Tuberculosis of the knee.

Tuberculosis is a worldwide problem that has persisted in developing countries and is re-emerging in developed ones. Infectious complications with Mycobacterium tuberculosis have also been reported with increasing frequency. Among these, skeletal and intra-articular infections continue to affect patients and pose a difficult diagnostic problem to physicians and orthopedic surgeons. This is so, as the non-specific clinical presentation which, overlaps with several infectious and non-infectious diseases, and the latency period of this bacteria that can persist up to several years after the initial infection, contribute to diagnosis and management delay. Thus due to the paucity of the disease, physicians should heighten their index of suspicion for diagnosing tuberculosis of the joints especially when faced with recurrent symptoms of what they think is a common problem. In this context, we present a case of a protracted recurrent illness of a knee joint, which was proved by culture to be due to M. tuberculosis. Moreover, the aspects of this disease entity that poses a diagnostic challenge to the treating physician are highlighted together with those that differentiate it from other overlapping diseases such as brucellosis, especially in endemic areas.