Nephropathy due to radiocontrast media presents with a wide spectrum of changes from reversible renal dysfunction to oliguria requiring dialysis. Nineteen patients (mean age 4.5 +/- 3.7 years) were included. Mean +/- SD values of the variables obtained before and 48 hours after angiography were the following: plasma creatinine: 0.6 +/- 0.10 and 0.6 +/- 0.16 mg/dl; endogenous creatinine clearance: 76.1 +/- 17.0 and 80.9 +/- 19.3 ml/min/1.73 m2; plasma osmolality: 279 +/- 23 and 298 +/- 39 mOsm/kg H2O; urine osmolality: 429 +/- 225 and 459 +/- 196 mOsm/kg H2O; fractional sodium excretion: 2.1 +/- 1.3% and 2.4 +/- 1.3%; plasma uric acid: 3.9 +/- 1.3 and 3.4 +/- 1.0 mg/dl; urinary AST/creatinine: 5.2 +/- 4.8 and 4.2 +/- 2.6 mU/mg; ALT/creatinine: 16.8 +/- 12.4 and 15.3 +/- 12.6 mU/mg; LDH/creatinine: 52.0 +/- 39.6 and 42.3 +/- 31.5 mU/mg; NAG/creatinine: 20.1 +/- 2.8 and 16.8 +/- 2.3 mU/mg, respectively. The changes in renal function parameters and urinary enzyme levels were insignificant statistically (p > 0.05). In conclusion, iopromid injection at maximum doses of 5 ml/kg does not result in injury to the tubular epithelium leading to increased urinary enzyme levels.