Intestinal mucosal permeability of children with cefaclor-associated serum sickness-like reactions.

Although the serum sickness-like reaction (SSLR) in children after the administration of cefaclor has long been recognized, the exact mechanism of cefaclor-associated SSLR remains unclear. This study aims to investigate the association between intestinal mucosal permeability and cefaclor-associated SSLR in children. A total of 82 pediatric patients with upper respiratory tract infection following the cefaclor therapy was divided into cefaclor-associated SSLR positive group and negative group based on the presence or absence of SSLR after taking cefaclor, and 30 healthy volunteers served as control group. Urinary lactulose/mannitol (L/M) ratios and serum diamine oxidase (DAO) levels were determined in all cases on days 7, 9, 11, 13, and 15 after oral administration of cefaclor. The children in the control group were given the same measurements after enrollment in this study. From days 7 to 13, the urinary L/M ratio of children with cefaclor SSLR gradually increased and reached to the highest level of 0.38 ± 0.14 on day 13. Compared with the cefaclor-associated SSLR negative group and control group, urinary L/M ratios increased significantly in the cefaclor SSLR positive group on days 7, 9, 11, 13, and 15 after taking cefaclor, and serum levels of DAO following the treatment of cefaclor increased significantly in children with cefaclor SSLR on days 9, 11, 13, and 15. No significant difference in urinary L/M ratios and serum levels of DAO between SSLR negative group and control group through the entire experiment was observed. In conclusion, administration of cefaclor may induce SSLR in children by increasing the intestinal mucosal permeability and/or affecting the integrity of the intestinal mucosa. Determinations of urinary L/M ratios and serum DAO levels may be helpful for observing or predicting the occurrence of SSLR after administration of cefaclor, which will encourage physicians to proceed with extreme caution when prescribing cefaclor for pediatric patients.