Prolonged Stability of Antimicrobial Activity in Peritoneal Dialysis Solutions

Abstract

← Objective To evaluate the stability of the antimicrobial chemical and bioactivity of gentamicin, vancomycin, and gentamicin and vancomycin in combination, and the stability of the bioactivity of ceftazidime, admixed in standard peritoneal dialysis solutions and then maintained over a 14-day period at room temperature or under refrigeration. ← Setting Peritoneal dialysis center and microbiology laboratory at a military, teaching medical center. ← Measurements Standard peritoneal dialysate bags admixed with gentamicin, vancomycin, gentamicin and vancomycin in combination, or ceftazidime were stored at either 4°C or 20°C for 14 days. Sequential aliquots were withdrawn and assayed for antibiotic activity by bioassay and, except for ceftazidime, immunoassay for chemical activity. The bioassay was performed using a standardized Kirby–Bauer disc method. Significance was determined by ANOVA and, where the effect size was significant at the p < 0.05 level, the application of the paired t-test or the Wilcoxon signed rank test to the difference in activity between the first and last samples. ← Results Antibiotic concentration by immunoassay did not significantly deteriorate over 14 days for vancomycin or gentamicin when either room temperature or refrigerated samples were studied. By bioassay, gentamicin and ceftazidime, but not vancomycin, lost moderate but significant activity over 14 days when refrigerated bags were assayed (except for an insignificant decrement in gentamicin in the combined vancomycin and gentamicin bags). Bags stored at room temperature, in general, lost significant bioactivity over 14 days, but to levels where clinical efficacy would still be expected. The vancomycin bioassay performed on the combination bags demonstrated a remarkably enhanced bioactivity, presumably reflecting synergy with gentamicin. ← Conclusion These data indicate that the study antibiotics admixed with peritoneal dialysis fluids retain stable chemical activity, whether refrigerated or kept at room temperature, for at least 14 days. A moderate decrement in bioactivity occurred for study antibiotics when stored either refrigerated or at room temperature over 14 days, although clinically significant levels were maintained. The clinical significance of a possible synergy between vancomycin and gentamicin is yet to be determined.

Short-Dwell Cycling Intraperitoneal Cefazolin plus Ceftazidime in Peritoneal Dialysis Patients

“…Concerns about cefazolin and ceftazidime stability when exposed to the warmer for an extended time are alleviated by our stability experiment. Moreover, our in vitro experiment also confirmed that cefazolin and ceftazidime added in the 5-liter bag had a good stability in a refrigerator, similar to results from the previous studies in 2-liter bags (26–32). The prolonged refrigerated antibiotic stability over many days would decrease the required frequency of delivering antibiotic-containing PD fluid to patients who live in remote areas and cannot aseptically add antibiotics to PD solutions by themselves.…”

ISPD Peritonitis Recommendations: 2016 Update on Prevention and Treatment

“…Antibiotics are stable for variable times after being added to the PD solution ( 327 ). Vancomycin is stable for 28 days in dialysis solutions stored at room temperature, although higher ambient temperatures will reduce the duration of stability.…”

Peritoneal Dialysis-Related Infections Recommendations: 2010 Update

“…The Committee recommends center-specific selection of empiric therapy, dependent on the local history of sensitivities of organisms causing peritonitis ( Opinion ). Gram-positive organisms may be covered by vancomycin or a cephalosporin, and gram-negative organisms by a third-generation cephalosporin or aminoglycoside ( Evidence ) (Figure 1) (65-105).…”