Medical Microbiology & Diagnosis

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

Abstract

Sophie E Collier, Holly L Ciesielczuk, Robert J Shorten, Andrew Davenport, Hala Kandil, Jane E Carpenter and Timothy D McHugh

 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. The negative predictive value of the PCR in follow-up fluids was 100%.
Conclusion: The use of 16S rDNA PCR in diagnosis of PDAP needs further study and improved sensitivity before widespread introduction.