title: Influence of carbon dioxide on growth and antibiotic susceptibility of coagulase-negative staphylococci cultured in human peritoneal dialysate.
abstract: Used peritoneal dialysis fluid was collected from patients undergoing continuous ambulatory peritoneal dialysis, and its pH and composition were assessed after incubation in either air or air with 5% CO2. Precipitation of calcium, magnesium, phosphate, and proteins occurred in the dialysis fluid incubated in air at 37 degrees C and was associated with a mean pH increase of 1.23 U. Incubation of dialysis fluid in air with 5% CO2 prevented precipitation and maintained pCO2 and pH levels at those found physiologically. Coagulase-negative staphylococcal strains isolated from patients with peritonitis tended to grow less well in dialysis fluid incubated in air than in dialysis fluid incubated in the carbon dioxide-enriched atmosphere. MICs of cefuroxime, ciprofloxacin, and vancomycin for seven strains of coagulase-negative staphylococci in dialysis fluid were markedly affected by atmosphere type (16 of 21 MICs). Of these 16 atmosphere-dependent MICs, 14 were at least fourfold higher in air than in air with 5% CO2.
authors.affiliation: Department of Microbial Diseases, City Hospital, Nottingham, England.
authors.forename: M H
authors.initials: MH
authors.lastname: Wilcox
authors.forename: D G
authors.initials: DG
authors.lastname: Smith
authors.forename: J A
authors.initials: JA
authors.lastname: Evans
authors.forename: S P
authors.initials: SP
authors.lastname: Denyer
authors.forename: R G
authors.initials: RG
authors.lastname: Finch
authors.forename: P
authors.initials: P
authors.lastname: Williams
mesh_terms: D000388:Air; D001202:Ascitic Fluid / Q000382:microbiology; D001431:Bacteriological Techniques; D002245:Carbon Dioxide; D003470:Culture Media; D015314:Dialysis Solutions; D004352:Drug Resistance, Microbial; D006801:Humans; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000009:adverse effects*; D010538:Peritonitis / Q000382:microbiology; D013203:Staphylococcal Infections / Q000382:microbiology; D013210:Staphylococcus / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification*
chemical_list: D003470:Culture Media; D015314:Dialysis Solutions; D002245:Carbon Dioxide