BackgroundLittle is known about the long-term prognosis of patients with IgA nephropathy (IgAN).MethodsThis retrospective cohort analysis evaluated clinical and histological findings at the time of renal biopsy, initial treatment, patient outcomes over 30 years, and risk factors associated with progression in 1,012 patients diagnosed with IgAN at our center since 1974.ResultsOf the 1,012 patients, 40.5% were male. Mean patient age was 33±12 years and mean blood pressure was 122±17/75±13 mmHg. Mean serum creatinine concentration was 0.89±0.42 mg/dL, and mean estimated glomerular filtration rate (eGFR) was 78.5±26.2 ml/min/1.73 m2. Mean proteinuria was 1.19±1.61 g/day, and mean urinary red blood cells were 36.6±35.3/high-powered field. Histologically, mesangial hypercellularity was present in 47.6% of patients, endothelial hypercellularity in 44.3%, segmental sclerosis in 74.6%, and tubular atrophy/interstitial fibrosis in 28.8% by Oxford classification. Initial treatment consisted of corticosteroids in 26.9% of patients, renin-angiotensin-aldosterone system inhibitor in 28.9%, and tonsillectomy plus steroids in 11.7%. The 10-, 20-, and 30-year renal survival rates were 84.3, 66.6, and 50.3%, respectively. Tonsillectomy plus steroids dramatically improved renal outcome. Cox multivariate regression analysis showed that higher proteinuria, lower eGFR, and higher uric acid at the time of renal biopsy were independent risk factors for the development of end stage renal disease (ESRD).ConclusionsIgAN is not a benign disease, with about 50% of patients progressing to ESRD within 30 years despite treatment.

In recent years, BK virus (BKV) nephritis after renal transplantation has become a severe problem. The exact mechanisms of BKV cell entry and subsequent intracellular trafficking remain unknown. Since human renal proximal tubular epithelial cells (HRPTEC) represent a main natural target of BKV nephritis, analysis of BKV infection of HRPTEC is necessary to obtain additional insights into BKV biology and to develop novel strategies for the treatment of BKV nephritis. We coincubated HRPTEC with BKV and the cholesteroldepleting agents methyl beta cyclodextrin (MBCD) and nystatin (Nys), drugs inhibiting caveolar endocytosis. The percentage of infected cells (detected by immunofluorescence) and the cellular levels of BKV large T antigen expression (detected by Western blot analysis) were significantly decreased in both MBCD-and Nys-treated HPRTEC compared to the level in HRPTEC incubated with BKV alone. HRPTEC infection by BKV was also tested after small interfering RNA (siRNA)-dependent depletion of either the caveolar structural protein caveolin-1 (Cav-1) or clathrin, the major structural protein of clathrin-coated pits. BKV infection was inhibited in HRPTEC transfected with Cav-1 siRNA but not in HRPTEC transfected with clathrin siRNA. The colocalization of labeled BKV particles with either Cav-1 or clathrin was investigated by using fluorescent microscopy and image cross-correlation spectroscopy. The rate of colocalization of BKV with Cav-1 peaked at 4 h after incubation. Colocalization with clathrin was insignificant at all time points. These results suggest that BKV entered into HRPTEC via caveolae, not clathrin-coated pits, and that BKV is maximally associated with caveolae at 4 h after infection, prior to relocation to a different intracellular compartment.

Our results revealed that rituximab therapy was associated with a reduction in the number of relapses and in the total dose of PSL needed. Therefore, rituximab appears to be a useful therapeutic agent for adult patients with steroid-dependent MCNS. These results suggest that this treatment is rational and should be considered as an important option in the management of adult patients with steroid-dependent MCNS.

Endothelial dysfunction is often found in both hyperuricemia and hemodialysis patients. Recent studies have shown that treating hyperuricemia with allopurinol improves endothelial dysfunction. This study is performed to assess the effect of febuxostat on endothelial dysfunction in hemodialysis patients with hyperuricemia. We randomly assigned 53 hemodialysis patients with hyperuricemia to a febuxostat (10 mg daily) group and a control group and measured flow-mediated dilation, serum uric acid (UA) levels, systolic and diastolic blood pressure, malondialdehyde-modified low-density lipoprotein (MDA-LDL), and highly sensitive C-reactive protein (hsCRP) at baseline and at the end of a 4-week study period. Flow-mediated dilation increased from 5.3% ± 2.4% to 8.9% ± 3.6% in the febuxostat group but did not change significantly in the control group. Treatment with febuxostat resulted in a significant decrease in serum UA level and a significant decrease in MDA-LDL compared with baseline, but no significant difference was observed in hsCRP level or blood pressure. No significant differences were observed in the control group. Febuxostat improved endothelial dysfunction and reduced serum UA levels and oxidative stress in hemodialysis patients with hyperuricemia.

Hyperuricemia is a frequent complication of chronic kidney disease (CKD). Febuxostat is a novel xanthine oxidase inhibitor that is metabolized by many metabolic pathways in the kidney and the liver. We performed a 1-year cohort study of 73 hyperuricemic patients who had an estimated glomerular filtration rate (eGFR) below 45 ml/min and were being treated with urate-lowering therapy. In 51 patients, treatment was changed from allopurinol to febuxostat, and the other 22 patients were continued on allopurinol. The serum levels of uric acid (UA) level, creatinine, and other biochemical parameters were measured at baseline and after 3, 6, 9, and 12 months of treatment. The serum UA levels significantly decreased from 6.1 ± 1.0 to 5.7 ± 1.2 mg/dl in the febuxostat group and significantly increased from 6.2 ± 1.1 to 6.6 ± 1.1 mg/dl in the allopurinol group. The eGFR decreased 27.3 to 25.7 ml/min in the febuxostat group and from 26.1 to 19.9 ml/min in the allopurinol group. The switch from allopurinol to febuxostat was significantly associated with the changes in eGFR according to a multiple regression analysis (β = −0.22145, P < 0.05). Febuxostat reduced the serum UA levels and slowed the progression of renal disease in our CKD cohort in comparison with allopurinol.