title: Asymptomatic bacteriuria in the elderly: high prevalence and high turnover of strains.
abstract: Asymptomatic bacteriuria (ASB) was followed in repeated prevalence surveys in a cohort of non-institutionalized residents (n=330), aged>or=80 y. Urine samples were collected at baseline, and at 6, and at 18 months. Phenotyping (PhenePlate) was performed on isolates of Escherichia coli to evaluate strain relatedness. ASB occurred in 19.0, 19.4, and 19.9% in women, and in 9.4, 9.6 and 7.9% in men, at baseline and at the 6- and 18-months follow-up, respectively, and ASB was found at least once in 37% of women and in 20% of men. Of those with ASB at baseline, 60% also had ASB in the 2 subsequent surveys. Among those with persisting E. coli bacteriuria, 76% and 40%, respectively, carried the same strain at the 6- and 18-months follow-ups. In women, we found that the risk of developing a symptomatic urinary tract infection within 24 months was higher among those with ASB at baseline than in those without bacteriuria (p=0.019). ASB is common and often persistent, but we found a high turnover of strains, indicating a high rate of recolonization.
authors.affiliation: Centre for Clinical Research, Dalarna, Falun, Sweden. nils.rodhe@ltdalarna.se
authors.forename: Nils
authors.initials: N
authors.lastname: Rodhe
authors.forename: Sture
authors.initials: S
authors.lastname: Löfgren
authors.forename: Andreas
authors.initials: A
authors.lastname: Matussek
authors.forename: Malin
authors.initials: M
authors.lastname: André
authors.forename: Lars
authors.initials: L
authors.lastname: Englund
authors.forename: Inger
authors.initials: I
authors.lastname: Kühn
authors.forename: Sigvard
authors.initials: S
authors.lastname: Mölstad
mesh_terms: D000369:Aged, 80 and over; D001437:Bacteriuria / Q000150:complications / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology*; D016009:Chi-Square Distribution; D015331:Cohort Studies; D004756:Enterobacteriaceae Infections / Q000453:epidemiology* / Q000382:microbiology*; D004926:Escherichia coli / Q000302:isolation & purification; D005260:Female; D006801:Humans; D007711:Klebsiella pneumoniae / Q000302:isolation & purification; D008297:Male; D015995:Prevalence; D011513:Proteus mirabilis / Q000302:isolation & purification