Cryptococcal Osteomyelitis in a Virally Suppressed Adolescent Living With HIV: A Case Report

Cryptococcal neoformans infection of the central nervous system (CNS) is well-documented in Sub-Saharan Africa due to its association with the human immunodeficiency virus (HIV) pandemic. While cryptococcal infections can occur at sites other than the CNS, such as in the bones, these instances are less common and have been inadequately documented in the region. Orthopedic cryptococcal infections arise when the organism is inhaled from the environment and subsequently disseminates from the lungs via the bloodstream to the bones. Due to its low incidence and atypical manifestations, cryptococcal osteomyelitis may be overlooked, leading to delayed treatment and potential complications. This case report describes a 12-year-old female patient who presented with pain and swelling in both knee joints one year after initiating treatment for cryptococcal meningitis, which had been only partially effective. On examination, both knee joints exhibited swelling and tenderness, and imaging revealed bilateral pathological fractures in the distal third of the femurs. Histological analysis demonstrated numerous fungal elements consistent with Cryptococcus neoformans. Treatment was initiated with liposomal amphotericin B at a single dose of 10 mg/kg, in conjunction with flucytosine at 100 mg/kg/day and fluconazole at 1200 mg/day. This was followed by a consolidation phase with fluconazole at 800 mg/day, after which the patient was maintained on fluconazole at 200 mg/day. After 52 weeks of treatment, the patient exhibited a favorable clinical response, with successful union of the fractures. In individuals living with HIV, Cryptococcus neoformans may present atypically with involvement of sites outside the CNS, including the skeletal system. Although cryptococcal osteomyelitis is rare, it should be considered in the differential diagnosis in this population. Favorable outcomes can be achieved with prolonged antifungal therapy.