Monitoring the treatment of sepsis with vancomycin in term newborn infants

Abstract

A prospective study was conducted to determine if standardized vancomycin doses could produce adequate serum concentrations in 25 term newborn infants with sepsis. Purpose: The therapeutic response of neonatal sepsis by Staphylococcus sp. treated with vancomycin was evaluated through serum concentrations of vancomycin, serum bactericidal titers (SBT), and minimum inhibitory concentration (MIC).Method: Vancomycin serum concentrations were determined by the fluorescence polarization immunoassay technique , SBT by the macro-broth dilution method, and MIC by diffusion test in agar .Results: Thirteen newborn infants (59.1%) had adequate peak vancomycin serum concentrations (20-40 mg/mL) and one had peak concentration with potential ototoxicity risk (>40 µg/mL). Only 48% had adequate trough concentrations (5-10 mg/mL), and seven (28%) had a potential nephrotoxicity risk (>10 µg/mL). There was no significant agreement regarding normality for peak and trough vancomycin method (McNemar test : p = 0.7905). Peak serum vancomycin concentrations were compared with the clinical evaluation (good or bad clinical evolution) of the infants, with no significant difference found (U=51.5; p=0.1947). There was also no significant difference between the patients' trough concentrations and good or bad clinical evolution (U = 77.0; p=0.1710). All Staphylococcus isolates were sensitive to vancomycin according to the MIC. Half of the patients with adequate trough SBT (1/8), also had adequate trough vancomycin concentrations and satisfactory clinical evolution.Conclusions: Recommended vancomycin schedules for term newborn infants with neonatal sepsis should be based on the weight and postconceptual age only to start antimicrobial therapy. There is no ideal pattern of vancomycin dosing; vancomycin dosages must be individualized. SBT interpretation should be made in conjunction with the patient's clinical presentation and vancomycin serum concentrations. Those laboratory and clinical data favor elucidation of the probable cause of patient's bad evolution, which would facilitate drug adjustment and reduce the risk of toxicity or failing to achieve therapeutic doses.

Inadequate vancomycin therapy in term and preterm neonates: a retrospective analysis of trough serum concentrations in relation to minimal inhibitory concentrations

“…Therapeutic trough vancomycin concentrations range from 5 mg/L to 25 mg/L [8,12]. Thus, reports on the number of subjects with sub-therapeutic levels of vancomycin show wildly varying results, with reported percentages ranging from 24% to 58% [13,14]. In the present study, approximately half of the neonates had initial trough serum concentrations in the sub-therapeutic range after the administration of the recommended dosing regimen.…”

Clinical Efficacy of Therapeutic Drug Monitoring in Patients Receiving Vancomycin

“…1,15,19,20) A study on the relationship between peak concentrations of VCM and the therapeutic response in the newborn infants with bacteremia showed that the median peak VCM concentrations were 27.4 mg/ml and 16.4 mg/ml in the patients with good and bad evolution, respectively. 21) However, these differences were not significant. In the present study, the duration of treatment for the TDM Group A, in which the peak VCM concentrations within 10 d of Day 1 were 25 mg/ml or above, was significantly shorter than that of the Group B, in which the peak concentrations were below 25 mg/ml.…”

Evaluation of safety and pharmacokinetics of vancomycin after intravenous regional limb perfusion in horses

“…[29][30][31] However, results of studies [31][32][33][34] in human patients and experiments with animal models indicate that measurement of blood urea and serum creatinine over a period of 5 days accurately detects changes associated with nephrotoxicosis.…”