Multifocal extraspinal osteoarticular tuberculosis in a high-burden setting: a case series from Venezuela

Abstract Background Osteoarticular tuberculosis (OATB), a rare manifestation of extrapulmonary tuberculosis (TB), presents a significant diagnostic challenge, often leading to delayed treatment and severe morbidity. Its diverse clinical presentations may mimic more common conditions, particularly in high TB-burden settings where data on extraspinal OATB are scarce. This case series highlights the clinical and diagnostic complexities of multifocal extraspinal OATB in an endemic region. Case presentation We present three cases of culture-negative, multifocal extraspinal OATB from Venezuela, all lacking pulmonary involvement. The patients were a 32-year-old female, a 17-year-old female, and a 14-year-old female. Clinical presentations included chronic joint pain, swelling, and draining osteocutaneous fistulas affecting the malleolar, femoral, hip, and hallux regions. Diagnostic delays ranged from two months to five years due to initial misdiagnoses of bacterial osteomyelitis or bone tumors. Standard diagnostic workups, including plain radiography, computed tomography, and magnetic resonance imaging, revealed non-specific osteolytic lesions. Histopathology showed granulomatous inflammation but was often inconclusive. In all three cases, the definitive diagnosis was established via the Xpert MTB/RIF assay performed on tissue or fistula drainage samples, which detected Mycobacterium tuberculosis DNA. Treatment with standard anti-tuberculous therapy resulted in clinical resolution, though significant sequelae, including leg length discrepancy and digit amputation, occurred in cases with prolonged diagnostic delays. Conclusions This case series underscores the critical importance of maintaining a high index of suspicion for OATB in patients with chronic or multifocal osteoarticular lesions, even in immunocompetent individuals without pulmonary symptoms in TB-endemic areas. The Xpert MTB/RIF assay is an invaluable tool for rapid diagnosis in paucibacillary cases, facilitating timely treatment to prevent irreversible complications and improve patient outcomes.