Non-touch aseptic technique maintains sterility of antibiotic-admixed peritoneal dialysis fluid

There is a paucity of data on the sterility of peritoneal dialysis fluid (PDF) after drug admixture. International Society for Peritoneal Dialysis (ISPD) guidelines suggest using sterile technique when admixing antibiotics; however, the degree of sterility remains unclear. This issue is most pertinent when preparing take-home PDF for outpatient treatment of peritonitis. This study compares the sterility of PDF admixed with antibiotics using a non-touch aseptic technique (NTAT) versus sterile technique. Groups of 8 PDF mixtures (1.5% Dianeal or Icodextrin [Baxter International Inc., Spring Grove, IL, USA]) were admixed with 1 g/L ceftazidime and vancomycin, or 20 mL saline, either by a pharmacist using sterile technique in a sterile suite, or a nurse in a clinical room using NTAT. Dianeal inoculated with 1 × 10⁶ colony-forming units (CFU)/L of coagulase-negative Staphylococcus (CNS), with and without antibiotics, served as positive controls. Admixed PDFs were left at room temperature for 72 hours, then cultured using the BacT/ALERT system. A positive culture by day 5 constituted a contamination. Differences in proportion of contamination between groups were assessed using the Chi-squared test. Eighty PDF bags underwent microbiological testing. Sterility was maintained in all bags, independent of technique (NTAT versus sterile technique), type of PDF (Dianeal versus Icodextrin), or whether antibiotics were admixed. Of the positive controls, CNS-inoculated PDFs without antibiotics were all culture positive; however, when inoculated into antibiotic-admixed PDFs, only S. haemolyticus remained culture-positive (p < 0.0001). In conclusion, PDF sterility can be maintained using NTAT for up to 3 days at room temperature. Currently, there is insufficient evidence to adopt sterile technique in sterile suites when admixing take-home PDF.