Case Report: Central Nervous System Tuberculosis Immune Reconstitution Inflammatory Syndrome in a Non-HIV Patient

Abstract

Tuberculosis immune reconstitution inflammatory syndrome (TB-IRIS) is an abnormal, excessive immune response against live or dead Mycobacteria tuberculosis that may occur during or even after completion of anti-TB therapy, commonly in HIV-infected patients. However, this has also been reported amongst HIV negative patients. We report a case of CNS TB-IRIS in a 57-year-old HIV negative man with miliary TB and tuberculoma. He first presented with 4 months of chronic constitutional symptoms. His symptoms improved on standard anti-TB (isoniazid, rifampicin, ethambutol, pyrazinamide) initially, but he developed worsening left hemiparesis after 1 month of treatment. He was restarted on tapering dose of dexamethasone, and anti-TB was intensified with intramuscular streptomycin for 2 months. His gained full muscle power 4 months later. Serial brain imaging subsequently showed slow treatment response with partial resolution of brain lesions. However, he developed another episode of left hemiparesis with facial asymmetry and slurred speech after 16 months of anti-TB treatment. Repeated MRI brain showed 2 large frontal ring enhancing lesions and lesions in cerebellar hemispheres and vermis regions. Due to diagnostic uncertainties and compressive nature of the brain lesions, craniotomy and excision biopsy of the right frontal lesion were performed. There were no evidence of drug resistant TB and no other brain pathologies were found. Moxifloxacin was added post operatively to achieve better CNS penetration. Patient eventually recovered and achieved full muscle strength of left upper and lower limbs.