Coccidioidomycosis Overview

Coccidioidomycosis ("Valley Fever")

• Cause: Mold in soil, yeast in the body.
• Geographic Distribution: Southwest US (Arizona, Nevada), Mexico, Central America, South America.
• Transmission: Inhalation of airborne spores; rare from solid organ transplants.
• Course: Often subclinical, with spontaneous resolution in ~50% of patients; lifelong immunity often prevents recurrence.
• Risk Factors: Exposure to endemic area, dusty outdoor activities, HIV, diabetes mellitus (DM), advanced age, Black or Filipino ethnicity, and pregnancy.
• Symptoms (General): Fever, fatigue, headache, night sweats, weight loss, joint pain (arthralgias).
• Symptoms (Chest): Productive cough, shortness of breath (dyspnea), coughing up blood (hemoptysis), chest pain.
• Symptoms (Skin): Skin rash like erythema nodosum or erythema multiforme.
• Typical Presentation: May be observed in an Arizona man working in construction.
• Testing: IgM and IgG antibody titers, elevated white blood cells (moderate leukocytosis), and elevated eosinophils (eosinophilia), imaging like X-rays or CT scans.
• Treatment (uncomplicated): Spontaneous resolution common; consider itraconazole (200 mg by mouth twice daily) for 6 months.
• Treatment (progressive): Amphotericin B intravenously until antibody titers decline.

Blastomycosis

• Cause: Mold in soil and water.
• Geographic Distribution: Ohio River Basin, Mississippi River Basin, Great Lakes, and St. Lawrence River regions.
• Transmission: Inhalation of spores, skin trauma (e.g., from lumberjacking/wood-cutting).
• Pathophysiology: Exposure to contaminated soil or decomposing timber, inhalation of spores, skin trauma.
• Incubation period: 30-45 days.
• Symptoms (Pulmonary): Often initially asymptomatic in 50% of cases. When symptomatic, can include fever, sweating, cough, and nocturnal joint pain.
• Symptoms (Dissemination): Potential spread to bones, nervous system, additional lungs, liver, spleen, and kidneys.
• Diagnostic Imaging: Chest X-ray may reveal osteolytic lesions (bone breakdown).
• Diagnostic Testing: Microscopy to detect broad-based budding yeast, skin biopsy, and bone marrow aspirate.
• Treatment: Itraconazole (oral) for 6-12 months.
• Treatment (severe): Amphotericin B.

This quiz provides an overview of Coccidioidomycosis, commonly known as Valley Fever. It covers causes, geographic distribution, transmission methods, symptoms, risk factors, and typical presentations. Ideal for students studying infectious diseases and public health.