Documented viral peritonitis in peritoneal dialysis patients is rare, although up to 20% of all cases are culture negative (non-fungal, non-bacterial). CMV-infected peritoneal cells may serve as a reservoir for reinfection and/or reactivation of CMV after renal transplantation. CMV-Polymerase Chain Reaction (CMV-PCR) amplification analysis identified CMV-DNA in cells from the peritoneal dialysate of 8 patients (3 culture negative peritonitis from a total of 5 examined) and 5 asymptomatics) out of 17 potential kidney transplant recipients (6 on IPD 16.6 +/- 6 months, range 10-29 months; 11 on CAPD 28.1 +/- 25 months, range 2-81 months). Serum titers (10/17 patients analyzed) of anti-CMV IgG antibodies ranged from < 1:20 to 1:320 (no correlation with CMV-DNA) while anti-CMV IgM antibodies were undetectable. Detection of CMV specific sequences in peritoneal cells in peritoneal dialysis patients by the PCR assay is sensitive (amplification of a 133 bp immediate early CMV gene sequence allows detection of 10 CMV infected cells in a background of 10(5) uninfected peritoneal cells), rapid (1 day visual, 3 days with confirmation by Southern hybridization), specific (no amplification of human embryo and kidney cell DNA, or HSV, EBV, or VZV infected cells) and is non-invasive in IPD/CAPD patients since no additional invasive technique is required.