Tuberculosis-immune Reconstitution Inflammatory Syndrome

An 87-year-old woman with hypertension and hyperlipidemia complained of dyspnea and a fever. Computed tomography (CT) revealed a left-sided pleural effusion, revealing a lymphocytic exudate with 74.3 IU/L of adenosine deaminase, and spondylodiscitis in the Th6 segment (Picture A, B). Sputum culture revealed Mycobacterium tuberculosis without drug resistance. We started antituberculosis therapy with isoniazid (200 mg/day), rifampin (450 mg/day), and ethambutol (750 mg/day) with good adherence. Her fever recurred two weeks following antituberculosis therapy initiation. One month later, CT revealed a new mass in the right upper lobe that was positive on tuberculosispolymerase chain reaction (assessed using CT-guided biopsy) and progressive spondylodiscitis (Picture C, D). Five months later, CT showed that the mass in the right upper lobe had shrunk in size with progressive spondylodiscitis (Picture E, F). We diagnosed this clinical course as tuberculosis-immune reconstitution inflammatory syndrome (IRIS). Tuberculosis-IRIS is not a rare phenomenon; however, it can be misdiagnosed as superimposed infections, treatment failure, or tuberculosis relapse (1).