B72-06 Beletacept Blues: A Case of Disseminated Coccidioidomycosis

Abstract Introduction Coccidiomycosis is common in the American southwest, with a wide variety of clinical presentations from asymptomatic, to pulmonary infection, to severe disseminated infection including meningitis. Immunosuppressed patients, particularly solid organ transplant patients, are at increased risk for disseminated infection and its associated substantial morbidity and mortality. As novel immunosuppression medications emerge, it is of particular interest how these fungal infections present and are treated in solid organ transplant patients. Beletacept has emerged as one such novel therapy, particularly due to being useful for adherence and for those with significant toxicities on other regiments. Beletacept has been linked with higher rates of aspergillosis and candidiasis, however there is limited descriptions in the literature of other invasive fungal infections such as coccidiomycosis with patients on this medication. Case Description We present a case of a 43-year-old man living in Arizona with end-stage renal disease secondary to IgA nephropathy, status post kidney transplant on belatacept immunosuppression, who developed disseminated coccidioidomycosis. The patient was initially treated for community-acquired pneumonia without improvement on outpatient antibiotics. Chest CT revealed linear consolidations, ground-glass opacities, and satellite nodules suggestive of atypical infection. Initial bronchoalveolar lavage (BAL) and infectious workup were unrevealing except for an elevated Fungitell, prompting empiric isavuconazole therapy. Following discontinuation of antifungal therapy 3 months later, the patient was re-admitted with recurrent fevers and cough. Repeat CT demonstrated extensive centrilobular nodules and peribronchial consolidation (see figure 1). BAL culture grew Coccidioides immitis, and skin biopsy of new nodular lesions confirmed disseminated disease. He was treated with amphotericin B and fluconazole, later transitioned to posaconazole with clinical improvement. Discussion Belatacept is an immunosuppressive agent increasingly used in renal transplant recipients due to its convenient monthly infusion schedule compared to daily oral regimens. However, some data suggest an association between belatacept therapy and a higher risk of fungal infections in immunocompromised patients. In this population, Coccidioides serologic testing may yield false-negative results due to impaired humoral responses. Some studies indicate that serial testing may later become positive as infection progresses. This case highlights the diagnostic challenges of coccidioidomycosis in immunocompromised transplant recipients. Immunocompromised patients living or traveling to endemic regions of Coccidioides are at increased risk of severe infection and having false negative testing. This patient population would benefit from multiple modalities of testing for Coccidioides to improve diagnosis to guide treatment and thus improve outcomes. This abstract is funded by: None