Clinical characteristics and outcomes of community-onset acute pyelonephritis caused by Escherichia coli in elderly patients

PurposeTo evaluate clinical characteristics and outcomes of community-onset acute pyelonephritis (APN) caused by Escherichia coli in elderly patients.Patients/methodsCases of adult patients with community-onset APN caused by E. coli were collected from 10 referral centres in Korea from November 2006 to August 2007. Demographic, clinical and microbiological data were analysed.ResultsDiabetes mellitus (38% vs 23%, P = 0.036), chills (83% vs 66%, P = 0.015), gastrointestinal symptoms (55% vs 34%, P = 0.008), altered mental status on admission (21% vs 9%, P = 0.032), acute renal failure (17% vs 3%, P = 0.004) and concomitant bacteraemia (34% vs 17%, P = 0.015) were more frequently observed in patients aged ≥ 65 years compared with those aged < 65 years. The overall intergroup mortality rates did not differ. However, diabetes mellitus (OR = 3.54, 95% CI = 1.40–9.00, P = 0.008) and age of ≥ 65 years (OR = 2.34, 95% CI = 1.05–5.19, P = 0.037) were significantly related to a longer duration of hospital stay (≥ 5 days).ConclusionElderly patients with APN have a higher frequency of atypical manifestations, such as gastrointestinal symptoms, altered mental status and longer durations of hospital stays. Age was independently associated with longer duration of hospital stays among patients with APN. Careful diagnosis and appropriate treatment are crucial in the management of elderly patients with APN.