Gastroenteritis Causing Derangement in Kidney Functions: A Prospective Observational Study

Background: Acute gastroenteritis can lead to significant kidney function derangement, but the incidence, risk factors, and outcomes remain incompletely characterized. This study investigated the relationship between gastroenteritis and kidney dysfunction in adult patients. Methods: This prospective observational cohort study enrolled 100 consecutive adult patients with acute gastroenteritis from January to December 2024. Comprehensive clinical, laboratory, and microbiological assessments were performed. Acute kidney injury (AKI) was defined according to KDIGO criteria. Novel biomarkers, including TIMP-2 × IGFBP7, KIM-1, and NGAL, were evaluated for AKI prediction. Renal outcomes were assessed at discharge, 30 days, and 90 days. Results: AKI occurred in 28.0% of patients, with 16.0% Stage 1, 8.0% Stage 2, and 4.0% Stage 3. Bacterial etiology was associated with higher AKI risk compared to viral (OR 3.02, 95% CI 1.24-7.37, p = 0.013), with STEC infection conferring the highest risk (OR 9.53, 95% CI 1.79-50.70, p = 0.002). Independent risk factors for AKI included age ≥65 years (aOR 2.83, p = 0.038), baseline eGFR <80 mL/min/1.73m² (aOR 3.12, p = 0.027), NSAID use (aOR 3.04, p = 0.025), severe dehydration (aOR 6.78, p < 0.001), STEC infection (aOR 7.32, p = 0.025), and symptom duration >3 days (aOR 3.18, p = 0.022). Urinary TIMP-2 × IGFBP7 demonstrated the highest predictive accuracy for AKI (AUC 0.92, 95% CI 0.86-0.98). Complete renal recovery occurred in 53.6% of AKI patients at discharge, 78.6% at 30 days, and 89.3% at 90 days, with recovery rates inversely proportional to AKI severity (p = 0.042). Conclusion: Gastroenteritis-associated AKI is common and influenced by both pathogen-specific and host factors. Novel biomarkers outperform conventional parameters for early AKI prediction. While most patients achieve complete renal recovery, a subset develops persistent dysfunction, particularly following severe AKI.