Incidence and outcomes of patients admitted to emergency departments with urinary tract infections in Denmark: a retrospective cohort study

Abstract

Background: Urinary tract infection (UTI) is a common Emergency Department (ED) diagnosis and cause of hospitalization. This study aimed to assess the incidence of UTI-related referrals and admissions in the Region of Southern Denmark and describe patient demographics, clinical and laboratory findings, readmission rates and mortality. Materials and methods: This retrospective cohort study included all referrals to five EDs in the Region of Southern Denmark from January 1, 2016, to March 19, 2018. Patients aged ≥18 years, with a UTI discharge diagnosis were included. Results: A total of 3,754 individual UTI patients were identified, corresponding to an incidence of 17.6 per 10,000 person-years and an admission rate of 10.8 per 10,000 person-years. Admitted patients were older (median age: 77 years), had more comorbidities, higher CRP and leukocyte levels (p < .001). E. coli was the most frequent pathogen in both urine (66.6%) and blood cultures (53.6%). Admission was associated with male sex (OR 1.32), age 60–80 years (OR 3.07), ≥81 (OR 3.60), Charlson Comorbidity Index (CCI) ≥3 (OR 1.34), qSOFA = 1 (OR 1.56), and initiation of antibiotic treatment (OR 4.08). Thirty-day mortality was 7.4%, with age ≥81 (OR 3.86), CCI ≥3 (OR 2.73), and qSOFA = 3 (OR 5.49) as significant risk factors. Among patients who were not admitted at the initial contact, 5.1% required hospitalization within 30 days. Conclusions: UTIs are a common cause of hospitalization and represent a substantial healthcare burden in Denmark. Older age, male sex, comorbidities, and severe clinical presentations were key predictors of admission and mortality.