Relationship between oral bacteria and hemodialysis access infection

Controversy exists concerning the association between oral bacteria and infection of hemodialysis (HD) shunts. The purpose of this study was to determine the extent to which oral bacteria are associated with vascular access site infections in a group of HD patients.

Microbial blood culture data for 87 HD patients were collected: 53 via chart review (retrospective), and 34 with newly suspected vascular access infections (prospective). The primary outcome was the nature (i.e., species) of the bacteria recovered from blood cultures of subjects with vascular access infection, specifically those bacteria considered to be oral flora.

The predominant bacteria reported to cause HD vascular access infections were Staphylococcus (48.6%) and Enterococcus (17.6%) species. Most infections occurred in hemodialysis catheters (89%) compared with AV grafts (11%) and AV fistulas (0%). The subclavian venous access (41%) and the internal jugular venous access (38.9%) were more commonly infected than other sites. None of the bacteria identified by blood cultures were considered to be oral flora.

The results suggest that oral bacteria rarely, if ever, cause vascular access infections in hemodialysis patients.