Primary Rifampicin Mono-Resistant Extrapulmonary Tuberculosis of the Knee Without Pulmonary Involvement: One of the First Cases of Its Type in an Immunocompetent Male

Tuberculosis presentation at sites other than the lungs is relatively infrequent, and isolated knee involvement without a pulmonary focus is exceptionally rare. Furthermore, there have been no reported cases of primary rifampicin mono-resistant extrapulmonary tuberculosis of the knee in males. In this case, a 24-year-old male patient presented with pain and swelling in his left knee after a fall five years ago. Given the absence of a history of tuberculosis, arriving at a diagnosis posed a significant challenge. However, the diagnosis was ultimately established through cartridge-based nucleic acid amplification tests and clinical link-up with radiometric techniques. Management was based on the latest national guidelines for anti-tuberculous treatment, which were tailored to his weight. To date, he has completed nine months of treatment with a significant improvement in his symptoms. This rare presentation emphasizes the need for a high degree of suspicion even in extrapulmonary tuberculosis cases.