Short summary

Urine Tract Infections pose a serious risk for elderly patients, with high misdiagnosis rates using standard dipstick tests. This study assesses the diagnostic value of urinary biomarkers NGAL and IL-6 in 200 patients at Odense University Hospital. Biomarker levels will be compared to urine culture and dipstick tests. Results may improve diagnostic accuracy, reduce antibiotic overuse, and enhance patient outcomes.

Rationale

The aim of this study is to evaluate the predictive and diagnostic value of the urinary biomarkers neutrophil gelatinase-associated lipocalin (NGAL) and interleukin-6 (IL-6), both of which have been identified in the literature as promising for diagnosing urinary tract infections (UTIs). UTIs represent a significant healthcare challenge, particularly for elderly and vulnerable individuals, who can rapidly develop severe, life-threatening illness if medical treatment is not initiated promptly. Symptoms of UTIs in older and frail patients can resemble those of other diseases, highlighting the need for diagnostic tests that can quickly and accurately confirm or rule out a UTI. Currently, urine dipstick tests measuring nitrite and leukocytes are the standard method for acute UTI diagnosis. However, studies have demonstrated a high rate of misdiagnosis using this test, especially in elderly and vulnerable patients, leading to both excessive antibiotic use and cases of severe, life-threatening illness. Research suggests that measuring the concentrations of NGAL and IL-6 in urine may improve UTI diagnostics in elderly and frail individuals. NGAL is locally produced in the urinary tract and rises significantly in response to a UTI, while IL-6 plays a key role in the immune response to acute UTI. However, the diagnostic value of combining IL-6 and NGAL has not yet been fully explored. In this study, we will collect urine samples from 200 patients referred to the emergency department at Odense University Hospital with suspected UTI. The urine samples will be analyzed for NGAL and IL-6 concentrations. Data will be evaluated to determine the predictive and diagnostic value of NGAL, IL-6, and their combination, compared to the gold standard (urine culture) and a modified gold standard defined by the research team. The results will be compared to those obtained from urine dipstick tests. The overall goal is to investigate whether these new biomarkers can provide a more accurate and reliable diagnosis.

Description of the cohort

Cohort Description: All men and women aged 65 and older who are admitted to the Emergency Department (FAM) and subsequently referred for diagnostic evaluation in the medical, A, or L departments, where a urinary tract infection (UTI) is considered as a differential diagnosis (based on nursing/medical assessment) and where urine sampling for a dipstick test is deemed necessary. Patients must be physically and mentally capable of understanding and providing written consent. Exclusion Criteria: Patients who have already started antibiotic treatment prior to evaluation in the Emergency Department (FAM).

Data and biological material

Urine, data of urine sample methoid and data from the patient journale

Collaborating researchers and departments

Emergency Department OUH

• MD, professor AnnMarie Lassen

Research Department of Geriatrics

• MD, Professor Karen Andersen Ranberg