Introduction:
Isoniazid (INH) is bactericidal antibiotic frequently used for the prevention and treatment of tuberculosis. Symptoms of INH intoxication diagnosed in children are rare and AKI are casuistic. The case is presented of a 17-year-old boy who was treated with isoniazid and developed acute kidney injury associated with INH intoxication (creatinine 1.4 mg/dl, GFR 51 ml/min, AKI, grade 2 in AKIN and pRIFLE). First symptoms of intoxication were recurrent seizures, followed by metabolic acidosis (pH 6.83, HCO3 2.3 mmol/l, BE (-28.5) mmol/l), hyperglycaemia 268mg/dl, and features rabdomyolysis (CK max. 144,000 U/l, LDH max 11,134 U/l, mioglobina max. >500 ng/ml, GOT max 2918 U/l, GPT max. 754 U/l). In the treatment, anticonvulsants, intensive hydratation and alkalization with 8.4% NaHCO3 were used. Normalization of renal function (0.7 mg/dl, GFR 102 ml/min) and decreasing parameters of rhabdomyolysis (CK, LDH, aminotransferases) were observed. Side-effects of INH, such as intoxication, are associated with acute kidney injury in patients treated with isoniazid.