Comparative efficacy and safety of ultra-mini-percutaneous nephrolithotomy versus standard percutaneous nephrolithotomy for renal calculi: a systematic review and meta-analysis.

OBJECTIVE

Standard percutaneous nephrolithotomy (S-PCNL) remains the gold standard for > 2 cm renal stones but carries hemorrhage/sepsis risks. Ultra-mini-percutaneous nephrolithotomy (UM-PCNL) uses smaller tracts (11-14 Fr vs. 24-30 Fr) to reduce complications, yet efficacy/safety for 1.0-2.5 cm stones remains controversial due to limited evidence. This systematic review and meta-analysis compares UM-PCNL versus S-PCNL regarding stone-free rate (SFR) and overall complication rate to evaluate UM-PCNL's safety and efficacy.

METHODS

PubMed, Embase, Cochrane Library, and Web of Science were systematically searched from inception to December 2024 for studies comparing S-PCNL and UM-PCNL outcomes. Meta-analyses used Review Manager 5.4 with random or fixed-effects models to calculate pooled odds ratios (OR) or mean differences (MD).

RESULTS

Seven randomized controlled trials (RCTs) (628 patients; S-PCNL = 317, UM-PCNL = 311) were included. No significant difference in SFR between UM-PCNL and S-PCNL was observed (P = 0.65). However, compared to S-PCNL, UM-PCNL demonstrated shorter hospitalization duration (P < 0.00001), reduced postoperative hemoglobin (HB) drop (P = 0.0004) and lower risk of overall complication rate (P = 0.0003), calyceal injury (P = 0.008), and postoperative fever (P = 0.04). Operative time, severe hemorrhage, urine extravasation, urinary tract infection, and gross hematuria showed no significant differences (all P > 0.05).

CONCLUSION

For 1.0-2.5 cm stones, UM-PCNL achieves comparable SFR to S-PCNL but offers advantages, including shorter hospitalization, less HB decline, and reduced risks of severe bleeding, calyceal injury, postoperative fever, and overall complications.

PROTOCOL REGISTRATION

The objectives and methodology of this systematic review and meta-analysis were prospectively registered in the PROSPERO international prospective register (Registration ID: CRD42025632409), in accordance with PRISMA-P guidelines to ensure transparency and mitigate reporting bias.