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Background: Oxidative stress is prevalent in dialysis patients and has been implicated in the pathogenesis of cardiovascular disease and anemia. Vitamin E is a fat-soluble antioxidant that plays a central role in reducing lipid peroxidation and inhibiting the generation of reactive oxygen species. The aim of this cross-over randomized study was to compare the effects of a vitamin E-coated polysulfone (Vit E PS) membrane and a non-vitamin E-coated polysulfone (PS) membrane on inflammatory markers and resistance to erythropoietin-stimulating agents (ESAs). Methods: After a 1-month run-in period of standard bicarbonate dialysis with a synthetic membrane, 62 patients of both genders, and older than 18 years, dialysis vintage 48 ± 27 months, BMI 22 ± 3 (from 13 different dialysis units) were randomized (A-B or B-A) in a cross-over design to Vit E PS (treatment A) and to PS (treatment B) both for 6 months. C-reactive protein (CRP) and interleukin-6 (IL-6) concentrations were determined by a sandwich enzyme immunoassay at baseline and every 2 months; red blood cell count, ESA dose and ESA resistance index (ERI) were assessed monthly. Results: Hemoglobin (Hb) levels significantly increased in the Vit E PS group from 11.1 ± 0.6 g/dl at baseline to 11.5 ± 0.7 at 6 months (p < 0.001) and remained unchanged in the PS group. Although ESA dosage remained stable during the observation periods in both groups, ERI was significantly reduced in the Vit E PS group from 10.3 ± 2.2 IU-dl/kg/g Hb week at baseline to 9.2 ± 1.7 at 6 months (p < 0.001). No significant variation of ERI was observed in the PS group. A significant reduction in plasma CRP and IL-6 levels was observed in the Vit E PS group: CRP from 6.7 ± 4.8 to 4.8 ± 2.2 mg/l (p < 0.001) and IL-6 from 12.1 ± 1.4 to 7.5 ± 0.4 pg/ml (p < 0.05). In the PS group, CRP varied from 6.2 ± 4.0 to 6.4 ± 3.7, and IL-6 from 10.6 ± 2.1 to 9.6 ± 3.5 (p = n.s.). Conclusions: Treatment with Vit E PS membranes seems to lead to a reduction in ESA dosage in HD patients; in addition, a low chronic inflammatory response may contribute to a sparing effect on exogenous ESA requirements.

Nine patients with mixed cryoglobulinemia and severe membranoproliferative glomerulonephritis were treated with plasma exchange alone or in combination with medium to low amounts of corticosteroids, but never with cytotoxic drugs. In 5 patients renal function and/or proteinuria improved after plasma exchange, and no clinical relapse usually occurred when the procedures were reduced or discontinued. These procedures seemed of particular effect in the presence of histologically active and not irreversible lesions and rapid deterioration of renal function. While cryocrit almost invariably decreased, circulating immune complex or complement levels were unpredictably affected by plasma exchange. Cryocrit, but not immune complex or complement levels, was the serological parameter which most often closely correlated with signs of renal involvement (i.e., proteinuria and/or serum creatinine). Thus, plasma exchange might be a safe and useful tool in the treatment of an often drug-resistant and rapidly progressive renal involvement occurring in patients with mixed cryoglobulinemia.

The occurrence of nephritis is considered to be the most important factor influencing the prognosis in systemic lupus erythematosus (SLE). Despite the apparent histological similarity of the lesions, however, patients with diffuse proliferative glomerulonephritis (DPGN) may exhibit different outcomes. A retrospective study was carried out on 81 SLE patients with DPGN to evaluate the prognostic significance of different clinical, serological and histological variables; in particular, 95 renal biopsies were re-evaluated and the activity and chronicity indices for the patients were determined. A positive correlation was observed between the presence of chronic lesions on renal biopsy and a poor renal outcome (< 0.001). Moreover, in the repeat biopsies the patients with a poor outcome showed a higher degree of chronic lesions. Active lesions and other clinical and serological parameters did not correlate with the outcome.

A striking association between hepatitis C virus (HCV) and mixed cryoglobulinemia (MC) has been reported by various authors, regardless of the presence of chronic hepatitis. The aim of this study is to evaluate the prevalence of HCV-related markers in cryoglobulinemic membranoproliferative glomerulonephritis (MPGN) which is one of the most severe complications of MC. Antibodies against HCV have been detected by second-generation Chiron ELISA and RIBA in 26/26 (100%) cryoglobulinemic MPGN. In addition, serum HCV RNA, expression of the ongoing viral replication, was present in 7/7 patients by the polymerase chain reaction technique. The high percentage of anti-HCV seropositivity suggests that this virus may play an important role in the pathogenesis of this immunemediated glomerulonephritis.