Disposition of ceftazidime after intraperitoneal administration in adolescent patients receiving continuous cycling peritoneal dialysis.

Background: Peritonitis is the single most common complication in children maintained on continuous cycling peritoneal dialysis (CCPD) and a significant cause of morbidity. Recent consensus guidelines for the treatment of peritonitis in children receiving peritoneal dialysis recommend the combined intraperitoneal administration of ceftazidime with either a first-generation cephalosporin or vancomycin. The objective of this study is to determine whether a continuous maintenance dose of intraperitoneal ceftazidime in the absence of a loading dose would maintain adequate serum and dialysate concentrations to be effective in the treatment of peritonitis.

Methods: Five ambulatory patients on CCPD therapy were studied with continuous intraperitoneal administration of ceftazidime (125 mg/L). Blood, dialysate, and urine samples were collected at specified intervals during a 24-hour period. Ceftazidime concentrations were measured by using a high-performance liquid chromatography assay.

Results: Mean serum concentrations at completion of the short rapid cycles and at 24 hours were 28.92 +/- 13.64 and 23.92 +/- 11.93 microg/mL, respectively. Serum bioavailability at 24 hours was 74% +/- 6%. Mean dialysate concentrations at completion of the short rapid cycles and at 24 hours were 87.43 +/- 19.18 and 32.06 +/- 6.27 microg/mL, respectively. All 5 patients achieved serum and dialysate ceftazidime concentrations greater than the mean inhibitory concentration within 4 hours.

Conclusion: In adolescent patients on CCPD therapy, a continuous maintenance dose of intraperitoneal ceftazidime in the absence of a loading dose achieves serum and dialysate levels greater than the mean inhibitory concentration of sensitive organisms within 4 hours that persist for 24 hours.