Blastomycosis

Not to be confused with chromoblastomycosis. For "South American blastomycosis", see paracoccidioidomycosis. For "European blastomycosis", see cryptococcosis.
Blastomycosis
Other namesBlasto,[1] North American blastomycosis,[2] Chicago disease[3]
Lung infiltration in blastomycosis.
SpecialtyInfectious disease[4]
Symptoms
CausesBlastomyces dermatitidis[2]
TreatmentAntifungals[6]
MedicationItraconazole, amphotericin B[6]

Blastomycosis, also known as Gilchrist's disease, is a fungal infection, typically of the lungs, which can spread to brain, stomach, intestine and skin, where it appears as crusting purplish warty plaques with a roundish bumpy edge and central depression.[2][7] Around half of people with the disease have symptoms, which can include fever, cough, night sweats, muscle pains, weight loss, chest pain, and fatigue.[5] Symptoms usually develop between three weeks and three months after breathing in the spores.[5] In 25% to 40% of cases, the infection also spreads to other parts of the body, such as the skin, bones or central nervous system.[8] Although blastomycosis is especially dangerous for those with weak immune systems, most people diagnosed with blastomycosis have healthy immune systems.[8]

Blastomyces dermatitidis is found in the soil and decaying organic matter like wood or leaves.[6] Outdoor activities like hunting or camping in wooded areas increase the risk of developing blastomycosis.[9] There is no vaccine, but the risk of the disease can be reduced by not disturbing the soil.[9] Treatment is typically with an azole drug such as itraconazole for mild or moderate disease.[10] In severe cases, patients are treated with amphotericin B before azole treatment.[10] In either event, the azole treatment lasts for 6–12 months.[11] Overall, 4–6% of people who develop blastomycosis die; however, if the central nervous system is involved, this rises to 18%. People with AIDS or on medications that suppress the immune system have the highest risk of death at 25–40%.[12]

Blastomycosis is endemic to the eastern United States and Canada, especially the Ohio and Mississippi River valleys, the Great Lakes, and the St. Lawrence River valley.[6] In these areas, there are about 1 to 2 cases per 100,000 per year.[13] Less frequently, blastomycosis also occurs in Africa, the Middle East, India, and western North America.[8][14] Blastomycosis also affects a broad range of non-human mammals, and dogs in particular are an order of magnitude more likely to contract the disease than humans.[15] The ecological niche of Blastomyces in the wild is poorly understood, and it is unknown if there are any significant host animals.[16]

Blastomycosis has existed for millions of years but was first described by Thomas Caspar Gilchrist in 1894. Because of this, it is sometimes called "Gilchrist's disease".[17]

  1. ^ Lamb, Vickie (2011). The Ultimate Hunting Dog Reference Book: A Comprehensive Guide to More Than 60 Sporting Breeds. Simon & Schuster. ISBN 9781634504621.
  2. ^ a b c d Johnstone, Ronald B. (2017). "25. Mycoses and Algal infections". Weedon's Skin Pathology Essentials (2nd ed.). Elsevier. p. 449. ISBN 978-0-7020-6830-0.
  3. ^ Calderone, Richard (2002). Fungal Pathogenesis: Principles and Clinical Applications. Boca Raton: CRC Press. doi:10.1201/9781482270907. ISBN 9780429153228.
  4. ^ "ICD-11 – ICD-11 for Mortality and Morbidity Statistics". icd.who.int. Retrieved 29 May 2021.
  5. ^ a b c "Symptoms of Blastomycosis". cdc.gov. 2019-01-29. Archived from the original on 26 April 2019. Retrieved 15 May 2019.
  6. ^ a b c d "Information for Healthcare Professionals about Blastomycosis". cdc.gov. 2019-01-24. Archived from the original on 26 April 2019. Retrieved 15 May 2019.
  7. ^ "Blastomycosis". cdc.gov. Centers for Disease Control and Prevention. 9 February 2022. Retrieved 2022-05-14.
  8. ^ a b c McBride, Joseph A.; Gauthier, Gregory M.; Klein, Bruce S. (September 2017). "Clinical manifestations and treatment of blastomycosis". Clinics in Chest Medicine. 38 (3): 435–449. doi:10.1016/j.ccm.2017.04.006. PMC 5657236. PMID 28797487.
  9. ^ a b "Blastomycosis Risk & Prevention". cdc.gov. 2019-01-29. Archived from the original on 26 April 2019. Retrieved 22 May 2019.
  10. ^ a b Cite error: The named reference idsa2008 was invoked but never defined (see the help page).
  11. ^ "Treatment for Blastomycosis". cdc.gov. 2019-01-29. Archived from the original on 26 April 2019. Retrieved 22 May 2019.
  12. ^ Castillo CG, Kauffman CA, Miceli MH (March 2016). "Blastomycosis". Infectious Disease Clinics of North America. 30 (1): 247–64. doi:10.1016/j.idc.2015.10.002. PMID 26739607.
  13. ^ "Blastomycosis Statistics". cdc.gov. 2019-01-24. Archived from the original on 26 April 2019. Retrieved 22 May 2019.
  14. ^ Cite error: The named reference schwartz2021 was invoked but never defined (see the help page).
  15. ^ Cite error: The named reference schwartz2018 was invoked but never defined (see the help page).
  16. ^ Baumgardner, Dennis J. (2016). "Blastomyces: Why be dimorphic?". Journal of Patient-Centered Research and Reviews. 3 (2): 61–63. doi:10.17294/2330-0698.1256.
  17. ^ Crissey, John Thorne; Parish, Lawrence C.; Holubar, Karl (2002). Historical Atlas of Dermatology and Dermatologists. Parthenon Publishing Group. p. 86. ISBN 978-1842141007.