OBJECTIVETo compare the effects of different contrast media on the renal function in children, and to investigate the prophylactic efficacy of hydration.

METHODSSixty patients on whom either intravenous pyelography (IVP) or enhanced CT scan was required were divided into high osmolality contrast media (HOCM) group (n = 27) and low osmolality contrast media (LOCM) group (n = 33), and each group was randomly subdivided into hydration group (HG) and non-hydration group (NHG). In HOCM group, HG had 14 cases and NHG had 13 cases; while in LOCM group, HG had 18 cases and NHG had 15 cases. A 1/5-tonic solution at a dose of 20 ml/kg was intravenously given immediately after the exposure to a contrast medium within 3 hours in the HG, while the NHG cases were not given any infusion.

RESULTSThere were no significant difference between HG and NHG in baseline serum creatinin (SCr) and creatinin clearance (Ccr). After exposure, in HOCM group, SCr of NHG (59.71 +/- 12.49) micromol/L significantly increased as compared with baseline (49.91 +/- 6.09) micromol/L (P < 0.05), while Ccr (97.81 +/- 15.10)ml/(min x 1.73 m(2)) decreased compared with baseline (71.33 +/- 7.51) ml/(min x 1.73 m(2)) (P < 0.05). No significant changes of SCr and Ccr were observed in the HG before (48.37 +/- 7.11) micromol/L, (99.81 +/- 15.41) ml/(min x 1.73 m(2)) and after (49.63 +/- 6.84) micromol/L, (88.29 +/- 12.75) ml/(min x 1.73 m(2)) (P > 0.05) the exposure to contrast medium. Contrast medium-associated nephropathy (CAN) was found in 3 cases in NHG (23.1%, 3/13) but none in HG (P > 0.05). In the LOCM group, there was no significant difference in SCr and Ccr before and after the exposure to the contrast media. The incidence of CAN was 6.7% (1/15) in the NHG and 11.1% (2/18) in the HG (P > 0.05). The average increase of SCr in HOCM group was significantly higher than that in LOCM group (Z = -2.42, P < 0.05). The average decrease of Ccr in HOCM group was significantly higher than that in LOCM group (Z = -2.83, P < 0.05). The SCr and Ccr of the 6 CAN cases in both HOCM and LOCM groups returned to baseline level within 2 weeks.

CONCLUSIONS(1) Children can develop reversible CAN after the exposure to high or low osmolality contrast medium. (2) The high osmolality contrast medium seemed to have more serious toxicity in renal function than low osmolality contrast medium. (3) The prophylactic use of hydration can effectively prevent CAN in patients who will expose to high osmolality contrast medium. (4) Children can develop reversible CAN after the exposure to low osmolality contrast medium even after hydration.