Carriage rates of enterococci in the dental plaque of haemodialysis patients in Dublin.

The incidence of carriage of enterococci in dental plaque was determined in haemodialysis patients attending three clinics in the Dublin area either as outpatients or as hospitalised patients. Their carriage rates were compared with a University group comprising normal healthy students, academic staff, technicians and ancillary personnel and with a cohort of otherwise healthy toothache patients. The carriage rates among the staffs of the dialysis units also were examined. The overall carriage rates of enterococci of the University group, the toothache patient group, the haemodialysis patients and the dialysis unit staffs did not differ significantly from each other, ranging from 5%-20%. However, the dental plaque of a mainly hospitalised group of haemodialysis patients and their attendant staff at one clinic was colonised to a statistically significant higher degree with enterococci than that of the haemodialysis patients and the staff at the outpatient clinics, both separately and as combined patient and staff groups. Age, sex, a history of recent antibiotic therapy, and elapsed time since the last dental visit did not affect isolation rates to a significant extent. The commonest enterococcus isolated from subjects was Streptococcus faecalis, followed by its variety liquefaciens. Only one subject harboured Streptococcus durans in dental plaque. Ten of the 21 subjects yielding enterococci harboured two different enterococci in their plaque. The isolation of S. faecalis var liquefaciens alone or in combination with S. faecalis did not correlate with subject-history parameters. The findings obtained imply that antibiotic prophylaxis specifically against enterococci may be necessary only for a small number of haemodialysis patients in whom oral carriage of enterococci has been demonstrated bacteriologically.