Abstract Introduction: Untreated urinary tract infections (UTIs) can lead to complications, including renal deterioration due to upper urinary tract involvement. Proteinuria, characterized by excessive protein in the urine, is often indicative of kidney damage. The protein-to-creatinine ratio (P/C ratio) test is a convenient and reliable method for assessing proteinuria. This study aimed to evaluate the urine protein-to-creatinine ratio (UPCR) in UTI patients and its association with renal impairment. Materials and Methods: Eighty patients with confirmed UTI and suspected proteinuria were recruited. Urine screening included pyuria (white blood cell presence) as an initial indicator of UTI, followed by microscopic examination of centrifuged urinary sediments. The urine supernatant was analyzed for protein using the urine strip method. Results: After applying exclusion criteria, forty-six patients (n=46) were included in the statistical analysis. Of these, 26% had normal proteinuria (<15 mg/mM Cr), 35% had moderate proteinuria (15-50 mg/mM Cr), and 39% exhibited severe proteinuria (>50 mg/mM Cr). Patients were categorized into three stages (I, II, and III) with mean creatinine excretion values of 33.9 +/- 13.9 mg/dL, 31.2 +/- 17.2 mg/dL, and 29 +/- 13.6 mg/dL, respectively, all significantly below the reference interval (168 +/- 132 mg/dL). Conclusion: Increased urinary protein excretion correlates with heightened risk of renal complications, a leading factor in mortality. Urinary protein excretion was markedly elevated in Stage III patients. The P/C ratio proved to be a more accurate diagnostic marker within the urine profile, highlighting proteinuria in UTI patients as a potential risk factor for renal impairment. Keywords: proteinuria; protein to creatinine ratio (P/C ratio); urine microprotein (UmiP); urinary tract infection (UTI).

The authors have declared no competing interest.

This study did not receive any funding

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The study protocol was approved by the Institutional Human Ethics Committee (RGCB IHEC) of Rajiv Gandhi University of Health Sciences (registration no: DCGI - ECR/484/Inst/KL/2013, DHR-EC/NEW/INST/2020/477)

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All data produced in the present study are available upon reasonable request to the authors