Presence of urinary symptoms in bacteremic urinary tract infection: a retrospective cohort study of Escherichia coli bacteremia

Abstract

Background: It is important to understand clinical features of bacteremic urinary tract infection (bUTI), because bUTI is a serious infection that requires prompt diagnosis and antibiotic therapy. Escherichia coli is the most common and important uropathogen. The objective of our study was to characterize the clinical presentation of E coli bUTI.

Methods: Retrospective cohort study of consecutive adult patients admitted for community acquired E. coli bacteremia from January 1, 2015 to December 31, 2016 was conducted at 4 acute care academic and community hospitals in Toronto, Ontario, Canada. Logistic regression models were developed to identify E coli bUTI cases without urinary symptoms.

Results: Of 462 patients with E. coli bacteremia, 284 (61.5%) patients had a urinary source. Of these 284 patients, 161 (56.7%) had urinary symptoms. In a multivariable model, bUTI without urinary symptoms were associated with older age (age < 65 years as reference, age 65-74 years had OR of 2.13 95% CI 0.99-4.59 p = 0.0523; age 75-84 years had OR of 1.80 95% CI 0.91-3.57 p = 0.0914; age > =85 years had OR of 2.95 95% CI 1.44-6.18 p = 0.0036) and delirium (OR of 2.12 95% CI 1.13-4.03 p = 0.0207). Sepsis by SIRS criteria was present in 274 (96.5%) of all bUTI cases and 119 (96.8%) of bUTI cases without urinary symptoms.

Conclusion: The majority of patients with E. coli bacteremia had a urinary source. A significant proportion of bUTI cases had no urinary symptoms elicited on history. Elderly and delirious patients were more likely to have bUTI without urinary symptoms. In elderly and delirious patients with sepsis by SIRS criteria but without a clear infectious source, clinicians should suspect, investigate, and treat for bUTI.

Keywords: Bacteremia; Diagnosis; Escherichia coli; Urinary tract infection.

Fig. 1

Flow diagram of patients included in this study