Comparative Evaluation of Complications in Untreated and Recurrent Urinary Tract Infections

Background: Urinary tract infections (UTIs) are common but can cause severe complications if untreated or recurrent, affecting renal function and antibiotic resistance. This study uniquely uses biomarkers such as CRP, NGAL, IL-6, and TNF-α to predict renal dysfunction and antibiotic resistance, highlighting their clinical significance. Objectives: To compare the complications of untreated and recurrent UTIs concerning renal function, systemic inflammation, oxidative stress, and antibiotic resistance using biomarker analysis. Methods: A comparative study was conducted on 500 adult patients (2022–2023) from two tertiary care hospitals. Patients were categorized into recurrent UTIs (≥3 episodes/year) and untreated UTIs (≥1 month without antibiotics). Biomarkers for renal dysfunction (creatinine, eGFR, NGAL), inflammation (CRP, IL-6, TNF-α, procalcitonin), and oxidative stress (MDA, KIM-1) were analyzed. Multivariate regression and statistical tests assessed predictors and significance. Results: Untreated UTIs were associated with significantly worse renal outcomes (creatinine: 2.1±0.4 mg/dL, eGFR: 54.2±6.1; p<0.001), higher inflammation (CRP: 35.7±5.9 mg/L; procalcitonin: 2.1±0.6 ng/mL; p<0.001), and elevated oxidative stress (MDA: 6.7±1.3 μmol/L). Recurrent UTIs had higher multidrug resistance rates (45% vs 28%, p=0.002). CRP, NGAL, and procalcitonin independently predicted renal dysfunction, while IL-6 and TNF-α were strong predictors of antibiotic resistance. Conclusions: Untreated UTIs pose severe risks for renal health and systemic inflammation, while recurrent UTIs increase antibiotic resistance. Biomarkers offer valuable predictive tools for early intervention, improving patient outcomes.