Impact of the adherence to medical treatment on the main urinary metabolic disorders in patients with kidney stones.

OBJECTIVE: To assess the effect of the adherence to medical treatment on urinary parameters in the 24-h metabolic study of patients with kidney stones. METHODS: A retrospective, longitudinal, descriptive, and observational study was carried out by reviewing the hospital electronic medical record from 2014 to 2018. The adherence to drug treatment was measured 6 months after its initiation, and the numerical values of the metabolic studies were compared. Wilcoxon tests were performed to compare the difference before and after treatment. RESULTS: Ninety patients were evaluated, with 73.3% of adherence. The 180-day overall adherence rate was 61.2% in patients treated with a single drug and 85.4% in patients treated with multiple drugs. There is a statistically significant increase in citrate levels in patients with good adherence in comparison with non-adherent patients (p=0.031 vs. p=0.528). CONCLUSIONS: Medical treatment and dietary measures in patients with kidney stones have an initial impact at 6 months on the values of the main urinary metabolic alterations that predispose to calculi formation; the most significant is seen in those patients with adherence to medical treatment for hypocitraturia.

Percutaneous Nephrolithotomy in Horseshoe Kidneys: Results of a Multicentric Study.

Objective: To report the outcomes of percutaneous nephrolithotomy (PCNL) in horseshoe kidneys (HSK) in 12 institutions worldwide and evaluate the impact of patient position during operation. Methods: We carried out a retrospective analysis of PCNL procedures performed between 2008 and 2018 in patients with HSK. Pre-, peri-, and postoperative data were collected, and a subgroup analysis was performed according to patient position. Success was defined as an absence of >4-mm fragments. Values of p < 0.05 were considered significant. Results: We analyzed 106 procedures. The transfusion, complication, and immediate success rates (ISRs) were 3.8%, 17.5%, and 54.7%, respectively. The final success rate (FSR) increased to 72.4% after a mean of 0.24 secondary procedures. Logistic regression showed that higher body mass index (BMI) and stone size were significantly associated with residual fragments ≥4 mm. Sixty-seven patients (63.2%) were treated in prone and 39 (36.8%) in supine position. The prone group had a significantly higher BMI than the supine group (30.1 vs 27.7, p = 0.024). The transfusion, complication, and ISRs between the prone and supine groups were 4.5% vs 2.6% (p = 0.99), 16.9% vs 18.4% (p = 0.99), and 52.5% vs 69.2% (p = 0.151), respectively. Surgical time was significantly longer in the prone group (126.5 vs 100 minutes, p = 0.04). Upper pole was the preferred access in 80.3% of the prone group and 43.6% of the supine group (p < 0.001). The prone group had significantly more Clavien 2 complications than the supine (p = 0.013). The FSR in the prone and supine groups increased to 66.1% and 82.1% after 0.26 and 0.21 secondary procedures, respectively. No complications higher than Clavien 3 occurred. Conclusion: PCNL in patients with HSK is safe and effective with a low complication rate. Higher BMI and stone size negatively impacted outcomes. Supine PCNL may be an option for treating kidney stones in patients with HSK.

Impact of Obesity on Outcomes of Supine Percutaneous Nephrolithotomy.

Objectives: To determine whether obesity has an impact on the outcomes of supine percutaneous nephrolithotomy (PCNL). Patients and Methods: We retrospectively evaluated a prospectively created database of patients who underwent PCNL in the supine position from June 2009 to June 2014. The patients were divided into two groups according to their body mass index (BMI): <30 kg/m2 (group 1, nonobese) and ≥30 kg/m2 (group 2, obese). Pre, peri, and postoperative data were analyzed. Stone complexity was classified according to Guy's stone score. The primary endpoint was the absence of stone fragments of ≥4 mm on CT scans at postoperative day 1. Complications were graded according to the modified Clavien classification. Results: Of the 401 patients, 307 (76.6%) were nonobese and 94 (23.4%) were obese. Regarding demographic and stone characteristics, group 2 (BMI ≥30 kg/m2) had a higher percentage of female patients (67.3% vs 50.4%, p = 0.002) and a higher mean BMI (34.8 vs 24.5 kg/m2, p < 0.001) than group 1. Success rates were not statistically different between the groups (group 1 = 61.8%, group 2 = 51%, p = 0.08). There were no differences in the transfusion rate (group 1 = 2.9%, group 2 = 4.2%, p = NS) or total number of complications greater than Clavien grade 1 (group 1 = 13.6%, group 2 = 13.8%, p = NS). Conclusion: In a retrospective study of 400 patients undergoing PCNL, the outcomes were not different between nonobese and obese patients. To our knowledge, this is the first study evaluating these outcomes for PCNL performed in the supine position. Further multicenter and prospective studies are necessary to verify these findings.

Repeat knot formation in a patient with an indwelling ureteral stent.

A patient treated for nephrolithiasis formed knots in 2 occasions, in 2 separate indwelling ureteral stents. This rare complication may make stent removal difficult. To our knowledge, this is the first case report of repeat knot formation in a single patient.

Repeat knot formation in a patient with an indwelling ureteral stent

A patient treated for nephrolithiasis formed knots in 2 occasions, in 2 separate indwelling ureteral stents. This rare complication may make stent removal difficult. To our knowledge, this is the first case report of repeat knot formation in a single patient.