We studied cefotaxime (CTX) and desacetylcefotaxime (dCTX) pharmacokinetics in 19 children (ages, 7 to 16 years) with various degrees of renal function. The patients were stratified into three groups according to 24-h urinary creatinine clearance (CLCR) values: group I, CLCR > 80 ml/min/1.73 m2 (n = 7); group II, CLCR from 30 to 80 ml/min/1.73 m2 (n = 6); and group III, CLCR < 30 ml/min/1.73 m2 (n = 6). A single 50-mg/kg dose of CTX was given intravenously to each patient after which blood and urine samples were collected and analyzed for CTX and dCTX by high-performance liquid chromatography. Safety was assessed by pre-and poststudy blood chemistries and urinalysis. The mean values for total body clearance of CTX for groups I, II, and III were 158.1 ± 38.8, 118.3 ± 50.8, and 84.8 ± 11.7 ml/min/1.73 M2, respectively (P < 0.01). Renal clearance also decreased across groups, I, II, and III, with values of 77.5 ± 20.2, 41.3 ± 18.5, and 11.4 ± 7.7 ml/min/1.73 m2 respectively (P < 0.0001). Both the CTX fraction nonrenally cleared and elimination half-life increased with decreasing renal function. The CTX volume of distribution at steady state was not affected by renal disease. The renal clearance values of dCTX were 146.4 ± 71.4, 64.5 ± 32.1, and 14.4 ± 8.7 ml/min/1.73

Cefotaxime was well absorbed and therapeutic serum concentrations were achieved after intraperitoneal administration. Renal and CAPD clearances for cefotaxime and desacetylcefotaxime were low. Cefotaxime nonrenal clearance was unaffected. Further studies are needed to establish appropriate intraperitoneal dosing guidelines of cefotaxime in pediatric CAPD patients.