View source for Histoplasmosis

{{short description|Fungal infection of the lungs}}
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{{Infobox medical condition (new)
| name            = Histoplasmosis
| synonyms        = '''Cave disease''',<ref name="Bolognia" /> '''Darling's disease''',<ref name="Bolognia" /> '''Ohio valley disease''',<ref name="Bolognia" /> '''Reticuloendotheliosis''',<ref name="Bolognia">{{cite book | last1 = Rapini | first1 = Ronald P. | last2 = Bolognia | first2 = Jean L. | last3 = Jorizzo | first3 = Joseph L. |title=Dermatology: 2-Volume Set |publisher=Mosby |location=St. Louis |year=2007 |isbn=978-1-4160-2999-1 }}</ref> '''[[Spelunk]]er's lung''' and '''Caver's disease'''
| image           = Histoplasmosis capsulatum.jpg
| caption         = ''[[Histoplasma capsulatum]]''. Methenamine [[silver stain]] showing histopathologic changes in histoplasmosis
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| field           = [[Infectious disease (medical specialty)|Infectious disease]]
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'''Histoplasmosis''' is a [[fungal infection]] caused by ''[[Histoplasma capsulatum]]''.<ref name="John2017Hist">{{cite book|last=Johnstone |first=Ronald B.|title=Weedon's Skin Pathology Essentials |url=https://books.google.com/books?id=NTE_DAAAQBAJ|year=2017|publisher=Elsevier |edition=2nd|isbn=978-0-7020-6830-0|page=452|chapter=25. Mycoses and Algal infections}}</ref><ref>{{cite journal | vauthors = Stenn F | title = Cave disease or speleonosis | journal = Archives of Internal Medicine | volume = 105 | issue = 2 | pages = 181–3 | date = February 1960 | pmid = 13834312 | doi = 10.1001/archinte.1960.00270140003001 }}</ref> Symptoms of this infection vary greatly, but the disease affects primarily the [[lung]]s.<ref name=Sherris>{{cite book |veditors = Ryan KJ, Ray CG | title = Sherris Medical Microbiology |url = https://archive.org/details/sherrismedicalmi00ryan |url-access = limited | edition = 4th | pages=[https://archive.org/details/sherrismedicalmi00ryan/page/n691 674]–6 | publisher = McGraw Hill | year = 2004 | isbn = 978-0-8385-8529-0 }}</ref> Occasionally, other organs are affected; called disseminated histoplasmosis, it can be fatal if left untreated.

''H. capsulatum'' is found in soil, often associated with decaying bat [[guano]] or bird droppings. Humans may inhale infectious spores after disrupting the soil via excavation or construction. ''H.&nbsp;capsulatum'' has a one to two week [[incubation period]] within human lungs before symptoms arise.<ref>{{Cite book |last=Pendergast |first=Mark |title=Inside the Outbreaks: The Elite Medical Detectives of the Epidemic Intelligence Service |date=2010 |publisher=[[Houghton Mifflin Harcourt]] |isbn=978-0-15-101120-9 |pages=13–14}}</ref> The disease is common among [[AIDS]] patients due to their [[immunosuppression]].<ref name=Robbins>{{cite book |vauthors=Cotran RS, Kumar V, Fausto N, Robbins SL, Abbas AK |title=Robbins and Cotran Pathologic Basis of Disease |publisher=Elsevier/Saunders |location=St. Louis |year=2005 |pages=754–5 |isbn=978-0-7216-0187-8 }}</ref>

From 1938 to 2013 in the US, 105 outbreaks were reported in a total of 26 states and Puerto Rico. In 1978 to 1979 during a large urban outbreak in which 100,000 people were exposed to the fungus in [[Indianapolis]],<ref>{{cite web|url=https://www.in.gov/health/erc/infectious-disease-epidemiology/histoplasmosis-a-hoosier-concern/|title=Histoplasmosis: A Hoosier Concern|first=Epidemiology Resource|last=Center|date=April 12, 2021|website=Epidemiology Resource Center}}</ref> victims had [[pericarditis]], rheumatological syndromes, esophageal and vocal cord ulcers, [[parotitis]], [[adrenal insufficiency]], [[uveitis]], [[fibrosing mediastinitis]], [[interstitial nephritis]], intestinal [[lymphangiectasia]], and [[epididymitis]]. Histoplasmosis mimics [[Common cold|colds]], [[pneumonia]], and the [[Influenza|flu]], and can be shed by bats in [[guano|their feces]].

==Signs and symptoms==
[[Image:Histoplasmosis, due to the fungus Histoplasma capsulatum skin lesion 6840 lores.jpg|thumb|Skin lesion on the upper lip due to ''H.&nbsp;capsulatum'' infection]]
If symptoms of histoplasmosis infection occur, they start within 3 to 17 days after exposure; the typical time is 12–14 days. Most affected individuals have clinically silent manifestations and show no apparent ill effects. The [[Acute (medical)|acute]] phase of histoplasmosis is characterized by nonspecific respiratory symptoms, often cough or flu-like. [[Chest X-ray]] findings are normal in 40–70% of cases.<ref name=Silberberg_2007>{{cite web | title=Radiology Teaching Files: Case 224856 (Histoplasmosis) | author=Silberberg P | url=http://www.mypacs.net/cases/HISTOPLASMOSIS-224856.html | date=2007-03-26 | access-date=2007-07-27 | archive-url=https://web.archive.org/web/20160303195419/http://www.mypacs.net/cases/HISTOPLASMOSIS-224856.html | archive-date=2016-03-03 }}</ref> Chronic histoplasmosis cases can  resemble [[tuberculosis]];<ref name=Tong1983>{{cite journal | vauthors = Tong P, Tan WC, Pang M | title = Sporadic disseminated histoplasmosis simulating miliary tuberculosis | journal = British Medical Journal | volume = 287 | issue = 6395 | pages = 822–3 | date = September 1983 | pmid = 6412842 | pmc = 1549119 | doi = 10.1136/bmj.287.6395.822 }}</ref><ref name=Gari-Toussaint1987>{{cite journal | vauthors=Gari-Toussaint, Marty P, Le Fichoux Y, Loubière R | title=Histoplasmose d'importation à ''Histoplasma capsulatum'', données biocliniques et thérapeutiques variées, à propos de trois cas observés dans les Alpes maritimes | journal=Bull Soc Fr Mycol Med | volume=16| issue=1| pages=87–90| year=1987| url=https://www.scribd.com/full/6931699?access_key=key-1q4cq6j8cywaani3s539}}</ref> disseminated histoplasmosis affects multiple organ systems and is fatal unless treated.<ref name=Kauffman>{{cite journal | vauthors = Kauffman CA | title = Histoplasmosis: a clinical and laboratory update | journal = Clinical Microbiology Reviews | volume = 20 | issue = 1 | pages = 115–32 | date = January 2007 | pmid = 17223625 | pmc = 1797635 | doi = 10.1128/CMR.00027-06 }}</ref>

While histoplasmosis is the most common cause of [[mediastinitis]], this remains a relatively rare disease. Severe infections can cause [[hepatosplenomegaly]], [[lymphadenopathy]], and adrenal enlargement.<ref name=Sherris/> Lesions often leave calcification nodules as they are healed.<ref>{{cite journal |title=Disseminated histoplasmosis from a calcified lung nodule after long-term corticosteroid therapy in an elderly Japanese patient: A case report |journal=[[Medicine (Baltimore)]] |last1=Keigo |first1=Kobayashi |first2=Asakura |last2=Takanori |doi=10.1097/MD.0000000000015264 |year=2019 |issue=17 |first3=Kawada |last3=Ichiro |first4=Hasegawa |last4=Hanako |first5=Chubachi |last5=Shotaro| first6=Ohara |last6=Kentaro |first7=Kuramoto |last7=Junko |first8=Sugiura |last8=Hiroaki |first9=Fujishima |last9=Seitaro |volume=98 |article-number=e15264 |issn=1536-5964 |pmc=6831385 |pmid=31027078}}</ref>

[[Presumed ocular histoplasmosis syndrome]] <!-- (POHS) --> causes [[chorioretinitis]], where the [[choroid]] and [[retina]] of the eyes are scarred, resulting in a loss of vision not unlike [[macular degeneration]]. Despite its name, the relationship to ''Histoplasma'' is controversial.<ref>{{cite journal | vauthors = Thuruthumaly C, Yee DC, Rao PK | s2cid = 43761401 | title = Presumed ocular histoplasmosis | journal = Current Opinion in Ophthalmology | volume = 25 | issue = 6 | pages = 508–12 | date = November 2014 | pmid = 25237930 | doi = 10.1097/ICU.0000000000000100 }}</ref><ref>{{cite journal | vauthors = Nielsen JS, Fick TA, Saggau DD, Barnes CH | s2cid = 25507234 | title = Intravitreal anti-vascular endothelial growth factor therapy for choroidal neovascularization secondary to ocular histoplasmosis syndrome | journal = Retina | volume = 32 | issue = 3 | pages = 468–72 | date = March 2012 | pmid = 21817958 | doi = 10.1097/IAE.0b013e318229b220 }}</ref> Distinct from POHS, acute ocular histoplasmosis may rarely occur in immunodeficiency.<ref>{{cite journal | vauthors = Macher A, Rodrigues MM, Kaplan W, Pistole MC, McKittrick A, Lawrinson WE, Reichert CM | title = Disseminated bilateral chorioretinitis due to Histoplasma capsulatum in a patient with the acquired immunodeficiency syndrome | journal = Ophthalmology | volume = 92 | issue = 8 | pages = 1159–64 | date = August 1985 | pmid = 2413418 | doi = 10.1016/s0161-6420(85)33921-0 }}</ref><ref>{{cite journal | vauthors = Gonzales CA, Scott IU, Chaudhry NA, Luu KM, Miller D, Murray TG, Davis JL | title = Endogenous endophthalmitis caused by Histoplasma capsulatum var. capsulatum: a case report and literature review | journal = Ophthalmology | volume = 107 | issue = 4 | pages = 725–9 | date = April 2000 | pmid = 10768335 | doi = 10.1016/s0161-6420(99)00179-7 }}</ref>

===Complications===
In the absence of proper treatment, and especially in [[immunocompromised]] individuals, complications can arise. These include recurrent pneumonia, [[respiratory failure]], fibrosing mediastinitis, [[superior vena cava syndrome]], pulmonary vessel obstruction, and progressive fibrosis of lymph nodes. Fibrosing mediastinitis is a serious complication and can be fatal. [[health effects of smoking|People who smoke]] and people with structural [[lung disease]] have a higher probability of developing chronic cavitary histoplasmosis.{{citation needed|date=January 2018}}

After healing of lesions, hard, calcified lymph nodes can erode the walls of the airway, causing [[hemoptysis]].<ref>{{cite web |url=https://www.lecturio.com/concepts/hemoptysis/| title=Hemoptysis|website=The Lecturio Medical Concept Library |access-date= 24 July 2021}}</ref>

==Mechanisms==
''H. capsulatum'' grows in soil and material contaminated with bird or bat droppings ([[guano]]). The fungus has been found in poultry-house litter, caves, areas harboring bats, and bird roosts (particularly those of [[starling]]s). The fungus is [[Thermally dimorphic fungus|thermally dimorphic]]; in the environment, it grows as a brownish [[mycelium]], and at body temperature (37&nbsp;°C in humans), it morphs into a [[yeast]]. Histoplasmosis is not contagious but is contracted by inhalation of the spores from disturbed soil or guano.<ref name=Sherris/> The inoculum is represented principally by [[microconidia]]. These are inhaled and reach the alveoli. In the alveoli, macrophages ingest these microconidia. They survive inside the [[phagosome]]. As the fungus is thermally dimorphic, these microconidia are transformed into yeast. They grow and multiply inside the phagosome. The macrophages travel in the lymphatic circulation and can spread the disease to different organs.<ref>{{cite web |url=https://www.lecturio.com/concepts/histoplasma-histoplasmosis/| title=Histoplasma/Histoplasmosis
|website=The Lecturio Medical Concept Library |access-date= 24 July 2021}}</ref>

Within the phagosome, the fungus has an absolute requirement for [[thiamine]].<ref>Garfoot AL, Zemska O, Rappleye CA (2013) ''Histoplasma capsulatum'' depends on ''de novo'' vitamin biosynthesis for intraphagosomal proliferation. Infect Immum</ref> Cell-mediated immunity for histoplasmosis develops within 2 weeks. If the patient has strong cellular immunity, macrophages, epithelial cells, and lymphocytes surround the organisms and contain them, and eventually calcify. In immunocompromised individuals, the organisms disseminate to different organs such as bone, spleen, liver, adrenal glands, and mucocutaneous membranes, resulting in [[progressive disseminated histoplasmosis]]. Chronic lung disease can manifest.<ref>{{cite web |url=https://www.mayoclinic.org/diseases-conditions/histoplasmosis/symptoms-causes/syc-20373495| title=Histoplasmosis|website=Mayo Clinic |access-date= 24 July 2021}}</ref>

==Diagnosis==
[[Image:Chest X-ray acute pulmonary histoplasmosis PHIL 3954.jpg|thumb|[[Chest X-ray]] of a patient with acute pulmonary histoplasmosis]]
Clinically,  a wide spectrum of disease manifestations occurs, making diagnosis somewhat difficult. More severe forms include the chronic pulmonary form, often occurring in the presence of underlying pulmonary disease, and a disseminated form, which is characterized by the progressive spread of infection to extrapulmonary sites. Oral manifestations have been reported as the main complaint of the disseminated forms, leading the patient to seek treatment, whereas pulmonary symptoms in disseminated disease may be mild or even misinterpreted as flu.<ref>Brazão-Silva MT, Mancusi GW, Bazzoun FV, Ishisaaki GY, Marcucci M. A gingival manifestation of histoplasmosis leading diagnosis. Contemp Clin Dent. V.4 (1). 2013 (http://www.contempclindent.org/text.asp?2013/4/1/97/111621)</ref> Histoplasmosis can be diagnosed by samples containing the fungus taken from sputum (via [[bronchoalveolar lavage]]), blood, or infected organs.  It can also be diagnosed by detection of [[antigens]] in blood or urine samples by [[ELISA]] or [[polymerase chain reaction]]. Antigens can [[Cross-reactivity|cross-react]] with antigens of [[African histoplasmosis]] (caused by ''[[Histoplasma duboisii]]''), [[blastomycosis]], [[coccidioidomycosis]], [[paracoccidioidomycosis]], and [[talaromycosis]] infection. Histoplasmosis can also be diagnosed by a test for [[antibodies]] against ''Histoplasma'' in the blood.  ''Histoplasma'' skin tests indicate whether someone has been exposed, but do not indicate whether they have the disease.<ref name=Sherris/> Formal histoplasmosis diagnoses are often confirmed only by culturing the fungus directly.<ref name=Robbins/> [[Sabouraud agar]] is an agar growth medium on which the fungus can be cultured. Cutaneous manifestations of disseminated disease are diverse and often present as a nondescript rash with systemic complaints. Diagnosis is best established by urine antigen testing, as blood cultures may take up to 6 weeks for diagnostic growth to occur and serum antigen testing often comes back with a false negative before 4 weeks of disseminated infection.<ref>{{cite journal | vauthors = Rosenberg JD, Scheinfeld NS | title = Cutaneous histoplasmosis in patients with acquired immunodeficiency syndrome | journal = Cutis | volume = 72 | issue = 6 | pages = 439–45 | date = December 2003 | pmid = 14700213 }}</ref>

=== Types ===
Histoplasmosis may be divided into these types:<ref name="Andrews">{{cite book |last1 = James | first1 = William D. | last2 = Berger | first2 = Timothy G. |title=Andrews' Diseases of the Skin: clinical Dermatology |publisher=Saunders Elsevier |year=2006 |isbn=978-0-7216-2921-6 |display-authors=etal}}</ref>{{rp|316–317}}

:* [[Primary pulmonary histoplasmosis]]
:* [[Progressive disseminated histoplasmosis]]
:* [[Primary cutaneous histoplasmosis]]
:* [[African histoplasmosis]]

<gallery>
File:Histopathology of histoplasma, HE stain.png|Histopathology of ''Histoplasma capsulatum'', [[H&E stain]], showing organisms surrounded by halos, in a [[granuloma]] of epithelioid [[histiocytes]]
File:Histopathology of Histoplasma capsulatum, GMS stain.jpg|Histopathology of ''Histoplasma capsulatum'', [[GMS stain]], showing narrow budding yeast
Image:Histoplasma capsulatum var. duboisii. PHIL 4221 lores.jpg|''Histoplasma capsulatum'' var. ''duboisii'', methenamine silver stain
Image:Tuberculate macroconida of the Jamaican isolate of Histoplasma capsulatum PHIL 4023 lores.jpg|Macroconidia form of ''Histoplasma capsulatum''
</gallery>

==Prevention==
Testing or decontaminating most sites possibly contaminated with ''H.&nbsp;capsulatum'' is impractical, but the sources below list environments where histoplasmosis is common, and precautions to reduce a person's risk of exposure, in the three parts of the world where the disease is prevalent. Precautions common to all geographical locations would be to avoid accumulations of bird or bat droppings.{{citation needed|date=July 2020}}

The US National Institute for Occupational Safety and Health <!-- (NIOSH) --> provides information on work practices and personal protective equipment that may reduce the risk of infection.<ref>{{cite report |via=NIOSH Publications and Products |title=Histoplasmosis - Protecting Workers at Risk |id=DHHS (NIOSH) Publication Number 2005-109 |url=https://www.cdc.gov/niosh/docs/2005-109/|publisher=Centers for Disease Control and Prevention|access-date=13 August 2017|date=December 2004 |doi=10.26616/NIOSHPUB2005109|url-access=subscription}}</ref>

A review paper includes information on locations in which ''Histoplasma'' has been found in Africa (in chicken runs, on bats, in the caves bats inhabit, and in soil), and a thorough reference list including English, French, and Spanish language references.<ref>{{cite journal |vauthors=Gugnani HC, Muotoe-Okafor F |title=African Histoplasmosis: a review |journal=Revista Iberoamericana de Micologia |volume=14 |issue=4 |pages=155–159 |date=December 1997 |pmid=15538817 |url=http://www.reviberoammicol.com/1997-14/155159.pdf}}{{open access}}</ref>

==Treatment==
In the majority of [[Immunocompetence|immunocompetent]] individuals, histoplasmosis resolves without any treatment. [[Antifungal medication]]s are used to treat severe cases of acute histoplasmosis and all cases of chronic and disseminated disease. Typical treatment of severe disease first involves treatment with [[amphotericin B]], followed by oral [[itraconazole]].<ref>{{cite journal | vauthors = Wheat LJ, Freifeld AG, Kleiman MB, Baddley JW, McKinsey DS, Loyd JE, Kauffman CA | title = Clinical practice guidelines for the management of patients with histoplasmosis: 2007 update by the Infectious Diseases Society of America | journal = Clinical Infectious Diseases | volume = 45 | issue = 7 | pages = 807–25 | date = October 2007 | pmid = 17806045 | doi = 10.1086/521259 | doi-access =  | s2cid = 7182568 }}</ref><ref>{{MerckHome|17|197|g||Histoplasmosis: Fungal Infections}}</ref>

Liposomal preparations of amphotericin B are more effective than deoxycholate preparations. The liposomal preparation is preferred in patients who might be at risk of nephrotoxicity, although all preparations of amphotericin B have a risk of nephrotoxicity. Individuals on amphotericin B are monitored for impaired kidney function.<ref>{{cite journal | vauthors = Moen MD, Lyseng-Williamson KA, Scott LJ | s2cid = 34340503 | title = Liposomal amphotericin B: a review of its use as empirical therapy in febrile neutropenia and in the treatment of invasive fungal infections | journal = Drugs | volume = 69 | issue = 3 | pages = 361–92 | year = 2009 | pmid = 19275278 | doi = 10.2165/00003495-200969030-00010 }}</ref> Liposomal amphotericin B is better at treating people with progressive disseminated Histoplasmosis and underlying HIV when compared to deoxycholate amphotericin B. Meanwhile, fluconazole performs poorly when compared to other azoles.<ref>{{cite journal | vauthors = Murray M, Hine P | title = Treating progressive disseminated Histoplasmosis in people living with HIV | journal = The Cochrane Database of Systematic Reviews | volume = 4 | article-number = CD013594 | date = April 2020 | issue = 4 | pmid = 32343003 | pmc = 7192368 | doi = 10.1002/14651858.CD013594 | collaboration = Cochrane Infectious Diseases Group }}</ref>

Treatment with itraconazole must continue for at least a year in severe cases,<ref>{{cite journal|vauthors=Barron MA, Madinger NE|title=Opportunistic Fungal Infections, Part 3: Cryptococcosis, Histoplasmosis, Coccidioidomycosis, and Emerging Mould Infections|journal=Infections in Medicine|date=November 18, 2008|url=http://www.consultantlive.com/infection/article/1145625/1404367|access-date=July 15, 2009|archive-date=March 14, 2010|archive-url=https://web.archive.org/web/20100314111604/http://www.consultantlive.com/infection/article/1145625/1404367}}</ref> while in acute pulmonary Histoplasmosis, 6 to 12 weeks treatment is sufficient. Alternatives to itraconazole are [[posaconazole]], [[voriconazole]], and [[fluconazole]]. Individuals taking itraconazole are monitored for hepatic function.{{citation needed|date=January 2023}}

== Prognosis ==
About 90% of patients with normal immune systems regain health without any intervention. Less than 5% need serious treatments.{{citation needed|date=July 2020}}

==Epidemiology==
''H. capsulatum'' is found throughout the world. It is [[Endemic (epidemiology)|endemic]] in certain areas of the United States, particularly in states bordering the [[Ohio River]] valley and the lower [[Mississippi River]]. The humidity and acidity patterns of soil are associated with endemicity. Bird and bat droppings in soil promote the growth of ''Histoplasma''. Contact with such soil aerosolizes the microconidia, which can infect humans. It is also common in caves in [[Southern Africa|Southern]] and [[East Africa]]. Positive histoplasmin skin tests occur in as many as 90% of the people living in areas where ''H.&nbsp;capsulatum'' is common, such as the eastern and central United States.<ref name=Sherris/>

In Canada, the [[St. Lawrence River Valley]] is the site of the most frequent infections, with 20–30% of the population testing positive.<ref>{{cite web |url= http://www.ccohs.ca/oshanswers/diseases/histopla.html|title=Histoplasmosis|author=<!--Staff writer(s); no by-line.--> |date= July 1, 2013 |website=www.ccohs.ca|publisher=Canadian Centre for Occupational Health & Safety}}</ref> A review of reported cases in 2018 showed disease presence throughout [[Southeast Asia]],<ref>{{cite journal | vauthors = Baker J, Setianingrum F, Wahyuningsih R, Denning DW | title = Mapping Histoplasmosis in South East Asia - implications for diagnosis in AIDS | journal = Emerging Microbes & Infections | volume = 8 | issue = 1 | pages = 1139–1145 | date = Jan 2019 | pmid = 31364950 | doi = 10.1080/22221751.2019.1644539 | pmc = 6711083 | doi-access = free }}</ref> In India, the [[Ganges|Gangetic]] West [[West Bengal|Bengal]] is the site of most frequent infections, with 9.4% of the population testing positive.<ref>{{cite journal | vauthors = Sanyal M, Thammayya A | title = Histoplasma capsulatum in the soil of Gangetic Plain in India | journal = The Indian Journal of Medical Research | volume = 63 | issue = 7 | pages = 1020–8 | date = July 1975 | pmid = 1213788 }}</ref> ''H.&nbsp;c. capsulatum'' was isolated from the local soil proving endemicity of histoplasmosis in West Bengal.<ref>{{cite journal | vauthors = Sanyal M, Thammayya A | title = Skin Sensitivity To Histoplasmin in Calcutta and Its Neighbourhood | journal = Indian Journal of Dermatology, Venereology and Leprology | volume = 46 | issue = 2 | pages = 94–98 | year = 1980 | pmid = 28218139 }}</ref><!--? add Brazil PMID 23503487  PMID 366428 PMID 20445761 and several others; also, more on Africa PMID 15597674; also, French returning from Cuba, and Martinique tourists; also ? add ddx in cancer PMID 24043490 PMID 24043490 PMID 24728897; also construction sites PMID 15983912; also ? prison and courthouses; also Asia-->

In non-endemic countries, 40–50% of histoplasmosis cases are diagnosed in immunocompromised patients (HIV/AIDS, transplanted patients, cancer patients).<ref>{{cite journal |last1=Zerbato |first1=Verena |last2=Di Bella |first2=Stefano |last3=Pol |first3=Riccardo |last4=D'Aleo |first4=Francesco |last5=Angheben |first5=Andrea |last6=Farina |first6=Claudio |last7=Conte |first7=Marco |last8=Luzzaro |first8=Francesco |last9=Lombardi |first9=Gianluigi  |last10=Luzzati |first10=Roberto |last11=Principe |first11=Luigi |date=2023 |title=Endemic Systemic Mycoses in Italy: A Systematic Review of Literature and a Practical Update |journal=Mycopathologia |language=en |volume=188 |issue=4 |pages=307–334 |doi=10.1007/s11046-023-00735-z |issn=0301-486X |pmc=10386973 |pmid=37294504}}</ref>

== Histoplasmosis in workplaces ==
''H. capsulatum'' is commonly found across the United States. The fungus can grow in any material contaminated with bird and bat droppings, but particularly manifests in soils.<ref name=":0">{{cite web |title=Histoplasmosis |url=https://medlineplus.gov/histoplasmosis.html |access-date=2023-12-04 |website=medlineplus.gov}}</ref> Histoplasma can present itself as an occupational hazard through the causation of the infection Histoplasmosis. Workers in various fields can be exposed to the fungus as spores can be released into the air through any activities that disturb the soil.<ref name=":1">{{cite web |date=2022-08-17 |title=Histoplasmosis in the Workplace {{!}} NIOSH {{!}} CDC |url=https://www.cdc.gov/niosh/newsroom/feature/histoplasmosis.html |access-date=2023-12-04 |website=www.cdc.gov |language=en-us}}</ref>  Due to this, occupations at a higher risk for exposure include construction and demolition, [[landscaping]], [[mining]], [[quarrying]], [[oil and gas extraction]], [[agriculture]] and [[forestry]] industries.<ref name=":1" /> Common symptoms in workers are similar to those of the exposed general public, such as nonspecific respiratory symptoms like a cough. However, workplace exposures tend to lead to larger outbreaks than non-occupational histoplasmosis,<ref name=":0" /> and scientific reviews have shown that occupational histoplasmosis accounts for approximately one third of all documented outbreaks.<ref>{{cite journal |last1=de Perio |first1=Marie |last2=Benedict |first2=Kaitlin |last3=Williams |first3=Samantha |last4=Niemeier-Walsh |first4=Christine |last5=Green |first5=Brett J. |last6=Coffey |first6=Christopher |last7=Di Giuseppe |first7=Michelangelo |last8=Toda |first8=Mitsuru |last9=Park |first9=Ju-Hyeong |date=26 June 2021 |title=Occupational Histoplasmosis: Epidemiology and Prevention Measures |journal=Journal of Fungi |volume=7 |issue=7 |page=510 |doi=10.3390/jof7070510 |pmid=34206791 |pmc=8306883 |doi-access=free }}</ref> Though the disease is usually not severe, there have been instances of outbreaks among workers leading to death.<ref>{{cite web |last1=Armstrong |first1=Paige A |last2=Beard |first2=John D |last3=Bonilla |first3=Luis |date=2 December 2018 |title=Outbreak of Severe Histoplasmosis Among Tunnel Workers |url=https://academic.oup.com/cid/article/66/10/1550/4683412 |access-date=2023-12-04 }}</ref>

These occurrences emphasize the importance of protective measures for workers. The [[Centers for Disease Control and Prevention|CDC]] advises that those who work in potentially hazardous environments reduce their exposure as much as possible following the [[hierarchy of hazard controls]].<ref name=":1" /> They recommend that any build-up of bird and bat droppings should be avoided if possible, but if it is unavoidable, various engineering, administrative controls, and [[personal protective equipment]] can be implemented in the workplace.<ref name=":2">{{cite web |title=HEALTH HAZARDS ASSOCIATED WITH BIRD AND BAT DROPPINGS |url=http://www.idph.state.il.us/public/hb/hbb&bdrp.htm |access-date=2023-12-04 |website=www.idph.state.il.us}}</ref> The CDC also suggests that workplaces should be responsible for administrative controls such as developing a safety plan, posting notice of the risk of exposure, disposing of any potentially contaminated materials, and providing proper education on the dangers associated with histoplasma.<ref name=":1" /> Adequate personal protective equipment includes a respirator, hooded coveralls, shoe coverings, gloves, and eye protection.<ref name=":2" />

==History==
''Histoplasma'' was discovered in 1906 by [[Samuel T. Darling]],<ref name=Darling1906>{{cite journal | vauthors=Darling ST| title=A protozoan general infection producing pseudotubercles in the lungs and focal necrosis in the liver, spleen and lymphnodes| journal=J Am Med Assoc| volume=46| issue=17| pages=1283–5| year=1906|url=http://www.bium.univ-paris5.fr/histmed/medica/cote?epo0215| doi=10.1001/jama.1906.62510440037003| url-access=subscription}}</ref> but only in the 1930s was it discovered to be a widespread infection. Before then, many cases of histoplasmosis were mistakenly attributed to tuberculosis, and patients were mistakenly admitted to tuberculosis sanatoria.  Some patients contracted tuberculosis in these sanatoriums.<ref>{{cite book | vauthors = Bennett JE, Dolin R, Blaser MJ | title = Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases | edition = 8th | date = 11 September 2014 | publisher = Elsevier Health Sciences | isbn = 978-1-4557-4801-3 }}</ref>

==Society and culture==
* [[Francis D. Culkin]] Member of the [[U.S. House of Representatives]] from New York's 32nd district, died from the disease on August 4, 1943.
* [[Johnny Cash]] included a reference to the disease, even correctly noting its source in bird droppings, in the song "Beans for Breakfast".<ref>{{cite web|last1=Kroll|first1=David|title=Solving The Mystery Of 'Bamboo Bonfire' Lung Disease|url=https://www.forbes.com/sites/davidkroll/2014/03/06/solving-the-mystery-of-bamboo-bonfire-lung-disease/2/ |website=Forbes|access-date=2017-11-04|language=en|date=6 March 2014}}</ref>
* [[Bob Dylan]] was hospitalized due to histoplasmosis in 1997, causing the cancellation of concerts in the United Kingdom and Switzerland.<ref>{{cite web|url=http://www.cnn.com/SHOWBIZ/9705/28/dylan.ill/ |archive-url=https://web.archive.org/web/20071026092311/http://www.cnn.com/SHOWBIZ/9705/28/dylan.ill/|title=CNN - Bob Dylan hospitalized with histoplasmosis|website=[[CNN]] |archive-date=October 26, 2007}}</ref>
* In [[Family (House)|episode 21 of season three]] of the television series ''[[House (TV series)|House M.D.]]'', a patient was diagnosed with histoplasmosis.{{citation needed|date=January 2023}}
* In [[List of New Amsterdam episodes#Season 1 (2018%E2%80%9319)|episode 4 of season one]] of the television series ''[[New Amsterdam (2018 TV series)|New Amsterdam]]'', a critically ill patient was diagnosed with histoplasmosis which he was denying to visit hospital because he was homeless.
* In [[Love American Style (Dexter)|episode five of season one]] of the television series ''[[Dexter (TV series)|Dexter]]'', [[Vince Masuka]] gets worried about getting histoplasmosis from the dust in the air and the hair of the rats.{{citation needed|date=January 2023}}
* In episode 5 of season 5 of ''[[Monsters Inside Me]]'', "There's a Worm Crawling In My What?" (aired November 13, 2014), a video game programmer, Cody Fry, was infected with the disease. He survived his initial bout with disease up to the premiere of the episode, but he died from the illness less than a year after the episode premiered, on October 23, 2015.<ref>{{cite web|last1=Ottier|first1=Morgan|title=Midwest Fungus, Deadly Disease: A Young Man's Fight For His Life|url=https://www.kwqc.com/content/news/Midwest-Fungus-Deadly-Disease-A-young-mans-fight-for-his-life-415321433.html|website=KWQC|access-date=2022-10-30|language=en|date=3 March 2017}}</ref>
* In the [[BBC]] drama ''[[Call The Midwife]]''<nowiki />'s 9th season, a character is diagnosed with the disease after initial confusion regarding whether his symptoms were more indicative of tuberculosis. He contracts it from the droppings of pet pigeons he keeps in his home.{{citation needed|date=January 2023}}

== References ==
{{Reflist}}

== External links ==
* {{CDCDiseaseInfo|histoplasmosis}}
{{Medical resources
|  DiseasesDB      = 5925
|  ICD10           = {{ICD10|B|39||b|35}}
|  ICD9            = {{ICD9|115}}
|  ICDO            =
|  OMIM            =
|  MedlinePlus     = 001082
|  eMedicineSubj   = med
|  eMedicineTopic  = 1021
|  eMedicine_mult  = {{eMedicine2|ped|1017}}
|  MeshID          = D006660
|  Orphanet        = 390
}}
{{Diseases of the skin and appendages by morphology}}
{{Mycoses}}

[[Category:Mycosis-related cutaneous conditions]]
[[Category:Zoonoses]]
[[Category:Animal fungal diseases]]
[[Category:Bird diseases]]
[[Category:Cat diseases]]
[[Category:Dog diseases]]
[[Category:Fungal diseases]]