For patients with solitary kidney calculi, severe obstruction, azotemia, disturbance of water and electrolyte balances, disturbance of the acid-base balance and even acute kidney failure may occur. Therefore, PCNL is the primary treatment to remedy solitary kidney calculi especially for solitary kidney calculi larger than 2 cm. But PCNL generally has severe complications, including peripheral organ damage and bleeding, and intraoperative and postoperative hemorrhaging might also occur. Importantly, the solitary kidney functions in a compensatory state for a long time with a thick cortex, considerable blood waft, and abnormal blood vessels, and it is easy to cause bleeding after puncture dilation.
In recent years, because of the low incidence of complications, RIRS has become the preferred treatment for kidney calculi[9].We already know that both RIRS and PCNL treatments for kidney calculi offer excellent safety[10]. However, due to the lack of RCT research, all urolithiasis guidelines have not yet clearly established treatment principles for patients with solitary kidney calculi. In recent years, several authors have compared the efficacy of PCNL and RIRS in the treatment of solitary kidney calculi[11].Some of these authors pronounced that retrograde calculi removal may be achieved even for larger solitary kidney calculi, generally with PCNL[12–15]༟So results are still inconclusive.
Hence, it is necessary to compare the treatments of RIRS and PCNL by meta-analysis. In this study, we assessed 4 scientific research studies. Through systematic evaluation and meta-analysis, this article compares the efficacies of RIRS and PCNL in the treatment of solitary kidney calculi. Our meta-analysis showed that patients with solitary kidney calculi had comparable fundamental traits. This study compared the short-term follow-up results of patients receiving RIRS with those of patients receiving PCNL.
After analyzing the data, we concluded that the SFR of the PCNL group was higher than that of the RIRS group, as we forecasted(P < 0.05,Fig. 2). The results showed excellent balance without excessive heterogeneity. In the four research, 16-18Fr percutaneous access was performed in PCNL in Thomas Knoll et al. and Yue Wu et al. and Guohua Zeng et al. And Yinghao Sun et al. used 22-24Fr percutaneous access in PCNL. Until now, the concept of Mini-PCNL has not been standardized, main to the truth that sheath diameters underneath 20F are defined as miniaturized. Desai and Giusti demonstrate a higher hemoglobin drop after conventional PCNL compared to Mini-PCNL[16, 17]. But, Li and colleagues prospectively evaluated the systemic reaction to PCNL (30Fr) and Mini-PCNL (14–18Fr) without noticing variations among each strategies[18]. Therefore, the benefit of Mini-PCNL remains undefined and may be problem of in addition studies. But the usage of miniaturized instruments turned into based on the assumption of a decrease morbidity because of reduced tract diameter resulting in an awful lot much less renal trauma, mainly for solitary kidney calculi. Finally, this conclusion is consistent with the conclusions of the four included articles, which means that PCNL might be the more effective way to treat patients with a solitary kidney. The mean operation time was highly heterogeneous(I2 = 95%,Fig. 3). We used Review Manager 5.3.5.0 software to analyze the sensitivity of the mean operation time. The results showed good stability but severe heterogeneity. We thought that although RIRS and PCNL technologies have been widely used in most hospitals, the heterogeneity originated in the different levels of RIRS and PCNL technology proficiency mastered by different urologists in different hospitals. At the same time, we can find that RIRS has longer mean operation time than PCNL in two studies by Guohua Zeng et al. and Yue Wu et al. respectively with Mini-PCNL. But the mean operation time of PCNL in the study by Yinghao Sun et al. who used general PCNL was longer than RIRS instead. For Solitary Kidney Calculi patients, shorter operation time may has better safety.
There were no statistical differences in minor or major complications among the patients treated with RIRS and those treated with PCNL(P > 0.05,Fig. 4;P > 0.05,Fig. 5).Minor complications were defined as Clavien I–II, and major complications were defined as Clavien III–V[19].In the four articles analyzed, none of the postoperative patients developed Clavien V complications. Similarly, Thomas Knoll et al. and Guohua Zeng et al. reported that the complications of patients in their RIRS groups were identical to those of the patients in their PCNL groups, but the complications were not the same as those observed by Yue Wu et al. and Yinghao Sun et al.[10, 11, 19, 20]. In surgery, PCNL still has a high risk of complications including massive hemorrhage, perforation, urine leakage, pleural injury, pleural effusion, intestinal injury and so on. Although the improvement in the PCNL era, which includes minimally invasive percutaneous nephrolithotomy, has considerably decreased the chance of bleeding, the solitary kidney with thick cortex, rich blood flow, abnormal blood vessels which is in the compensatory state for a long term is easily bleeds after puncture and expansion. But, it is reported PCNL has a better SFR without reoperation and the chance of infectious fever and sepsis after RIRS become larger than after PCNL. So it is also necessary to compare the intraoperative complications of PCNL and RIRS in patients with solitary kidney. In a word, for the patients who need to decide between RIRS and PCNL for solitary kidney calculi treatment, RIRS may not be a more safer way than PCNL. Of course, owing to the small number of articles included in this meta-analysis and the lack of RCTs, the accuracy of the conclusions of this article need further research to be verified.
There are a few limitations: (1) there were no randomized controlled trials, and the sample size was relatively small.(2) The basic characteristics of the included patients were not completely uniform. For example, the influencing factors (age, sex, etc.) were different, which may affect the results of the meta-analysis.(3) We cannot eliminate all sources of heterogeneity.(4) Publication and selection biases should also be considered to explain the results.