Routine Metabolic and Inflammatory Biomarkers as Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection

Erol Karavar; Kamil Konur

doi:10.70058/cjm.1992405

Routine Metabolic and Inflammatory Biomarkers as Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection

Abstract

Objective: Urinary tract infection (UTI) can cause transient deterioration of renal function, particularly in patients with comorbidities. Although renal function often improves after successful treatment, factors predicting recovery remain unclear. This study investigated the association between routine metabolic and inflammatory biomarkers and renal recovery following outpatient UTI treatment.

Methods: This retrospective single-center cohort study included adult outpatients diagnosed with UTI (January 2022–June 2023). Demographic, clinical, and laboratory parameters—including glycated hemoglobin (HbA1c), thyroid-stimulating hormone (TSH), vitamin B12, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), and aggregate index of systemic inflammation (AISI)—were collected. Renal recovery was defined as an increase in estimated glomerular filtration rate (eGFR) at the first post-treatment follow-up. A secondary sensitivity analysis applied a stricter threshold (≥10% or ≥10 mL/min/1.73m² increase). Multivariable logistic regression and ROC curve analyses were utilized.

Results: Of 146 patients, 84 (57.5%) demonstrated renal recovery under the primary definition. In multivariable analyses adjusted for clinical confounders and baseline eGFR, lower baseline NLR (OR 0.470, p=0.005) and PLR (OR 0.661, p=0.044) emerged as independent predictors of renal recovery. However, in the sensitivity analysis defining major clinical recovery, all inflammatory biomarkers lost their statistical significance. Furthermore, ROC analyses indicated poor standalone discriminative accuracy for all biomarkers individually (AUC < 0.60).

Conclusion: When adjusted for initial renal reserve, lower NLR and PLR act as independent predictors of modest renal recovery after outpatient UTI treatment. However, they cannot predict major functional improvement and show poor standalone discriminative accuracy. Therefore, these routine biomarkers should complement comprehensive clinical assessment rather than serve as isolated prognostic tools.

Keywords

Ethical Statement

Ethical approval for this study was obtained from the Non-Interventional Clinical Research Ethics Committee of Recep Tayyip Erdoğan University (Date: June 4, 2026, Decision No: 2026/341). Owing to the retrospective study design and the use of anonymized clinical data, the requirement for written informed consent was waived by the Ethics Committee.

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Details

Primary Language

English

Subjects

Internal Diseases, Nefroloji

Journal Section

Research Article

Authors

Erol Karavar ^*
0009-0001-4224-7242
Türkiye

Kamil Konur
0000-0002-9666-8085
Türkiye

Early Pub Date

September 7, 2026

Publication Date

September 30, 2026

Submission Date

July 11, 2026

Acceptance Date

September 3, 2026

Published in Issue

Year 2026 Volume: 3 Number: 3

DOI

https://doi.org/10.70058/cjm.1992405

IZ

https://izlik.org/JA85WY48GH

Cite

RIS / Bibtex

APA

Karavar, E., & Konur, K. (2026). Routine Metabolic and Inflammatory Biomarkers as Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection. Cerasus Journal of Medicine, 3(3), 192-203. https://doi.org/10.70058/cjm.1992405

AMA

1.Karavar E, Konur K. Routine Metabolic and Inflammatory Biomarkers as Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection. Cerasus J Med. 2026;3(3):192-203. doi:10.70058/cjm.1992405

Chicago

Karavar, Erol, and Kamil Konur. 2026. “Routine Metabolic and Inflammatory Biomarkers As Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection”. Cerasus Journal of Medicine 3 (3): 192-203. https://doi.org/10.70058/cjm.1992405.

EndNote

Karavar E, Konur K (September 1, 2026) Routine Metabolic and Inflammatory Biomarkers as Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection. Cerasus Journal of Medicine 3 3 192–203.

IEEE

[1]E. Karavar and K. Konur, “Routine Metabolic and Inflammatory Biomarkers as Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection”, Cerasus J Med, vol. 3, no. 3, pp. 192–203, Sept. 2026, doi: 10.70058/cjm.1992405.

ISNAD

Karavar, Erol - Konur, Kamil. “Routine Metabolic and Inflammatory Biomarkers As Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection”. Cerasus Journal of Medicine 3/3 (September 1, 2026): 192-203. https://doi.org/10.70058/cjm.1992405.

JAMA

1.Karavar E, Konur K. Routine Metabolic and Inflammatory Biomarkers as Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection. Cerasus J Med. 2026;3:192–203.

MLA

Karavar, Erol, and Kamil Konur. “Routine Metabolic and Inflammatory Biomarkers As Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection”. Cerasus Journal of Medicine, vol. 3, no. 3, Sept. 2026, pp. 192-03, doi:10.70058/cjm.1992405.

Vancouver

1.Erol Karavar, Kamil Konur. Routine Metabolic and Inflammatory Biomarkers as Predictors of Renal Recovery Following Outpatient Treatment of Urinary Tract Infection. Cerasus J Med. 2026 Sep. 1;3(3):192-203. doi:10.70058/cjm.1992405