View source for Bronchiectasis

{{Short description|Permanent enlargement of the lung airways}}
{{Use dmy dates|date=August 2025}}
{{cs1 config|name-list-style=vanc|display-authors=6}}
{{Infobox medical condition (new)
| name          = Bronchiectasis
| synonyms      =
| image         = Bronchiectasis NHLBI.jpg
| alt           =
| caption       = Figure A shows a cross-section of the lungs with normal airways and widened airways. Figure B shows a cross-section of a normal airway. Figure C shows a cross-section of an airway with bronchiectasis.
| pronounce     = {{IPAc-en|ˌ|b|r|ɒ|ŋ|k|ɪ|ˈ|ɛ|k|t|ə|s|ɪ|s}}<ref>{{Cite web|url=https://www.lexico.com/en/definition/bronchiectasis|archive-url=https://web.archive.org/web/20191109175656/https://www.lexico.com/en/definition/bronchiectasis|archive-date=9 November 2019|title=Bronchiectasis &#124; Definition of Bronchiectasis by Lexico|website=Lexico Dictionaries &#124; English}}</ref>
| field         = [[Pulmonology]]
| symptoms      = Productive cough, [[shortness of breath]], chest pain<ref name=NIH2014Sign/><ref name=Mc2013/>
| onset         = Gradual<ref>{{cite journal|last1=Maguire|first1=G|title=Bronchiectasis – a guide for primary care.|journal=Australian Family Physician|date=November 2012|volume=41|issue=11|pages=842–50|pmid=23145413}}</ref>
| duration      = Long term<ref name=NIH2014What/>
| causes        = Infections, [[cystic fibrosis]], other genetic conditions, [[idiopathic]]<ref name=Mc2013/><ref name=Stat2019>{{cite journal |last1=Bird |first1=K |last2=Memon |first2=J |title=Bronchiectasis |date=January 2019 |journal=StatPearls [Internet] |pmid=28613561 |id=NBK430810 }}</ref>
| risks         =
| diagnosis     = Based on symptoms, [[CT scan]]<ref name=BTS2012/>
| differential  = [[Chronic obstructive pulmonary disease]], [[Asbestosis]], [[Tracheobronchomalacia]]
| treatment     = [[Antibiotic]]s, [[bronchodilator]]s, [[lung transplant]]<ref name=Mc2013/><ref name=NIH2014Tx/><ref name=Cor2013/>
| medication    =
| frequency     = 1–250 per 250,000 adults<ref name=Cot2015/>
| deaths        =
}}
<!-- Definition and symptoms -->

'''Bronchiectasis''' is a disease in which there is permanent enlargement of parts of the [[bronchi|airways]] of the [[lung]].<ref name=NIH2014What>{{cite web|title=What Is Bronchiectasis?|url=https://www.nhlbi.nih.gov/health/health-topics/topics/brn|website=NHLBI|access-date=10 August 2016|date=2 June 2014|archive-url=https://web.archive.org/web/20160810235340/http://www.nhlbi.nih.gov/health/health-topics/topics/brn/|archive-date=10 August 2016}}</ref> Symptoms typically include a chronic cough with [[sputum|mucus]] production.<ref name=Mc2013>{{cite journal|last1=McShane|first1=PJ|last2=Naureckas|first2=ET|last3=Tino|first3=G|last4=Strek|first4=ME|title=Non-cystic fibrosis bronchiectasis.|journal=American Journal of Respiratory and Critical Care Medicine|date=15 September 2013|volume=188|issue=6|pages=647–56|pmid=23898922|doi=10.1164/rccm.201303-0411CI}}</ref> Other symptoms include [[shortness of breath]], [[hemoptysis|coughing up blood]], and chest pain.<ref name=NIH2014Sign>{{cite web|title=What Are the Signs and Symptoms of Bronchiectasis?|url=https://www.nhlbi.nih.gov/health/health-topics/topics/brn/signs|website=NHLBI|access-date=10 August 2016|date=2 June 2014|archive-url=https://web.archive.org/web/20160823030732/https://www.nhlbi.nih.gov/health/health-topics/topics/brn/signs|archive-date=23 August 2016}}</ref> Wheezing and [[nail clubbing]] may also occur.<ref name=NIH2014Sign/> Those with the disease often get [[lung infection]]s.<ref name=NIH2014Tx>{{cite web|title=How Is Bronchiectasis Treated?|url=https://www.nhlbi.nih.gov/health/health-topics/topics/brn/treatment|website=NHLBI|access-date=10 August 2016|date=2 June 2014|archive-url=https://web.archive.org/web/20160728042454/http://www.nhlbi.nih.gov/health/health-topics/topics/brn/treatment|archive-date=28 July 2016}}</ref>

<!-- Cause and Diagnosis -->
Bronchiectasis may result from a number of [[infection|infectious]] and acquired causes, including [[measles]],<ref>{{cite news|work = Sydney Morning Herald|access-date=9 August 2022|title=Durham's voice stays pure despite the blows|date=22 April 2010|url=https://www.smh.com.au/national/durhams-voice-stays-pure-despite-the-blows-20100421-szzp.html|archive-url=https://web.archive.org/web/20220809145953/https://www.smh.com.au/national/durhams-voice-stays-pure-despite-the-blows-20100421-szzp.html|archive-date=9 August 2022}}</ref> [[pneumonia]], [[tuberculosis]], [[immune system]] problems, as well as the genetic disorder [[cystic fibrosis]].<ref>{{Cite journal|last1=José|first1=R. J.|last2=Brown|first2=J. S.|date=2014|title=Bronchiectasis|journal= British Journal of Hospital Medicine|volume=75|issue=Suppl 10:C146–51|pages=C146–C151|doi=10.12968/hmed.2014.75.Sup10.C146|pmid=25289486}}</ref><ref name=Mc2013/><ref name=DAVIDSONS2010>{{cite book |editor1=Nicki R. Colledge |editor2=Brian R. Walker |editor3=Stuart H. Ralston |others=illustrated by Robert Britton |title=Davidson's principles and practice of medicine. |year=2010 |publisher=Churchill Livingstone/Elsevier |location=Edinburgh |isbn=978-0-7020-3085-7 |edition=21st}}</ref> Cystic fibrosis eventually results in severe bronchiectasis in nearly all cases.<ref>{{cite book|editor-last1=Brant|editor-first1=William E.|editor-last2=Helms|editor-first2=Clyde A.|title=Fundamentals of diagnostic radiology|date=2006|publisher=Lippincott Williams & Wilkins|location=Philadelphia|isbn=978-0-7817-6135-2|page=518|edition=3rd|url=https://books.google.com/books?id=Sossht2t5XwC&pg=PA518|url-status=live|archive-url=https://web.archive.org/web/20170906121052/https://books.google.com/books?id=Sossht2t5XwC&pg=PA518|archive-date=6 September 2017}}</ref> The cause in 10–50% of those without cystic fibrosis is unknown.<ref name=Mc2013/> The mechanism of disease is breakdown of the airways due to an excessive inflammatory response.<ref name=Mc2013/> Involved airways ([[bronchi]]) become enlarged and thus less able to clear secretions.<ref name=Mc2013/> These secretions increase the amount of [[bacteria]] in the lungs, resulting in airway blockage and further breakdown of the airways.<ref name=Mc2013/> It is classified as an [[obstructive lung disease]], along with [[chronic obstructive pulmonary disease]] and [[asthma]].<ref>{{cite book|author=Michael Filbin|author2=Lisa M. Lee|first3=Brian L.|last3=Shaffer|title=Blueprints pathophysiology II : pulmonary, gastrointestinal, and rheumatology: notes & cases|date=2003|publisher=Blackwell Pub.|location=Malden, Mass.|isbn=978-1-4051-0351-0|page=12|edition=1st|url=https://books.google.com/books?id=9QuInLjbHn0C&pg=PA12|url-status=live|archive-url=https://web.archive.org/web/20170906121052/https://books.google.com/books?id=9QuInLjbHn0C&pg=PA12|archive-date=6 September 2017}}</ref> The diagnosis is suspected based on symptoms and confirmed using [[computed tomography]].<ref name=BTS2012>{{cite web|title=Quality Standards for Clinically Significant Bronchiectasis in Adults|url=https://www.brit-thoracic.org.uk/standards-of-care/quality-standards/bts-bronchiectasis-quality-standards/|publisher=British Thoracic Society|access-date=29 April 2017|date=July 2012|archive-url=https://web.archive.org/web/20170707001137/https://www.brit-thoracic.org.uk/standards-of-care/quality-standards/bts-bronchiectasis-quality-standards/|archive-date=7 July 2017}}</ref> [[Sputum culture|Cultures of the mucus]] produced may be useful to determine treatment in those who have acute worsening and at least once a year.<ref name=BTS2012/>

<!-- Treatment and Prognosis-->
Periods of worsening may occur due to infection.<ref name=NIH2014Tx/> In these cases, [[antibiotics]] are recommended.<ref name=NIH2014Tx/> Common antibiotics used include [[amoxicillin]], [[erythromycin]], or [[doxycycline]].<ref>{{cite book|last1=Brent|first1=Andrew|last2=Davidson|first2=Robert|last3=Seale|first3=Anna|title=Oxford Handbook of Tropical Medicine|date=2014|publisher=OUP Oxford|isbn=978-0-19-150307-8|page=223|url=https://books.google.com/books?id=jFpuAwAAQBAJ&pg=PA223|url-status=live|archive-url=https://web.archive.org/web/20160821102652/https://books.google.ca/books?id=jFpuAwAAQBAJ&pg=PA223|archive-date=21 August 2016}}</ref> Antibiotics, such as erythromycin, may also be used to prevent worsening of disease.<ref name=Mc2013/><ref name=Qi2014>{{Cite journal|last1=Wu|first1=Qibiao|last2=Shen|first2=Weixing|last3=Cheng|first3=Haibo|last4=Zhou|first4=Xiqiao|date=April 2014|title=Long-term macrolides for non-cystic fibrosis bronchiectasis: a systematic review and meta-analysis|journal=Respirology|volume=19|issue=3|pages=321–9|doi=10.1111/resp.12233 |pmid=24417869|s2cid=2567740|doi-access=free}}</ref> [[#Airway clearance|Airway clearance]] techniques, a type of [[physical therapy]], are also recommended.<ref name=Lee2015>{{cite journal|last1=Lee|first1=AL|last2=Burge|first2=AT|last3=Holland|first3=AE|title=Airway clearance techniques for bronchiectasis.|journal=The Cochrane Database of Systematic Reviews|date=23 November 2015|volume=2015 |issue=11|article-number=CD008351|pmid=26591003|doi=10.1002/14651858.CD008351.pub3|pmc=7175838}}</ref> [[Bronchodilator|Medications to dilate the airway]]s and inhaled [[Corticosteroid|steroids]] may be used during sudden worsening, but there are no studies to determine effectiveness.<ref name=Mc2013/><ref name=":3">{{Cite journal|last1=Kapur|first1=Nitin|last2=Petsky|first2=Helen L.|last3=Bell|first3=Scott|last4=Kolbe|first4=John|last5=Chang|first5=Anne B.|date=16 May 2018|title=Inhaled corticosteroids for bronchiectasis|journal=The Cochrane Database of Systematic Reviews|volume=2018|issue=5|article-number=CD000996|doi=10.1002/14651858.CD000996.pub3 |pmc=6494510|pmid=29766487}}</ref> There are also no studies on the use of inhaled [[Corticosteroid|steroids]] in children.<ref name=":3" /> Surgery, while commonly done, has not been well studied.<ref>{{cite journal|last1=Corless|first1=JA|last2=Warburton|first2=CJ|s2cid=72965871|title=Surgery vs non-surgical treatment for bronchiectasis.|journal=The Cochrane Database of Systematic Reviews|date=2000|volume=2000 |issue=4|article-number=CD002180|doi=10.1002/14651858.CD002180|pmid=11034745|pmc=8407459}}</ref><ref name=Mc2013/> [[Lung transplantation]] may be an option in those with very severe disease.<ref name=Cor2013>{{cite journal|last1=Corris|first1=PA|title=Lung transplantation for cystic fibrosis and bronchiectasis.|journal=Seminars in Respiratory and Critical Care Medicine|date=Jun 2013|volume=34|issue=3|pages=297–304|pmid=23821505|doi=10.1055/s-0033-1348469|s2cid=32614762 }}</ref>

<!-- Epidemiology and History -->
The disease affects between 1 per 1000 and 1 per 250,000 adults.<ref name=Cot2015>{{cite book|last1=Cottin|first1=Vincent|last2=Cordier|first2=Jean-Francois|last3=Richeldi|first3=Luca|title=Orphan Lung Diseases: A Clinical Guide to Rare Lung Disease|date=2015|publisher=Springer|isbn=978-1-4471-2401-6|page=30|url=https://books.google.com/books?id=U-InBgAAQBAJ&pg=PA30|url-status=live|archive-url=https://web.archive.org/web/20160821104334/https://books.google.ca/books?id=U-InBgAAQBAJ&pg=PA30|archive-date=21 August 2016}}</ref> The disease is more common in women and increases as people age.<ref name=Mc2013/> It became less common since the 1950s with the introduction of antibiotics.<ref name=Cot2015/> It is more common among certain ethnic groups (such as [[indigenous people]] in the US).<ref name=Cot2015/> It was first described by [[René Laennec]] in 1819.<ref name=Mc2013/> The economic costs in the United States are estimated at $630 million per year.<ref name=Mc2013/>

==Signs and symptoms==
[[File:Depiction of a person suffering from Bronchiectasis.png|thumb|upright=1.3|The typical symptoms of bronchiectasis are shown. Also, the change in bronchi under bronchiectasis are illustrated.]]

Symptoms of bronchiectasis commonly include a cough productive of frequent green or yellow [[sputum]] lasting months to years.<ref name="Mc2013" /> Other common symptoms include [[Shortness of breath|difficulty breathing]], [[Wheeze|wheezing]] (a whistling sound when you breathe), and [[chest pain]]. Exacerbations of symptoms may occur; these exacerbations occur more frequently in advanced or severe disease.<ref name="O'Donnell NEJM" /> Systemic symptoms, including fevers, chills, night sweats, fatigue and weight loss may be seen with bronchiectasis.<ref name="O'Donnell NEJM" /> Bronchiectasis may also present with [[hemoptysis|coughing up blood]] in the absence of sputum, which has been called "dry bronchiectasis."

Exacerbations in bronchiectasis present as a worsening of cough, increasing sputum volume or thickened consistency lasting at least 48 hours, worsening shortness of breath (breathlessness), worsening exercise intolerance, increased fatigue or [[malaise]], and the development of hemoptysis.<ref name="O'Donnell NEJM" />

People often report frequent bouts of "bronchitis" requiring therapy with repeated courses of antibiotics. People with bronchiectasis may have [[bad breath]] from active infection. On examination, [[Crackles|crepitations]] and expiratory [[rhonchi]] may be heard with auscultation. [[Nail clubbing]] is a rare symptom.<ref name="Mc2013" />

The complications of bronchiectasis include serious health conditions, such as [[respiratory failure]] and [[atelectasis]]:
collapse or closure of a lung. Respiratory failure occurs when not enough oxygen passes from the lungs into the blood.<ref name=":4">{{Cite web|url=https://www.nhlbi.nih.gov/health/bronchiectasis|title=Bronchiectasis |work=National Heart, Lung, and Blood Institute (NHLBI) |date=24 March 2022 |publisher=US National Library of Medicine}} {{PD-notice}}</ref> Atelectasis occur when one or more segments of the lungs collapse or do not inflate properly. Other pulmonary complications include lung [[abscess]] and [[empyema]]. Cardiovascular complications include [[Pulmonary heart disease|cor pulmonale]], in which there is enlargement and failure of the right side of the heart as a result of disease of the lungs.<ref>{{EMedicine|article|296961|Bronchiectasis: Practice Essentials, Background, Pathophysiology|}}</ref>

==Causes==
{| class="wikitable sortable" style="float: right; margin-left:15px; text-align:center"
!Category
!Causes
|-
|Autoimmune disease
|[[Rheumatoid arthritis]]
[[Sjögren's disease]]
|-
|Impaired host defenses
|[[Cystic fibrosis]]
[[Primary ciliary dyskinesia]]

[[Primary immunodeficiency]]

[[HIV/AIDS]]

[[Job's syndrome]]
|-
|Post-infective
|[[Bacterial pneumonia]]
[[Mycobacterium]] infection

[[Virus|Viral]] infection
|-
|Congenital
|[[Tracheobronchomegaly]]
[[Marfan syndrome]]

[[Williams–Campbell syndrome]]

[[Young's syndrome]]

[[Alpha-1 antitrypsin deficiency]]
|-
|Hypersensitivity
|[[Allergic bronchopulmonary aspergillosis]]
|-
|Inflammatory bowel disease
|[[Ulcerative colitis]]
[[Crohn's disease]]
|-
|Malignancy
|[[Chronic lymphocytic leukemia]]
[[Graft-versus-host disease]]
|-
|Obstruction
|[[Tumor]]
[[Foreign body aspiration]]

[[Lymphadenopathy]]
|-
|Other
|[[Pneumonia]]
Chronic [[Pulmonary aspiration|aspiration]]

[[Ammonia]] inhalation

[[Smoke inhalation]]

[[Radiation]]-induced lung disease

[[Yellow nail syndrome]]
|}
There are many causes that can induce or contribute to the development of bronchiectasis. The frequency of these different causes varies with geographic location.<ref name="auto">{{Cite journal|last1=McShane|first1=Pamela J.|last2=Naureckas|first2=Edward T.|last3=Strek|first3=Mary E.|date=July 2012|title=Bronchiectasis in a diverse US population: effects of ethnicity on etiology and sputum culture|journal=Chest|volume=142|issue=1|pages=159–167|doi=10.1378/chest.11-1024 |pmid=22267679}}</ref> [[Cystic fibrosis]] (CF) is identified as a cause in up to half of cases.<ref name=Mc2013/> Bronchiectasis without CF is known as non-CF bronchiectasis. Historically, about half of all cases of non-CF bronchiectasis were found to be [[Idiopathic disease|idiopathic]], or without a known cause.<ref>{{Cite journal|last1=Gao|first1=Yong-Hua|last2=Guan|first2=Wei-Jie|last3=Liu|first3=Shao-Xia|last4=Wang|first4=Lei|last5=Cui|first5=Juan-Juan|last6=Chen|first6=Rong-Chang|last7=Zhang|first7=Guo-Jun|date=November 2016|title=Aetiology of bronchiectasis in adults: A systematic literature review|journal=Respirology|volume=21|issue=8|pages=1376–83|doi=10.1111/resp.12832 |pmid=27321896|doi-access=free}}</ref> However, more recent studies with a more thorough [[Medical diagnosis|diagnostic]] work-up have found an etiology in 60–90% of patients.<ref name="auto" /><ref>{{Cite journal|last1=Lonni|first1=Sara|last2=Chalmers|first2=James D.|last3=Goeminne|first3=Pieter C.|last4=McDonnell|first4=Melissa J.|last5=Dimakou|first5=Katerina|last6=De Soyza|first6=Anthony|last7=Polverino|first7=Eva|last8=Van de Kerkhove|first8=Charlotte|last9=Rutherford|first9=Robert|last10=Davison|first10=John|last11=Rosales|first11=Edmundo|date=December 2015|title=Etiology of Non-Cystic Fibrosis Bronchiectasis in Adults and Its Correlation to Disease Severity|journal=Annals of the American Thoracic Society|volume=12|issue=12|pages=1764–70|doi=10.1513/AnnalsATS.201507-472OC |pmc=5467084|pmid=26431397}}</ref><ref>{{Cite journal|last1=Brower|first1=Kelly S.|last2=Del Vecchio|first2=Michael T.|last3=Aronoff|first3=Stephen C.|date=10 December 2014|title=The etiologies of non-CF bronchiectasis in childhood: a systematic review of 989 subjects|journal=BMC Pediatrics|volume=14|page=4|doi=10.1186/s12887-014-0299-y |pmc=4275950|pmid=25492164 |doi-access=free }}</ref>

=== Cystic fibrosis ===
[[Cystic fibrosis]] is the most common life-threatening autosomal recessive disease in the United States and Europe.<ref name="auto3">{{Cite journal|last1=Rowe|first1=Steven M.|last2=Miller|first2=Stacey|last3=Sorscher|first3=Eric J.|date=12 May 2005|title=Cystic Fibrosis|journal=New England Journal of Medicine|volume=352|issue=19|pages=1992–2001|doi=10.1056/NEJMra043184|pmid=15888700 }}</ref> It is a [[genetic disorder]] that affects the [[lungs]], but also the [[pancreas]], [[liver]], [[kidneys]], and [[intestine]].<ref>{{Cite journal|last1=O'Sullivan|first1=Brian P.|last2=Freedman|first2=Steven D.|date=30 May 2009|title=Cystic fibrosis|journal=Lancet|volume=373|issue=9678|pages=1891–1904|doi=10.1016/S0140-6736(09)60327-5 |pmid=19403164|s2cid=46011502}}</ref> It is caused by mutations in the [[Cftr|CFTR protein]], a [[chloride channel]] expressed in epithelial cells.<ref name="auto3" /> Lung disease results from clogging of the airways due to mucus build-up, decreased [[mucociliary clearance]], and resulting [[inflammation]].<ref>{{Cite journal|last=Elborn|first=J. Stuart|date=19 November 2016|title=Cystic fibrosis|journal=Lancet|volume=388|issue=10059|pages=2519–31|doi=10.1016/S0140-6736(16)00576-6 |pmid=27140670|s2cid=20948144}}</ref> In later stages, changes to the structure of the lung, such as bronchiectasis, occur.

=== Airway obstruction ===
An airway obstruction can be caused by either an [[intraluminal]] mass such as a [[tumor]] or a [[Foreign body aspiration|foreign body]].<ref name="Kwon 302–307">{{Cite journal|last1=Kwon|first1=K. Y.|last2=Myers|first2=J. L.|last3=Swensen|first3=S. J.|last4=Colby|first4=T. V.|date=March 1995|title=Middle lobe syndrome: a clinicopathological study of 21 patients|journal=Human Pathology|volume=26|issue=3|pages=302–7|doi=10.1016/0046-8177(95)90062-4 |pmid=7890282|doi-access=free}}</ref> The presence of an airway obstruction leads to a cycle of inflammation.<ref name=Mc2013/> It is important to identify the presence of an obstruction because surgical resection is often curative if obstruction is the cause.<ref>{{Cite journal|last1=Priftis|first1=Kostas N.|last2=Mermiri|first2=Despina|last3=Papadopoulou|first3=Athina|last4=Anthracopoulos|first4=Michael B.|last5=Vaos|first5=George|last6=Nicolaidou|first6=Polyxeni|s2cid=5902678|date=October 2005|title=The role of timely intervention in middle lobe syndrome in children|journal=Chest|volume=128|issue=4|pages=2504–10|doi=10.1378/chest.128.4.2504 |pmid=16236916}}</ref> In adults, foreign body aspiration is often associated with an altered state of consciousness. The foreign body is often unchewed food, or part of a tooth or [[Crown (dentistry)|crown]].<ref>{{Cite journal|last1=Rafanan|first1=A. L.|last2=Mehta|first2=A. C.|date=June 2001|title=Adult airway foreign body removal. What's new?|journal=Clinics in Chest Medicine|volume=22|issue=2|pages=319–330|doi=10.1016/s0272-5231(05)70046-0 |pmid=11444115}}</ref> Bronchiectasis that results from foreign body aspiration generally occurs in the right lung in the lower lobe or posterior segments of the upper lobe.<ref name=":6">{{EMedicine|article|296198|Aspiration Pneumonitis and Pneumonia: Overview of Aspiration Pneumonia, Predisposing Conditions for Aspiration Pneumonia, Pathophysiology of Aspiration Pneumonia}}</ref>

=== Lung infections ===
A range of bacterial, mycobacterial, and viral lung infections are associated with the development of bronchiectasis. Bacterial infections commonly associated with bronchiectasis include [[Pseudomonas aeruginosa|''P.&nbsp;aeruginosa'']], [[Haemophilus influenzae|''H.&nbsp;influenzae'']], and [[Streptococcus pneumoniae|''S.&nbsp;pneumoniae'']].<ref name="Mc2013" /> [[Gram-negative bacteria]] are more commonly implicated than [[gram-positive bacteria]].<ref name="Mc2013" /> A history of [[Mycobacterium|mycobacterial]] infections such as [[tuberculosis]] can lead to damage of the airways that predisposes to bacterial colonization.<ref>{{Cite journal|last1=Kwak|first1=Hyun Jung|last2=Moon|first2=Ji-Yong|last3=Choi|first3=Yo Won|last4=Kim|first4=Tae Hyung|last5=Sohn|first5=Jang Won|last6=Yoon|first6=Ho Joo|last7=Shin|first7=Dong Ho|last8=Park|first8=Sung Soo|last9=Kim|first9=Sang-Heon|date=December 2010|title=High prevalence of bronchiectasis in adults: analysis of CT findings in a health screening program|journal=The Tohoku Journal of Experimental Medicine|volume=222|issue=4|pages=237–242|doi=10.1620/tjem.222.237 |pmid=21127394|doi-access=free}}</ref> Severe viral infections in childhood can also lead to bronchiectasis through a similar mechanism.<ref>{{Cite journal|last1=Kim|first1=C. K.|last2=Chung|first2=C. Y.|last3=Kim|first3=J. S.|last4=Kim|first4=W. S.|last5=Park|first5=Y.|last6=Koh|first6=Y. Y.|s2cid=25928060|date=February 2000|title=Late abnormal findings on high-resolution computed tomography after Mycoplasma pneumonia|journal=Pediatrics|volume=105|issue=2|pages=372–8|doi=10.1542/peds.105.2.372 |pmid=10654958}}</ref> [[Nontuberculous mycobacteria]] infections such as [[mycobacterium avium complex|''Mycobacterium avium'' complex]] are found to be a cause in some patients.<ref>{{Cite journal|last1=Dimakou|first1=Katerina|last2=Triantafillidou|first2=Christina|last3=Toumbis|first3=Michail|last4=Tsikritsaki|first4=Kyriaki|last5=Malagari|first5=Katerina|last6=Bakakos|first6=Petros|date=July 2016|title=Non CF-bronchiectasis: Aetiologic approach, clinical, radiological, microbiological and functional profile in 277 patients|journal=Respiratory Medicine|volume=116|pages=1–7|doi=10.1016/j.rmed.2016.05.001 |pmid=27296814|doi-access=free}}</ref> Recent studies have also shown [[Nocardia]] infections to been implicated in bronchiectasis.<ref>{{Cite journal|last1=Woodworth|first1=Michael H.|last2=Saullo|first2=Jennifer L.|last3=Lantos|first3=Paul M.|last4=Cox|first4=Gary M.|last5=Stout|first5=Jason E.|date=March 2017|title=Increasing Nocardia Incidence Associated with Bronchiectasis at a Tertiary Care Center|journal=Annals of the American Thoracic Society|volume=14|issue=3|pages=347–354|doi=10.1513/AnnalsATS.201611-907OC |pmid=28231023|s2cid=11712217}}</ref>

=== Impaired host defenses ===
Impairments in host defenses that lead to bronchiectasis may be congenital, such as with [[primary ciliary dyskinesia]], or acquired, such as with the prolonged use of [[immunosuppressive drug]]s.<ref name=":02">{{Cite journal|last1=Chalmers|first1=James D.|last2=Chang|first2=Anne B.|last3=Chotirmall|first3=Sanjay H.|last4=Dhar|first4=Raja|last5=McShane|first5=Pamela J.|date=15 November 2018|title=Bronchiectasis|journal=Nature Reviews. Disease Primers|volume=4|issue=1|page=45|doi=10.1038/s41572-018-0042-3 |pmid=30442957|s2cid=231984729}}</ref> Additionally, these impairments may be localized to the lungs or systemic throughout the body. In these states of immunodeficiency, there is a weakened or absent [[immune system]] response to severe infections that repeatedly affect the lung and eventually result in bronchial wall injury.<ref>{{Cite journal|last1=Rook|first1=Mieneke|last2=Postma|first2=Dirkje S.|last3=van der Jagt|first3=Eric J.|last4=van Minnen|first4=Cees A.|last5=van der Heide|first5=Jaap J. Homan|last6=Ploeg|first6=Rutger J.|last7=van Son|first7=Willem J.|date=27 January 2006|title=Mycophenolate mofetil and bronchiectasis in kidney transplant patients: a possible relationship|journal=Transplantation|volume=81|issue=2|pages=287–9|doi=10.1097/01.tp.0000188638.28003.96 |pmid=16436974|s2cid=36043580 |doi-access=free}}</ref> [[HIV/AIDS]] is an example of an acquired immunodeficiency that can lead to the development of bronchiectasis.<ref>{{Cite journal|last1=Attia|first1=Engi F.|last2=Miller|first2=Robert F.|last3=Ferrand|first3=Rashida A.|date=February 2017|title=Bronchiectasis and other chronic lung diseases in adolescents living with HIV|journal=Current Opinion in Infectious Diseases|volume=30|issue=1|pages=21–30|doi=10.1097/QCO.0000000000000325 |pmc=5408733|pmid=27753690}}</ref>

=== Aspergillosis ===
[[Allergic bronchopulmonary aspergillosis]] (ABPA) is an inflammatory disease caused by hypersensitivity to the fungus [[Aspergillus fumigatus|''Aspergillus fumigatus'']].<ref>{{Cite journal|last1=Greenberger|first1=Paul A.|last2=Bush|first2=Robert K.|last3=Demain|first3=Jeffrey G.|last4=Luong|first4=Amber|last5=Slavin|first5=Raymond G.|last6=Knutsen|first6=Alan P.|date=November 2014|title=Allergic bronchopulmonary aspergillosis|journal=The Journal of Allergy and Clinical Immunology. In Practice|volume=2|issue=6|pages=703–8|doi=10.1016/j.jaip.2014.08.007 |pmc=4306287|pmid=25439360}}</ref> It is suspected in patients with a long history of asthma and symptoms of bronchiectasis such as a productive, [[Mucopurulent discharge|mucopurulent]] cough.<ref>{{Cite journal|last1=De Soyza|first1=Anthony|last2=Aliberti|first2=Stefano|date=1 January 2017|title=Bronchiectasis and Aspergillus: How are they linked?|journal=Medical Mycology|volume=55|issue=1|pages=69–81|doi=10.1093/mmy/myw109 |pmid=27794529|doi-access=free}}</ref>  Imaging often shows peripheral and central airway bronchiectasis, which is unusual in patients with bronchiectasis caused by other disorders.<ref>{{Cite journal|last1=Agarwal|first1=R.|last2=Chakrabarti|first2=A.|last3=Shah|first3=A.|last4=Gupta|first4=D.|last5=Meis|first5=J. F.|last6=Guleria|first6=R.|last7=Moss|first7=R.|last8=Denning|first8=D. W.|last9=ABPA complicating asthma ISHAM working group|s2cid=24077597|date=August 2013|title=Allergic bronchopulmonary aspergillosis: review of literature and proposal of new diagnostic and classification criteria|journal=Clinical and Experimental Allergy |volume=43|issue=8|pages=850–873|doi=10.1111/cea.12141 |pmid=23889240}}</ref>

=== Autoimmune diseases ===
Several autoimmune diseases have been associated with bronchiectasis. Specifically, individuals with [[rheumatoid arthritis]] and [[Sjögren syndrome]] have increased rates of bronchiectasis.<ref>{{Cite journal|last1=Wilczynska|first1=Maria M.|last2=Condliffe|first2=Alison M.|last3=McKeon|first3=Damian J.|date=April 2013|title=Coexistence of bronchiectasis and rheumatoid arthritis: revisited|journal=Respiratory Care|volume=58|issue=4|pages=694–701|doi=10.4187/respcare.01857 |pmid=22782500|doi-access=free}}</ref><ref>{{Cite journal|last1=Soto-Cardenas|first1=M.-J.|last2=Perez-De-Lis|first2=M.|last3=Bove|first3=A.|last4=Navarro|first4=C.|last5=Brito-Zeron|first5=P.|last6=Diaz-Lagares|first6=C.|last7=Gandia|first7=M.|last8=Akasbi|first8=M.|last9=Siso|first9=A.|last10=Ballester|first10=E.|last11=Torres|first11=A.|date=September 2010|title=Bronchiectasis in primary Sjögren's syndrome: prevalence and clinical significance|journal=Clinical and Experimental Rheumatology|volume=28|issue=5|pages=647–653 |pmid=20883638}}</ref> In these diseases, the symptoms of bronchiectasis usually presents later in the disease course.<ref>{{Cite journal|last1=Chatzidionisyou|first1=Aikaterini|last2=Catrina|first2=Anca I.|date=January 2016|title=The lung in rheumatoid arthritis, cause or consequence?|journal=Current Opinion in Rheumatology|volume=28|issue=1|pages=76–82|doi=10.1097/BOR.0000000000000238 |pmid=26599384|s2cid=24189458}}</ref> Other autoimmune diseases such as [[ulcerative colitis]] and [[Crohn's disease]] also have an association with bronchiectasis.<ref>{{Cite journal|last1=Black|first1=Hugh|last2=Mendoza|first2=Mark|last3=Murin|first3=Susan|date=February 2007|title=Thoracic manifestations of inflammatory bowel disease|journal=Chest|volume=131|issue=2|pages=524–532|doi=10.1378/chest.06-1074 |pmid=17296657}}</ref> Additionally, [[graft-versus-host disease]] in patients who have undergone stem cell transplantation can lead to bronchiectasis as well.<ref name=":02" />

=== Lung injury ===
Bronchiectasis could be caused by: inhalation of [[ammonia]] and other toxic gases,<ref>{{Cite journal|last1=Magis-Escurra|first1=Cecile|last2=Reijers|first2=Monique He|date=25 February 2015|title=Bronchiectasis|journal=BMJ Clinical Evidence|volume=2015 |pmc=4356176|pmid=25715965}}</ref> chronic [[pulmonary aspiration]] of [[Gastric acid|stomach acid]] from [[esophageal reflux]],<ref name="lietal">{{Cite journal|last1=Li|first1=A. M.|last2=Sonnappa|first2=S.|last3=Lex|first3=C.|last4=Wong|first4=E.|last5=Zacharasiewicz|first5=A.|last6=Bush|first6=A.|last7=Jaffe|first7=A.|date=July 2005|title=Non-CF bronchiectasis: does knowing the aetiology lead to changes in management?|journal=The European Respiratory Journal|volume=26|issue=1|pages=8–14|doi=10.1183/09031936.05.00127704 |pmid=15994383|doi-access=free}}</ref> or a [[hiatal hernia]].<ref name="lietal" />

=== Congenital ===
Bronchiectasis may result from congenital disorders that affect [[cilia]] motility or [[ion transport]].<ref name="DAVIDSONS20102">{{cite book|title=Davidson's principles and practice of medicine.|publisher=Churchill Livingstone/Elsevier|others=illustrated by Robert Britton|year=2010|isbn=978-0-7020-3085-7|editor1=Nicki R. Colledge|edition=21st|location=Edinburgh|editor2=Brian R. Walker|editor3=Stuart H. Ralston}}</ref> A common genetic cause is [[cystic fibrosis]], which affects [[chloride]] ion transport.<ref name="auto3" /> Another genetic cause is [[primary ciliary dyskinesia]], a rare disorder that leads to immotility of [[Cilium|cilia]] and can lead to [[situs inversus]].<ref>{{Cite journal|last1=Goutaki|first1=Myrofora|last2=Meier|first2=Anna Bettina|last3=Halbeisen|first3=Florian S.|last4=Lucas|first4=Jane S.|last5=Dell|first5=Sharon D.|last6=Maurer|first6=Elisabeth|last7=Casaulta|first7=Carmen|last8=Jurca|first8=Maja|last9=Spycher|first9=Ben D.|last10=Kuehni|first10=Claudia E.|date=October 2016|title=Clinical manifestations in primary ciliary dyskinesia: systematic review and meta-analysis|journal=The European Respiratory Journal|volume=48|issue=4|pages=1081–95|doi=10.1183/13993003.00736-2016 |pmid=27492829|doi-access=free}}</ref> When situs inversus is accompanied by chronic sinusitis and bronchiectasis, this is known as [[Kartagener's syndrome]].<ref>{{Cite journal|last1=Mishra|first1=Mayank|last2=Kumar|first2=Naresh|last3=Jaiswal|first3=Ashish|last4=Verma|first4=Ajay K.|last5=Kant|first5=Surya|date=October 2012|title=Kartagener's syndrome: A case series|journal=Lung India |volume=29|issue=4|pages=366–9|doi=10.4103/0970-2113.102831 |pmc=3519024|pmid=23243352 |doi-access=free }}</ref> Other rare genetic causes include [[Young's syndrome]]<ref>{{Cite journal|last1=Hendry|first1=W. F.|last2=A'Hern|first2=R. P.|last3=Cole|first3=P. J.|date=18–25 December 1993 |title=Was Young's syndrome caused by exposure to mercury in childhood?|journal=BMJ (Clinical Research Ed.)|volume=307|issue=6919|pages=1579–82|doi=10.1136/bmj.307.6919.1579 |pmc=1697782|pmid=8292944}}</ref> and [[Williams–Campbell syndrome]].<ref name="pmid138448572">{{cite journal|vauthors=WILLIAMS H, CAMPBELL P|date=April 1960|title=Generalized Bronchiectasis associated with Deficiency of Cartilage in the Bronchial Tree|journal=Arch. Dis. Child.|volume=35|issue=180|pages=182–91|doi=10.1136/adc.35.180.182|pmc=2012546|pmid=13844857}}</ref> [[Tracheobronchomegaly]], or Mournier-Kuhn syndrome is a rare condition characterized by significant tracheobronchial dilation and recurrent [[lower respiratory tract infection]]s.<ref>{{Cite journal|last1=Celik|first1=Burcin|last2=Bilgin|first2=Salih|last3=Yuksel|first3=Canan|date=2011|title=Mounier-Kuhn syndrome: a rare cause of bronchial dilation|journal=Texas Heart Institute Journal|volume=38|issue=2|pages=194–6 |pmc=3066798|pmid=21494536}}</ref> Individuals with [[alpha 1-antitrypsin deficiency]] have been found to be particularly susceptible to bronchiectasis, due to the loss of inhibition to enzyme [[elastase]] which cleaves [[elastin]].<ref>{{Cite journal|last1=Parr|first1=David G.|last2=Guest|first2=Peter G.|last3=Reynolds|first3=John H.|last4=Dowson|first4=Lee J.|last5=Stockley|first5=Robert A.|date=15 December 2007|title=Prevalence and impact of bronchiectasis in alpha1-antitrypsin deficiency|journal=American Journal of Respiratory and Critical Care Medicine|volume=176|issue=12|pages=1215–21|doi=10.1164/rccm.200703-489OC |pmid=17872489}}</ref> This decreases the ability of the alveoli to return to normal shape during expiration.<ref>{{cite journal|vauthors=Shin MS, Ho KJ|s2cid=72998738|year=1993|title=Bronchiectasis in patients with alpha 1-antitrypsin deficiency. A rare occurrence?|journal=Chest|volume=104|issue=5|pages=1384–86|doi=10.1378/chest.104.5.1384|pmid=8222792}}</ref>

=== Cigarette smoking ===
A causal role for [[Tobacco smoking|tobacco smoke]] in bronchiectasis has not been demonstrated.<ref name=":02" /> Nonetheless, tobacco smoking can worsen pulmonary function and accelerate the progression of disease that is already present.<ref>{{Cite journal|last1=Martínez-García|first1=Miguel Ángel|last2=Soler-Cataluña|first2=Juan José|last3=Donat Sanz|first3=Yolanda|last4=Catalán Serra|first4=Pablo|last5=Agramunt Lerma|first5=Marcos|last6=Ballestín Vicente|first6=Javier|last7=Perpiñá-Tordera|first7=Miguel|date=November 2011|title=Factors associated with bronchiectasis in patients with COPD|journal=Chest|volume=140|issue=5|pages=1130–7|doi=10.1378/chest.10-1758 |pmid=21546440}}</ref><ref>{{Cite journal|last1=Goeminne|first1=P. C.|last2=Nawrot|first2=T. S.|last3=Ruttens|first3=D.|last4=Seys|first4=S.|last5=Dupont|first5=L. J.|date=February 2014|title=Mortality in non-cystic fibrosis bronchiectasis: a prospective cohort analysis|journal=Respiratory Medicine|volume=108|issue=2|pages=287–296|doi=10.1016/j.rmed.2013.12.015 |pmid=24445062|doi-access=free|hdl=1942/16765|hdl-access=free}}</ref>

==Pathophysiology==
[[File:Bronchiectasis Vicious Cycle Pathogenesis.png|thumb|"Vicious cycle" theory of the pathogenesis of bronchiectasis]]
The development of bronchiectasis requires two factors: an initial injury to the lung (such as from infection, auto-immune destruction of lung tissue, or other destruction of lung tissue (as seen in [[gastroesophageal reflux disease]] or [[aspiration pneumonia|aspiration syndromes]])) which leads to impaired [[mucociliary clearance]], obstruction, or a defect in host defense.<ref name="O'Donnell NEJM" /><ref name="Mc2013" /> This triggers a host immune response from [[neutrophil]]s ([[Neutrophil elastase|elastases]]), [[reactive oxygen species]], and inflammatory [[cytokine]]s that results in progressive destruction of normal lung architecture. In particular, the [[elastic fiber]]s of [[bronchi]] are affected.<ref name="DAVIDSONS2010" /> The result is permanent abnormal dilation and destruction of the major bronchi and bronchiole walls.<ref name="Bronchiectasis">{{cite web |url= https://www.lecturio.com/concepts/bronchiectasis/ | title= Bronchiectasis | website= The Lecturio Medical Concept Library |access-date= 5 July 2021}}</ref>

Disordered neutrophil function is believed to play a role in the pathogenesis of bronchiectasis. [[Neutrophil extracellular traps]] (NETs), which are extracellular fibers secreted by neutrophils that are used to trap and destroy pathogens, are hyperactive in bronchiectasis. Increased NET activity is associated with more severe bronchiectasis.<ref name="O'Donnell NEJM" /> Neutrophil elastase, which is an extracellular protein secreted by neutrophils to destroy pathogens as well as host tissue, is also hyperactive in many cases of bronchiectasis.<ref name="O'Donnell NEJM" /> An increased neutrophil elastase activity is also associated with worse outcomes and more severe disease in bronchiectasis.<ref name="O'Donnell NEJM" /> The initial lung injury in bronchiectasis leads to an impaired mucociliary clearance of the lung airways, which leads to mucous stasis.<ref name="O'Donnell NEJM" /> This mucous stasis leads to bacterial colonization in bronchiectasis, which leads to neutrophil activation.<ref name="O'Donnell NEJM" /> This neutrophil activation leads to further tissue destruction and airway distortion by neutrophils in addition to direct tissue destruction by the pathogenic bacteria.<ref name="O'Donnell NEJM" /> The distorted, damaged lung airways thus have impaired mucociliary clearance, leading to mucous stasis and bacterial colonization, leading to further neutrophil activation and thus fueling a self-perpetuating "vicious cycle" of inflammation in bronchiectasis.<ref name="O'Donnell NEJM" /> This "vicious cycle" theory is the generally accepted explanation for the pathogenesis of bronchiectasis.<ref name=":02"/>

Endobronchial tuberculosis commonly leads to bronchiectasis, either from bronchial [[stenosis]] or secondary traction from fibrosis.<ref name=":6"/> Traction bronchiectasis characteristically affects peripheral bronchi (which lack [[cartilage]] support) in areas of end-stage fibrosis.<ref name=":7">{{EMedicine|article|354167|Bronchiectasis Imaging}}</ref>

== Diagnosis ==
[[File:Bronquiectasia.jpeg|thumb|[[CT scan]] of the lungs showing findings diagnostic of bronchiectasis. White and black arrows point to dilated bronchi characteristic of the disease.]]
The goals of a diagnostic evaluation for bronchiectasis are radiographic confirmation of the diagnosis, identification of potential treatable causes, and functional assessment of the patient. A comprehensive evaluation consists of radiographic imaging, laboratory testing, and [[Pulmonary function testing|lung function testing]].<ref name="Pasteur i1–58">{{Cite journal|last1=Pasteur|first1=M. C.|last2=Bilton|first2=D.|last3=Hill|first3=A. T.|last4=British Thoracic Society Bronchiectasis non-CF Guideline Group|date=July 2010|title=British Thoracic Society guideline for non-CF bronchiectasis|journal=Thorax|volume=65 |issue=Suppl 1|pages=i1–58|doi=10.1136/thx.2010.136119 |pmid=20627931|doi-access=free}}</ref>

Laboratory tests that are commonly part of the initial evaluation include a [[complete blood count]], [[sputum culture]]s for bacteria, [[Mycobacterium|mycobacteria]], and [[Fungus|fungi]], testing for cystic fibrosis, and [[immunoglobulin]] levels.<ref name="auto1"/> Additional tests that are sometimes indicated include testing for specific [[genetic disorder]]s.<ref name="Bronchiectasis"/>

Lung function testing is used for the assessment and monitoring of functional impairment due to bronchiectasis. These tests may include [[spirometry]] and walking tests.<ref name=":02"/> [[Obstructive lung disease|Obstructive lung impairment]] is the most common finding but [[Restrictive lung disease|restrictive lung impairment]] can be seen in advanced disease. Flexible [[bronchoscopy]] may be performed when sputum studies are negative and a focal obstructing lesion is suspected.<ref name="Kwon 302–307"/>

A [[chest X-ray]] is abnormal in most patients with bronchiectasis. [[Computed tomography]] is recommended to confirm the diagnosis and is also used to describe the distribution and grade the severity of the disease. Radiographic findings include airway dilation, bronchial wall thickening, and [[atelectasis]].<ref name="Mc20132">{{cite journal |last1=McShane |first1=PJ |last2=Naureckas |first2=ET |last3=Tino |first3=G |last4=Strek |first4=ME |date=15 September 2013 |title=Non-cystic fibrosis bronchiectasis. |journal=American Journal of Respiratory and Critical Care Medicine |volume=188 |issue=6 |pages=647–56 |doi=10.1164/rccm.201303-0411CI |pmid=23898922}}</ref> Three types of bronchiectasis can be seen on CT scan, namely cylindrical, varicose, and cystic bronchiectasis.<ref>{{Cite journal |last1=Milliron |first1=Bethany |last2=Henry |first2=Travis S. |last3=Veeraraghavan |first3=Srihari |last4=Little |first4=Brent P. |date=July 2015 |title=Bronchiectasis: Mechanisms and Imaging Clues of Associated Common and Uncommon Diseases |url=http://pubs.rsna.org/doi/10.1148/rg.2015140214 |journal=RadioGraphics |language=en |volume=35 |issue=4 |pages=1011–1030 |doi=10.1148/rg.2015140214 |pmid=26024063 |issn=0271-5333|url-access=subscription }}</ref>

<gallery>
File:Bronchiectasis (3705143327).jpg|Bronchiectasis primarily in the [[middle lobe]] of the right lung
File:Bronchiectasis .jpg|Bronchiectasis secondary to a large [[carcinoid]] tumor (not shown) that was completely obstructing the bronchus proximally. Dilation of the airways is present.
</gallery>

==Prevention==
In preventing bronchiectasis, it is necessary to prevent the lung infections and lung damage that can cause it.<ref name=":4" /> Children should be immunized against [[measles]], [[pertussis]], [[pneumonia]], and other acute respiratory infections of childhood. Additionally, parents should stay alert to keep children from inhaling objects such as pieces of food or small toys that may get stuck in the small airways.<ref name=":4" /> [[Smoking]] and other toxic fumes and gases should be avoided by all patients with bronchiectasis to decrease the development of infections (such as [[bronchitis]]) and further complications.<ref>{{cite journal |author=Crofton J |title=Diagnosis and Treatment of Bronchiectasis: I. Diagnosis |journal=Br Med J |volume=1 |issue=5489 |pages=721–3 contd |year=1966 |pmid=5909486 |pmc=1844268 |doi= 10.1136/bmj.1.5489.721}}</ref>

Treatments to slow down the progression of this chronic disease include keeping bronchial airways clear and secretions weakened through various forms of [[Airway clearance technique|airway clearance]]. Aggressively treating bronchial infections with antibiotics to prevent the destructive cycle of infection, damage to bronchi and bronchioles, and further infection is also standard treatment. Regular vaccination against [[pneumonia]], [[influenza]], and [[pertussis]] are generally advised. A healthy [[body mass index]] and regular doctor visits may have beneficial effects on the prevention of progressing bronchiectasis. The presence of [[hypoxemia]], [[hypercapnia]], [[dyspnea]] level and radiographic extent can greatly affect the mortality rate from this disease.<ref>{{cite journal |vauthors=Onen ZP, Eris Gulbay B, Sen E, Akkoca Yildiz O, Saryal S, Acican T, Karabiyikoglu G|title=Analysis of the factors related to mortality in patients with bronchiectasis |journal= Respir. Med. |volume=101 |issue=7 |pages=1390–97 |year=2007 |pmid=17374480|doi=10.1016/j.rmed.2007.02.002 |doi-access=free }}</ref>

==Management==
A comprehensive approach to the management of bronchiectasis is recommended.<ref name="Chalmers 1446–1462">{{Cite journal|last1=Chalmers|first1=James D.|last2=Aliberti|first2=Stefano|last3=Blasi|first3=Francesco|date=May 2015|title=Management of bronchiectasis in adults|journal=The European Respiratory Journal|volume=45|issue=5|pages=1446–62|doi=10.1183/09031936.00119114 |pmid=25792635|doi-access=free}}</ref> It is important to establish whether an underlying modifiable cause, such as immunoglobulin deficiency or [[alpha-1 antitrypsin deficiency]] is present.<ref name="Chalmers 1446–1462"/> The next steps include controlling [[infection]]s and bronchial secretions, relieving airway obstructions, removing affected portions of lung by surgery, and preventing [[Complication (medicine)|complications]].<ref>{{cite journal|last1=José|first1=RJ|last2=Brown|first2=JS|date=October 2014|title=Bronchiectasis |journal=British Journal of Hospital Medicine |volume=75|issue=Suppl 10 |pages=C146-51|doi=10.12968/hmed.2014.75.Sup10.C146|pmid=25289486}}</ref>

=== Airway clearance ===
The goal of [[airway clearance therapy]] is to loosen secretions and interrupt the cycle of inflammation and infection.<ref>{{Cite journal|last1=Flude|first1=Lizzie J.|last2=Agent|first2=Penny|last3=Bilton|first3=Diana|date=June 2012|title=Chest physiotherapy techniques in bronchiectasis|journal=Clinics in Chest Medicine|volume=33|issue=2|pages=351–361|doi=10.1016/j.ccm.2012.02.009 |pmid=22640850}}</ref> [[Airway clearance technique]]s reduce breathing difficulty and coughing, and help people cough up phlegm and [[Mucus|mucus plug]]s.<ref>{{Cite journal|last1=Hill|first1=Adam T.|last2=Barker|first2=Alan F.|last3=Bolser|first3=Donald C.|last4=Davenport|first4=Paul|last5=Ireland|first5=Belinda|last6=Chang|first6=Anne B.|last7=Mazzone|first7=Stuart B.|last8=McGarvey|first8=Lorcan|date=April 2018|title=Treating Cough Due to Non-CF and CF Bronchiectasis With Nonpharmacological Airway Clearance: CHEST Expert Panel Report|journal=Chest|volume=153|issue=4|pages=986–993|doi=10.1016/j.chest.2018.01.014 |pmc=6689075|pmid=29355548}}</ref> Airway clearance usually uses an inhaled agent ([[hypertonic saline]]) with [[chest physiotherapy]], such as [[Chest wall oscillation|high-frequency chest wall oscillation]].<ref name="Mc2013" /> Many airway clearance techniques and devices exist. The choice of a technique or device is based on the frequency and tenacity of phlegm, patient comfort, cost, and the patient's ability to use the technique or device with minimal interference to their lifestyle.<ref name=":2">{{Cite journal|last1=McIlwaine|first1=Maggie|last2=Bradley|first2=Judy|last3=Elborn|first3=J. Stuart|last4=Moran|first4=Fidelma|date=January 2017|title=Personalising airway clearance in chronic lung disease|journal=European Respiratory Review|volume=26|issue=143|page=160086|doi=10.1183/16000617.0086-2016 |pmid=28223396|pmc=9488523 |doi-access=free}}</ref>
The [[Active cycle of breathing|active cycle of breathing technique]] (ACBT), which can be employed with or without a flutter device, is beneficial in treating those with bronchiectasis.<ref>{{cite journal |last1=Athawale |first1=Vrushali |last2=Lalwani |first2=Lajwanti |last3=Mishra |first3=Gyanshankar |title=Comparison of the Active Cycle of Breathing Technique ( ACBT ) versus Active Cycle of Breathing Technique with Flutter in Bronchiectasis |journal=National Journal of Medical Research |date=2020 |volume=10 |issue=4 |pages=178–180 |doi=10.6084/M9.FIGSHARE.13727290 |url=http://njmr.in/home/download/828 |access-date=5 September 2021 |archive-date=5 September 2021 |archive-url=https://web.archive.org/web/20210905062421/http://njmr.in/home/download/828 }}</ref> [[Mucoactive agent|Mucolytic agents]] such as [[dornase alfa]] are not recommended for individuals with non-CF bronchiectasis.<ref name=Mc2013/> [[Mannitol]] is a hyperosmolar agent that is thought to hydrate airway secretions; however, clinical trials with it have not demonstrated efficacy.<ref name=":2" />

=== Anti-inflammatories ===
The two most commonly used classes of [[anti-inflammatory]] therapies are [[macrolide]]s and [[corticosteroid]]s.<ref name=Mc2013/>

Despite also being antibiotics, macrolides exert [[immunomodulator]]y effects on the host inflammatory response without systemic suppression of the immune system.<ref name=Mc2013/> These effects include modifying mucus production, inhibition of [[biofilm]] production, and suppression of [[inflammatory mediator]]s.<ref name=":02"/> Three large multicenter, randomized trials have shown reduced rates of exacerbations and improved cough and dyspnea with use of macrolide therapy.<ref name="auto1">{{Cite journal|last1=Polverino|first1=Eva|last2=Goeminne|first2=Pieter C.|last3=McDonnell|first3=Melissa J.|last4=Aliberti|first4=Stefano|last5=Marshall|first5=Sara E.|last6=Loebinger|first6=Michael R.|last7=Murris|first7=Marlene|last8=Cantón|first8=Rafael|last9=Torres|first9=Antoni|last10=Dimakou|first10=Katerina|last11=De Soyza|first11=Anthony|date=September 2017|title=European Respiratory Society guidelines for the management of adult bronchiectasis|journal=The European Respiratory Journal|volume=50|issue=3|page=1700629|doi=10.1183/13993003.00629-2017 |pmid=28889110|doi-access=free}}</ref> The impact of adverse effects of macrolides such as [[gastrointestinal symptom]]s, [[hepatotoxicity]], and increased [[antimicrobial resistance]] needs ongoing review and study.<ref name=Qi2014/>

[[Inhaled corticosteroid]] therapy can reduce sputum production and decrease airway constriction over a period of time, helping prevent progression of bronchiectasis.<ref name=":3"/> Long-term use of high-dose inhaled corticosteroids can lead to adverse consequences such as [[cataract]]s and [[osteoporosis]].<ref name=Mc2013/> It is not recommended for routine use in children.<ref name="HILL201122">{{cite journal|last=Hill|first=Adam T|author2=Pasteur, Mark|author3=Cornford, Charles|author4=Welham, Sally|author5=Bilton, Diana|date=1 January 2011|title=Primary care summary of the British Thoracic Society Guideline on the management of non-cystic fibrosis bronchiectasis|journal=Primary Care Respiratory Journal|volume=20|issue=2|pages=135–40|doi=10.4104/pcrj.2011.00007|pmc=6549837|pmid=21336465}}</ref> One commonly used therapy is [[beclometasone dipropionate]].<ref>{{cite journal|vauthors=Elborn JS, Johnston B, Allen F, Clarke J, McGarry J, Varghese G|year=1992|title=Inhaled steroids in patients with bronchiectasis|journal=Respir Med|volume=86|issue=2|pages=121–4|doi=10.1016/S0954-6111(06)80227-1|pmid=1615177}}</ref>

=== Antibiotics ===
[[File:Zithromax (Azithromycin) tablets.jpg|thumb|[[Azithromycin]] is a [[macrolide]] commonly used in bronchiectasis.]]

[[Antibiotic]]s are used in bronchiectasis to eradicate [[Pseudomonas aeruginosa|''P.&nbsp;aeruginosa'']] or [[Mrsa|MRSA]], to suppress the burden of chronic bacterial colonization, and to treat exacerbations.<ref name=Mc2013/> The use of daily oral non-macrolide antibiotic treatment has been studied in small case series, but not in randomized trials.<ref name="auto1"/> The role of inhaled antibiotics in non-CF bronchiectasis has recently evolved with two society guidelines and a systematic review suggesting a therapeutic trial of inhaled antibiotics in patients with three or more exacerbations per year and ''P. aeruginosa'' in their sputum.<ref>{{Cite journal|last1=Chang|first1=Anne B.|last2=Bell|first2=Scott C.|last3=Torzillo|first3=Paul J.|last4=King|first4=Paul T.|last5=Maguire|first5=Graeme P.|last6=Byrnes|first6=Catherine A.|last7=Holland|first7=Anne E.|last8=O'Mara|first8=Peter|last9=Grimwood|first9=Keith|last10=extended voting group|date=19 January 2015|title=Chronic suppurative lung disease and bronchiectasis in children and adults in Australia and New Zealand Thoracic Society of Australia and New Zealand guidelines|journal=The Medical Journal of Australia|volume=202|issue=1|pages=21–23|doi=10.5694/mja14.00287 |pmid=25588439|doi-access=free|hdl=10072/132638|hdl-access=free}}</ref><ref>{{Cite journal|last1=Brodt|first1=Alessandra Monteiro|last2=Stovold|first2=Elizabeth|last3=Zhang|first3=Linjie|date=August 2014|title=Inhaled antibiotics for stable non-cystic fibrosis bronchiectasis: a systematic review|journal=The European Respiratory Journal|volume=44|issue=2|pages=382–393|doi=10.1183/09031936.00018414 |pmid=24925920|doi-access=free}}</ref> Options for inhaled antibiotics include aerosolized [[tobramycin]], inhaled [[ciprofloxacin]], aerosolized [[aztreonam]], and aerosolized [[colistin]].<ref name=":02" /> However, there arises a problem with inhaled antibiotic treatments, such as ciprofloxacin, of staying in the desired area of the infected lung tissues for sufficient time to provide optimal treatment.<ref name="ReferenceA">{{Cite journal |last1=Almurshedi |first1=Alanood S. |last2=Aljunaidel |first2=Hessah A. |last3=Alquadeib |first3=Bushra |last4=Aldosari |first4=Basmah N. |last5=Alfagih |first5=Iman M. |last6=Almarshidy |first6=Salma S. |last7=Eltahir |first7=Eram KD |last8=Mohamoud |first8=Amany Z. |date=25 March 2021 |title=Development of Inhalable Nanostructured Lipid Carriers for Ciprofloxacin for Noncystic Fibrosis Bronchiectasis Treatment |journal=International Journal of Nanomedicine |language=English |volume=16 |pages=2405–2417 |doi=10.2147/IJN.S286896 |pmc=8012696 |pmid=33814907 |doi-access=free }}</ref> To combat this and prolong the amount of time the antibiotic spends in the lung tissue, current study trials have moved to develop inhalable nanostructured lipid carriers for the antibiotics.<ref name="ReferenceA"/>

=== Bronchodilators ===
Some clinical trials have shown a benefit with inhaled [[bronchodilator]]s in certain people with bronchiectasis.<ref name=Mc2013/> In people with demonstrated bronchodilator reversibility on [[spirometry]], the use of inhaled bronchodilators resulted in improved dyspnea, cough, and quality of life without any increase in adverse events.<ref name="Pasteur i1–58"/> However, overall, there is a lack of data to recommend the use of bronchodilators in all patients with bronchiectasis.<ref>{{Cite journal|last1=Goyal|first1=Vikas|last2=Chang|first2=Anne B.|date=10 June 2014|title=Combination inhaled corticosteroids and long-acting beta2-agonists for children and adults with bronchiectasis|journal=The Cochrane Database of Systematic Reviews|volume=2017 |issue=6|article-number=CD010327|doi=10.1002/14651858.CD010327.pub2 |pmc=6483496|pmid=24913725}}</ref>

=== Surgery ===
The primary role of [[surgery]] in the management of bronchiectasis is in localized disease to [[Segmental resection|remove segments of the lung]] or to control massive [[hemoptysis]].<ref name=":02" /> Additionally, surgery is used to remove an airway obstruction that is contributing to bronchiectasis. The goals are conservative, aiming to control specific disease manifestations rather than cure or eliminate all areas of bronchiectasis.<ref name=":12">{{Cite journal|last1=Agasthian|first1=T.|last2=Deschamps|first2=C.|last3=Trastek|first3=V. F.|last4=Allen|first4=M. S.|last5=Pairolero|first5=P. C.|date=October 1996|title=Surgical management of bronchiectasis|journal=The Annals of Thoracic Surgery|volume=62|issue=4|pages=976–978; discussion 979–980|doi=10.1016/0003-4975(96)00469-9 |pmid=8823075|doi-access=free}}</ref> Surgical case series have shown low operative mortality rate (less than 2%) and improvement of symptoms in the majority of patients selected to receive surgery.<ref>{{Cite journal|last1=Zhang|first1=Peng|last2=Jiang|first2=Gening|last3=Ding|first3=Jiaan|last4=Zhou|first4=Xiao|last5=Gao|first5=Wen|date=July 2010|title=Surgical treatment of bronchiectasis: a retrospective analysis of 790 patients|journal=The Annals of Thoracic Surgery|volume=90|issue=1|pages=246–250|doi=10.1016/j.athoracsur.2010.03.064 |pmid=20609785}}</ref> However, no randomized clinical trials have been performed evaluating the efficacy of surgery in bronchiectasis.<ref name=":12" />

=== Clinical trials ===
Results from a phase 2 clinical trial were published in 2018.{{r|Brensocatib}} In a placebo-controlled, double-blind study conducted in 256 patients worldwide, patients who received [[brensocatib]] reported prolonged time to the first exacerbation and also reduced rate of yearly exacerbation.{{r|Brensocatib}} Brensocatib (Brinsupri) was approved for medical use in the United States in August 2025.<ref>{{cite press release | title=FDA Approves Brinsupri (brensocatib) as the First and Only Treatment for Non-Cystic Fibrosis Bronchiectasis, a Serious, Chronic Lung Disease | publisher=Insmed | via=PR Newswire | date=12 August 2025 | url=https://www.prnewswire.com/news-releases/fda-approves-brinsupri-brensocatib-as-the-first-and-only-treatment-for-non-cystic-fibrosis-bronchiectasis-a-serious-chronic-lung-disease-302527941.html | access-date=17 August 2025}}</ref>

==Prognosis==
Two clinical scales have been used to predict disease severity and outcomes in bronchiectasis: the Bronchiectasis Severity Index and the FACED scale. The FACED scale uses the [[spirometry|FEV-1]] (forced expiratory volume in 1 second), age of the affected person, presence of chronic infection, extent of disease (number of lung lobes involved) and dyspnea scale rating ([[MRC dyspnea scale]]) to predict clinical outcomes in bronchiectasis. The Bronchiectasis Severity Index uses the same criteria as the FACED scale, in addition to including criteria related to the number of hospital admissions, annual exacerbations, colonization with other organisms, and BMI (body mass index) less than 18.5. A decreased FEV-1, increasing age, presence of chronic infection (especially [[pseudomonas aeruginosa|pseudomonas]]), a greater extent of lung involvement, high clinical dyspnea scale ratings, increased hospital admissions, a high number of annual exacerbations, and a BMI less than 18.5 lead to higher scores on both clinical scales and are associated with a poor prognosis in bronchiectasis; including increased mortality.<ref name="O'Donnell NEJM">{{cite journal |last1=O'Donnell |first1=Anne E. |title=Bronchiectasis — A Clinical Review |journal=New England Journal of Medicine |date=11 August 2022 |volume=387 |issue=6 |pages=533–545 |doi=10.1056/NEJMra2202819|pmid=35947710 |s2cid=251495311 }}</ref>

==Epidemiology==
The prevalence and incidence of bronchiectasis are unclear, as the symptoms are variable.<ref>{{cite encyclopedia | title=Bronchiectasis, Chapter 4, Dean E. Schraufnagel (ed.) | encyclopedia=Breathing in America: Diseases, Progress, and Hope | publisher=American Thoracic Society | date=2010 | url=https://www.thoracic.org/patients/patient-resources/breathing-in-america/ | access-date=30 April 2017 | url-status=live | archive-date=15 April 2017 | archive-url=https://web.archive.org/web/20170415052733/https://www.thoracic.org/patients/patient-resources/breathing-in-america/}}</ref> The disease affects between 1 per 1000 and 1 per 250,000 adults.<ref name=Cot2015/> The disease is more common in women and in the elderly.<ref name=Mc2013/> In a Medicare cohort study in the United States, consisting of adults 65 years and older, the prevalence of bronchiectasis was 701 per 100,000 persons.<ref name="Chest Henkle">{{cite journal |last1=Henkle |first1=Emily |last2=Chan |first2=Benjamin |last3=Curtis |first3=Jeffrey R. |last4=Aksamit |first4=Timothy R. |last5=Daley |first5=Charles L. |last6=Winthrop |first6=Kevin L. |title=Characteristics and Health-care Utilization History of Patients With Bronchiectasis in US Medicare Enrollees With Prescription Drug Plans, 2006 to 2014 |journal=Chest |date=1 December 2018 |volume=154 |issue=6 |pages=1311–1320 |doi=10.1016/j.chest.2018.07.014|pmid=30055168 |s2cid=51864771 }}</ref> A similar prevalence rate of bronchiectasis has been reported in other countries including China, Germany, the United Kingdom, Spain and Singapore.<ref name="O'Donnell NEJM" /> Those with a dual COPD and bronchiectasis diagnosis are more likely to be cigarette smokers and more likely to be hospitalized as compared to those with bronchiectasis without COPD.<ref name="Chest Henkle" /> It became less common since the 1950s, with the introduction of antibiotics.<ref name=Cot2015/> It is more common among certain ethnic groups such as [[indigenous people]].<ref name=Cot2015/>

An estimated 350,000 to 500,000 adults have bronchiectasis in the United States.<ref name=":1">{{Cite journal|last1=Weycker|first1=Derek|last2=Hansen|first2=Gary L.|last3=Seifer|first3=Frederic D.|date=November 2017|title=Prevalence and incidence of noncystic fibrosis bronchiectasis among US adults in 2013|journal=Chronic Respiratory Disease|volume=14|issue=4|pages=377–384|doi=10.1177/1479972317709649 |pmc=5729734|pmid=28555504}}</ref> Specifically, children of the indigenous populations of [[Aboriginal Australians|Australia]], [[Alaska Natives|Alaska]], [[Indigenous peoples in Canada|Canada]] and [[Māori people|New Zealand]] have significantly higher rates than other populations.<ref name=":5">{{Cite journal|last1=Chandrasekaran|first1=Ravishankar|last2=Mac Aogáin|first2=Micheál|last3=Chalmers|first3=James D.|last4=Elborn|first4=Stuart J.|last5=Chotirmall|first5=Sanjay H.|date=22 May 2018|title=Geographic variation in the aetiology, epidemiology and microbiology of bronchiectasis|journal=BMC Pulmonary Medicine|volume=18|issue=1|page=83|doi=10.1186/s12890-018-0638-0 |pmc=5964678|pmid=29788932 |doi-access=free }}</ref> Overall, a shortage of data exists concerning the epidemiology of bronchiectasis in [[Asia]], [[Africa]], and [[South America]].<ref name=":5" />

The prevalence and incidence of bronchiectasis have increased greatly in the 21st century. In a Medicare cohort analysis, consisting of adults 65 years and older in the United States, the annual rates of diagnosis have increased by 8.7% every year between 2000 and 2007.<ref name=Mc2013/><ref name="Seitz Chest">{{cite journal |last1=Seitz |first1=Amy E. |last2=Olivier |first2=Kenneth N. |last3=Adjemian |first3=Jennifer |last4=Holland |first4=Steven M. |last5=Prevots |first5=D. Rebecca |title=Trends in Bronchiectasis Among Medicare Beneficiaries in the United States, 2000 to 2007 |journal=Chest |date=1 August 2012 |volume=142 |issue=2 |pages=432–439 |doi=10.1378/chest.11-2209 |pmid=22302301 |pmc=3425339 |language=English |issn=0012-3692}}</ref> This large increase in the diagnosis of bronchiectasis may be due to increased recognition of the disease (including more widespread use of [[CT scan]]s) or it may be due to an increase in the underlying causes of bronchiectasis.<ref name="O'Donnell NEJM" />

==History==
[[René Laennec]], the man who invented the [[stethoscope]], used his invention to first discover bronchiectasis in 1819.<ref>{{cite journal |author=Roguin, A |title=Rene Theophile Hyacinthe Laënnec (1781–1826): The Man Behind the Stethoscope |journal=Clin Med Res|volume=4 |issue=3 |pages=230–35 |year=2006 |doi=10.3121/cmr.4.3.230 |pmc=1570491 |pmid=17048358}}</ref>

The disease was researched in greater detail by Sir [[William Osler]], one of the four founding professors of [[Johns Hopkins Hospital]], in the late 1800s. It is suspected that Osler himself died of complications from undiagnosed bronchiectasis. His biographies mention that he had frequent, severe chest infections for many years.<ref>{{cite journal |author=Wrong O |title=Osler and my father |journal=J R Soc Med |volume=96 |issue=6 |pages=462–64 |year=2003 |pmid= 12949207|doi=10.1177/014107680309600914 |pmc=539606}}</ref>

The term "bronchiectasis" comes from the Greek words ''bronkhia'' (meaning "airway") and ''ektasis (''meaning "widening").<ref>{{Cite web|url=https://www.lexico.com/en/definition/bronchiectasis|archive-url=https://web.archive.org/web/20191109175656/https://www.lexico.com/en/definition/bronchiectasis|archive-date=9 November 2019|title=Bronchiectasis {{!}} Definition of Bronchiectasis by Lexico|website=Lexico Dictionaries {{!}} English|access-date=21 November 2019}}</ref>

==Society and culture==

[[Judith Durham]] of the [[Australia]]n band [[The Seekers]] died of bronchiectasis on 5 August 2022, at the age of 79.<ref>{{Cite web |last=Graham |first=Jackson |date=6 August 2022 |title=Judith Durham, lead singer of The Seekers, dies aged 79 |url=https://www.watoday.com.au/culture/music/judith-durham-lead-singer-of-the-seekers-dies-aged-79-20220806-p5b7t1.html |access-date=10 August 2023 |website=WAtoday |language=en}}</ref>

==References==
{{Reflist|refs=
<ref name=Brensocatib>{{cite journal|vauthors=Chalmers JD, Haworth CS, Metersky ML, Loebinger MR, Blasi F, Sibila O, O'Donnell AE, Sullivan EJ, Mange KC, Fernandez C, Zou J, Daley CL, ((WILLOW Investigators))|title=Phase 2 Trial of the DPP-1 inhibitor Brensocatib in Bronchiectasis|date=September 2020|journal=The New England Journal of Medicine|volume=383|issue=22|pages=2127–37|doi=10.1056/NEJMoa2021713|pmid=32897034|s2cid=221540296|doi-access=free}}</ref>
}}

==External links==
{{Commons category|Bronchiectasis}}
{{EB1911 poster|Bronchiectasis}}
{{Medical condition classification and resources|
  ICD9           = {{ICD9|494}}, {{ICD9|748.61}} |
  ICD10           = {{ICD10|J|47||j|40}}, {{ICD10|Q|33|4|q|30}}|
  OMIM           = |
  OMIM_mult      = |
  MedlinePlus    = 000144 |
  eMedicineSubj  = article |
  eMedicineTopic = 296961 |
  DiseasesDB     = 1684 |
  MeshID         = D001987 |
}}
{{Respiratory pathology}}
{{Congenital malformations and deformations of respiratory system}}
{{Radiologic signs}}
{{Portal bar | Medicine}}
{{Authority control}}

[[Category:Chronic lower respiratory diseases]]
[[Category:Congenital disorders of respiratory system]]
[[Category:Wikipedia medicine articles ready to translate]]
[[Category:Wikipedia emergency medicine articles ready to translate]]