The use of urodynamic to assess the mechanism of incontinence in patients with Yang-Monti based catheterizable cutaneous stomas.

OBJECTIVE: To analyze the static and dynamic urodynamic parameters of reservoirs and continent conduits in continent cutaneous urinary diversion with catheterizable stoma. MATERIALS AND METHODS: 76 patients had augmented ileocystoplasty or continent urinary diversion with catheterizable urinary stoma based on Mitrofanoff principle and Yang-Monti procedure using subserous tunnel as continence mechanism. They were followed up for at least 6 months post-operatively for continence through stoma and divided into two groups (continents vs non-continent) according to stomal continence. Both groups had urodynamic assessment performed via the stoma to assess reservoir capacity, pressure and contractions, efferent limb functional length, reservoir overactivity, static and dynamic maximal closure pressures and leak point pressure. RESULTS: Continence rate was 87%. Continent group included 66 patients and incontinent group included 10 patients. In both groups at rest, the reservoir pressure after filling did not exceed 25 cm H2O. During peristaltic contraction, the pressure did not exceed 30 cm H2O and the duct remained continent. After Valsalva maneuver, the reservoir pressure increased up to 34 (+ 7.4) cm H2O and leakage occur in 10 patients (13%). Reservoir (wall) overactivity was recorded in 54 patients, with insignificant rise in intraluminal pressure during the contractions. In both groups, the efferent tract closing pressure was always higher than the reservoir pressure. The mean of maximal closing pressure at Valsalva was 82.5 (+ 4.18) cm H2O in the continent group and 61.66 (+ 8.16) cm H2O in the incontinent group. The mean functional length of the conduit was 4.95 + 1.62 in the continent group and 2.80 + 1.50 cm in the incontinent group. CONCLUSIONS: Urodynamic evaluation of continent catheterizable cutaneous stoma after Yang-Monti procedure has a practical significance. Functional length of the conduit seems to be the most influential factor for continence reflecting static & dynamic maximal closure pressure. Higher conduit closing pressure is associated with better continence. Contractions of the pouch and peristaltic contraction of the conduit has no effect on continence mechanism.

RETRACTION: Effect of preoperative ureteral stenting on the surgical outcomes of patients with 1-2 cm renal stones managed by retrograde intrarenal surgery using a ureteral access sheath.

This retracts the article "Effect of preoperative ureteral stenting on the surgical outcomes of patients with 1-2 cm renal stones managed by retrograde intrarenal surgery using a ureteral access sheath"  (https://doi.org/10.4081/aiua.2023.12102) published on December 28, 2023.

Relation between myostatin levels and malnutrition and muscle wasting in hemodialysis patients.

BACKGROUND AND AIM: Malnutrition is one of the most troublesome comorbidities among hemodialysis patients (HD). Myostatin (MSTN) belongs to the transforming growth factor-ß superfamily. In HD patients, MSTN effects are not limited to skeletal muscle growth. The present study aimed to assess MSTN levels in HD patients and its relation to various clinical and biochemical parameters. PATIENTS AND METHODS: The present case control study included 60 patients on HD for at least three years. In addition, there were age and sex-matched healthy subjects who constitutes the control group. Nutritional status was evaluated using the malnutrition inflammation score (MIS). Muscle wasting in the present study was evaluated using the lean tissue index (LTI) as assessed by the body composition monitor (BCM). Rectus Femoris Muscle (RFM) thickness was also measured as indicator for nutritional status of patient. RESULTS: The present study included 60 HD patients, and ageand sex-matched healthy controls. Patients expressed significantly higher myostatin levels when compared to controls [median (IQR): 221.3 (153.5-688.2) versus 144.8 (97.0-281.7), p < 0.001]. According to MIS, patients were classified into those with no/mild malnutrition (n = 22) and others with moderate/severe malnutrition (n = 38). Comparison between the two subgroups revealed that the former group had significantly lower myostatin levels [167.7 (150.3-236.3) versus 341.7 (160.9-955.9), p = 0.004]. According to LTI, patients were classified into those with muscle wasting (n = 23) and others without muscle wasting (n = 37). Comparative analysis showed that patients in the former group had significantly higher myostatin levels [775.1 (325.1-2133.7) versus 161.8 (142.6-302.3), p < 0.001]. CONCLUSIONS: Myostatin seems to be a promising marker for identification of malnutrition and muscle wasting in HD patients.

The outcome of ultrasound-guided insertion of central hemodialysis catheter.

OBJECTIVE: To point out our experience and assess the efficacy and safety of real-time ultrasound-guided central internal jugular vein (IJV) catheterization in the treatment of hemodialysis patients. METHODS: This retrospective study comprised 150 patients with end-stage renal disease (ESRD) who had real-time ultrasonography (US)-guided IJV HD catheters placed in our hospital between March 2019 and March 2021. Patients were examined for their demographic data, etiology, site of catheter insertion, type (acute or chronic) of renal failure, technical success, operative time, number of needle punctures, and procedure-related complications. Patients who have had multiple catheter insertions, prior catheterization challenges, poor compliance, obesity, bony deformity, and coagulation disorders were considered at high-operative risk. RESULTS: All patients experienced technical success. In terms of patient clinical features, an insignificant difference was observed between the normal and high-risk groups (p-value > 0.05). Of the 150 catheters, 62 (41.3%) were placed in high-risk patients. The first-attempt success rate was 89.8% for the normal group and 72.5% for the high-risk group (p = 0.006). IJV cannulation took less time in the normal-risk group compared to the highrisk group (21.2 ± 0.09) minutes vs (35.4 ± 0.11) minutes, (p < 0.001). There were no serious complications. During the placing of the catheter in the internal jugular vein, four patients (6.4%) experienced arterial puncture in the high-risk group. Two participants in each group got a small neck hematoma. One patient developed a pneumothorax in the high-risk group, which was managed with an intercostal chest tube insertion. CONCLUSIONS: Even in the high-risk group, the real-time US-guided placement of a central catheter into the IJV is associated with a low complication rate and a high success rate. Even under US guidance, experience lowers complication rates. Real-time USguided is recommended to be used routinely during central venous catheter insertion.

Effect of preoperative ureteral stenting on the surgical outcomes of patients with 1-2 cm renal stones managed by retrograde intrarenal surgery using a ureteral access sheath.

OBJECTIVE: To assess the surgical results of patients who underwent retrograde intrarenal surgery (RIRS) using a ureteral access sheath (UAS) for management of renal stones sized 1-2 cm compared between patients who did and did not undergo preoperative ureteral stenting. MATERIALS AND METHODS: This prospective study included 83 patients (aged ≥ 20 years) who underwent RIRS from July 2021 to January 2023. All patients had renal calculi (stone size: 1-2 cm) located within the pelvicalyceal system. 43 and 40 patients were allocated to the non-prestent (group A) and prestent (group B), respectively. Patient baseline characteristics, renal stone details, operative data, stone-free rate (SFR) at 4 weeks and 6 months, and perioperative complications were compared between groups. RESULTS: The baseline characteristics of all patients were comparable across the groups. Four weeks after surgery, the overall stone-free rate (SFR) stood at 62.65%. In the non-prestent and prestent groups, the SFRs were 58.12% and 67.5%, respectively (p = 0.89). By the sixth month post-surgery, the overall SFR rose to 80.72%. In the non-prestent and prestent groups, the SFRs were 76.74% and 85%, respectively (p = 0.081). No notable differences emerged in other variables, including perioperative complications, between the two groups. CONCLUSIONS: The SFR showed no significant difference between the prestenting and non-prestenting groups at the 4-week and 6-month postoperative marks. Additionally, there were no substantial differences in complications during surgery and recovery between the groups. Notably, the SFR increased from 4 weeks to 6 months without any additional procedures in either group.