CHSU Discovery

Abstract:
Coccidioidomycosis is endemic in the western hemisphere, commonly occurring through inhalation of arthroconidia. Sixty percent are asymptomatic, while 40% have pneumonia-like symptoms. Extra-thoracic coccidioidomycosis has an overall incidence of 0.2%. We present a very unusual case of coccidioidomycosis initially testing negative twice for antibodies, later diagnosed through bronchoalveolar lavage (BAL) culture. Additionally, a new-onset thrombocytopenia led to bone marrow biopsy revealing disseminated disease. In highly endemic areas, such as this case occurring in the Central Valley of California, it is vital to have low threshold for performing definitive diagnostic tests regardless of negative serology.

A 62F with ESRD presented due to headaches. Sepsis criteria was met with vitals and leukocytosis. Rales were noted on examination, while chest CT showed left lobe consolidation and scattered small nodules. Patient's community-acquired pneumonia (CAP) was managed with empiric antibiotics while pending work-up. Treatment failure led to suspicion for coccidioidomycosis. Fluconazole was then started. Six days after admission, repeat chest CT revealed a miliary pattern. With worsening clinical picture, patient received amphotericin B despite testing negative twice for serum Coccidioides antibodies. Labs also became significant for thrombocytopenia. Heparin-induced thrombocytopenia (HIT) was ruled out and bone marrow biopsy incidentally revealed small, non-caseating granulomas with rare fungal spherules. Previously cultured BAL from bronchoscopy confirmed growth of Coccidioides immitis. Based on the patient’s presentation and diagnostic findings, she was determined to have disseminated coccidioidomycosis.

Hematogenous dissemination of coccidiomycosis is commonly due to an immunocompromised state, such as ESRD. Oftentimes, antibody testing may be negative. The patient also worsened post-antibiotics. Once empiric therapy has failed, bronchoscopy and culture should be performed in CAP to obtain definitive diagnosis. Due to quick progression and high mortality of severe coccidioidomycosis, clinicians must have a high index of suspicion, especially in areas of high endemicity. Early treatment initiation is warranted for better outcomes.