An Analysis of Percutaneous Nephrolithotomy (PCNL) Performed at the Institute of Kidney Disease, Pakistan: Stone Clearance and Complications.

BACKGROUND

Percutaneous nephrolithotomy (PCNL) is the preferred treatment for large renal stones, yet variability in outcomes arises from patient-specific factors and institutional practices. Understanding complications and predictors of success is essential to improving procedural efficacy.

OBJECTIVE

This study aimed to evaluate stone clearance rates, complications classified using the Clavien-Dindo system, and predictors of PCNL outcomes, with a focus on improving lower calyx stone clearance.

METHODOLOGY

A retrospective analysis was conducted on 422 PCNL procedures performed from July 2021 to December 2023 at the Institute of Kidney Disease, Hayatabad Medical Complex, Peshawar, Pakistan. Patient demographics, stone characteristics, and postoperative outcomes were analyzed. Stone clearance rates were calculated, and complications were categorized by severity. Associations between patient and stone characteristics and outcomes were tested using Chi-square analysis, with significance set at p < 0.05.

RESULTS

A total of 422 PCNL cases were analyzed, with an overall stone-free rate of 75.82% (320/422). The average patient age was 45.39 ± 12.43 years, with male patients comprising 56.87% of the cohort and a mean BMI of 27.82 ± 4.21 kg/m². Hypertension (21.43%), diabetes mellitus (18.95%), and chronic kidney disease (7.11%) were notable comorbidities. Stones averaged 3.21 ± 1.13 cm in size, predominantly composed of calcium oxalate (35.55%), and were most frequently located in the upper calyx (28.44%). Postoperative outcomes revealed a 21.33% complication rate, with 16.59% classified as minor (Clavien-Dindo Grades I-II) and 4.74% as major (Grades III-IV). Follow-up data showed that 11.83% of patients had residual stone fragments, and 9.48% experienced delayed complications, primarily minor. Stone size and location significantly influenced outcomes, with clearance rates of 80.00% for 2-3 cm stones versus 65.57% for stones >3 cm (p = 0.155). Lower calyx stones had markedly reduced clearance rates (50.00%, p < 0.001) compared to upper (75.00%) and mid-calyx (70.00%) stones, while stones in multiple locations also showed poor clearance (57.69%, p = 0.001). Key predictors of complications included higher BMI and prolonged operative times, emphasizing the need for tailored approaches, technical refinements, and institutional audits to optimize outcomes for anatomically or clinically complex cases.

CONCLUSION

This study highlights the high efficacy of PCNL in managing large renal stones, achieving a stone-free rate of 75.82%. However, the findings underscore the significant challenges associated with lower calyx stones and larger stone sizes, both linked to reduced clearance rates. The Clavien-Dindo classification of complications shows that while minor complications are more frequent, major complications remain a concern, especially in patients with elevated BMI or prolonged operative times. To optimize outcomes, this study recommends refining surgical techniques and adopting technological advancements to improve lower calyx clearance, implementing institutional audits to standardize practices, and personalizing treatment strategies through preoperative risk stratification. Future multicenter prospective studies are needed to validate these findings, further explore predictors of outcomes, and develop comprehensive care protocols addressing anatomical and patient-specific challenges in PCNL procedures.