RESUMEN
CONTEXT: Although miniaturized percutaneous nephrolithotomy (mPCNL) and retrograde intrarenal surgery (RIRS) are both options for treating >1cm kidney stones, controversies exist on whether one is more effective and safer than the other. OBJECTIVE: To systematically appraise randomized trials comparing the effectiveness and safety of mPCNL and RIRS for treating >1cm kidney stones. EVIDENCE ACQUISITION: A systematic search on PubMed/Medline, Web of Science, Embase, and ClinicalTrials.gov was conducted in August 2020 following the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA). Randomized trials comparing mPCNL and RIRS for >1cm kidney stones, and reporting stone-free rate (SFR), hemoglobin drop, transfusion rate, length of hospital stay (LOS), and/or complications, were included. EVIDENCE SYNTHESIS: Eight studies compared mPCNL and RIRS, but one was not included due to its high risk of bias. SFR was higher for mPCNL (RR: 1.06 [95% coefficient interval {CI}, 1.01-1.10], p=0.008). Hemoglobin drop was higher for mPCNL (mean difference [MD]: 0.35 [95% CI, 0.05-0.65] g/dl, p=0.02); however, transfusion rates were similar (p=0.44). Complication rate was similar between mPCNL and RIRS (p=0.39), and the LOS was higher for mPCNL (MD: 1.11 [95% CI, 0.06-2.16] d, p=0.04). A subgroup analysis of lower pole stones showed that SFR was higher for mPCNL (RR: 1.09 [95% CI, 1.00-1.19], p=0.05). CONCLUSIONS: Both approaches are effective and safe. Among these approaches, mPCNL has a higher SFR than RIRS for overall >1cm renal and lower pole stones, but longer LOS, and a higher hemoglobin drop that does not translate into higher transfusion rates. Complications are comparable. PATIENT SUMMARY: Randomized trials have evaluated whether miniaturized percutaneous nephrolithotomy (mPCNL) or retrograde intrarenal surgery is more effective and safer for treating >1cm stones. After comparing the stone-free rate, hemoglobin drop, transfusion rate, length of hospital stay, and complications between both the approaches, mPCNL was found to be slightly more effective, but both were equally safe.
