Blastomycosis in a Renal Transplant Recipient: A Rare Encounter in Rural Appalachia

Blastomycosis is a fungal infection caused by Blastomyces species, which are thermally dimorphic fungi endemic to the midwestern, south-central, and southeastern United States (US). Organ transplant patients are at risk of infection due to long-term immunosuppressive therapy. We present a unique case of blastomycosis in a renal transplant patient residing in a non-endemic region of Appalachia.

A 67-year-old patient with history of tobacco use, atrial fibrillation, type 2 diabetes, hyperlipidemia, and bilateral deceased donor kidney transplantation (DDKT) in 2021, presented to Charleston Area Medical Center's (CAMC), Charleston WV, Emergency Department (ED) for fever and night sweats. Initial workup revealed 39.4 °C temperature with remaining vital signs normal. Corona, parainfluenza, influenza, metapneumovirus, mycoplasma pneumonia, RSV were negative, GI PCR panel was negative for C. difficle, yersinia, campylobacter, giardia, vibrio, norovirus, salmonella, rotavirus. Chest X-ray showed a 2.1 × 1.6 cm nodular density in the left upper lobe (LUL) lobe. White blood cell (WBC) count was elevated at 13000/mcl with a left-sided shift. Subsequent computed tomography (CT) of the chest without contrast demonstrated a 2.7 × 2.1 cm LUL mass. Urine Blastomyces antigen tested positive, prompting the initiation of empiric therapy for blastomycosis. Aspergillus was ruled out initially.

Blastomycosis is a rare occurrence in the US, with annual incidence reported at 1 to 2 cases per 100,000. While transplant recipients are predisposed to acquiring blastomycosis, it remains an infrequent occurrence. In transplant patients presenting with persistent infectious symptoms, blastomycosis and other rare etiologies should be considered to prevent severe complications.