No abstract

Peritoneal morphological changes seem to be related to dialysis solutions bioincompatibility and to infections, but the uremic milieu per se may also contribute to peritoneal changes. The influence of diabetes and diabetes-associated comorbidities on peritoneal histological changes in the pre-dialysis stage have been insufficiently studied. The aim of this study is to analyze the effect of diabetes and serum albumin levels on peritoneal histology and certain clinical variables such as peritoneal permeability, technique failure, and general mortality in patients starting peritoneal dialysis (PD) treatment. Eighteen PD patients without diabetes (uremic non-diabetic group, U-ND) and 65 with diabetes (uremic diabetic group, U-D) were studied prospectively. Clinical and biochemical variables were registered, and a parietal peritoneum biopsy was obtained at the time of the peritoneal catheter placement. Peritoneal histology was evaluated by light microscopy and immunohistochemistry. A control group of 15 non-uremic, non-diabetic (NU-ND) patients who underwent non-complicated elective abdominal surgery was also studied and used as control. The proportion of patients with peritoneal morphological changes as evaluated by light microscopy was higher in the two groups of uremic patients than in the control. The U-D group had higher mesothelial loss (40.9 vs 29.4%), higher mesothelial basement membrane thickening (45.5 vs 23.5%), higher proportion of vascular wall thickening/sclerosis (39.7 vs 11.1%), and higher proportion of inflammatory infiltrate (45.4 vs 23.6%) than the U-ND group. Uremic patients had lower density of mesothelial cells and higher density of inflammatory cells than the control, as evaluated by immunohistochemistry. These changes were even more striking in the U-D group than in the U-ND group. On the other hand, inflammatory infiltration to the peritoneum, mesothelial cell loss, and mesothelial basement membrane thickening were associated with higher technique failure and mortality. However, when the serum albumin level was introduced into the model, the aforementioned associations became nonsignificant. In conclusion, uremia and diabetes were associated with important peritoneal histological changes before starting PD treatment. Diabetes associated with uremia was more strongly related to the peritoneal changes than uremia per se. Hypoalbuminemia and peritoneal inflammatory infiltrate were markedly associated with technique failure and mortality in patients starting PD treatment.

Background: Arterial calcification (AC) is frequent in patients with end stage renal disease and is also considered a risk factor for later morbidity and mortality. However, long-term factors associated with the process are not well known. We analyzed the trends over time of biomarkers related with development and progression of AC in incident patients on peritoneal dialysis (PD). Methods: We performed a prospective study with 186 patients on PD followed up for 1 year. We analyzed the progression of AC in the abdominal aorta and pelvic vessels by calcification score (CaSc), using16-cut computerized multidetector tomography at baseline and 1 year. Variables related with PD treatment, inflammation, and mineral metabolism were measured at baseline, 6, and 12 months of follow-up. Changes in biochemical variables were analyzed for their relationship with changes in AC. Results: Over 1 year, the number of patients with AC increased from 47 to 56%, and CaSc from 355 (interquartile range [IQR] 75-792) to 529 (IQR 185-1632). A total of 43.5% of patients remained free of calcification, 11.7% had new calcifications, and 44.8% had progression of calcification. Older age, diabetes, high systolic blood pressure, body mass index, cholesterol, and osteoprotegerin (OPG), as well as lower levels of albumin, serum creatinine, and osteocalcin, were associated with development of new, and rapid progression of, calcification. In multivariate logistic analysis, OPG remained the most significant (OR 1.27, 95% CI 1.11-1.47, p < 0.001). Conclusion: OPG was the strongest risk factor associated with new development and rapidprogression of AC in incident PD patients.