Isoniazid-Induced Cerebellitis in a Chronic Kidney Disease Patient

Abstract

The bacterial disease tuberculosis (TB), when it affects organs of the body other than the lungs, is called extrapulmonary TB. The treatment regimen includes the drugs isoniazid, rifampicin, pyrazinamide, and ethambutol, of which isoniazid is known to be the most active drug. Adverse drug reactions commonly include immunological as well as drug toxicity effects, with the latter being particularly important in renally impaired patients because of high risk of drug accumulation. Cerebellitis, which is an inflammatory condition that results in cerebellar dysfunction, is a rare complication of isoniazid use. Diagnosis is made after excluding all other possibilities. In the case described here, the extrapulmonary TB patient was a known case of chronic kidney disease (G4). He presented with slurred speech and sedation; magnetic resonance imaging scan showed bilateral fluid-attenuated inversion recovery hyperintensities in the dentate nuclei, indicative of cerebellitis. Dramatic improvement was seen upon replacing Isoniazid with levofloxacin and administration of antioxidants and pyridoxine supplements, which confirmed the diagnosis of isoniazid-induced cerebellitis.