Glomerular Disease

Background: * Membranous nephropathy is associated with damage to the walls of the glomeruli, the small blood vessels in the kidneys that filter waste products from the blood. This damage causes leakage of blood proteins into the urine and is associated with low blood protein levels, high blood cholesterol values, and swelling of the legs. These problems can decrease or go away without treatment in about 25 percent of patients, but if they persist, some patients may experience impaired (or loss of) kidney function, blood vessel and heart disease, and a risk of forming blood clots in veins. * Kidney biopsies that show that antibodies have been deposited along the glomeruli suggest that specialized cells of the immune system, called B and T cells, are causing damage to the kidneys through their increased activity. To suppress the action of B and T cells and to decrease the harmful deposits in the kidneys, drug treatments are required. * Patients with membranous nephropathy are often treated with immunosuppressive drugs such as cyclosporine or cytoxan plus steroids that attempt to reduce or suppress the activity of the immune system, decrease antibody production, and reduce antibody deposits in the kidney. However, not everyone responds to these medications and the kidney disease can return in some patients when the drugs are stopped. Also, there are side effects associated with long term usage of these medications. Rituximab, a different immunosuppressant, has also been used for this purpose. Although cyclosporine and Rituximab have been used separately, they have not been tried in combination as a possible treatment for membranous nephropathy. Objectives: \- To determine the safety and effectiveness of combining rituximab and cyclosporine to treat membranous nephropathy. Eligibility: \- Individuals 18 years of age and older who have been diagnosed with membranous nephropathy based on a kidney biopsy done within the preceding 24 months, and who have had excess levels of protein in the urine for at least 6 months based on urine and blood tests. Design: * Potential participants will be screened with an initial clinic evaluation and full medical history. * Before the treatment, there will be a run-in period that will last up to 2 months. During this time, participants will be placed on a blood pressure lowering medication and will not take any other immunosuppressant medications. * Participants will visit the NIH clinical center for a baseline evaluation, four intravenous infusions of rituximab, and also at 1- to 6-month intervals throughout the study. * Active treatment period will involve a 6-month course of cyclosporine and a total of four doses of rituximab. Participants will take cyclosporine tablets twice daily, and have two infusions of rituximab given 2 weeks apart, After 6 months, the cyclosporine dose will slowly be decreased over several weeks and then completely discontinued. Participants will then receive another course (two doses 2 weeks apart) of rituximab, depending on results of blood work. * Participants will have frequent blood and urine tests performed to monitor the results of treatment and reduce the chance of side effects.

The purpose of this study is to determine if zigakibart is safe and effective for long-term use in patients with immunoglobulin A nephropathy (IgAN). This is an extension study for patients who have already completed an another zigakibart study.

This is a multicenter, randomized, double-blind, parallel, placebo-controlled study and is being conducted to evaluate the efficacy and safety of HS-10542 capsules for primary IgA nephropathy.

Researchers from the University of Michigan and Northwestern University are studying people's experiences with swelling caused by Nephrotic Syndrome. Interviews with patients (child and adult) and parents of young children will be conducted. The information collected from the interviews will be used to develop a survey to use when testing new medications for Nephrotic Syndrome. Please consider participating in a 1-hour long interview with the Prepare-NS research study to discuss children and adults experiences with swelling.

The primary objectives of this study are to: (1) determine the impact of glomerular disease on bone strength and (2) investigate the pathophysiologic underpinnings of impaired bone strength in glomerular disease.

Glomerulonephritis (GN) generates an enormous individual and social economic burden. However, the therapeutic options are largely based on clinical and pathological parameters and the individual response to therapy or prognosis is uncertain. Recently, along with advances in molecular analysis and computational bioinformatics, genomic data from human renal biopsies could provide a strong foundation for the future of precision medicine in nephrology. In response to a request for applications by the Ministry of Health and Welfare of Korea for the creation of Clinical Research Registry, multi-center N network has been established for prospective cohort with kidney biopsy samples (KORNERSTONE). Through this Network the investigators hope to understand the fundamental biology of glomerulonephritis and aim to bank long-term observational data and corresponding biological data including genomic data from kidney tissues, and kidney pathologic data which is digitalized This database is archived to a web-based platform to access easily and further enrich for researchers.