Blastomycosis is an infection caused by breathing in the Blastomyces dermatitidis fungus. The fungus is found in decaying wood and soil.
North American blastomycosis; Gilchrist's disease
You can get blastomyocosis by contact with moist soil, most commonly where there is rotting wood and leaves. The fungus enters the body through the lungs, where the infection starts. The fungus then spreads to other parts of the body. The disease may affect the skin, bones and joints, and other areas.
Blastomycosis is rare. It is found in the central and southeastern United States, and in Canada, India, Israel, Saudi Arabia, and Africa.
The key risk factor for the disease is contact with infected soil. It most often affects people with weakened immune systems, such as those with HIV or who have had an organ transplant. Men are more likely to be affected than women.
You may not have any symptoms if the infection remains in the lungs. The following symptoms can develop if the infection spreads to other parts of the body:
Lung infection may not cause any symptoms. Symptoms may be seen if the infection spreads. Symptoms may include:
- Bone and joint pain
- Chest pain
- Cough (may produce brown or bloody mucus)
- Fever and night sweats
- General discomfort, uneasiness, or ill feeling (malaise)
- Muscle pain
- Unintentional weight loss
Most people develop skin symptoms when the infection spreads. You may get papules, pustules, or nodules on exposed body areas.
- May look like warts or ulcers
- Are usually painless
- Vary in color from gray to violet
- May appear in the nose and mouth
- Bleed easily and form ulcers
Over time, these skin sores can lead to scarring and loss of skin color (pigment).
Exams and Tests
You may not need to take medicine for a mild blastomycosis infection that stays in the lungs. Your doctor may recommend the following antifungal medicines when the disease is severe or spreads outside of the lungs.
Amphotericin B may be used for severe infections.
Follow up regularly with your doctor to make sure the infection does not return.
People with minor skin sores (lesions) and relatively mild lung infections usually recover completely. The infection can lead to death if not treated.
- Large sores with pus (abscesses)
- Return of the infection (relapse or disease recurrence)
- Side effects from drugs such as amphotericin B
When to Contact a Medical Professional
Call your health care provider if you have symptoms of blastomycosis.
Avoiding travel to areas where the infection is known to occur may help prevent exposure to the fungus, but this may not always be possible.
Kauffman CA. Blastomycosis. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine. 24th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 342.
Reviewed By: Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital, Boston, MA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.