Vitamin E-bonded cellulose membrane, lipoperoxidation, and anemia in hemodialysis patients

In hemodialysis patients, oxidative stress results from an imbalance between the production of reactive oxygen species and antioxidant defense mechanisms. Recently, a new dialysis multi-layer membrane has been developed, by modifying the inner surface of regenerated cellulose to support a vitamin E coating. The aim of our study was to investigate the effects of hemodialysis treatment with vitamin E-modified membrane on anemia and erythropoietin requirement in a group of chronic uremic patients. Ten uremic, non diabetic, patients on standard bicarbonate dialysis were treated with vitamin E-bonded dialysis membrane for 12 months. Hematological parameters, erythropoietin requirement, serum vitamin E and serum malonyldialdehyde (MDA) were evaluated before starting the study and monthly. No significant changes in hemoglobin level, RBC count, hematocrit and EPO requirement were observed. Basal vitamin E levels were in the normal range (13.0 +/- 2.88 mg/L vs. 14.79 +/- 3.12 mg/L; NS). On the contrary, basal MDA levels were higher than those observed in the control group (1.87 +/- 0.36 vs. 1.13 +/- 0.18 mmol/mL; p < 0.01) and a significant decrease of MDA levels was found after 1 month of Excebrane treatment (1.39 +/- 0.25 nmol/mL; p < 0.02). In conclusion, the role of the "oxidative hemolysis" in the pathogenesis of anemia in CHD patients is still not clearly defined, but it could be of minor clinical relevance. Although the effectiveness of vitamin E-coated membranes as a scavenger of ROS allows a better control of intradialytic oxidative stress, it doesn't seem to contribute to clinical management of anemia in these patients.

IgA nephropathy: multivariate statistical analysis aimed at predicting outcome

BACKGROUND

Several risk factors of IgA nephropathy (IgAN) have been identified, but their importance in predicting outcome is still controversial.

METHODS

We conducted a retrospective study on 119 patients (pts) with IgAN. All had a follow-up of over five years (mean 134+/-56 months). For each patient we recorded age, 24h proteinuria, hematuria, renal function (RF), arterial hypertension (AH) and histological features. Multivariate analysis was done for predictive purposes (segmentation, using Chi-squared Automatic Interaction Detection-CHAID).

RESULTS

AH at the time of renal biopsy was the principal and independent predicting factor: 30/50 (60%) hypertensive pts had serum creatinine > or =1.5 mg/dL at the end of follow-up compared to 9/69 (13%) pts with normal blood pressure. Age was a further predictive parameter: 21/28 (75%) pts with AH and age over 39 years had reduced RF at the last examination. In this subgroup, 18/19 (95%) with evidence of tubulo-interstitial lesions showed a decline of RF.

CONCLUSIONS

AH and age alone are significant prognostic factors; tubulo-interstitial lesions are an additional pointer to poor outcome in these pts. The algorithm obtained with segmentation analysis may be a guideline for prognosis in single patients with IgA nephropathy.