Comparison of methylprednisolone plus prednisolone with prednisolone alone as initial treatment in adult-onset minimal change disease: a retrospective cohort study.

BACKGROUND AND OBJECTIVES: Previous studies suggested that intravenous methylprednisolone possibly accelerates remission of proteinuria in adult-onset minimal change disease; its impact on relapse of proteinuria is unknown. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This multicenter retrospective cohort study included 125 adult-onset minimal change disease patients diagnosed by kidney biopsy between 2000 and 2009 and treated initially with corticosteroid in five nephrology centers in Japan participating in the Study of Outcomes and Practice Patterns of Minimal Change Disease. Times to first remission and first relapse of proteinuria after initiating the first immunosuppressive therapy were compared between 65 patients with initial use of intravenous methylprednisolone followed by prednisolone and 60 patients with initial use of prednisolone alone using multivariate Cox proportional hazards models. After calculating the probability of receiving methylprednisolone and prednisolone using a logistic regression model (propensity score), the results were ascertained using propensity score-matched and -stratified models. RESULTS: During the median 3.6 years of observation (interquartile range=2.0-6.9), all 65 patients in the methylprednisolone and prednisolone group achieved remission within 11 (8-20) days of the corticosteroid initiation, whereas in the prednisolone group, 58 of 60 patients (96.7%) achieved remission within 19 (12-37) days (P<0.001). After achieving first remission, 32 (49.2%) patients in the methylprednisolone and prednisolone group and 43 (74.1%) patients in the prednisolone group developed at least one relapse. Multivariate Cox proportional hazards models revealed that methylprednisolone and prednisolone use was significantly associated with early remission (multivariate-adjusted hazard ratio, 1.56; 95% confidence interval, 1.06 to 2.30) and lower incidence of relapse (0.50; 95% confidence interval, 0.29 to 0.85) compared with prednisolone use alone. These results were ascertained in propensity score-based models. No significant difference was observed in incidence of adverse events, including infection, aseptic osteonecrosis, cataract, diabetes, and gastrointestinal bleeding. CONCLUSIONS: Initial use of methylprednisolone was associated with earlier remission and lower incidence of relapse in adult-onset minimal change disease patients. Efficacy of methylprednisolone should be evaluated in randomized controlled trials.

Age and prediction of remission and relapse of proteinuria and corticosteroid-related adverse events in adult-onset minimal-change disease: a retrospective cohort study.

BACKGROUND: In adult-onset minimal-change disease (MCD) the predictors of remission and relapse of proteinuria and corticosteroid-related adverse events remain unknown. METHODS: The multicenter retrospective cohort study, the STudy of Outcomes and Practice patterns of Minimal-Change Disease (STOP-MCD), included 142 adult-onset MCD patients in 5 nephrology centers in Japan. Primary outcomes were first remission of proteinuria defined by urinary protein (UP) <0.3 g/day, UP/creatinine ratio (UPCR) <0.3, and/or negative/trace by dipstick test and first relapse of proteinuria defined by UP ≥1.0 g/day, UPCR ≥1.0, and/or dipstick test ≥1+ followed by immunosuppressive therapy. Secondary outcomes were corticosteroid-related adverse events. RESULTS: During the median 3.6 (interquartile range, 2.0-6.9) years of the entire observational period, 136 (95.8 %) and 79 (58.1 %) patients developed at least 1 remission and 1 recurrence within a median of 15 (10-34) days and 0.90 (0.55-1.57) years, respectively. Compared with younger patients aged 15-29 years at kidney biopsy, elderly patients aged ≥60 years developed remission significantly later [hazard ratio 0.53 (95 % confidence interval 0.32-0.88)], while older patients aged ≥45 years were at a significantly lower risk of relapse [45-59 years, 0.46 (0.22-0.96); 60-83 years, 0.39 (0.21-0.74)]. However, older patients were significantly more vulnerable to severe infection, diabetes, and cataract as compared with younger patients. CONCLUSION: Younger patients had a higher risk of relapse while older patients had a lower risk of relapse but a higher risk of corticosteroid-related adverse events.

A case of anti-GBM glomerulonephritis superimposed on HBV-associated membranous nephropathy.

In September 2010, a 75-year-old hepatitis B virus (HBV)-positive man was admitted to our hospital because of fever, persistent cough, general fatigue, and leg edema. The patient was a hepatitis B surface antigen carrier with detectable HBV DNA level. On admission, laboratory examination revealed severe inflammatory signs, decreased serum albumin, and renal insufficiency with proteinuria. The patient had rapidly progressive renal insufficiency without pulmonary involvement over the few days after admission. Renal biopsy showed membranous nephropathy (MN) with crescent formation. Further serological study revealed a high titer of anti-glomerular basement membrane (GBM) antibody, suggestive of anti-GBM glomerulonephritis superimposed on HBV-associated MN. For both preventing HBV reactivation during immunosuppressive therapy and treating HBV-associated MN, the administration of entecavir was immediately initiated, and then treatment with plasma exchange (PE) and intravenous methylprednisolone administration was performed. Both HBV DNA level and an anti-GBM titer became undetectable, and clinical remission of MN was subsequently achieved. This was a rare case of an elderly patient with anti-GBM glomerulonephritis superimposed on HBV-associated MN, who was successfully treated with PE, corticosteroid, and entecavir combination therapy.

Tubular nephrotoxicity induced by docetaxel in non-small-cell lung cancer patients.

Renal dysfunction is a characteristic of many patients with cancer; however, a standard therapy has not been established for stage III or IV non-small-cell lung cancer (NSCLC) complicated with chronic renal failure. Docetaxel has a proven significant activity against NSCLC. This agent is predominantly eliminated by hepatobiliary extraction and is safe in patients with renal failure, including dialysis patients. Docetaxel is, thus, a therapeutic option in that patient population. Here, we report acute tubular nephrotoxicity secondary to docetaxel in NSCLC patients, even in patients with normal renal function. Little is known about tubular nephrotoxicity induced by docetaxel; however, oncologists should be aware of its possibility.

Smooth muscle alpha-actin deficiency in myofibroblasts leads to enhanced renal tissue fibrosis.

Myofibroblasts are a major source of proinflammatory cytokines and extracellular matrix in progressive tissue fibrosis leading to chronic organ failure. Myofibroblasts are characterized by de novo expression of smooth muscle alpha-actin (SMalphaA), which correlates with the extent of disease progression, although their exact role is unknown. In vitro cultured myofibroblasts from kidney of SMalphaA knock-out mice demonstrate significantly more prominent cell motility, proliferation, and type-I procollagen expression than those of wild-type myofibroblasts. These pro-fibrotic properties are suppressed by adenovirus-mediated SMalphaA re-expression, accompanied by down-regulation of focal adhesion proteins. In interstitial fibrosis model, tissue fibrosis area, proliferating interstitial cell number, and type-I procollagen expression are enhanced under SMalphaA deficiency. In mesangioproliferative glomerulonephritis model, cell proliferation in the mesangial area is also enhanced in SMalphaA knock-out mice. Adenoviral SMalphaA introduction into renal interstitium obviously ameliorates tissue fibrosis in interstitial fibrosis model. These results indicate that SMalphaA suppresses the pro-fibrotic properties of myofibroblasts, highlighting the significance of smooth muscle-related proteins in moderating chronic organ fibrosis under pathological conditions.

Impact of lowering dialysate calcium concentration on serum bone turnover markers in hemodialysis patients.

Loss of renal function perturbs bone metabolism because kidney is a vital organ maintaining homeostasis of calcium and phosphate. In hemodialysis patients, bone diseases are serious complications resulting in fractures and extraosseous calcification. The latest clinical practice guidelines by the National Kidney Foundation (New York, US) recommend a dialysate calcium concentration (D-Ca) of 2.5 mEq/L rather than 3.0 mEq/L to avoid excess calcium load and to prevent subsequent vascular calcification. However, there is no perfect agreement yet about which concentration should be chosen because lowering D-Ca might enhance uncoupled bone resorption. Here, we studied effects of lowering D-Ca from 3.0 to 2.5 mEq/L on bone metabolism in 67 patients. Doses of vitamin D and phosphate binders were kept constant for a 2-month period beginning 1 month before the change in D-Ca, and were adjusted thereafter. In group A [intact parathyroid hormone (iPTH) < 100 pg/ml before the study], serum cross-linked N-terminal telopeptide of type I collagen (NTx) increased immediately after lowering D-Ca and then remained stable. Intact osteocalcin (iOC) increased later along with iPTH, suggesting the improvement of adynamic bone disease which shows a marked decrease in bone turnover without osteoid accumulation. Vitamin D was not dosed up in this group. In group B (100 < or = iPTH < 300), serum NTx increased transiently, which is followed by an increase of iOC but not by a change of iPTH. In group C (300 < or = iPTH), lowering D-Ca allowed us to increase the dose of vitamin D without hypercalcemia, leading to a significant decrease in NTx and iPTH. Overall, serum phosphate increased from 5.4 +/- 1.6 to 6.1 +/- 1.6 mg/dL (P < 0.0001) and serum NTx increased by 1.5-fold (P < 0.0001) 1 month after lowering D-Ca. Over a 3-month period after that, serum phosphate and serum NTx decreased to their basal levels. These indicate that bone resorption predominated over formation for only a short period. In conclusion, a D-Ca of 2.5 mEq/L with adjustment of vitamin D ameliorates metabolic abnormalities of bone which develop under 3.0 mEq/L.

CCAAT/Enhancer-binding protein delta contributes to myofibroblast transdifferentiation and renal disease progression.

Myofibroblasts are pivotal participants in pathologic processes in a wide variety of organs, such as lung, liver, and kidney, by producing several inflammatory cytokines and extracellular matrices. The mechanism by which transdifferentiation from original cell to myofibroblast occurs, however, is still unclear. The expression of smooth muscle alpha-actin (SMalphaA) is the most characteristic feature of myofibroblasts; therefore, it was speculated that any factors that promote SMalphaA expression might be the key to transdifferentiation to myofibroblasts and disease exacerbation. A transcription factor CCAAT/enhancer-binding protein delta (C/EBPdelta) was identified and demonstrated to bind to sequences including the CArG motif from SMalphaA intron 1 and to increase transcriptional activity of this promoter. Expression of SMalphaA and C/EBPdelta in the glomerular area was upregulated in rat anti-Thy1 glomerulonephritis and mouse Habu-venom glomerulonephritis, both of which are models of mesangioproliferative glomerulonephritis. In the latter model, C/EBPdelta knockout mice demonstrated significantly less SMalphaA expression in the glomerular area on day 8 and less renal functional deterioration on day 14, compared with wild-type mice. These data suggest an important role for C/EBPdelta in myofibroblast transdifferentiation and glomerulonephritis exacerbation.

Therapeutic effect of all-trans retinoic acid on rats with anti-GBM antibody glomerulonephritis.

BACKGROUND: All-trans retinoic acid (ATRA) has antiproliferative and anti-inflammatory effects and is currently used in the treatment of leukemia and dermatologic diseases. We tested the therapeutic potential of ATRA on anti-glomerular basement membrane (GBM) glomerulonephritis rats. METHODS: Glomerulonephritis was induced in male Wistar-Kyoto rats on day 0 by an intravenous injection of antirat GBM antibody. On day 14 after the induction of anti-GBM glomerulonephritis, some rats were sacrificed (N = 5). Another 10 rats were divided into two groups: the vehicle group (N = 5) and the ATRA treated group (N = 5). ATRA was orally administrated from day 14 to day 27 after disease induction. Blood pressure, body weight, urinary protein excretion, and blood chemistry was determined on days 1, 14, 21, and 27. Kidney samples were obtained on day 28. The kidneys were examined with periodic acid-Schiff staining (PAS) and immunohistochemistry using antibodies against the proliferative cell nuclear antigen (PCNA), rat monocyte and macrophage (ED-1), and alpha-smooth muscle actin (alpha-SMA). Glomerular RNA was extracted from isolated glomeruli, and reverse transcription (RT) followed by polymerase chain reaction (PCR) was performed. RESULTS: ATRA administration produced a 55% reduction of proteinuria in glomerulonephritis rats. Light microscopic analysis revealed severe necrosis/crescent formation (>50% of the glomerulus) affecting 34% of glomeruli in vehicle rats, whereas ATRA treatment reduced the glomeruli showing severe change to 14%. ATRA also significantly reduced PCNA-positive cells, ED-1-positive cells and alpha-SMA-positive area in the glomeruli. RT-PCR analyses revealed that a wide variety of genes including inflammation related [tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and CCAAT enhancer-binding protein delta (C/EBPdelta)], cell proliferation-related [platelet-derived growth factor (PDGF)] and fibrosis-related [transforming growth factor-beta1 (TGF-beta1), type I collagen, and alpha-SMA) genes were suppressed in the glomeruli of ATRA-treated rats. CONCLUSION: ATRA administration significantly reduced severe necrosis/crescent formation and urinary protein excretion in glomerulonephritis rats. Suppression of a wide variety of gene expression may partly explain the mechanism of ATRA's antiproliferative and anti-inflammatory effects. These data suggest a novel therapeutic application of ATRA toward glomerulonephritis.

Y-27632 prevents tubulointerstitial fibrosis in mouse kidneys with unilateral ureteral obstruction.

BACKGROUND: The small GTPase Rho is involved in cell-to-substratum adhesion and cell contraction. These actions of Rho mediated by downstream Rho effectors such as Rho-associated coiled-coil forming protein kinase (ROCK) may be partly responsible for the progression of renal interstitial fibrosis. METHODS: The anti-fibrosis effects of Y-27632, a specific ROCK inhibitor, were studied both in vivo (unilateral ureteral obstruction; UUO) and in vitro. To investigate the therapeutic efficacy of Y-27632 in UUO kidneys, smooth muscle alpha actin (SMalphaA) expression, macrophage infiltration and fibrosis in the obstructed kidneys were studied. SMalphaA, transforming growth factor beta (TGF-beta), alpha1 (I) collagen, osteopontin, macrophage chemoattractant peptide-1 (MCP-1), and intercellular adhesion molecule-1 (ICAM-1) gene expression were examined by Northern blotting. To elucidate the mechanism linking the Rho-ROCK pathway with renal fibrosis, the effects of Y-27632 on in vitro cell proliferation and cell migration were studied. RESULTS: In vivo analysis showed that Y-27632 suppressed SMalphaA expression, macrophage infiltration and interstitial fibrosis, and that Y-27632 suppressed SMalphaA, TGF-beta and alpha1 (I) collagen mRNA expression. In vitro analysis showed that Y-27632 did not suppress proliferation of renal fibroblasts but suppressed migration of macrophages. CONCLUSIONS: The Rho-ROCK system may play an important role in the development of tissue fibrosis, and the Rho-ROCK signaling pathway may be a new therapeutic target for preventing interstitial fibrosis in progressive renal disease.