Blastomycosis is a fungal infection caused by inhaling spores of the fungus Blastomyces dermatitidis found in soil and wood. It primarily affects the lungs, causing symptoms ranging from mild to severe, such as cough and fever. Left untreated, it can spread to the skin and other organs. Risk factors include activities disturbing contaminated environments and weakened immunity. Diagnosis involves tests of sputum, blood, tissues or skin. Mild cases may resolve without treatment, while more severe or spread cases require antifungal drugs such as itraconazole or amphotericin B.

1. Blastomycosis

2. Blastomycosis is a rare
fungal infection caused by the
fungus Blastomyces
dermatitidis, which grows in
wood and soil. It is a common
infection among dogs,
particularly in areas where it
is prevalent

3. he disease mainly affects the lungs with
nearly 50% of patients often showing
minimal or no symptoms.
The infection may spread to other parts of
the body.
The skin is most commonly affected and is
involved in about 20-40% of cases.

4. Causes and risk factors
Infection occurs by breathing in the spores that
become airborne when contaminated soil or wood is
disturbed.
Humans and animals such as dogs, rats and cats may
become infected. The disease is rarely transmitted
from human-to-human or animal-to-human. Very
rarely, infection via the skin may occur.

5. Blastomycosis can be found throughout
the world but is most common in south-
central and mid-western USA and Canada.
The annual incidence in these areas is
around 1-2 cases per 100,000 people.

6. Although people of all ages
and sex may become infected,
people with weakened
immune systems such as
those with human immune
deficiency virus infection (HIV)
or organ transplant recipients
are at greater risk of severe
disease and infection
spreading to other parts of the
body.

7. Symptom Pattern Features
Flu-like illness
•Fever, chills, headache, non-productive cough
•Symptoms may resolve within days without
treatment
•May go undiagnosed
Acute illness resembling bacterial pneumonia
•High fever, chills, productive cough, chest pain
•Sputum may be yellowish brown
Chronic illness resembling tuberculosis or lung cancer
•Low grade fever, productive cough, night sweats,
weight loss
•Sputum may be yellowish brown or contain blood
Fast, progressive, severe symptoms resembling acute
respiratory distress syndrome (ARDS)
•High fever, shortness of breath, rapid breathing

8. Cutaneous features of
blastomycosis
Skin lesions are common on
the face, neck and extremities
as the infection spreads from
the lungs to other parts of the
body. One or many lesions
may develop.

9. diagnosis
Laboratory
and radiological studies are
performed to confirm the
diagnosis of blastomycosis.
•Sputum microscopy and
cultures
•Serologic testing
•Chest x-ray and CT scanning
•Tissue and skin biopsy

10. Treatment
Patients with blastomycosis confined to
the lungs and who are not suffering
from severe symptoms may not require
any treatment. Usually symptoms
are self-limiting and the infection clears
spontaneously. Treatment should be
used if infection in the lung worsens.

11. When the infection spreads and skin becomes involved,
spontaneous resolution does not occur and treatment is
necessary.
•itraconazole given orally is the drug of choice in mild-to-
moderate disease involving the lungs, or in disease
involving other organs.
•Amphotericin B via intravenous administration is the
drug of choice for severe or life-threatening blastomycosis
(e.g.
ARDS, CNS involvement, immunocompromised patients).