The Role of 16s rDNA PCR in the Diagnosis of Peritoneal Dialysis-Associated Peritonitis

Abstract

Introduction: Despite recent advances in peritoneal dialysis (PD), peritonitis remains the most common and serious complication. In a significant proportion of patients a pathogen is not cultured. In this study we investigated the use of 16S rDNA PCR to make a bacterial diagnosis. Methods:We used an optimised DNA extraction and 16S rDNA PCR with DNA sequencing to detect pathogens in peritoneal dialysis-associated peritonitis (PDAP).Results: Seventy-one PD fluids from twenty-four patients were analysed. In suspected cases of PDAP, thirteen out of twenty-one patients had a bacterial pathogen cultured and 16S rDNA PCR with DNA sequencing identified one additional pathogen. However 16S rDNA PCR only detected the pathogen in five of the culture-positive fluids. All follow-up samples were culture-negative, but possible pathogens were identified in three samples by the 16S rDNA PCR.In suspected cases of PDAP the sensitivity and specificity of the PCR was calculated as 69% and 63%, respectively. Conclusion:The use of 16S rDNA PCR in diagnosing PDAP needs further study and improved sensitivity before widespread introduction.

A case of Neurospora sitophila causing PD peritonitis

“…He was readmitted the following day with recurrence of abdominal pain and new onset diarrhoea, and a PD WCC of 1280 cells/µL (90% neutrophils). Blood and PD effluent extended cultures (bacterial, mycobacterial and fungal) and bacterial 16S rDNA 3 were negative. CAPD was recommenced with IP cefuroxime and gentamicin in each exchange, as per local antimicrobial policy for treatment of culture-negative peritonitis.…”