Addi-Chek filtration, BACTEC, and 10-ml culture methods for recovery of microorganisms from dialysis effluent during episodes of peritonitis

The Addi-Chek (filtration; Millipore Corp., Bedford, Mass.) and BACTEC (radiometric detection of growth in culture media; Johnston Laboratories, Inc., Towson, Md.) systems were compared with the 10-ml culture (centrifugation) method for the recovery of microorganisms from peritoneal dialysate collected from patients with clinical evidence of peritonitis and containing ≥200 leukocytes per mm³. Both alternate methods were comparable, and results were not significantly different from those of the conventional 10-ml culture method. All systems were adversely affected in their capacity to recover organisms when dialysates had been collected during periods of antimicrobial therapy.