Oral Prevalence of Aerobic and Facultatively Anaerobic Gram-Negative Rods and Yeasts in Hospitalised Patients

Abstract

Saline oral rinse samples were obtained from 100 hospitalised patients in Hong Kong to determine the oral point prevalence of aerobic and facultatively anaerobic gram-negative rods (AGNR) and yeasts. AGNR and yeasts were isolated from 59 per cent and 53 per cent of patients respectively. Enterobacteriaceae species comprised 50 per cent of all AGNR with an overall prevalence of 32 per cent. Enterobacteriaceae prevalence rates were higher in patients taking β-adrenergic blocking agents (P < 0.01), angiotensin converting enzyme inhibitors (P < 0.05), combinations of antacids and analgesics (P < 0.05) and combinations of antacids and antibiotics (P < 0.05). In addition, Enterobacteriaceae prevalence was higher in patients hospitalised for longer than 15 days than in those hospitalised for 8–15 days (P < 0.05). Candida albicans comprised 75 per cent of all yeasts isolated. Subjects over 60 years of age had a higher prevalence of yeasts than those under 60 (P < 0.05). Patients wearing dentures (n=25) had a higher oral yeast prevalence (76 per cent) than those not wearing dentures (45 per cent) (P < 0.01). The impact, if any, of the high oral prevalence of AGNR in hospitalised patients on the outcome of their disease processes needs to be ascertained.

Key Words:

• oral prevalence
• gram-negative rods
• yeasts
• hospitalised