Acute kidney injury as a predictor of infectious complications after mini-PCNL.

OBJECTIVE

To investigate the incidence, risk factors and clinical consequences of acute kidney injury (AKI) following mini-percutaneous nephrolithotomy (mini-PCNL), with particular focus on its association with postoperative infectious complications.

MATERIALS AND METHODS

A retrospective analysis was conducted on 496 adult patients who underwent mini-PCNL (22 Ch) between February 2020 and April 2025. AKI was defined according to KDIGO criteria as either a ≥ 1.5-fold increase or an absolute increase of ≥0.3 mg/dl in serum creatinine within 72 hours postoperatively. Patients were stratified into AKI and non-AKI groups. Multivariable logistic regression analyses were performed to identify predictors of AKI development and infectious complications.

RESULTS

Surgery was done in spinal anaesthesia in all cases. AKI occurred in 45 patients (9.1%). There was no difference in median surgical time (52.5 vs 55.0 minutes, p = 0.33) between groups. There was no difference between the two groups in gender distribution, median age, body mass index, baseline serum creatinine, rates of comorbidities and stone features. Patients with AKI had significantly higher rates of overall postoperative complications (24.4% vs 7.1%, p < 0.001) and longer hospital stays (4 vs 3 days, p < 0.001). Infectious complications were significantly more frequent in the AKI group, with higher median procalcitonin levels (0.21 vs 0.06 ng/ml, p = 0.03). One patient in the AKI group died from sepsis. Multivariable analysis identified previous PCNL (OR 2.51, 95% CI 1.33-4.72, p < 0.01) and higher baseline serum creatinine (OR 2.00, 95% CI 1.07-3.73, p = 0.03) as independent predictors of AKI. AKI was the only independent predictor of infectious complications (OR 3.47, 95% CI 1.04-11.58, p = 0.04).

CONCLUSIONS

The strong association between AKI and infectious complications, including potential mortality from sepsis, highlights the clinical significance of this underreported complication. Enhanced perioperative monitoring and aggressive management of infectious complications are warranted in patients who develop AKI following mini-PCNL.