Asymptomatic bacteriuria in older adults: the most fragile women are prone to long-term colonization

• Published in: BMC geriatrics Vol. 19; no. 1; pp. 170 - 11
• Main Authors: Biggel, Michael, Heytens, Stefan, Latour, Katrien, Bruyndonckx, Robin, Goossens, Herman, Moons, Pieter
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 21.06.2019; BioMed Central; BMC
• Subjects: Aged; Aged, 80 and over; Analysis; Anti-Bacterial Agents - pharmacology; Anti-Bacterial Agents - therapeutic use; Antibiotics; Asymptomatic bacteriuria; Asymptomatic Infections - epidemiology; Asymptomatic Infections - therapy; Bacteriuria; Bacteriuria - diagnosis; Bacteriuria - drug therapy; Bacteriuria - epidemiology; Complications and side effects; Decision making; Diagnosis; Elderly women; Escherichia coli - drug effects; Escherichia coli - physiology; Escherichia coli Infections - diagnosis; Escherichia coli Infections - drug therapy; Escherichia coli Infections - epidemiology; Female; Frail Elderly; Gerontology; Health aspects; Humans; Incontinence; Infection; Long term care; Long term care facilities; Nursing Homes - trends; Older adults; Prevalence; Risk factors; Time Factors; Treatment outcome; Urinary incontinence; Urinary tract infection; Urinary tract infections; Urinary Tract Infections - diagnosis; Urinary Tract Infections - drug therapy; Urinary Tract Infections - epidemiology; Women; Asymptomatic bacteriuria; Older adults; Urinary tract infection
• ISSN: 1471-2318; 1471-2318
• DOI: 10.1186/s12877-019-1181-4

The diagnosis of urinary tract infections (UTIs) in institutionalized older adults is often based on vague symptoms and a positive culture. The high prevalence of asymptomatic bacteriuria (ABU), which cannot be easily discriminated from an acute infection in this population, is frequently neglected, leading to a vast over-prescription of antibiotics. This study aimed to identify subpopulations predisposed to transient or long-term ABU. Residents in a long-term care facility were screened for ABU. Mid-stream urine samples were collected during two sampling rounds, separated by 10 weeks, each consisting of an initial and a confirmative follow-up sample. ABU occurred in approximately 40% of the participants and was mostly caused by Escherichia coli. Long-term ABU (> 3 months) was found in 30% of the subjects. The frailest women with urinary incontinence and dementia had drastically increased rates of ABU and especially long-term ABU. ABU was best predicted by a scale describing the functional independence of older adults. Institutionalized women with incontinence have ABU prevalence rates of about 80% and are often persistent carriers. Such prevalence rates should be considered in clinical decision making as they devalue the meaning of a positive urine culture as a criterion to diagnose UTIs. Diagnostic strategies are urgently needed to avoid antibiotic overuse and to identify patients at risk to develop upper UTI.