Dr. Ayush PandeyMBBS,PG Diploma

November 28, 2018

June 04, 2022


What is blastomycosis?

Blastomycosis is a rare disease caused by a fungus called Blastomyces dermatitidis. The fungus enters the body while inhaling fungal spores present in moist soil. Blastomycosis affects all the systems of the body, especially the lungs and skin, followed by the urinary system, bones and nervous system. The symptoms of the disease are similar to flu, with the involvement of skin (boils and wart-like eruptions) in the later stage. (Consult a doctor with online treatment app)

What are its main signs and symptoms?

The presenting symptoms of blastomycosis appear between 3 weeks and 3 months after inhaling the spores of the fungus. The symptoms are similar to flu and resolve within a few days. Symptoms are absent in most infected individuals. However, they appear when the infection spreads to different parts of the body, especially in those with a weak immune system.

  • Fever
  • Night sweats or hot flushes at night
  • Cough, sputum mixed with blood when infection spreads to the lungs
  • Chest pain
  • Pain in the joints and muscles
  • Extreme tiredness and general discomfort
  • Weight loss with no definite reason
  • Pneumonia and respiratory distress syndrome are common in severe cases of lung blastomycosis.
  • Symptoms related to skin include lesions on the exposed areas that look similar to warts or ulcers and are grey or violet in colour. They also appear inside the nose or mouth and are generally painless. The boils may bleed easily.
  • Destruction of bone tissue and collection of pus in the bone are common when the infection spreads to the bones.
  • Testes, prostate and epididymis are also affected with blastomycosis.
  • Meningitis occurs when nervous system gets involved in blastomycosis.

What are its main causes?

The fungus named Blastomyces causes blastomycosis. It is usually present in moist soil, decaying wood or on dry leaves. When breathed in, the fungus enters the body and spreads to different parts. Blastomyces is common in the United States, Canada and Africa.

How is it diagnosed and treated?

Doctors diagnose blastomycosis on the basis of history, symptoms, physical examination and different tests.

Laboratory tests include:

  • Culture or growth of the fungus on an artificial medium in the laboratory from skin scrapings or swab taken from throat.
  • Sputum test helps in detection of fungus in the sputum by mixing it with a special chemical (10% potassium hydroxide).
  • Histologic examination is done to visualise the fungus in a sample of affected tissue under a microscope.
  • X-ray chest to detect abnormalities in lungs caused due to the infection.
  • Cerebrospinal fluid analysis to detect the fungus in spinal cord and brain.

Blastomycosis is generally treated with antifungal medicines. Itraconazole and amphotericin B are the antifungal medicines commonly used for treating blastomycosis depending on the severity of the disease. The course of treatment varies from 6 months to a year depending on the immune status of the person and severity of the infection.

(Read more: Fungal infections treatment)


  1. MedlinePlus Medical Encyclopedia: US National Library of Medicine; Blastomycosis
  2. U.S. Department of Health & Human Services. Symptoms of Blastomycosis. Centre for Disease and Prevention
  3. Miceli A, Krishnamurthy K. Blastomycosis. Blastomycosis. StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2019 Jan-
  4. Michael Saccente, Gail L. Woods. Clinical and Laboratory Update on Blastomycosis. Clin Microbiol Rev. 2010 Apr; 23(2): 367–381. PMID: 20375357
  5. Michael Saccente, Gail L. Clinical and Laboratory Update on Blastomycosis. American Society of Microbiology