B38.3 Cutaneous coccidioidomycosis

Name of the Condition

• Cutaneous coccidioidomycosis

Summary

Cutaneous coccidioidomycosis is a fungal infection of the skin caused by Coccidioides species. It occurs when the fungus disseminates from the lungs or other primary sites to the skin, resulting in localized or widespread skin lesions. The condition may present as nodules, ulcers, or papules and is more common in individuals with weakened immune systems or those with advanced coccidioidomycosis.

Causes

The infection originates from inhaling airborne spores of Coccidioides fungi, which are endemic to arid regions like the southwestern United States, Mexico, and parts of Central and South America. After initial pulmonary infection, the fungus can spread hematogenously to the skin, leading to cutaneous manifestations.

Risk Factors

• Residence or travel to endemic regions, especially during dry, dusty seasons.
• Immunocompromised states, including HIV/AIDS, organ transplantation, or prolonged corticosteroid use.
• Advanced or disseminated coccidioidomycosis involving other organs.
• Pregnancy, particularly the third trimester.
• Advanced age.

Symptoms

• Skin nodules, papules, or ulcers.
• Painful or non-painful skin lesions.
• Lesions may appear on the face, trunk, or extremities.
• Lesions may ulcerate or drain.
• Systemic symptoms (e.g., fever, weight loss) may accompany severe cases.

Diagnosis

Diagnosis involves clinical evaluation of skin lesions, followed by laboratory confirmation. Skin biopsy with histopathology and fungal culture, or molecular testing (e.g., PCR), can identify Coccidioides organisms. Serologic tests (e.g., complement fixation) may support the diagnosis, especially if disseminated disease is suspected. Imaging of the lungs or other organs may be performed to assess for systemic involvement.

Treatment Options

Treatment typically includes antifungal medications, such as fluconazole or itraconazole, for mild to moderate cases. Severe or disseminated infections may require amphotericin B initially, followed by long-term azole therapy. Duration of treatment depends on the extent of disease and immune status. Surgical debridement may be necessary for large or refractory lesions.

Prognosis and Follow-Up

Prognosis is generally good with appropriate antifungal therapy, especially in immunocompetent individuals. However, immunocompromised patients may experience prolonged or recurrent disease. Follow-up includes monitoring for resolution of skin lesions and systemic symptoms, with repeat serologic or imaging studies as needed. Long-term therapy may be required for severe cases.

Complications

• Chronic skin lesions or scarring.
• Secondary bacterial infection of ulcers.
• Dissemination to other organs (e.g., bones, meninges).
• Treatment failure or relapse in immunocompromised individuals.

Lifestyle & Prevention

• Avoid exposure to dust in endemic areas, especially during dry seasons.
• Wear masks or protective clothing when working with soil (e.g., construction, farming).
• Promptly treat underlying immunocompromising conditions.
• Seek early medical care for respiratory symptoms in endemic regions.

When to Seek Professional Help

• New or worsening skin lesions, especially with fever or weight loss.
• Lesions that ulcerate, drain, or fail to heal.
• Symptoms of systemic infection (e.g., cough, chest pain, headache).
• Exposure to endemic regions with respiratory or skin symptoms.

Tips for Medical Coders

Document the presence and location of skin lesions, as well as any associated systemic involvement, to support the diagnosis of cutaneous coccidioidomycosis. Include details on the extent of disease (e.g., localized vs. disseminated) and any underlying immunocompromising conditions, as these may impact coding and clinical management. Ensure alignment with ICD-10-CM guidelines for fungal infections and skin manifestations.