgeon Discusses 10 Signs a Sinus Infection Can Be Serious |url=https://yourbuzzfeed.com/article/new-york-city-surgeon-discusses-10-signs-a-sinus-infection-can-be-serious-187721-1745268187721 |website=YourBuzzfeed |date=2024-09-12 |access-date=2025-10-07 |language=en}}</ref>

Chronic sinusitis presents with more subtle symptoms of nasal obstruction, with less fever and pain.<ref>{{Cite book |last=Pasha |first=Raza |title=Otolaryngology-Head and Neck Surgery: Clinical Reference Guide |publisher=Plural Publishing Inc. |year=2013 |isbn=978-1-59756-532-5 |edition=4th}}</ref> Symptoms include facial pain, [[headache]], night-time coughing, an increase in previously minor or controlled asthma symptoms, general [[malaise]], thick green or yellow nasal [[Rhinorrhea|discharge]], feeling of facial fullness or tightness that may worsen when bending over, dizziness, aching teeth, and [[Halitosis|bad breath]].<ref name="Radojicic2">{{cite web |last=Radojicic |first=Christine |title=Sinusitis |url=http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/allergy/rhino-sinusitis/ |url-status=live |archive-url=https://web.archive.org/web/20121114060719/http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/allergy/rhino-sinusitis/ |archive-date=November 14, 2012 |access-date=November 26, 2012 |work=Disease Management Project |publisher=[[Cleveland Clinic]]}}</ref> Often, chronic sinusitis can lead to [[anosmia]], the loss of the sense of [[Olfaction|smell]].<ref name="Radojicic2" />

A 2005 review suggested that most "sinus headaches" are migraines.<ref>{{cite journal |vauthors=Mehle ME, Schreiber CP |date=October 2005 |title=Sinus headache, migraine, and the otolaryngologist |journal=Otolaryngology–Head and Neck Surgery |volume=133 |issue=4 |pages=489–96 |doi=10.1016/j.otohns.2005.05.659 |pmid=16213917 |s2cid=40427174}}</ref> The confusion occurs in part because migraine involves activation of the [[trigeminal nerves]], which innervate both the sinus region and the [[meninges]] surrounding the brain. As a result, accurately determining the site from which the pain originates is difficult. People with migraines do not typically have the thick nasal discharge that is a common symptom of a sinus infection.<ref>{{cite journal |author1=Headache Classification Subcommittee of the International Headache Society |year=2004 |title=The International Classification of Headache Disorders: 2nd edition |journal=Cephalalgia |volume=24 |issue=Suppl 1 |pages=9–160 |doi=10.1111/j.1468-2982.2004.00653.x |pmid=14979299 |doi-access=free}}</ref>

===By location===
The four paired [[paranasal sinuses]] are the frontal, ethmoidal, maxillary, and sphenoidal sinuses. The [[Ethmoid sinus|ethmoidal sinuses]] are further subdivided into anterior and posterior ethmoid sinuses, the division of which is defined as the [[Ethmoid sinus#Groups of sinuses|basal lamella]] of the [[middle nasal concha]]. In addition to the severity of [[disease]], discussed below, sinusitis can be classified by the sinus cavity it affects:

* [[Maxillary sinus|Maxillary]] – may cause pain or pressure in the maxillary (cheek) region, often experienced as a toothache or headache.<ref name="pmid248617783">{{cite journal |vauthors=Ferguson M |date=September 2014 |title=Rhinosinusitis in oral medicine and dentistry |journal=Australian Dental Journal |volume=59 |issue=3 |pages=289–95 |doi=10.1111/adj.12193 |pmid=24861778 |doi-access=free}}</ref>
* [[Frontal sinus|Frontal]] – may cause pain or pressure in the frontal sinus cavity (above the eyes), often experienced as a headache, particularly in the forehead area.
* [[Ethmoid sinus|Ethmoidal]] – may cause pain or pressure pain between or behind the eyes,  along the sides of the upper nose ([[Canthus|medial canthi]]), and headaches.<ref name="Terézhalmy-20093">{{cite book |url=https://archive.org/details/physicalevaluati00tere |title=Physical evaluation in dental practice |vauthors=Terézhalmy GT, Huber MA, Jones AC, Noujeim M, Sankar V |publisher=Wiley-Blackwell |year=2009 |isbn=978-0-8138-2131-3 |location=Ames, Iowa |page=[https://archive.org/details/physicalevaluati00tere/page/n37 27] |url-access=limited}}</ref>
* [[Sphenoid sinus|Sphenoidal]] – may cause pain or pressure behind the eyes, though it is often felt at [[Vertex (anatomy)|top of the head]], over the [[Mastoid process|mastoid processes]], or the back of the head.<ref name="Terézhalmy-20093" />

=== Complications ===
{| class="wikitable" style="float: right; margin-left:15px; text-align:center"
|+Chandler classification
|-
!scope="col"| Stage
!scope="col"| Description
|-
!scope="row" style="text-align:left; font-weight:normal;"| I
| Preseptal cellulitis
|-
!scope="row" style="text-align:left; font-weight:normal;"| II
| Orbital cellulitis
|-
!scope="row" style="text-align:left; font-weight:normal;"| III
| Subperiosteal abscess
|-
!scope="row" style="text-align:left; font-weight:normal;"| IV
| Orbital abscess
|-
!scope="row" style="text-align:left; font-weight:normal;"| V
| Cavernous sinus septic thrombosis
|}
Complications are thought to be rare (1 case per 10,000).<ref name="pmid18206715"/> Infectious complications of acute bacterial sinusitis include [[Orbit (anatomy)|eye]], [[Cranial cavity|brain]] and [[Osseous|bone]] complications.<ref name=":0">{{Cite book |last1=Scholes |first1=Melissa A. |title=ENT secrets |last2=Ramakrishnan |first2=Vijay R. |date=May 9, 2022 |publisher=Elsevier Health Sciences |isbn=978-0-323-73358-8 |edition=5th |pages=155–160}}</ref>

==== Orbital complications ====
The Chandler classification is used to group orbital complications into five stages based on their severity.<ref>{{cite journal|vauthors=Chandler JR, Langenbrunner DJ, Stevens ER|date=September 1970|title=The pathogenesis of orbital complications in acute sinusitis|journal=The Laryngoscope|volume=80|issue=9|pages=1414–28|doi=10.1288/00005537-197009000-00007|pmid=5470225|s2cid=32773653}}</ref> Stage I, known as preseptal cellulitis, occurs when an infection develops in front of the [[orbital septum]].<ref name=":1">{{Citation|last1=Bae|first1=Crystal|title=Periorbital Cellulitis|date=2024|work=StatPearls|url=https://www.ncbi.nlm.nih.gov/books/NBK470408/|access-date=2024-11-13|place=Treasure Island (FL)|publisher=StatPearls Publishing|pmid=29261970|last2=Bourget|first2=Daniele}}</ref> It is thought to result from restricted [[Venous|venous drainage]] from the sinuses and affects the soft tissue of the eyelids and other superficial structures.<ref name=":1"/> Stage II, known as orbital cellulitis, occurs when infection develops behind the orbital septum and affects the [[Orbit (anatomy)|orbits]].<ref name=":1"/> This can result in [[Ophthalmoparesis|impaired eye movement]], [[Exophthalmos|protrusion of the eye]], and [[Chemosis|eye swelling]].<ref name=":1"/> Stage III, known as subperiosteal abscess, occurs when [[pus]] collects between walls of the orbit and the surrounding periosteal structures.<ref name=":1"/> This can result in impaired eye movement and acuity.<ref name=":1"/> Stage IV, known as orbital abscess, occurs when an abscess forms within the orbital tissue.<ref name=":1"/> This can result in severe vision impairment.<ref name=":1"/> Stage V, known as [[cavernous sinus thrombosis]], is considered an intracranial complication. It can occur as bacterial spread progresses, triggering blood clots that become trapped within the cavernous sinus.<ref>{{Citation|last1=Plewa|first1=Michael C.|title=Cavernous Sinus Thrombosis|date=2024 |work=StatPearls|place=Treasure Island (FL) |publisher=StatPearls Publishing|pmid=28846357|last2=Tadi|first2=Prasanna|last3=Gupta|first3=Mohit}}</ref> This can result in previously described symptoms within the opposite eye and, in severe cases, meningitis.<ref name=":1"/>

==== Intracranial complications ====
The proximity of the sinuses to the brain makes brain infections one of the most dangerous complications of acute bacterial sinusitis, especially when the frontal and sphenoid sinuses are involved. These infections can result from invasion of [[Anaerobic organisms|anaerobic bacteria]] through the bones or blood vessels. [[Abscesses]], [[meningitis]], and other life-threatening conditions may occur. In rare cases, mild personality changes, headache, altered consciousness, visual problems, seizures, [[coma]], and even death may occur.<ref name="Patient Education2">{{cite web |title=Sinusitus Complications |url=http://www.umm.edu/patiented/articles/what_symptoms_of_sinusitis_000062_4.htm |url-status=live |archive-url=https://web.archive.org/web/20100222004055/http://www.umm.edu/patiented/articles/what_symptoms_of_sinusitis_000062_4.htm |archive-date=2010-02-22 |work=Patient Education |publisher=University of Maryland}}</ref>

==== Osseous complications ====
A rare complication of acute sinusitis is a bone infection, known as [[osteomyelitis]], which affects the [[Frontal bone|frontal]] and other [[Facial skeleton|facial bones]].<ref name=":02">{{Cite journal |last1=Wadhwa |first1=Smriti |last2=Jain |first2=Shraddha |last3=Gupta |first3=Jaya |last4=Dobariya |first4=Harshil |last5=Pantbalekundri |first5=Nikhil |last6=Wadhwa |first6=Smriti |last7=Jain |first7=Shraddha |last8=Gupta |first8=Jaya |last9=Dobariya |first9=Harshil |last10=Pantbalekundri |first10=Nikhil |date=2024-02-13 |title=Osteomyelitis of Frontal Sinus: A Rare Sequelae of Acute Bacterial Sinusitis Associated With Anatomical Variations in the Frontal Sinus Drainage Pathway |journal=Cureus |language=en |volume=16 |issue=2 |article-number=e54158 |doi=10.7759/cureus.54158 |doi-access=free |issn=2168-8184 |pmc=10940872 |pmid=38496067}}</ref> Specifically, the combination of frontal sinusitis, osteomyelitis and subperiosteal abscess formation is referred to as [[Pott's puffy tumor]].<ref name="Patient Education3">{{cite web |title=Sinusitus Complications |url=http://www.umm.edu/patiented/articles/what_symptoms_of_sinusitis_000062_4.htm |url-status=live |archive-url=https://web.archive.org/web/20100222004055/http://www.umm.edu/patiented/articles/what_symptoms_of_sinusitis_000062_4.htm |archive-date=2010-02-22 |work=Patient Education |publisher=University of Maryland}}</ref><ref name=":02" />

'''Other complications'''

When an infection originating from a tooth or dental procedure affects the maxillary sinus it can lead to [[odontogenic sinusitis]] (ODS).<ref>{{cite journal |last1=Craig |first1=John R. |last2=Poetker |first2=David M. |last3=Aksoy |first3=Umut |last4=Allevi |first4=Fabiana |last5=Biglioli |first5=Federico |last6=Cha |first6=Bruce Y. |last7=Chiapasco |first7=Matteo |last8=Lechien |first8=Jerome R. |last9=Safadi |first9=Ahmad |last10=Simuntis |first10=Regimantas |last11=Tataryn |first11=Roderick |date=2021-02-14 |title=Diagnosing odontogenic sinusitis: An international multidisciplinary consensus statement |journal=International Forum of Allergy & Rhinology |language=en |volume=11 |issue=8 |pages=1235–1248 |doi=10.1002/alr.22777 |issn=2042-6976 |pmid=33583151 |doi-access=free |hdl-access=free |hdl=2027.42/168522}}</ref> Odontogenic sinusitis can often spread to nearby sinuses including the ethmoid, frontal, sphenoid sinuses, and the contralateral nasal cavity.<ref>{{cite journal |last1=Saibene |first1=Alberto Maria |last2=Pipolo |first2=Giorgia Carlotta |last3=Lozza |first3=Paolo |last4=Maccari |first4=Alberto |last5=Portaleone |first5=Sara Maria |last6=Scotti |first6=Alberto |last7=Borloni |first7=Roberto |last8=Messina |first8=Francesco |last9=Di Pasquale |first9=Daniele |last10=Felisati |first10=Giovanni |date=December 2014 |title=Redefining boundaries in odontogenic sinusitis: a retrospective evaluation of extramaxillary involvement in 315 patients: Odontogenic sinusitis extramaxillary involvement |url=http://doi.wiley.com/10.1002/alr.21400 |url-status=live |journal=International Forum of Allergy & Rhinology |language=en |volume=4 |issue=12 |pages=1020–1023 |doi=10.1002/alr.21400 |pmid=25196643 |s2cid=28835025 |archive-url=https://web.archive.org/web/20240225034048/https://onlinelibrary.wiley.com/doi/abs/10.1002/alr.21400 |archive-date=2024-02-25 |access-date=2021-03-27}}</ref> In rare instances, these infections may spread to the [[Orbit (anatomy)|orbit]], leading to orbital [[cellulitis]].

==Causes==

===Acute===
[[Acute (medical)|Acute]] sinusitis is usually precipitated by an earlier [[upper respiratory tract infection]], generally of [[virus|viral]] origin, mostly caused by [[rhinovirus]]es (with RVA and RVC giving more severe infection than RVB), [[coronavirus]]es, and [[Orthomyxoviridae|influenza viruses]], others caused by [[Adenoviridae|adenoviruses]], [[human parainfluenza viruses]], [[human respiratory syncytial virus]], [[enterovirus]]es other than rhinoviruses, and [[metapneumovirus]]. If the infection is of bacterial origin, the most common three causative agents are ''[[Streptococcus pneumoniae]] (38%)'', ''[[Haemophilus influenzae]] (36%)'', and ''[[Moraxella catarrhalis]] (16%)''.<ref name="pmid31613481">{{cite journal |vauthors=DeBoer DL, Kwon E |date=2020 |title=Acute Sinusitis |journal=Statpearls |pmid=31613481}}[[File:CC-BY_icon.svg|50x50px]] Text was copied from this source, which is available under a [[ccorg:licenses/by/4.0/|Creative Commons Attribution 4.0 International License]] {{Cite web |url=https://creativecommons.org/licenses/by/4.0/ |title=Deed - Attribution 4.0 International - Creative Commons |access-date=2020-11-27 |archive-date=2017-10-16 |archive-url=https://web.archive.org/web/20171016050101/https://creativecommons.org/licenses/by/4.0/ |url-status=bot: unknown }}.</ref><ref name="pmid31430424">{{cite journal |vauthors=Basharat U, Aiche MM, Kim MM, Sohal M, Chang EH |title=Are rhinoviruses implicated in the pathogenesis of sinusitis and chronic rhinosinusitis exacerbations? A comprehensive review |journal=Int Forum Allergy Rhinol |volume=9 |issue=10 |pages=1159–1188 |date=October 2019 |pmid=31430424 |doi=10.1002/alr.22403 |s2cid=201117207 }}</ref> Until recently, ''H. influenzae'' was the most common bacterial agent to cause sinus infections. However, introduction of the ''H. influenzae'' type B (Hib) vaccine has dramatically decreased these infections, and now non-typable ''H. influenzae'' (NTHI) is predominantly seen in clinics. Other sinusitis-causing [[bacterial]] [[pathogen]]s include ''[[Staphylococcus aureus|S. aureus]]'' and other [[streptococci]] [[species]], [[Anaerobic organism|anaerobic bacteria]] and, less commonly, [[Gram-negative]] bacteria. Viral sinusitis typically lasts for 7 to 10 days.<ref name="pmid18206715" />

[[Acute (medical)|Acute]] episodes of sinusitis can also result from [[fungus|fungal]] invasion. These infections are typically seen in people with [[diabetes]] or other [[immunodeficiency|immune deficiencies]] (such as [[AIDS]] or [[Organ transplant|transplant]] on immunosuppressive antirejection medications) and can be life-threatening. In type I diabetics, ketoacidosis can be associated with sinusitis due to [[mucormycosis]].<ref>{{EMedicine|article|222551|Mucormycosis}}</ref>

===Chronic===
====Definition and nomenclature====
By definition, chronic sinusitis lasts longer than 12 weeks and can be caused by many different diseases that share chronic inflammation of the sinuses as a common symptom. It is subdivided into cases with and without [[nasal polyp|polyps]]. When polyps are present, the condition is called chronic [[hyperplastic]] sinusitis; however, the causes are poorly understood.<ref name="pmid18206715">{{cite journal | vauthors = Leung RS, Katial R | title = The diagnosis and management of acute and chronic sinusitis | journal = Primary Care | volume = 35 | issue = 1 | pages = 11–24, v-vi | date = March 2008 | pmid = 18206715 | doi = 10.1016/j.pop.2007.09.002 }}</ref> It may develop with anatomic derangements, including deviation of the nasal septum and the presence of concha bullosa (pneumatization of the middle concha) that inhibit the outflow of mucus, or with allergic rhinitis, asthma, cystic fibrosis, and dental infections.<ref>{{cite book|isbn=978-0-323-54384-2|title=Oral radiology: principles and interpretation|publisher=Elsevier|vauthors=White SC, Pharoah MJ|date=12 September 2018 |location=St. Louis, Missouri}}</ref>

Chronic rhinosinusitis represents a multifactorial inflammatory disorder, rather than simply a persistent bacterial infection.<ref name="pmid18206715" /> The medical management of chronic rhinosinusitis is now focused upon controlling the inflammation that predisposes people to obstruction, reducing the incidence of infections.<ref name="pmid21735433">{{cite journal | vauthors = Ahmed J, Pal S, Hopkins C, Jayaraj S | title = Functional endoscopic balloon dilation of sinus ostia for chronic rhinosinusitis | journal = The Cochrane Database of Systematic Reviews | issue = 7 | date = July 2011 | pmid = 21735433 | doi = 10.1002/14651858.CD008515.pub2 }}</ref> Surgery may be needed if medications are not working.<ref name="pmid21735433" />

During nasal endoscopy, an accessory maxillary ostium can sometimes be observed in the middle meatus. While not all are functionally active, in certain cases, mucus exiting the natural maxillary ostium may re-enter the sinus through the accessory ostium. This mucus recirculation may be associated with chronic maxillary sinusitis.<ref>{{cite journal | author = Bani-Ata M, Aleshawi A, Khatatbeh A, Al-Domaidat D, Alnussair B, Al-Shawaqfeh R, Allouh M | date = May 2020 | title = Accessory Maxillary Ostia: Prevalence of an Anatomical Variant and Association with Chronic Sinusitis | journal = Int J Gen Med | volume = 13 | issue = | pages = 163–168 | doi = 10.2147/IJGM.S253569 | doi-access = free | pmid = 32440195 | pmc = 7217303 }}</ref>

Attempts have been made to provide a more consistent nomenclature for subtypes of chronic sinusitis. The presence of [[Eosinophil granulocyte|eosinophils]] in the mucous lining of the nose and paranasal sinuses has been demonstrated in many people, and this has been termed eosinophilic mucin rhinosinusitis (EMRS). Cases of EMRS may be related to an allergic response, but allergy is not often documented, resulting in further subcategorization into allergic and nonallergic EMRS.<ref>{{cite journal | vauthors = Chakrabarti A, Denning DW, Ferguson BJ, Ponikau J, Buzina W, Kita H, Marple B, Panda N, Vlaminck S, Kauffmann-Lacroix C, Das A, Singh P, Taj-Aldeen SJ, Kantarcioglu AS, Handa KK, Gupta A, Thungabathra M, Shivaprakash MR, Bal A, Fothergill A, Radotra BD | title = Fungal rhinosinusitis: a categorization and definitional schema addressing current controversies | journal = The Laryngoscope | volume = 119 | issue = 9 | pages = 1809–18 | date = September 2009 | pmid = 19544383 | pmc = 2741302 | doi = 10.1002/lary.20520 }}</ref>

====Fungi====
A more recent, and still debated, development in chronic sinusitis is the role that [[fungi]] play in this disease.<ref>{{cite news | first = Sandrad G. | last = Boodman | url = https://www.washingtonpost.com/archive/lifestyle/wellness/1999/11/23/mayo-report-on-sinusitis-draws-skeptics/5bf22891-243b-4f8b-bbcb-8aedb0867062/ | title = Mayo Report on Sinusitis Draws Skeptics | date = 1999-11-23 | newspaper = The Washington Post | access-date = 2018-06-01 | archive-date = 2019-03-06 | archive-url = https://web.archive.org/web/20190306050544/https://www.washingtonpost.com/archive/lifestyle/wellness/1999/11/23/mayo-report-on-sinusitis-draws-skeptics/5bf22891-243b-4f8b-bbcb-8aedb0867062/ | url-status = live }}</ref> Whether fungi are a definite factor in the development of chronic sinusitis remains unclear, and if they are, what is the difference between those who develop the disease and those who remain free of symptoms. Trials of antifungal treatments have had mixed results.<ref>{{cite journal | vauthors = Rank MA, Adolphson CR, Kita H | title = Antifungal therapy for chronic rhinosinusitis: the controversy persists | journal = Current Opinion in Allergy and Clinical Immunology | volume = 9 | issue = 1 | pages = 67–72 | date = February 2009 | pmid = 19532095 | pmc = 3914414 | doi = 10.1097/ACI.0b013e328320d279 }}</ref>

====One airway theory====
Recent theories of sinusitis indicate that it often occurs as part of a spectrum of diseases that affect the [[respiratory tract]] (''i.e.'', the "one airway" theory) and is often linked to [[asthma]].<ref>{{cite journal | vauthors = Grossman J | title = One airway, one disease | journal = Chest | volume = 111 | issue = 2 Suppl | pages = 11S–16S | date = February 1997 | pmid = 9042022 | doi = 10.1378/chest.111.2_Supplement.11S }}</ref><ref>{{cite journal | vauthors = Cruz AA | title = The 'united airways' require an holistic approach to management | journal = Allergy | volume = 60 | issue = 7 | pages = 871–4 | date = July 2005 | pmid = 15932375 | doi = 10.1111/j.1398-9995.2005.00858.x | s2cid = 7490538 | doi-access = free }}</ref>

====Smoking====
Both smoking and [[secondhand smoke]] are associated with chronic rhinosinusitis.<ref name="pmid21890184">{{cite journal |vauthors=Hamilos DL |date=October 2011 |title=Chronic rhinosinusitis: epidemiology and medical management |journal=The Journal of Allergy and Clinical Immunology |volume=128 |issue=4 |pages=693–707; quiz 708–9 |doi=10.1016/j.jaci.2011.08.004 |pmid=21890184}}</ref>

====Air pollution====
Exposure to fine particulate matter (PM2.5), which consists of particles with a diameter of less than 2.5 micrometers, has been associated with an increased risk of developing rhinosinusitis.<ref name="Kim2015">{{cite journal |last=Kim |first=Hojoong |title=Effects of Particulate Matter (PM<sub>2.5</sub>) on Nasal Mucociliary Transport and Mucus Secretion in Human Nasal Epithelial Cells |journal=American Journal of Rhinology & Allergy |volume=29 |issue=6 |pages=383–386 |year=2015 |doi=10.2500/ajra.2015.29.4236 |pmid=26634607}}</ref><ref name="Hwang2020">{{cite journal |last=Hwang |first=Shinyeon |title=Long-term exposure to ambient air pollutants and chronic rhinosinusitis in adulthood |journal=International Forum of Allergy & Rhinology |volume=10 |issue=6 |pages=748–756 |year=2020 |doi=10.1002/alr.22520 |pmid=32129401}}</ref> PM2.5 particles can penetrate deep into the respiratory tract, reaching the nasal and sinus mucosa, leading to inflammation and impaired mucociliary clearance.<ref name="Reh2012">{{cite journal |last=Reh |first=Douglas D. |title=Environmental exposures and chronic rhinosinusitis: a systematic review |journal=Otolaryngology–Head and Neck Surgery |volume=146 |issue=5 |pages=733–741 |year=2012 |doi=10.1016/j.jhsa.2012.01.003 |pmid=22386545}}</ref> Individuals living in areas with higher concentrations of PM2.5 experience increased symptoms and exacerbations of chronic rhinosinusitis.<ref name="Zhang2014">{{cite journal |last=Zhang |first=Zhenyu |title=Association between indoor air pollution and chronic rhinosinusitis: a systematic review |journal=International Forum of Allergy & Rhinology |volume=4 |issue=1 |pages=4–15 |year=2014 |doi=10.1002/alr.21254 |pmid=24122709}}</ref> The fine particles cause oxidative stress and inflammation, contributing to the pathogenesis of rhinosinusitis.<ref name="Harvey2015">{{cite journal |last=Harvey |first=Richard J. |title=Mucosal inflammation in chronic rhinosinusitis: response to medical treatment |journal=Current Opinion in Otolaryngology & Head and Neck Surgery |volume=23 |issue=1 |pages=1–6 |year=2015 |doi=10.1097/MOO.0000000000000122 |pmid=25490611 |url=https://escholarship.org/uc/item/4s33t2jp |access-date=2024-11-23 |archive-date=2024-04-28 |archive-url=https://web.archive.org/web/20240428153407/https://escholarship.org/uc/item/4s33t2jp |url-status=live }}</ref>

While both PM10 (particles less than 10 micrometers) and PM2.5 can affect the respiratory system, PM2.5 particles are more closely associated with rhinosinusitis due to their ability to reach deeper into the sinus cavities.<ref name="Maniscalco2015">{{cite journal |last=Maniscalco |first=Michele |title=High atmospheric particulate matter (PM<sub>2.5</sub>) exposure is associated with increased nasal inflammation in allergic rhinitis |journal=Rhinology |volume=53 |issue=3 |pages=193–199 |year=2015 |doi=10.3950/jibiinkoka.118.213 |pmid=26349337|doi-access=free }}</ref> These smaller particles bypass the nasal hair filtering mechanism and deposit in the mucous membranes of the sinuses, leading to greater inflammatory responses.<ref name="D'Amato2018">{{cite journal |last=D'Amato |first=Gennaro |title=Climate change, air pollution, and allergic respiratory diseases: a call to action for health professionals |journal=Multidisciplinary Respiratory Medicine |volume=13 |year=2018 |issue=9 Suppl |pages=S8–S41 |doi=10.1186/s40248-018-0122-7 |doi-broken-date=12 July 2025 |doi-access=free |pmid=29410723|pmc=5788261 }}</ref>

The World Health Organization (WHO) recommends that annual mean concentrations of PM2.5 should not exceed '''5&nbsp;μg/m<sup>3</sup>''', and 24-hour mean exposures should not exceed '''15&nbsp;μg/m<sup>3</sup>''' to minimize health risks.<ref name="WHO2021">{{cite book |title=WHO global air quality guidelines: Particulate matter (PM<sub>2.5</sub> and PM<sub>10</sub>), ozone, nitrogen dioxide, sulfur dioxide and carbon monoxide |url=https://www.who.int/publications/i/item/9789240034228 |date=22 September 2021|publisher=World Health Organization |isbn=978-92-4-003422-8 |access-date=23 November 2024}}</ref> Exposure to concentrations above these thresholds has been linked to an increased incidence and severity of rhinosinusitis and other respiratory diseases.<ref name="Peden2020">{{cite journal |last=Peden |first=David B. |title=Mechanisms of pollution-induced airway disease: in vivo studies |journal=Allergy, Asthma & Clinical Immunology |volume=16 |issue=1 |year=2020 |pages=680–681 |doi=10.1186/s13223-020-00431-3 |doi-access=free |pmid=32393680|pmc=7387257 }}</ref>

====Other diseases====
Other diseases such as [[cystic fibrosis]] and [[granulomatosis with polyangiitis]] can also cause chronic sinusitis.<ref>{{cite journal | vauthors = Marks SC, Kissner DG | s2cid = 5606258 | title = Management of sinusitis in adult cystic fibrosis | journal = American Journal of Rhinology | volume = 11 | issue = 1 | pages = 11–4 | year = 1997 | pmid = 9065342 | doi = 10.2500/105065897781446810 }}</ref>

===Maxillary sinus===
[[Maxillary sinus|Maxillary]] sinusitis may also develop from dental problems. These cases were calculated to be about 40% in one study and 50% in another.<ref name="American Association of Endodontists-2018"/> The cause of this situation is usually a [[periapical]] or [[periodontal]] infection of a maxillary [[posterior (anatomy)|posterior]] tooth, where the inflammatory [[exudate]] has eroded through the bone superiorly to drain into the maxillary sinus.<ref name="American Association of Endodontists-2018"/>

An estimated 0.5 to 2.0% of viral rhinosinusitis (VRS) cases in adults and 5 to 10% in children develop superimposed bacterial infections.<ref name="pmid31613481"/>

==Pathophysiology==
Chronic rhinosinusitis is a multifactorial process hypothesized to be caused by inflammatory processes driven by dysfunction between local host and environmental interactions.<ref name=":12">{{Cite journal |last1=Fokkens |first1=W.J. |last2=Lund |first2=V.J. |last3=Hopkins |first3=C. |last4=Hellings |first4=P.W. |last5=Kern |first5=R. |last6=Reitsma |first6=S. |last7=Toppila-Salmi |first7=S. |last8=Bernal-Sprekelsen |first8=M. |last9=Mullol |first9=J. |last10=Alobid |first10=I. |last11=Terezinha Anselmo-Lima |first11=W. |last12=Bachert |first12=C. |last13=Baroody |first13=F. |last14=von Buchwald |first14=C. |last15=Cervin |first15=A. |date=2020-02-01 |title=European Position Paper on Rhinosinusitis and Nasal Polyps 2020 |url=https://www.rhinologyjournal.com/Documents/Supplements/supplement_29.pdf |journal=Rhinology  |volume=58 |issue=Suppl S29 |pages=1–464 |doi=10.4193/Rhin20.600|pmid=32077450 }}</ref>  It is divided into two [[phenotype]]s that depend on the presence or absence of [[nasal polyp]]s.<ref name=":22">{{Cite journal |last1=Kato |first1=Atsushi |last2=Schleimer |first2=Robert P. |last3=Bleier |first3=Benjamin S. |date=May 2022 |title=Mechanisms and pathogenesis of chronic rhinosinusitis |journal=Journal of Allergy and Clinical Immunology |volume=149 |issue=5 |pages=1491–1503 |doi=10.1016/j.jaci.2022.02.016 |issn=0091-6749 |pmc=9081253 |pmid=35245537}}</ref> Chronic rhinosinusitis with nasal polyps and chronic rhinosinusitis without nasal polyps are thought to have two different inflammatory pathways, with the latter form driven by a [[Th1 response]] and the former driven by a [[T helper cell|Th2 response]].<ref>{{Cite book |last1=Scholes |first1=Melissa A. |title=ENT secrets |last2=Ramakrishnan |first2=Vijay R. |date=May 9, 2022 |publisher=Elsevier Health Sciences |isbn=978-0-323-73358-8 |edition=5th |pages=155–160}}</ref>  Both pathways result in an increase in inflammatory molecules ([[Cytokine|cytokines]]). The Th1 response is characterized by secretion of [[interferon gamma]].<ref name=":22" /> The Th2 response is characterized by secretion of [[interleukin-4 receptor]], [[interleukin 5]], and [[interleukin 13]].<ref name=":22" /> Both forms of chronic rhinosinusitis are considered to be highly heterogeneous, each with the ability to demonstrate three inflammatory [[endotype]]s, the third being a [[T helper cell|Th17 response]].<ref name=":22" />

==Diagnosis==
===Classification===
[[File:Otorhinolaryngology - Sinusitis -- Smart-Servier.png|thumb|upright=0.9|Illustration depicting sinusitis, note the fluid in the sini]]

Sinusitis (or rhinosinusitis) is defined as an inflammation of the [[nasal mucosa|mucous membrane]] that lines the [[paranasal sinuses]] and is classified chronologically into several categories:<ref name="Radojicic">{{cite web |url=http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/allergy/rhino-sinusitis/ |publisher=[[Cleveland Clinic]] | first = Christine | last = Radojicic |title=Sinusitis |work=Disease Management Project |access-date=November 26, 2012 |url-status=live |archive-url=https://web.archive.org/web/20121114060719/http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/allergy/rhino-sinusitis/ |archive-date=November 14, 2012 }}</ref>
* [[Acute (medicine)|Acute]] sinusitis – A new infection that may last up to four weeks and can be subdivided symptomatically into severe and nonsevere. Some use definitions up to 12 weeks.<ref name="pmid25833927">{{cite journal |vauthors=Rosenfeld RM, Piccirillo JF, Chandrasekhar SS, Brook I, Kumar KA, Kramper M, Orlandi RR, Palmer JN, Patel ZM, Peters A, Walsh SA, Corrigan MD |date=April 2015 |title=Clinical practice guideline (update): Adult Sinusitis Executive Summary |journal=Otolaryngology–Head and Neck Surgery |volume=152 |issue=4 |pages=598–609 |doi=10.1177/0194599815574247 |pmid=25833927 |s2cid=206469424 |doi-access=free}}</ref>
* Recurrent acute sinusitis – Four or more full episodes of acute sinusitis that occur within one year
* [[Subacute]] sinusitis – An infection that lasts between four and 12 weeks, and represents a transition between acute and chronic infection.
* [[Chronic (medicine)|Chronic]] sinusitis – When the signs and symptoms last for more than 12 weeks.<ref name="pmid25833927"/>
* Acute exacerbation of chronic sinusitis – When the signs and symptoms of chronic sinusitis exacerbate, but return to baseline after treatment.

Roughly 90% of adults have had sinusitis at some point in their lives.<ref>{{cite journal | vauthors = Pearlman AN, Conley DB | title = Review of current guidelines related to the diagnosis and treatment of rhinosinusitis | journal = Current Opinion in Otolaryngology & Head and Neck Surgery | volume = 16 | issue = 3 | pages = 226–30 | date = June 2008 | pmid = 18475076 | doi = 10.1097/MOO.0b013e3282fdcc9a | s2cid = 23638755 }}</ref>

===Acute===
Health care providers distinguish bacterial and viral sinusitis by [[watchful waiting]].<ref name="pmid25833927"/> If a person has had sinusitis for fewer than 10 days without the symptoms becoming worse, then the infection is presumed to be viral.<ref name="pmid25833927"/> When symptoms last more than 10 days or get worse during that time, then the infection is considered bacterial sinusitis.<ref name="pmid17761281"/> Pain in the teeth and bad breath are also more indicative of bacterial disease.<ref>{{cite journal | vauthors = Ebell MH, McKay B, Dale A, Guilbault R, Ermias Y | title = Accuracy of Signs and Symptoms for the Diagnosis of Acute Rhinosinusitis and Acute Bacterial Rhinosinusitis | journal = Annals of Family Medicine | volume = 17 | issue = 2 | pages = 164–172 | date = March 2019 | pmid = 30858261 | pmc = 6411403 | doi = 10.1370/afm.2354 }}</ref>

Imaging by either X-ray, CT, or MRI is generally not recommended unless complications develop.<ref name="pmid17761281">{{cite journal | vauthors = Rosenfeld RM, Andes D, Bhattacharyya N, Cheung D, Eisenberg S, Ganiats TG, Gelzer A, Hamilos D, Haydon RC, Hudgins PA, Jones S, Krouse HJ, Lee LH, Mahoney MC, Marple BF, Mitchell CJ, Nathan R, Shiffman RN, Smith TL, Witsell DL | title = Clinical practice guideline: adult sinusitis | journal = Otolaryngology–Head and Neck Surgery | volume = 137 | issue = 3 Suppl | pages = S1-31 | date = September 2007 | pmid = 17761281 | doi = 10.1016/j.otohns.2007.06.726 | s2cid = 16593182 | doi-access = free }}</ref> Pain caused by sinusitis is sometimes confused for pain caused by [[pulpitis]] (toothache) of the maxillary teeth, and vice versa. Classically, the increased pain when tilting the head forwards separates sinusitis from [[pulpitis]].<ref>{{Cite web |title=Sinus infection and toothache: Any connection? |url=https://www.mayoclinic.org/diseases-conditions/acute-sinusitis/expert-answers/toothache/faq-20058299 |access-date=2025-03-18 |website=Mayo Clinic |language=en}}</ref>

For cases of maxillary sinusitis, limited field [[Cone beam computed tomography|CBCT]] imaging, as compared to [[periapical]] [[radiograph]]s, improves the ability to detect the teeth as the sources for sinusitis. A coronal CT picture may also be useful.<ref name="American Association of Endodontists-2018"/>

===Chronic===
For sinusitis lasting more than 12 weeks, a [[CT scan]] is recommended.<ref name="pmid17761281" /> On a CT scan, acute sinus secretions have a [[radiodensity]] of 10 to 25 [[Hounsfield unit]]s (HU). In a more chronic state, they become more [[Viscosity|viscous]], with a radiodensity of 30 to 60 HU.<ref>[https://books.google.com/books?id=FxUgUBVBmUUC&pg=PA674 Page 674] {{webarchive|url=https://web.archive.org/web/20170216044325/https://books.google.com/books?id=FxUgUBVBmUUC&pg=PA674 |date=2017-02-16 }} in: {{cite book|title=Cummings Otolaryngology – Head and Neck Surgery, 3-Volume Set| vauthors = Flint PW, Haughey BH, Niparko JK, Richardson MA, Lund VJ, Robbins KT, Lesperance MM, Thomas JR | author-link3 = John Niparko |publisher=Elsevier Health Sciences|year=2010|isbn=978-0-323-08087-3}}</ref>

Nasal [[endoscopy]] and clinical symptoms are also used to make a positive diagnosis.<ref name="pmid18206715"/> A tissue sample for [[histology]] and [[cultures]] can also be collected and tested.<ref>Harrison's Manual of Medicine 16/e</ref> Nasal endoscopy involves inserting a flexible [[fiber-optic]] tube with a light and camera at its tip into the nose to examine the nasal passages and sinuses.

Sinus infections, if they result in tooth pain, usually present with pain involving more than one of the upper teeth, whereas a toothache usually involves a single tooth. Dental examination and appropriate radiography help rule out pain arising from a tooth.<ref name="Burket-2014">{{cite book|title=Burket's oral medicine|publisher=Burket's oral medicine|last=Glick|first=Michael|date=30 June 2014 |isbn=978-1-60795-280-0|edition=12th|location=Shelton, Connecticut|page=341|oclc=903962852}}</ref>

<gallery mode="packed" widths="360px" heights="220">
Image:Sinuses and Sinusitis (5937085231).jpg|CT of chronic sinusitis
File:CT of chronic sinuitis.jpg|[[CT scan]] of chronic sinusitis, showing a filled right maxillary sinus with sclerotic thickened bone
File:Brain MRI 112010 rgbca.png|MRI image showing sinusitis. Edema and mucosal thickening appear in both maxillary sinuses.
File:RtmaxobitinfectteethCT.png|Maxillary sinusitis caused by a dental infection associated with [[periorbital cellulitis]]
File:FrontalSinusitisMark.png|Frontal sinusitis
File:Maxilar sinusites.jpg|[[Projectional radiography|X-ray]] of left-sided maxillary sinusitis marked by an arrow. There is a lack of air transparency, indicating fluid in contrast to the other side.
</gallery>

==Treatment==
{| style="float:right; width:40em; border:solid 1px #999999; margin:0 0 1em 1em;"
|+ style="background-color: #CCEEEE;" | Treatments for sinusitis<ref name="American Academy of Family Physicians-2012">{{cite web |author1 = Consumer Reports |author2 = American Academy of Family Physicians |author1-link = Consumer Reports |author2-link = American Academy of Family Physicians |date = April 2012 |title = Treating sinusitis: Don't rush to antibiotics |publisher = [[Consumer Reports]] |work = Choosing wisely: an initiative of the [[ABIM Foundation]] |url = http://consumerhealthchoices.org/wp-content/uploads/2012/04/ChoosingWiselySinusitisAAFP.pdf |access-date = August 17, 2012 |url-status = live |archive-url = https://web.archive.org/web/20120611205432/http://consumerhealthchoices.org/wp-content/uploads/2012/04/ChoosingWiselySinusitisAAFP.pdf |archive-date = June 11, 2012 }}</ref><ref>{{cite web |author = ((American Academy of Allergy, Asthma, and Immunology)) |author-link = American Academy of Allergy, Asthma, and Immunology |title = Five things physicians and patients should question |publisher = [[American Academy of Allergy, Asthma, and Immunology]] |work = Choosing Wisely: an initiative of the [[ABIM Foundation]] |url = http://choosingwisely.org/wp-content/uploads/2012/04/5things_12_factsheet_AAAAI.pdf |access-date = August 14, 2012 |url-status = live |archive-url = https://web.archive.org/web/20121103151124/http://choosingwisely.org/wp-content/uploads/2012/04/5things_12_factsheet_AAAAI.pdf |archive-date = November 3, 2012 }}</ref>
|-
!scope="col"| Treatment
!scope="col"| Indication
!scope="col"| Rationale
|-
|-
!scope="row" style="text-align:left; font-weight:normal;"| Time
| Viral and some bacterial sinusitis
| Sinusitis is usually caused by a virus, which is not affected by antibiotics.<ref name="American Academy of Family Physicians-2012"/>
|-
!scope="row" style="text-align:left; font-weight:normal;"| Antibiotics
| Bacterial sinusitis
| Cases accompanied by extreme pain, skin infection, or that last a long time may be caused by bacteria.<ref name="American Academy of Family Physicians-2012"/>
|-
!scope="row" style="text-align:left; font-weight:normal;"| [[Nasal irrigation]]
| [[Nasal congestion]]
| Can provide relief by helping decongest.<ref name="American Academy of Family Physicians-2012"/>
|-
!scope="row" style="text-align:left; font-weight:normal;"| Drink liquids
| Thick [[phlegm]]
| Remaining hydrated loosens mucus.<ref name="American Academy of Family Physicians-2012"/>
|-
!scope="row" style="text-align:left; font-weight:normal;"| [[Antihistamines]]
| Concern with [[allergies]]
| Antihistamines do not relieve typical sinusitis or cold symptoms much; this treatment is not needed in most cases.<ref name="American Academy of Family Physicians-2012"/>
|-
!scope="row" style="text-align:left; font-weight:normal;"| [[Nasal spray]]
| Desire for temporary relief
| Tentative evidence that it helps symptoms.<ref name="pmid25892369">{{cite journal |vauthors=King D, Mitchell B, Williams CP, Spurling GK |date=April 2015 |title=Saline nasal irrigation for acute upper respiratory tract infections |url=http://espace.library.uq.edu.au/view/UQ:201653/UQ201653_OA.pdf |url-status=live |journal=The Cochrane Database of Systematic Reviews |volume=2015 |issue=4 |doi=10.1002/14651858.CD006821.pub3 |pmc=9475221 |pmid=25892369 |archive-url=https://web.archive.org/web/20210829061619/https://espace.library.uq.edu.au/data/UQ_201653/UQ201653_OA.pdf?Expires=1630217866&Key-Pair-Id=APKAJKNBJ4MJBJNC6NLQ&Signature=fvzZFSRIkQZTLEhLp~QFYol~hVWVs5Yo2o0Vw3BhGOL7U3pmZx7K1xwMdix20C-ZBOBTDrFZyWfczpiMKk7xmMWYUsYU8tEF9SRghcv~x04vWlZkkUuL3E7OHRYrkCFawyesJkkEEQO5sQxtD0LLWuoQWlT7yRRWk4ZqrLeW7OCsFY5NhBYavteJhqCqtWifH5hIamsdfCYNZnVKx4mp66bQ5L5iozTDtmriPethrPxdoRvyPvYoPscI~ayOcvCjCjdYxsooSxLtw1KPpsbBbtEACOPp35YxrEPcON9XJO04wJeqpcy9FsRhJHM1Gg1-b8p5xUSx3LRrF42Dirskaw__ |archive-date=2021-08-29 |access-date=2018-04-20}}</ref> Does not treat cause. Not recommended for more than three days' use.<ref name="American Academy of Family Physicians-2012"/>
|-
|}

Recommended treatments for most cases of sinusitis include rest and drinking enough water to thin the mucus.<ref name="American Academy of Allergy, Asthma, and Immunology-2012">{{Citation |author1 = Consumer Reports |author2-link = American Academy of Allergy, Asthma, and Immunology |author2 = ((American Academy of Allergy, Asthma, and Immunology)) |date = July 2012 |title = Treating sinusitis: Don't rush to antibiotics |publisher = [[Consumer Reports]] |work = Choosing Wisely: an initiative of the [[ABIM Foundation]] |url = http://consumerhealthchoices.org/wp-content/uploads/2012/04/ChoosingWiselySinusitusAAAAI.pdf |access-date = August 14, 2012 |url-status = live |archive-url = https://web.archive.org/web/20130124031216/http://consumerhealthchoices.org/wp-content/uploads/2012/04/ChoosingWiselySinusitusAAAAI.pdf |archive-date = January 24, 2013 |author1-link = Consumer Reports }}</ref> Antibiotics are not recommended for most cases.<ref name="American Academy of Allergy, Asthma, and Immunology-2012"/><ref>{{cite journal | vauthors = Lemiengre MB, van Driel ML, Merenstein D, Liira H, Mäkelä M, De Sutter AI | title = Antibiotics for acute rhinosinusitis in adults | journal = The Cochrane Database of Systematic Reviews | volume = 2018 | date = September 2018 | issue = 9 | pmid = 30198548 | pmc = 6513448 | doi = 10.1002/14651858.CD006089.pub5 }}</ref>

Breathing high-temperature steam, such as from a hot shower or [[gargling]], can relieve symptoms.<ref name="American Academy of Allergy, Asthma, and Immunology-2012"/><ref>{{cite journal | vauthors = Harvey R, Hannan SA, Badia L, Scadding G | title = Nasal saline irrigations for the symptoms of chronic rhinosinusitis | journal = The Cochrane Database of Systematic Reviews | issue = 3 | date = July 2007 | pmid = 17636843 | doi = 10.1002/14651858.CD006394.pub2 | veditors = Harvey R }}</ref> There is tentative evidence for [[nasal irrigation]] in acute sinusitis, for example during [[upper respiratory infection]]s.<ref name="pmid25892369"/> [[Decongestant]] [[nasal spray]]s containing [[oxymetazoline]] may provide relief, but these medications should not be used for more than the recommended period. Longer use may cause [[rhinitis medicamentosa|rebound sinusitis]].<ref>{{EMedicine|article|995056|Rhinitis medicamentosa}}</ref> It is unclear if nasal irrigation, [[antihistamine]]s, or decongestants work in children with acute sinusitis.<ref>{{cite journal | vauthors = Shaikh N, Wald ER | title = Decongestants, antihistamines and nasal irrigation for acute sinusitis in children | journal = The Cochrane Database of Systematic Reviews | volume = 2014 | issue = 10 | date = October 2014 | pmid = 25347280 | doi = 10.1002/14651858.CD007909.pub4 | pmc = 7182143 }}</ref> There is no clear evidence that plant extracts such as ''[[Cyclamen purpurascens|Cyclamen europaeum]]'' are effective as an intranasal wash to treat acute sinusitis.<ref>{{cite journal | vauthors = Zalmanovici Trestioreanu A, Barua A, Pertzov B | title = Cyclamen europaeum extract for acute sinusitis | journal = The Cochrane Database of Systematic Reviews | volume = 5 | date = May 2018 | issue = 8 | pmid = 29750825 | pmc = 6494494 | doi = 10.1002/14651858.CD011341.pub2 }}</ref> Evidence is inconclusive on whether anti-fungal treatments improve symptoms or quality of life.<ref>{{cite journal | vauthors = Head K, Sharp S, Chong LY, Hopkins C, Philpott C | title = Topical and systemic antifungal therapy for chronic rhinosinusitis | journal = The Cochrane Database of Systematic Reviews | volume = 2018 | date = September 2018 | issue = 9 | pmid = 30199594 | pmc = 6513454 | doi = 10.1002/14651858.cd012453.pub2 }}</ref>

===Antibiotics===
Most cases of sinusitis are caused by viruses and resolve without antibiotics.<ref name="pmid18206715"/> However, if symptoms do not resolve within 10 days, either [[amoxicillin]] or [[amoxicillin/clavulanate]] are reasonable antibiotics for [[Therapy#Lines of therapy|first treatment]] with [[amoxicillin/clavulanate]] being slightly superior to [[amoxicillin]] alone but with more side effects.<ref name="pmid33236525">{{cite journal |last1=Orlandi |first1=Richard R. |last2=Kingdom |first2=Todd T. |last3=Smith |first3=Timothy L. |last4=Bleier |first4=Benjamin |last5=DeConde |first5=Adam |last6=Luong |first6=Amber U. |last7=Poetker |first7=David M. |last8=Soler |first8=Zachary |last9=Welch |first9=Kevin C. |last10=Wise |first10=Sarah K. |last11=Adappa |first11=Nithin |last12=Alt |first12=Jeremiah A. |last13=Anselmo-Lima |first13=Wilma Terezinha |last14=Bachert |first14=Claus |last15=Baroody |first15=Fuad M. |year=2021 |title=International consensus statement on allergy and rhinology: rhinosinusitis 2021 |url=https://ueaeprints.uea.ac.uk/id/eprint/77501/1/Accepted_Manuscript.pdf |url-status=live |journal=International Forum of Allergy & Rhinology |publisher=Wiley |volume=11 |issue=3 |pages=213–739 |doi=10.1002/alr.22741 |issn=2042-6976 |pmid=33236525 |s2cid=227165628 |archive-url=https://web.archive.org/web/20230307191717/https://ueaeprints.uea.ac.uk/id/eprint/77501/1/Accepted_Manuscript.pdf |archive-date=2023-03-07 |access-date=2023-01-21 |last16=Batra |first16=Pete S. |last17=Bernal-Sprekelsen |first17=Manuel |last18=Beswick |first18=Daniel |last19=Bhattacharyya |first19=Neil |last20=Chandra |first20=Rakesh K. |last21=Chang |first21=Eugene H. |last22=Chiu |first22=Alexander |last23=Chowdhury |first23=Naweed |last24=Citardi |first24=Martin J. |last25=Cohen |first25=Noam A. |last26=Conley |first26=David B. |last27=DelGaudio |first27=John |last28=Desrosiers |first28=Martin |last29=Douglas |first29=Richard |last30=Eloy |first30=Jean Anderson |last31=Fokkens |first31=Wytske J. |last32=Gray |first32=Stacey T. |last33=Gudis |first33=David A. |last34=Hamilos |first34=Daniel L. |last35=Han |first35=Joseph K. |last36=Harvey |first36=Richard |last37=Hellings |first37=Peter |last38=Holbrook |first38=Eric H. |last39=Hopkins |first39=Claire |last40=Hwang |first40=Peter |last41=Javer |first41=Amin R. |last42=Jiang |first42=Rong-San |last43=Kennedy |first43=David |last44=Kern |first44=Robert |last45=Laidlaw |first45=Tanya |last46=Lal |first46=Devyani |last47=Lane |first47=Andrew |last48=Lee |first48=Heung-Man |last49=Lee |first49=Jivianne T. |last50=Levy |first50=Joshua M. |last51=Lin |first51=Sandra Y. |last52=Lund |first52=Valerie |last53=McMains |first53=Kevin C. |last54=Metson |first54=Ralph |last55=Mullol |first55=Joaquim |last56=Naclerio |first56=Robert |last57=Oakley |first57=Gretchen |last58=Otori |first58=Nobuyoshi |last59=Palmer |first59=James N. |last60=Parikh |first60=Sanjay R. |last61=Passali |first61=Desiderio |last62=Patel |first62=Zara |last63=Peters |first63=Anju |last64=Philpott |first64=Carl |last65=Psaltis |first65=Alkis J. |last66=Ramakrishnan |first66=Vijay R. |last67=Ramanathan |first67=Murugappan |last68=Roh |first68=Hwan-Jung |last69=Rudmik |first69=Luke |last70=Sacks |first70=Raymond |last71=Schlosser |first71=Rodney J. |last72=Sedaghat |first72=Ahmad R. |last73=Senior |first73=Brent A. |last74=Sindwani |first74=Raj |last75=Smith |first75=Kristine |last76=Snidvongs |first76=Kornkiat |last77=Stewart |first77=Michael |last78=Suh |first78=Jeffrey D. |last79=Tan |first79=Bruce K. |last80=Turner |first80=Justin H. |last81=Drunen |first81=Cornelis M. |last82=Voegels |first82=Richard |last83=Wang |first83=De Yun |last84=Woodworth |first84=Bradford A. |last85=Wormald |first85=Peter-John |last86=Wright |first86=Erin D. |last87=Yan |first87=Carol |last88=Zhang |first88=Luo |last89=Zhou |first89=Bing}}</ref><ref name="pmid18206715"/> A 2018 Cochrane review, however, found no evidence that people with symptoms lasting seven days or more before consulting their physician are more likely to have bacterial sinusitis as one study found that about 80% of patients have symptoms lasting more than 7 days and another about 70%.<ref name="pmid30198548"/> Antibiotics are specifically not recommended in those with mild / moderate disease during the first week of infection due to risk of adverse effects, [[antibiotic resistance]], and cost.<ref>{{cite journal | vauthors = Smith SR, Montgomery LG, Williams JW | title = Treatment of mild to moderate sinusitis | journal = Archives of Internal Medicine | volume = 172 | issue = 6 | pages = 510–3 | date = March 2012 | pmid = 22450938 | doi = 10.1001/archinternmed.2012.253 }}</ref>

[[Fluoroquinolones]], and a newer [[macrolide]] antibiotic such as [[clarithromycin]] or a [[tetracycline]] like [[doxycycline]], are used in those who have severe allergies to [[penicillin]]s.<ref>{{cite journal | vauthors = Karageorgopoulos DE, Giannopoulou KP, Grammatikos AP, Dimopoulos G, Falagas ME | title = Fluoroquinolones compared with beta-lactam antibiotics for the treatment of acute bacterial sinusitis: a meta-analysis of randomized controlled trials | journal = CMAJ | volume = 178 | issue = 7 | pages = 845–54 | date = March 2008 | pmid = 18362380 | pmc = 2267830 | doi = 10.1503/cmaj.071157 }}</ref> Because of increasing resistance to amoxicillin the 2012 guideline of the [[Infectious Diseases Society of America]] recommends amoxicillin-clavulanate as the initial treatment of choice for bacterial sinusitis.<ref name="pmid22438350">{{cite journal | vauthors = Chow AW, Benninger MS, Brook I, Brozek JL, Goldstein EJ, Hicks LA, Pankey GA, Seleznick M, Volturo G, Wald ER, File TM | title = IDSA clinical practice guideline for acute bacterial rhinosinusitis in children and adults | journal = Clinical Infectious Diseases | volume = 54 | issue = 8 | pages = e72–e112 | date = April 2012 | pmid = 22438350 | doi = 10.1093/cid/cir1043 | doi-access = free }}</ref> The guidelines also recommend against other commonly used antibiotics, including [[azithromycin]], [[clarithromycin]], and [[trimethoprim/sulfamethoxazole]], because of growing antibiotic resistance. The [[FDA]] recommends against the use of [[fluoroquinolone]]s when other options are available due to higher risks of serious [[side effect]]s.<ref>{{cite web|title=Fluoroquinolone Antibacterial Drugs: Drug Safety Communication – FDA Advises Restricting Use for Certain Uncomplicated Infections|url=https://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm500665.htm|website=FDA|access-date=16 May 2016|date=12 May 2016|archive-url=https://web.archive.org/web/20160516004228/https://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHumanMedicalProducts/ucm500665.htm|archive-date=16 May 2016}}</ref>

A short course (3–7 days) of antibiotics appears to be as effective as the typical longer course (10–14 days) of antibiotics for those with clinically diagnosed acute bacterial sinusitis without any other severe disease or complicating factors.<ref>{{cite journal | vauthors = Falagas ME, Karageorgopoulos DE, Grammatikos AP, Matthaiou DK | title = Effectiveness and safety of short vs. long duration of antibiotic therapy for acute bacterial sinusitis: a meta-analysis of randomized trials | journal = British Journal of Clinical Pharmacology | volume = 67 | issue = 2 | pages = 161–71 | date = February 2009 | pmid = 19154447 | pmc = 2670373 | doi = 10.1111/j.1365-2125.2008.03306.x }}</ref> The [[Infectious Diseases Society of America|IDSA]] guideline suggest five to seven days of antibiotics is long enough to treat a bacterial infection without encouraging resistance. The guidelines still recommend that children receive antibiotic treatment for ten days to two weeks.<ref name="pmid22438350"/>

===Corticosteroids===
For unconfirmed acute sinusitis, [[Nasal spray#Corticosteroid|nasal sprays]] using [[corticosteroid]]s are not better than a [[placebo]] either alone or in combination with antibiotics.<ref>{{cite journal | vauthors = Williamson IG, Rumsby K, Benge S, Moore M, Smith PW, Cross M, Little P | title = Antibiotics and topical nasal steroid for treatment of acute maxillary sinusitis: a randomized controlled trial | journal = JAMA | volume = 298 | issue = 21 | pages = 2487–96 | date = December 2007 | pmid = 18056902 | doi = 10.1001/jama.298.21.2487 | doi-access =  }}</ref> For cases confirmed by radiology or nasal endoscopy, treatment with intranasal corticosteroids alone or in combination with antibiotics is supported.<ref>{{cite journal | vauthors = Zalmanovici Trestioreanu A, Yaphe J | title = Intranasal steroids for acute sinusitis | journal = The Cochrane Database of Systematic Reviews | volume = 12 | issue = 12 | date = December 2013 | pmid = 24293353 | pmc = 6698484 | doi = 10.1002/14651858.CD005149.pub4 }}</ref> The benefit, however, is small.<ref>{{cite journal | vauthors = Hayward G, Heneghan C, Perera R, Thompson M | title = Intranasal corticosteroids in management of acute sinusitis: a systematic review and meta-analysis | journal = Annals of Family Medicine | volume = 10 | issue = 3 | pages = 241–9 | year = 2012 | pmid = 22585889 | pmc = 3354974 | doi = 10.1370/afm.1338 }}</ref>

For confirmed chronic rhinosinusitis, there is limited evidence that intranasal steroids improve symptoms and insufficient evidence that one type of steroid is more effective.<ref>{{cite journal | vauthors = Chong LY, Head K, Hopkins C, Philpott C, Schilder AG, Burton MJ | title = Intranasal steroids versus placebo or no intervention for chronic rhinosinusitis | journal = The Cochrane Database of Systematic Reviews | volume = 2016 | date = April 2016 | issue = 4 | pmid = 27115217 | doi = 10.1002/14651858.cd011996.pub2 | pmc = 9393647 | s2cid = 205210710 | url = https://kclpure.kcl.ac.uk/portal/en/publications/intranasal-steroids-versus-placebo-or-no-intervention-for-chronic-rhinosinusitis(281bb1c8-9c9a-4d27-adde-37f93e7bf7fc).html | access-date = 2019-11-15 | archive-date = 2019-11-15 | archive-url = https://web.archive.org/web/20191115193627/https://kclpure.kcl.ac.uk/portal/en/publications/intranasal-steroids-versus-placebo-or-no-intervention-for-chronic-rhinosinusitis(281bb1c8-9c9a-4d27-adde-37f93e7bf7fc).html | url-status = live }}</ref><ref>{{cite journal | vauthors = Chong LY, Head K, Hopkins C, Philpott C, Burton MJ, Schilder AG | title = Different types of intranasal steroids for chronic rhinosinusitis | journal = The Cochrane Database of Systematic Reviews | volume = 2016 | date = April 2016 | issue = 4 | pmid = 27115215 | doi = 10.1002/14651858.cd011993.pub2 | pmc = 8939045 | s2cid = 205210689 }}</ref>

There is only limited evidence to support short treatment with corticosteroids by mouth for chronic rhinosinusitis with nasal polyps.<ref>{{cite journal | vauthors = Head K, Chong LY, Hopkins C, Philpott C, Burton MJ, Schilder AG | title = Short-course oral steroids alone for chronic rhinosinusitis | journal = The Cochrane Database of Systematic Reviews | volume = 2016 | date = April 2016 | issue = 4 | pmid = 27113367 | doi = 10.1002/14651858.cd011991.pub2 | pmc = 8504433 }}</ref><ref name="pmid17844873">{{cite journal | vauthors = Fokkens W, Lund V, Mullol J | title = European position paper on rhinosinusitis and nasal polyps 2007 | journal = Rhinology. Supplement | volume = 20 | issue = 1 | pages = 1–136 | year = 2007 | pmid = 17844873 | doi = 10.1017/S0959774306000060 | s2cid = 35987497 }}</ref><ref>{{cite journal | vauthors = Thomas M, Yawn BP, Price D, Lund V, Mullol J, Fokkens W | title = EPOS Primary Care Guidelines: European Position Paper on the Primary Care Diagnosis and Management of Rhinosinusitis and Nasal Polyps 2007 - a summary | journal = Primary Care Respiratory Journal | volume = 17 | issue = 2 | pages = 79–89 | date = June 2008 | pmid = 18438594 | pmc = 6619880 | doi = 10.3132/pcrj.2008.00029 }}</ref> There is limited evidence to support corticosteroids by mouth in combination with antibiotics for acute sinusitis; it has only short-term effect improving the symptoms.<ref>{{cite journal | vauthors = Venekamp RP, Thompson MJ, Hayward G, Heneghan CJ, Del Mar CB, Perera R, Glasziou PP, Rovers MM | title = Systemic corticosteroids for acute sinusitis | journal = The Cochrane Database of Systematic Reviews | issue = 3 | date = March 2014 | pmid = 24664368 | doi = 10.1002/14651858.CD008115.pub3 | pmc = 11179165 | url = https://pure.bond.edu.au/ws/files/32844104/Systemic_corticosteroids_for_acute_sinusitis.pdf | access-date = 2019-11-15 | archive-date = 2019-11-15 | archive-url = https://web.archive.org/web/20191115193635/https://pure.bond.edu.au/ws/files/32844104/Systemic_corticosteroids_for_acute_sinusitis.pdf | url-status = live }}</ref><ref>{{cite journal | vauthors = Head K, Chong LY, Hopkins C, Philpott C, Schilder AG, Burton MJ | title = Short-course oral steroids as an adjunct therapy for chronic rhinosinusitis | journal = The Cochrane Database of Systematic Reviews | volume = 2016 | date = April 2016 | issue = 4 | pmid = 27115214 | doi = 10.1002/14651858.cd011992.pub2 | pmc = 8763342 | s2cid = 205210682 }}</ref>

===Surgery===
For sinusitis of dental origin, treatment focuses on removing the infection and preventing reinfection by removing the [[microorganism]]s, their byproducts, and pulpal debris from the infected [[root canal]].<ref name="American Association of Endodontists-2018"/> Systemic [[antibiotic]]s are ineffective as a definitive solution. They may afford temporary relief of symptoms by improving sinus clearing. They may be appropriate for rapidly spreading infections, but [[debridement]] and disinfection of the root canal system at the same time are necessary. Treatment options include non-surgical [[root canal treatment]], [[periradicular surgery]], [[tooth replantation]], or extraction of the infected tooth.<ref name="American Association of Endodontists-2018">{{cite web |title=Maxillary Sinusitis of Endodontic Origin |url=https://www.aae.org/specialty/wp-content/uploads/sites/2/2018/04/AAE_PositionStatement_MaxillarySinusitis.pdf |website=American Association of Endodontists |access-date=26 March 2019 |date=2018 |archive-date=26 March 2019 |archive-url=https://web.archive.org/web/20190326020125/https://www.aae.org/specialty/wp-content/uploads/sites/2/2018/04/AAE_PositionStatement_MaxillarySinusitis.pdf |url-status=live }}</ref>

For chronic or recurring sinusitis, referral to an [[Otolaryngology|otolaryngologist]] may be indicated, and treatment options may include nasal surgery. Surgery should only be considered for those people who do not benefit with medication or have non-invasive fungal sinusitis<ref>{{cite web |last=Meghanadh |first=Dr Koralla Raja |date=2022-12-16 |title=Fungal sinusitis - causes, symptoms, and treatment |url=https://www.medyblog.com/post/fungal-sinusitis-causes-symptoms-treatment-noninvasive |access-date=2023-05-05 |website=Medy Blog |language=en |archive-date=2023-05-05 |archive-url=https://web.archive.org/web/20230505104623/https://www.medyblog.com/post/fungal-sinusitis-causes-symptoms-treatment-noninvasive |url-status=live }}{{Unreliable medical source|date=February 2024}}</ref>{{Unreliable medical source|date=February 2024}}.<ref name="pmid17844873"/><ref>{{cite web |url=http://www.sinuses.com/faq.htm#surgery |title=FAQ — Sinusitis |access-date=2007-10-28 | vauthors = Tichenor WS |date=2007-04-22 |url-status=live |archive-url=https://web.archive.org/web/20071101052144/http://www.sinuses.com/faq.htm#surgery |archive-date=2007-11-01 }}</ref> It is unclear how benefits of surgery compare to medical treatments in those with nasal polyps as this has been poorly studied.<ref>{{cite journal | vauthors = Rimmer J, Fokkens W, Chong LY, Hopkins C | title = Surgical versus medical interventions for chronic rhinosinusitis with nasal polyps | journal = The Cochrane Database of Systematic Reviews | volume = 2014 | issue = 12 | date = 1 December 2014 | pmid = 25437000 | doi = 10.1002/14651858.CD006991.pub2 | pmc = 11193160 }}</ref><ref>{{cite journal | vauthors = Sharma R, Lakhani R, Rimmer J, Hopkins C | title = Surgical interventions for chronic rhinosinusitis with nasal polyps | journal = The Cochrane Database of Systematic Reviews | issue = 11 | date = November 2014 | volume = 2014 | pmid = 25410644 | doi = 10.1002/14651858.cd006990.pub2 | pmc = 11166467 }}</ref>

Several surgical approaches can be used to access the sinuses, and these have generally shifted from external/extranasal approaches to intranasal [[endoscopic]] ones.  The benefit of [[functional endoscopic sinus surgery]] (FESS) is its ability to allow for a more targeted approach to the affected sinuses, reducing tissue disruption and minimizing post-operative complications.<ref>{{cite journal | vauthors = Stammberger H | title = Endoscopic endonasal surgery--concepts in treatment of recurring rhinosinusitis. Part I. Anatomic and pathophysiologic considerations | journal = Otolaryngology–Head and Neck Surgery | volume = 94 | issue = 2 | pages = 143–7 | date = February 1986 | pmid = 3083326 | doi = 10.1177/019459988609400202 | s2cid = 34575985 }}</ref> However, if a traditional FESS with Messerklinger technique is followed the success rate will be as low as 30%, 70% of the patients tend to have recurrence within 3 years.<ref name="Medyblog-Meghanadh-2023">{{cite web |last=Meghanadh |first=Dr Koralla Raja |date=2023-02-07 |title=Sinusitis Surgery: An Overview of the Different Technologies |url=https://www.medyblog.com/post/sinusitis-surgery-types-fess-endoscopic-tfse-debriders-navigation-guided-balloon-sinuplasty |access-date=2023-05-05 |website=Medy Blog |language=en |archive-date=2023-05-05 |archive-url=https://web.archive.org/web/20230505101613/https://www.medyblog.com/post/sinusitis-surgery-types-fess-endoscopic-tfse-debriders-navigation-guided-balloon-sinuplasty |url-status=live }}{{Unreliable medical source|date=February 2024}}</ref>{{Unreliable medical source|date=February 2024}} On the other hand with use of TFSE technique along with navigation system, debriders and balloon sinuplasty or EBS can give a success rate of over 99.9%.<ref name="Medyblog-Meghanadh-2023" />{{Unreliable medical source|date=February 2024}} The use of [[Bioresorbable stents|drug eluting stents]] such as [[propel mometasone furoate implant]] may help in recovery after surgery.<ref>{{cite journal | vauthors = Liang J, Lane AP | title = Topical Drug Delivery for Chronic Rhinosinusitis | journal = Current Otorhinolaryngology Reports | volume = 1 | issue = 1 | pages = 51–60 | date = March 2013 | pmid = 23525506 | pmc = 3603706 | doi = 10.1007/s40136-012-0003-4 }}</ref>

Another recently developed treatment is [[balloon sinuplasty]]. This method, similar to [[balloon angioplasty]] used to "unclog" arteries of the heart, utilizes balloons in an attempt to expand the openings of the sinuses in a less invasive manner.<ref name="pmid21735433" /> The effectiveness of the functional endoscopic balloon dilation approach compared to conventional FESS is not known.<ref name="pmid21735433" />

[[Histopathology]] of sinonasal contents removed from surgery can be diagnostically valuable:
<gallery mode="packed" heights="150">
File:Histopathology of sinonasal inflammatory polyp with mixed inflammation, annotated.jpg|'''Benign chronic mixed inflammation''' of an inflammatory sinonasal polyp
File:Histopathology of acute sinusitis.png|'''Acute inflammation''' characterized by [[neutrophil]]s
File:Histopathology of extranodal NK-T cell lymphoma, nasal type.png|'''[[Extranodal NK/T cell lymphoma, nasal type]]'''.<ref>{{cite journal| author=Takahara M, Kumai T, Kishibe K, Nagato T, Harabuchi Y| title=Extranodal NK/T-Cell Lymphoma, Nasal Type: Genetic, Biologic, and Clinical Aspects with a Central Focus on Epstein-Barr Virus Relation. | journal=Microorganisms | year= 2021 | volume= 9 | issue= 7 | page=1381 | pmid=34202088 | doi=10.3390/microorganisms9071381 | doi-access=free | pmc=8304202 }}<br />- "This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/ {{Webarchive|url=https://web.archive.org/web/20171016050101/https://creativecommons.org/licenses/by/4.0/ |date=2017-10-16 }})."</ref> It may be incidentally discovered in people undergoing surgery for sinusitis.<ref name="pmid28652944">{{cite journal| author=Althoff A, Bibliowicz M| title=Extranodal Natural Killer/T-Cell Lymphoma: An Incidental Finding. | journal=Cureus | year= 2017 | volume= 9 | issue= 5 | article-number= e1260 | pmid=28652944 | doi=10.7759/cureus.1260 | doi-access=free | pmc=5476476 }}</ref> 
</gallery>

===Treatments directed to rhinovirus infection===
A study has shown that patients given a spray formulation of 0.73&nbsp;mg of Tremacamra (a soluble intercellular adhesion molecule 1 [ICAM-1] receptor) reduced the severity of illness.<ref>{{Cite journal |last1=Turner |first1=Ronald B. |last2=Wecker |first2=Margaret T. |last3=Pohl |first3=Gerhardt |last4=Witek |first4=Theodore J. |last5=McNally |first5=Eugene |last6=St. George |first6=Roger |last7=Winther |first7=Birgit |last8=Hayden |first8=Frederick G. |date=1999-05-19 |title=Efficacy of Tremacamra, a Soluble Intercellular Adhesion Molecule 1, for Experimental Rhinovirus Infection: A Randomized Clinical Trial |url=https://jamanetwork.com/journals/jama/fullarticle/189972 |journal=JAMA |volume=281 |issue=19 |pages=1797–1804 |doi=10.1001/jama.281.19.1797 |issn=0098-7484|url-access=subscription }}</ref><ref name="pmid31430424"/>

==Prognosis==
A 2018 review has found that without the use of antibiotics, about 46% were cured after one week and 64% after two weeks.<ref name="pmid30198548">{{cite journal |vauthors=Lemiengre MB, van Driel ML, Merenstein D, Liira H, Mäkelä M, De Sutter AI |title=Antibiotics for acute rhinosinusitis in adults |journal=Cochrane Database Syst Rev |volume=2018 |article-number=CD006089 |date=September 2018 |issue=9 |pmid=30198548 |pmc=6513448 |doi=10.1002/14651858.CD006089.pub5 }}</ref>

==Epidemiology==
Sinusitis is a common condition, with an estimated 24 to 31 million cases occurring annually in the United States.<ref>{{cite journal | vauthors = Anon JB | title = Upper respiratory infections | journal = The American Journal of Medicine | volume = 123 | issue = 4 Suppl | pages = S16-25 | date = April 2010 | pmid = 20350632 | doi = 10.1016/j.amjmed.2010.02.003 }}</ref><ref>{{cite journal | vauthors = Dykewicz MS, Hamilos DL | title = Rhinitis and sinusitis | journal = The Journal of Allergy and Clinical Immunology | volume = 125 | issue = 2 Suppl 2 | pages = S103-15 | date = February 2010 | pmid = 20176255 | doi = 10.1016/j.jaci.2009.12.989 }}</ref> Chronic sinusitis affects approximately 12.5% of people.<ref name="pmid21890184"/>

==Research==
Based on recent theories on the role that [[fungi]] may play in the development of chronic sinusitis, [[antifungal|antifungal treatments]] have been used, on a trial basis. These trials have had mixed results.<ref name="pmid18206715"/>

== See also ==
* [[Fungal sinusitis]]
* [[Odontogenic sinusitis]]

== References ==
{{Reflist}}

== External links ==
{{Medical condition classification and resources
| DiseasesDB      = 12136
| ICD11           = {{ICD11|CA01}}, {{ICD11|CA0A}}
| ICD10           = {{ICD10|J|01||j|00}}, {{ICD10|J|32||j|30}}
| ICD9            = {{ICD9|461}}, {{ICD9|473}}
| ICDO            =
| OMIM            =
| MedlinePlus     = 000647
| eMedicineSubj   = article
| eMedicineTopic  = 232670
| MeshID          = D012852
| SNOMED CT       = 36971009
}}
* {{cite web | url = https://medlineplus.gov/sinusitis.html | publisher = U.S. National Library of Medicine | work = MedlinePlus | title = Sinusitis }}

{{Respiratory pathology}}
{{Common Cold}}

{{Authority control}}

[[Category:Nose disorders]]
[[Category:Headaches]]
[[Category:Inflammations]]
[[Category:Wikipedia medicine articles ready to translate]]
[[Category:Wikipedia emergency medicine articles ready to translate]]
[[Category:Rhinology]]