External validation of a nomogram for outcome prediction in management of medium-sized (1-2 cm) kidney stones.

BACKGROUND: Stone nomogram by Micali et al., able topredict treatment failure of shock-wave lithotripsy (SWL), retrograde intrarenal surgery (RIRS) and percutaneous nephrolithotomy (PNL) in the management of single 1-2 cm renal stones, was developed on 2605 patients and showed a high predictive accuracy, with an area under ROC curve of 0.793 at internal validation. The aim of the present study is to externally validate the model to assess whether it displayed a satisfactory predictive performance if applied to different populations. METHODS: External validation was retrospectively performed on 3025 patients who underwent an active stone treatment from December 2010 to June 2021 in 26 centers from four countries (Italy, USA, Spain, Argentina). Collected variables included: age, gender, previous renal surgery, preoperative urine culture, hydronephrosis, stone side, site, density, skin-to-stone distance. Treatment failure was the defined outcome (residual fragments >4 mm at three months CT-scan). RESULTS: Model discrimination in external validation datasets showed an area under ROC curve of 0.66 (95% 0.59-0.68) with adequate calibration. The retrospective fashion of the study and the lack of generalizability of the tool towards populations from Asia, Africa or Oceania represent limitations of the current analysis. CONCLUSIONS: According to the current findings, Micali's nomogram can be used for treatment prediction after SWL, RIRS and PNL; however, a lower discrimination performance than the one at internal validation should be acknowledged, reflecting geographical, temporal and domain limitation of external validation studies. Further prospective evaluation is required to refine and improve the nomogram findings and to validate its clinical value.

Dynamic changes of fetal head descent at term before the onset of labor correlate with labor outcome and can be improved by ultrasound visual feedback.

OBJECTIVE: The aim of the study was to evaluate the dynamic changes of angle of progression (AoP) before the onset of labor and their correlation with labor outcome and to investigate the effect of visual feedback using transperineal ultrasound on maternal pushing. METHODS: We recruited a group of low-risk nulliparous women with singleton pregnancy at term. We measured AoP at rest, during pelvic floor contraction and Valsalva maneuver (before and after visual feedback). We compared AoP between women who delivered vaginally (VD) and those who underwent a cesarean section (CS). We also assessed the correlation between AoP and labor durations. RESULTS: Overall, 222 women were included in the study; 129 (58.1%) had spontaneous VD, 35 (15.8%) had instrumental delivery, and 58 (26.1%) underwent CS. In comparison with rest, AoP decreased at PFMC (p < .001) and increased at first Valsalva (p < .001). AoP increased further significantly at Valsalva after visual feedback (p < .001). Women with VD had wider AoP at rest (p = .020), during Valsalva maneuver before (p = .024), and after visual feedback (p = .037). At cox regression analysis, wider AoP was associated with shorter first, second, and active second stages. CONCLUSION: Wider AoP at rest and under Valsalva is associated with vaginal delivery, the shorter interval to delivery, and shorter labor duration in nulliparous women at term. The accuracy of AoP in the prediction of cesarean delivery is modest and is unlikely to be clinically applicable in isolation for the prediction of the mode of delivery.

En-bloc resection of bladder tumors for pathological staging: the value of lateral margins analysis.

BACKGROUND: In endoscopic resection of colorectal tumors, the pathological assessment of the lateral margins is a strong predictor of tumor recurrence after resection. The aim of the current study is to evaluate the value of the peritumoral margins assessment in ERBT on tumor recurrence. METHODS: We retrospectively analyzed the data of 50 consecutive patients with NMIBC and treated by ERBT between January and December 2017. RESULTS: The lateral margins showed dysplasia in 16 patients and malignancy in three patients. Local recurrence occurred in 14 (28%) patients. It was noted that 57% of patients with recurrence showed some degree of dysplasia or malignancy in the lateral margin; however, on multivariate logistic regression lateral margins lesions were not significantly associated with recurrence (OR 2.175, 95% CI: 0.430-10.996, P=0.35). CONCLUSIONS: ERBT may improve the pathological report of bladder tumor. There was a trend toward increased rate of recurrence in patients with dysplasia or malignancy in their lateral margins; however, this was not statistically significant on multivariate analysis. Further studies with larger sample sizes are required to assess the value of lateral margin analysis.

Drug-Induced Urolithiasis in Pediatric Patients.

Drug-induced nephrolithiasis is a rare condition in children. The involved drugs may be divided into two different categories according to the mechanism involved in calculi formation. The first one includes poorly soluble drugs that favor the crystallization and calculi formation. The second category includes drugs that enhance calculi formation through their metabolic effects. The diagnosis of these specific calculi depends on a detailed medical history, associated comorbidities and the patient's history of drug consumption. There are several risk factors associated with drug-induced stones, such as high dose of consumed drugs and long duration of treatment. Moreover, there are some specific risk factors, including urinary pH and the amount of fluid consumed by children. There are limited data regarding pediatric lithogenic drugs, and hence, our aim was to perform a comprehensive review of the literature to summarize these drugs and identify the possible mechanisms involved in calculi formation and discuss the management and preventive measures for these calculi.