Ureteroenteric strictures after cystectomy: Side-specific risk factors and radiological assessment.

Objective: To evaluate risk factors contributing to side-specific benign ureteroenteric strictures following radical cystectomy with an ileal conduit. Materials and Methods: Data obtained from patients with bladder cancer who underwent radical cystectomy with ileal conduit surgery between 2015 and 2018 were retrospectively analysed. Imaging prior to surgery was analysed, regarding calcifications in the aorta, sarcopenia and postoperatively for length of remaining left ureter. Descriptive analyses were performed on preoperative and perioperative data, comparing patients who developed unilateral left- or right-sided strictures, bilateral strictures, to those who remained free of strictures. COX regression analysis was employed to calculate crude and adjusted hazard ratio for side-specific strictures. Results: The study included 395 patients. Strictures developed in 19% (75/395) of the patients, within a median period of 9 months: 57% (43/75) unilateral left sided, 20% (15/75) unilateral right sided and 23% (17/75) bilateral. Unilateral left-sided stricture was associated with higher body mass index (p = 0.077) and hypercholesterolemia (p = 0.007). Right-sided stricture was associated with a history of prior abdominal surgery (p = 0.029) and postoperative leakage (p = 0.004). Bilateral stricture was associated with smoking (p = 0.006) and high BMI (p = 0.015). The adjusted HR comparing patients with and without previous abdominal surgery was only significantly higher for right-sided ureteroenteric strictures (HR 3.18 [95% CI: 1.11; 9.05]) compared with patients without strictures. No association was identified between strictures and preoperative aortic calcification of the abdominal aorta or sarcopenia as estimated from imaging. Conclusion: The aetiology of ureteroenteric strictures appears multifactorial. Our findings suggest that development of left-sided stricture is influenced by factors associated with metabolic syndrome, indicating a potential role of distal ureteric ischemia. On the other hand, right-sided stricture was more frequent in patients with previous abdominal surgery and postoperative leakage.

Prediction of Renal Function in Living Kidney Donors and Recipients of Living Donor Kidneys Using Quantitative Histology.

BACKGROUND: Living kidney donors (LKDs) are at increased risk of chronic kidney disease, whereas transplant recipients experience progressive reduction of graft function. We examined the predictive value of quantitative stereology on renal function in LKDs and recipients of living donor kidneys, based on perioperative biopsies from the donated kidney. METHODS: Cortex volume of both donor kidneys was determined by contrast-enhanced computed tomography and single-kidney glomerular filtration rate (GFR) by 51 chrome-EDTA clearance together with renography. Glomerular density was used to estimate total glomeruli number in addition to glomerular volume, glomerular sclerosis, kidney fibrosis, and arteriole dimensions. GFR measurements were repeated 1 y after transplantation in both LKDs and recipients. Associations between GFR at follow-up and cortex volume and histomorphometric parameters after adjustment of age, gender, body mass index, smoking status, 24-h blood pressure, and single-kidney GFR were examined. RESULTS: We included 49 LKDs (age, 51 ± 12 y) and 51 recipients (age, 44 ± 13 y). At follow-up, GFR was 71 ± 16 mL/min in LKDs and 61 ± 18 mL/min in recipients with hyperfiltration being more prominent in LKDs (30.4%) as compared to recipients (16.4%; P < 0.05). One-year GFR in donors correlated to cortex volume ( P < 0.001) but not to any histological parameters, whereas GFR in recipients correlated to the amount of interstitial fibrosis ( P < 0.01) but not to other histological parameters or cortex volume. CONCLUSIONS: Kidney cortex volume, but not renal histology parameters, predicts 1-y renal outcome in LKDs. In contrast, the amount of interstitial fibrosis, but not cortex volume, predicts 1-y graft function in recipients.

Kidney structural characteristics based on a kidney biopsy and contrast-enhanced computed tomography in healthy living kidney donors.

The demands for kidney transplantations are increasing, and so is the number of live kidney donors (LKDs). Recent studies show that LKDs have an increased risk of developing end-stage renal disease compared with healthy non-donors. However, the knowledge about factors predicting renal disease in kidney donors is sparse. Some evidence points to increased glomerular sclerosis and kidney fibrosis, as well as a low number of glomeruli as associated with a worse renal outcome. This methodological study investigated that which estimates are obtainable with a standard kidney biopsy taken from the donated kidney during the transplantation, and a standard contrast-enhanced computed tomography (CT) in kidney donors. CT-scans were used to obtain total volume of the kidney and kidney cortex using the Cavalieri estimator and 2D-nucleator. Glomerular number density in the biopsies was estimated by a model-based method, and was multiplied by total cortex volume in order to estimate the total number of glomeruli in the kidney. Glomerular volume was estimated by the 2D-nucleator and a model-based stereological technique. Kidney fibrosis (point-counting), glomerular sclerosis (evaluation of glomerular profiles), and arteriole dimensions (2D-nucleator) were also estimated in the biopsy sections from the donated kidney. Various studies have attempted to identify predictors of renal outcome in LKDs. There is no consensus yet, and further studies are needed to elucidate if and how the estimates described in this study are associated with renal outcome in LKDs.