Is multiple tract percutaneous nephrolithotomy a safe approach for staghorn calculi?

Antegrade flexible ureteroscopy-assisted percutaneous nephrolithotomy for staghorn calculi: a prospective randomized controlled study

The aim is to compare the efficacy and safety between single percutaneous nephrolithotomy (sPNL) and antegrade flexible ureteroscopy-assisted percutaneous nephrolithotomy (aPNL) for the treatment of staghorn calculi. A prospective randomized controlled study was conducted at the Second Hospital of Tianjin Medical University. A total of 160 eligible patients were included, with 81 in the sPNL group and 79 in the aPNL group. The study first compared the overall differences between sPNL and aPNL. Then, the patients were divided into two subgroups: Group 1 (with less than 5 stone branches) and Group 2 (with 5 or more stone branches), and the differences between the two subgroups were further analyzed. The results showed that aPNL had a higher stone-free rate (SFR) and required fewer percutaneous tracts, with a shorter operation time compared to sPNL (P < 0.05). Moreover, aPNL significantly reduced the need for staged surgery, particularly in patients with 5 or more stone branches. Moreover, there were no significant differences in the changes of hemoglobin levels and the need for blood transfusions between the sPNL and aPNL groups, and the incidence of multiple tracts was lower in the aPNL group. The two groups showed comparable rates of perioperative complications. We concluded that aPNL resulted in a higher SFR for staghorn calculi, and required fewer multiple percutaneous tracts, reduced the need for staged surgery, and had a shorter operative time than PNL alone, especially for patients with 5 or more stone branches. Furthermore, aPNL did not increase the incidence of surgical complications.

Initial Experience of Simultaneous Combined use of Percutaneous Nephrolithotomy and Flexible Ureteroscopy in Complex Renal Calculi: A Novel Surgical Technique of 'Through-Through' Approach

BACKGROUND

For complex branched renal calculi, the endoscopic combined intrarenal surgery (ECIRS) is worldwide prevalent. This study aimed to present a novel surgical technique of percutaneous nephrolithotomy combined with antegrade flexible ureteroscopy which is named 'Through-through' approach.

METHODS

We retrospectively analyzed the data of 68 patients with complex renal calculi who underwent combined PNL and flexible ureteroscopy surgery using 'Through-through' approach at our center between August 2019 and December 2021. The 'Through-through' approach to surgery was indicated in residual calyceal calculi that neither rigid nephroscope nor retrograde flexible ureteroscope could reach. The brief procedure of this technique involved determining the direction of targeted calyces with the nephroscope first, followed by putting flexible ureteroscope into the targeted calyx through the nephroscope instrument channel and basketing or dusting residual calculi through the flexible ureteroscope instrument channel.

RESULTS

The mean maximum stone diameter was 4.0 ± 0.4 cm. The mean operative duration was 100.1 ± 18.0 minutes, and mean hemoglobin loss was 21.4 ± 5.1 g/L. In all 68 patients, calculi were cleared in 62 patients, and the stone free rate was 91.2%. Five patients underwent further surgery after 2 weeks because of significant residual calculi. One patient that had a 6 mm residual stone chose observational follow-up. Ten patients emerged with postoperative fever but did not progress to uroseptic shock. There were no Clavien grade ≥ III complications, and none of the patients required blood transfusion.

CONCLUSION

The 'Through-through' approach is safe, feasible and effective for complex renal calculi patients. It is a complementary solution to the failed endoscopic combined intrarenal surgery.

One-stage efficacy of single tract minimally invasive ECIRS in the improved prone frog split-leg position for staghorn stones

OBJECTIVE

To explore the feasibility, safety, and effectiveness of single tract minimally invasive endoscopic combined intrarenal surgery (stmECIRS) in the improved prone frog split-leg position for staghorn stones.

METHOD

A total of 83 patients with staghorn stones were retrospectively reviewed between January 2018 and June 2021. According to surgical procedure and position, patients were divided into a group of single tract minimally invasive percutaneous nephroscopy (stmPNL) in the prone position and a group of stmECIRS in the improved prone frog split-leg position (turned to the prone position after preset the flexible ureteroscope sheath in lithotomy position, meanwhile, bend both hips and knees to be frog abduction). Demographic characteristics, laboratory tests, stone characters, surgical information, stone-free rate (SFR), and perioperative complications were observed and analyzed.

RESULTS

There were no significant differences in demographic characteristics, changes level of Scr and Hb, stone size, radiation density, length of hospital stay, and operation time between the two groups. One-stage SFR in the stmECIRS group was significantly higher than that in the stmPNL group (84.4% vs. 57.9%) (P = 0.007), only 2 patients required blood transfusion after surgery (P = 0.862), and other postoperative complications were not statistically significant (P = 0.345).

CONCLUSIONS

StmECIRS in improved prone frog split-leg position has a higher one-stage SFR than stmPNL for staghorn renal stones, and without complications increased, which is a safe, efficient and feasible treatment.

Identification of key genes in benign prostatic hyperplasia using bioinformatics analysis

PURPOSE

This study aimed to identify differentially expressed genes (DEGs) and pathways in benign prostatic hyperplasia (BPH) by comprehensive bioinformatics analysis.

METHODS

Data of the gene expression microarray (GSE6099) were downloaded from GEO database. DEGs were obtained by GEO2R. Functional and enrichment analyses of selected genes were performed using DAVID database. Protein-protein interaction network was constructed through STRING. Anterior gradient 2 (ARG2) and lumican (LUM) staining in paraffin-embedded specimens from BPH and normal prostate (NP) were detected by immunohistochemistry (IHC). Differences between groups were analyzed by the Student's t test.

RESULTS

A total of 24 epithelial DEGs and 39 stromal DEGs were determined. The GO analysis results showed that epithelial DEGs between BPH and NP were enriched in biological processes of glucose metabolic process, glucose homeostasis and negative regulation of Rho protein signal transduction. For DEGs in stroma, enriched biological processes included response to ischemia, antigen processing and presentation, cartilage development, T cell costimulation and energy reserve metabolic process. ARG2, as one of the epithelial DEGs, was mainly located in epithelial cells of prostate. In addition, LUM is primarily expressed in the stroma. We further confirmed that compared with NP, the BPH have the lower ARG2 protein level (p = 0.029) and higher LUM protein level (p = 0.003) using IHC.

CONCLUSIONS

Our study indicated that there are possible differentially expressed genes in epithelial and stromal cells, such as ARG2 and LUM, which may provide a novel insight for the pathogenesis of BPH.

Experimental autoimmune prostatitis: different antigens induction and antigen-specific therapy

PURPOSE

Chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) has uncertain etiology and lacks effective treatment. Autoimmunity is an important pathogeny, and experimental autoimmune prostatitis (EAP) models have long been used for studying CP/CPPS. This review presents the detailed current knowledge of EAP models based on evaluation criteria aspects to provide a tool for model selection in pathogenesis studies and therapeutic drug screening.

METHODS

We extensively searched the published literature on CP/CPPS and different antigen-induced EAP models focusing on the histopathology, clinical-related phenotypes, and biochemical indicators. We also cover the changes in the prostate function and other organs in EAP. Finally, we try to get some insights about antigen-based therapeutic approaches for CP/CPPS.

RESULTS

Several inciting autoantigens were reported in EAP, including male accessory gland extracts, prostate extracts (PE), prostatic steroid-binding protein, prostatic spermine-binding protein (p25), prostatic acid phosphatase, seminal vesicle secretory protein 2, and T2 peptide. All of these models mimicked histological prostatitis, however only p25- and T2-induced models developed both pelvic pain and voiding behaviors. PE immunization is the most widely used method. Diminished fertility and mental health disorders can be found in PE model. Oral and intravenous T2 peptide have been studied for antigen-specific therapy and achieved preliminary progress in EAP models.

CONCLUSIONS

PE-induced model is the most commonly used, while T2- or p25-model could serve as a promising CP/CPPS model. Antigen-specific therapy in CP/CPPS deserves further study.