Coccidioides immitis

Coccidioides immitis

• It is a dimorphic fungus with septate hyphae.
•  Fungus causing endemic mycosis -Coccidioidomycosis

Has two forms.

1. White fluffy mould on most culture media(Sabouraund’s agar)
2. Nonbudding spherical form-a spherule, in host tissue.

• C. immitis reproduces in host tissue by forming small endospores within mature spherules.
• Fungus is identified by its appearance by the formation of thick-walled barrel shaped spores, called arthrospores.

Transmission

• Infection is acquired by dust containing arthrospores.

Clinical manifestations

• Most of the infections are asymptomatic Asymptomatic pulmonary nodule.
• Many persons develop a self limited influenza like fever —> Valley fever or desert rheumatism. – Acute pneumonia
• Chronic fibrocavitatory pneumonia
• Chronic dissemination:

1. Bone
2. Meninges
3. Skin 
4. Joints Subcutaneous tissue

• Most Coccidioides infections have an incubation period from one to four weeks
• Resolve without specific therapy.