Asymptomatic bacteriuria among the institutionalized elderly.

BACKGROUND

Urinary tract infections (UTI) are the most common type of infection among residents of long-term care facilities (LTCFs). The presence of asymptomatic bacteriuria among LTCF residents brings challenges to onsite health professionals. The aim of this study was to explore the prevalence and related factors of aymptomatic bacteriuria among the institutionalized elderly in Taiwan.

METHODS

In 2002, residents of 2 private LTCFs participated in this study. History taking, anthropometric measurements, and urine and blood samplings were performed by experienced research staff. Urine bacterial culture was performed by a standard procedure; subjects with symptoms indicating UTI were excluded. Repeated urine bacterial culture was performed 1 week after screening tests. Bacteriuria was defined as 1 or more organisms isolated from 2 consecutive urine specimens (> or =10(5) CFU [colony-forming units]/mL). Asymptomatic bacteriuria was defined as identical microorganisms isolated from 2 urine culture specimens taken at 1-week intervals from a subject who was free of UTI symptoms. The presence of asymptomatic bacteriuria and its related factors, such as age, sex, nutritional status, and long-term placement of urinary catheter, were evaluated.

RESULTS

A total of 64 institutionalized Chinese elderly (mean age, 76.2 +/- 9.1 years; male:female, 48:16) were collected. The prevalence of asymptomatic bacteriuria was 57.8% (37/64), and was not associated with age, sex, functional status, long-term foley catheter, or previous UTI history. The most commonly isolated organisms were Escherichia coli (29.7%), Klebsiella pneumoniae (21.6%), Providentia stuartii (16.2%), and Pseudomonas aeruginosa (13.5%). Moreover, 21.6% of them showed multiple organisms. Nutritional status (body mass index, serum levels of albumin, total cholesterol, total lymphocyte count, and hemoglobin) was similar between subjects with or without bacteriuria (p > 0.05).

CONCLUSIONS

Asymptomatic bacteriuria is common among Chinese residents in LTCFs. Escherichia coil was the most commonly cultured bacterium. Presence of asymptomatic bacteriuria was not associated with age, sex, functional status, catheter indwelling, previous history of UTI, or nutritional status of residents in LTCFs.