PHARMACOKINETICS AND BACTERICIDAL ACTIVITY OF A SINGLE DAILY DOSE OF NETILMICIN IN THE TREATMENT OF CAPD-ASSOCIATED PERITONITIS

Single daily dosage of netilmicin is generally accepted in systemic in fections, due to biphasic bactericidal activity and prolonged postanti biotic effect of aminoglycosides. Since little is known about the effi cacy of single daily intraperitoneal application of netilmicin in the treatment of CAPD-associated peritonitis, we conducted this prospectiv e study. Seven patients were treated with a single daily dose of netil micin (loading dose 1.5 mg/kg, followed by 40 mg/21 bag/day). Serum an d intraperitoneal levels as well as bactericidal activity of netilmici n against Acinetobacter baumanii, E-coli and Pseudomonas aeruginosa we re measured for 48 hours. Serum and peritoneal levels widely varied am ong the patients due to different interindividual plasma clearance of netilmicin. The intraperitoneal antibacterial action of netilmicin was decreased, moreover, substantial differences in the bactericidal acti vity were found among the patients. However, with high initial netilmi cin levels sufficient bactericidal activity was found for Acinetobacte r and E-coli, but not for Pseudomonas aeruginosa. Hence, a single dail y dosage of netilmicin can be a suitable treatment of CAPD-associated peritonitis, only if the dose is adapted according to the first serum and peritoneal levels. In infections with Pseudomonas aeruginosa highe r peritoneal levels of netilmicin and the combination with other antib iotics will be needed for a sufficient peritoneal bactericidal activit y.