Objectives: Urinary tract infection (UTI) is common among older women. However, diagnosis is challenging because of frequent chronic lower urinary tract symptoms, cognitive impairment, and a high... Show moreObjectives: Urinary tract infection (UTI) is common among older women. However, diagnosis is challenging because of frequent chronic lower urinary tract symptoms, cognitive impairment, and a high prevalence of asymptomatic bacteriuria (ASB). Current urine diagnostics lack specificity, leading to unnecessary treatment and antimicrobial resistance. This study aimed to evaluate the diagnostic accuracy of 12 urine biomarkers for diagnosing UTI in older women. Methods: In this case -control study, cases were women >= 65 years with >= 2 new -onset lower urinary tract symptoms, pyuria, and one uropathogen >= 104 CFU/mL. Controls were asymptomatic and classified as ASB (one uropathogen >= 105 CFU/mL), negative culture, or mixed flora. Urine biomarker concentrations were measured through liquid chromatography -mass spectrometry and ELISA. Diagnostic accuracy parameters of individual biomarkers and a biomarker model were derived from receiver operating characteristic curves. Results: We included 162 community -dwelling and institutionalized older women. Five urine inflam- matory biomarkers demonstrated high discriminative ability (area under the curve >= 0.80): interleukin 6, azurocidin, neutrophil gelatinase-associated lipocalin, tissue inhibitor of metalloproteinases 2, and C -X-C motif chemokine 9. Azurocidin exhibited the highest diagnostic accuracy (sensitivity 86% [95% CI 75% -93%] and specificity 89% [95% CI 82%-94%] at 16.7 ng/mmol creatinine). A combined biomarker and pyuria model showed improved diagnostic accuracy in patients with UTI and ASB, compared with pyuria alone. Discussion: We identified several urine biomarkers that accurately differentiated older women with UTI from asymptomatic women, including ASB. These findings represent a potential advancement towards improved diagnostics for UTI in older women and warrant validation in a diverse population. Manu P. Bilsen, Clin Microbiol Infect 2024;30:216 (c) 2023 The Authors. Published by Elsevier Ltd on behalf of European Society of Clinical Microbiology and Infectious Diseases. This is an open access article under the CC BY license (http://creativecommons.org/ licenses/by/4.0/). Show less
Bilsen, M.P.; Aantjes, M.J.; Andel, E. van; Stalenhoef, J.E.; Nieuwkoop, C. van; Leyten, E.M.S.; ... ; Lambregts, M.M.C. 2023
Background: Pre-existing lower urinary tract symptoms (LUTS), cognitive impairment, and the high prevalence of asymptomatic bacteriuria (ASB) complicate the diagnosis of urinary tract infection ... Show moreBackground: Pre-existing lower urinary tract symptoms (LUTS), cognitive impairment, and the high prevalence of asymptomatic bacteriuria (ASB) complicate the diagnosis of urinary tract infection (UTI) in older women. The presence of pyuria remains the cornerstone of UTI diagnosis. However, > 90% of ASB patients have pyuria, prompting unnecessary treatment. We quantified pyuria by automated microscopy and flowcytometry to determine the diagnostic accuracy for UTI and to derive pyuria thresholds for UTI in older women. Methods: Women >= 65 years with >= 2 new-onset LUTS and 1 uropathogen >= 10(4) colony-forming units (CFU)/mL were included in the UTI group. Controls were asymptomatic and classified as ASB (1 uropathogen >= 10(5) CFU/mL), negative culture, or mixed flora. Patients with an indwelling catheter or antimicrobial pretreatment were excluded. Leukocyte medians were compared and sensitivity-specificity pairs were derived from a receiver operating characteristic curve. Results: We included 164 participants. UTI patients had higher median urinary leukocytes compared with control patients (microscopy: 900 vs 26 leukocytes/mu L; flowcytometry: 1575 vs 23 leukocytes/mu L; P < .001). Area under the curve was 0.93 for both methods. At a cutoff of 264 leukocytes/mu L, sensitivity and specificity of microscopy were 88% (positive and negative likelihood ratio: 7.2 and 0.1, respectively). The commonly used cutoff of 10 leukocytes/mu L had a poor specificity (36%) and a sensitivity of 100%. Conclusions: The degree of pyuria can help to distinguish UTI in older women from ASB and asymptomatic controls with pyuria. Current pyuria cutoffs are too low and promote inappropriate UTI diagnosis in older women. Show less
