Reversible seizures and mental status changes in a dialysis patient on isoniazid preventive therapy

To report a case of reversible seizures and mental status changes in a dialysis patient given preventive isoniazid therapy.

A 66-year-old woman on continuous ambulatory peritoneal dialysis (CAPD) was given isoniazid prophylaxis following a purified protein derivative (PPD) reaction greater than 20 mm in duration. Oral administration of isoniazid 300 mg/d was started and four days later she was admitted to the hospital for confusion, lethargy, and focal seizures that began 24 hours after initiation of therapy. All medications were discontinued with the exception of oral pyridoxine 50 mg/d. Dialysis was withheld to determine if the seizures were medication induced rather than uremia related. Seizures and mental status changes were reversed with pyridoxine. Dialysis was restarted after the symptoms resolved.

Preventive therapy against tuberculosis with isoniazid should be stressed throughout the medical community. Isoniazid has adverse effects including hepatitis and peripheral neuropathy (common) and convulsions (rare). Our experience suggests that additional supplementation with pyridoxine 50 mg/d should be given routinely to prevent adverse reactions in uremic patients.