Case Presentation: An 82-year-old, Samoan male with history of poorly controlled diabetes, hypertension, COPD, and pulmonary coccidioidomycosis on fluconazole therapy (400 mg/day) was referred to the hospital by his primary doctor for treatment of a left ankle ulcer and cellulitis that had not responded to ten days of outpatient amoxicillin-clavulanate therapy. He had no constitutional symptoms or leukocytosis at the time of admission, but ESR was elevated at 117 mm/hr. MRI indicated severe osteomyelitis involving the entire left talus. He was started on broad-spectrum antibiotics, and underwent a wound exploration and debridement with vacuum-assisted closure. Wound cultures grew Coccidioides immitus. Antibacterial therapy was discontinued, and fluconazole was changed to posaconazole. Vacuum-assisted closure was discontinued in favor of daily wet-to-dry dressing changes, and the patient was discharged to acute rehabilitation.
Discussion: Coccidioidomycosis, commonly known as valley fever, is endemic to the southwestern United States, Mexico and Central/South America. The incidence is on the rise in California, especially in concentrated endemic areas along the central coast. The most common manifestations involve self-limited constitutional or respiratory symptoms. Extrapulmonary disease can manifest as meningo-encephalitis, skin and soft tissue infection, or osteoarticular infection. Persons with diabetes or immune compromise, pregnant women, and Black or Filipino patients are at increased risk for severe pulmonary and disseminated disease. In this case, the patient’s first manifestation of coccidioidomycosis was pneumonia 20 months earlier. The pulmonary infection was successfully treated with fluconazole, but maintenance therapy failed to prevent a metastatic infection. Osteoarticular infections have been shown to be more successfully treated with itraconazole, and posaconazole is a newer azole, which may be used to treat coccidioidomycosis refractory to other azoles. The hospitalist should consider the possibility of failed cocciodiomycosis treatment, especially for patients with risk factors for disseminated disease. In patients with open wounds, used dressings must be handled with extreme caution, as materials contaminated with Coccidioides arthroconidia are a transmission hazard.
Conclusions: Especially in endemic areas, coccidioidomycosis is an important consideration when evaluating atypical presentations of skin infections. The hospitalist may easily mistake it for a more common, conventional, bacterial infections, potentially both delaying effective therapy and exposing patients to unnecessary parenteral antibiotics and hospital days. The hospitalist should be vigilant to consider and rule out primary or metastatic Coccidioides osteoarticular infections early in the clinical evaluation process.