Randomized trials of rituximab in primary membranous nephropathy (PMN) have not been conducted. We undertook a multicenter, randomized, controlled trial at 31 French hospitals (NCT01508468). Patients with biopsy-proven PMN and nephrotic syndrome after 6 months of nonimmunosuppressive antiproteinuric treatment (NIAT) were randomly assigned to 6-month therapy with NIAT and 375 mg/m intravenous rituximab on days 1 and 8 (n=37) or NIAT alone (n=38). Median times to last follow-up were 17.0 (interquartile range, 12.5-24.0) months and 17.0 (interquartile range, 13.0-23.0) months in NIAT-rituximab and NIAT groups, respectively. Primary outcome was a combined end point of complete or partial remission of proteinuria at 6 months. At month 6, 13 (35.1%; 95% confidence interval [95% CI], 19.7 to 50.5) patients in the NIAT-rituximab group and eight (21.1%; 95% CI, 8.1 to 34.0) patients in the NIAT group achieved remission (P=0.21). Rates of antiphospholipase A2 receptor antibody (anti-PLA2R-Ab) depletion in NIAT-rituximab and NIAT groups were 14 of 25 (56%) and one of 23 (4.3%) patients at month 3 (P<0.001) and 13 of 26 (50%) and three of 25 (12%) patients at month 6 (P=0.004), respectively. Eight serious adverse events occurred in each group. During the observational phase, remission rates before change of assigned treatment were 24 of 37 (64.9%) and 13 of 38 (34.2%) patients in NIAT-rituximab and NIAT groups, respectively (P<0.01). Positive effect of rituximab on proteinuria remission occurred after 6 months. These data suggest that PLA2R-Ab levels are early markers of rituximab effect and that addition of rituximab to NIAT does not affect safety.

COL4A1 may be a candidate gene in unexplained familial syndromes with autosomal dominant hematuria, cystic kidney disease, intracranial aneurysms, and muscle cramps.

INF2 mutations appear to cause many cases of FSGS-associated Charcot-Marie-Tooth neuropathy, showing that INF2 is involved in a disease affecting both the kidney glomerulus and the peripheral nervous system. These findings provide new insights into the pathophysiological mechanisms linking formin proteins to podocyte and Schwann-cell function. (Funded by the Agence Nationale de la Recherche and others.).

Type I cryoglobulinemia vasculitis (CryoVas) is considered a life-threatening condition; however, data on the characteristics and outcome are scarce. To analyze the presentation, prognosis, and efficacy and safety of treatments of type I CryoVas, we conducted a French nationwide survey that included 64 patients with type I CryoVas between January 1995 and July 2010: 28 patients with monoclonal gammopathy of unknown significance (MGUS) and 36 with hematologic malignancy.Type I monoclonal CryoVas was characterized by severe cutaneous involvement (necrosis and ulcers) in almost half the patients and high serum cryoglobulin levels, contrasting with a lower frequency of glomerulonephritis than expected. The 1-, 3-, 5-, and 10-year survival rates were 97%, 94%, 94%, and 87%, respectively. Compared to MGUS, type I CryoVas related to hematologic malignancy tended to be associated with a poorer prognosis. Therapeutic regimens based on alkylating agents, rituximab, thalidomide or lenalinomide, and bortezomib showed similar efficacy on vasculitis manifestations, with clinical response rates from 80% to 86%.Data from the CryoVas survey show that the prognosis of type I CryoVas does not seem to be as poor as previously suggested. Besides alkylating agents, the use of regimens based on rituximab, thalidomide or lenalinomide, and bortezomib are interesting alternative options, although the exact role of each strategy remains to be defined.

Alport syndrome is an inherited nephropathy associated with mutations in genes encoding type IV collagen chains present in the glomerular basement membrane. COL4A5 mutations are associated with the major X-linked form of the disease, and COL4A3 and COL4A4 mutations are associated with autosomal recessive and dominant forms (thought to be involved in 15% and 1%-5% of the families, respectively) and benign familial hematuria. Mutation screening of these three large genes is time-consuming and expensive. Here, we carried out a combination of multiplex PCR, amplicon quantification, and next generation sequencing (NGS) analysis of three genes in 101 unrelated patients. We identified 88 mutations and 6 variations of unknown significance on 116 alleles in 83 patients. Two additional indel mutations were found only by secondary Sanger sequencing, but they were easily identified retrospectively with the webbased sequence visualization tool Integrative Genomics Viewer. Altogether, 75 mutations were novel. Sequencing the three genes simultaneously was particularly advantageous as the mode of inheritance could not be determined with certainty in many instances. The proportion of mutations in COL4A3 and COL4A4 was notably high, and the autosomal dominant forms of Alport syndrome appear more frequently than reported previously. Finally, this approach allowed the identification of large COL4A3 and COL4A4 rearrangements not described previously. We conclude that NGS is efficient, reduces screening time and cost, and facilitates the provision of appropriate genetic counseling in Alport syndrome.

Data on the clinical spectrum and therapeutic management of noninfectious mixed cryoglobulinemia vasculitis (CryoVas) in the era of hepatitis C virus screening are lacking. We analyzed data from 242 patients with noninfectious mixed CryoVas included in the French multicenter CryoVas survey. Baseline manifestations were purpura (75%), peripheral neuropathy (52%), arthralgia or arthritis (44%), glomerulonephritis (35%), cutaneous ulcers (16%), and cutaneous necrosis (14%). A connective tissue disease was diagnosed in 30% and B-cell non-Hodgkin lymphoma in 22%, whereas the CryoVas was considered to be essential in 48%. With the use of Cox-marginal structural models, rituximab plus corticosteroids showed the greater therapeutic efficacy compared with corticosteroids alone and alkylating agents plus corticosteroids to achieve complete clinical, renal, and immunologic responses and a prednisone dosage < 10 mg/d at 6 months. However, this regimen was also associated with severe infections, particularly when high doses of corticosteroids were used, whereas death rates did not differ between the therapeutic regimens. The role of each of these strategies remains to be defined in well-designed randomized controlled trials. (Blood. 2012; 119(25):5996-6004)

SummaryBackground and objectives Several different entities have recently been described among glomerular diseases associated with monoclonal IgG deposits. The aim of this study was to describe the distribution of the different pathologic subtypes of IgG-associated glomerulopathy and to evaluate the IgG isotype involved in these diseases.Design, setting, participants, & measurements This was a retrospective study including all patients with glomerular deposits of monoclonal IgG referred to three nephrology departments between 1980 and 2008.Results Twenty-six patients were included. Nephrotic syndrome was almost constantly associated with a renal dysfunction in 14 of 26 patients. The presence of M-spike was detected in only 30% of the patients, and an overt hematologic malignancy (myeloma, lymphoma) was identified in 9 of 26 patients. Patients were almost equally divided into two distinct histologic patterns: membranous nephropathy (MN) or membranoproliferative glomerulonephritis (MPGN). IgG3 deposits were identified in 80% of patients with MPGN, whereas IgG1 deposits were present in 64% of patients with MN. Ultrastructural study showed that immune deposits were nonorganized in most patients. Seven patients were treated with rituximab with excellent results: five of seven had a complete remission of the nephrotic syndrome and two of seven had a partial response. After a mean 24-month follow-up, only one patient experienced relapse of the nephropathy.Conclusions GN with monoclonal Ig deposits can be associated with MPGN or MN, which are correlated with IgG3 and IgG1 isotypes, respectively. Rituximab appears to have a very favorable benefit-to-risk ratio for patients with no overt hematologic malignancy.

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