This 72-year-old male patient is a known case of end-stage renal failure for the last 2 years secondary to diabetic nephropathy and was on regular hemodialysis three times per week. He was diagnosed as pulmonary tuberculosis 4 months before presentation and started on ethambutol 800 mg every alternate day and pyrazinamide 1200 mg/day for first 2 months, rifampicin 600 mg/day, and INH 300 mg/day with pyridoxine 40 mg/day. He was admitted to the intensive care unit because of deterioration in the level of consciousness 3 days before admission; no other significant history was found.
On examination, the patient was unconscious, could open his eyes to loud voice, with Glasgow Coma Scale of 7, temperature was 37 C; other vital signs were normal, no neck stiffness and other focal neurological sign were recorded, and other system examinations showed unremarkable results. The cerebrospinal fluid analysis was normal; biochemistry test results were normal, apart from renal failure. Also, all septic work up with blood cultures showed negative result. Computed tomography of the brain showed brain atrophy, electroencephalogram showed diffuse slow wave all over the brain. As all septic work up, vascular and organic neurological causes were excluded, an INH toxicity was suspected (there is no INH level in our laboratory); hence, it was stopped and pyridoxine in a dose of 80 mg/day was given through a nasogastric tube. On day 5, the patient was completely conscious and discharged from the intensive care unit on moxifloxacine 400 mg/day as a replacement for INH.