Background Peritonitis is a frequent complication in peritoneal dialysis. Intraperitoneal administration of antibiotics appears to improve the response to intravenous treatment.

Purpose To describe a case of intraperitoneal administration of vancomycin in a paediatric patient and evolution of plasma levels.

Material and methods Prospective case tracking and collaboration in the identification and interpretation of plasma levels of vancomycin.

Results The case was a 3-month-old girl (4.2 kg) that after cardiac surgery presented with acute tubular necrosis and needed continuous venovenous haemodiafiltration (CVVHDF). After 16 days of CVVHDF, this was changed to peritoneal dialysis. 6 days after initiation of peritoneal dialysis, peritonitis developed, and ceftazidime and vancomycin intraperitoneally were prescribed. Vancomycin was prescribed at a dose of 15 mg/L of dialysate (37.5 mg in each bag of 2.5 L). The first determination of plasma levels of vancomycin (at 24 hours) was 14.63 µg/mL and it was recommended to continue with the same dose. Treatment with intraperitoneal vancomycin continued for 21 days. During that time 11 determinations of plasma levels of vancomycin were made (range 8.19–32.93 µg/mL). A level of 32.93 µg/mL on day 10 of treatment indicated an error in the preparation of the dialysis fluid (presentation of dialysate was modified from 2.5 L to 2 L and the same vancomycin amount was added). Intraperitoneal administration of vancomycin (15 mg/L of dialysis fluid) was effective (negativisation crop) and safe (serum creatinine levels maintained).

Conclusion Intraperitoneal administration of vancomycin is an effective alternative in methicillin resistant microorganism infections in patients undergoing peritoneal dialysis. In paediatric patients, the percentage of absorbed vancomycin is unknown. Monitoring plasma levels allows safe dosage and avoids nephrotoxicity associated with high plasma concentrations of vancomycin.

References and/or acknowledgements Paediatric and Neonatal Dosage Handbook. 22 Edition. American Pharmacists Association.

No conflict of interest