RESUMO
BACKGROUND: Isolated tuberculosis of the spleen has been described occasionally in literature, mostly in immunosuppressed individuals with various risk factors. Sequestration in the spleen makes such Mycobacterium tuberculosis infection difficult to diagnose. This report describes an extremely rare case of isolated splenic tuberculosis in an immunocompetent individual. CASE PRESENTATION: A 26 year old Kenyan male presented with pyrexia of unknown origin, with negative screening tests for bacterial, fungal and parasitic infections. Ziehl-Neelsen staining and GeneXpert tests were negative for M. tuberculosis. Diagnosis of isolated splenic tuberculosis was made on core biopsy of the spleen. The patient initially worsened upon treatment with antituberculous medication attributable to the 'Paradoxical Reaction' phenomenon, before making full recovery. CONCLUSIONS: This case highlights the need to continuously be on the lookout for tuberculosis especially in unusual presentations, including subsequent paradoxical reaction which may be encountered.