Unravelling the Added Value of Urinary Stone Cultures Towards Infectious Complications Following Treatment of Renal Stones

<b>Aim:</b> To explore the association between urinary stone cultures and infectious complications following PCNL. <b>Materials and Methods:</b> An observational case-control study was conducted in patients undergoing PCNL. The assessment included demographic parameters, medical history, urinalysis, and urine culture and blood testing. Pre-operatively, urinary stone samples were collected for cultures. Post-operatively, patients were observed for infectious complications such as fever and/or SIRS. Patients were divided into two groups based on the presence or absence of infected renal calculi. Patient characteristics, stone factors, and intra-operative and post-operative findings were studied in relation to stone culture. Descriptive statistics was used to present the data and the SPSS software was used for analysis. <b>Results:</b> From December 2023 to March 2025, a total of 126 patients were included in the study. A total of 16 patients (12.6%) had a positive stone culture. Statistical significance was found upon the comparison of stone culture with gender (<i>p</i> = 0.046), chronic kidney disease (<i>p</i> = 0.002), pre-operative urine culture (<i>p</i> = 0.001), pre-operative haemoglobin (g/dL) (<0.001), pre-operative S. creatinine (mg/dL) (<i>p</i> = 0.038), stone volume (mm³) (<i>p</i> = 0.012), CROES score (<i>p</i> = 0.023), SIRS (<i>p</i> = 0.001), and AKI (<i>p</i> = 0.021). <b>Conclusions:</b> Infected renal calculi identified by positive stone cultures were strongly associated with infective complications such as fever and SIRS following PCNL. <i>E. Coli</i> was the dominant bacteria present in both bladder urine and renal stone culture. The occurrence of infectious complications despite the administration of pre-operative antibiotics highlights the antibiotic resistance patterns noted among the cultured bacteria. The pre-operative factors identified to be associated with a positive stone culture could potentially be used for predicting infected stones, thereby improving outcomes.