Weight Loss in Obese Kidney Disease Patients After Bariatric Surgery

Inclusion Criteria: * Age 18-70 years (male or female). * BMI \>35 kg/m2 who meet the following criteria: 1. GFR 30-60 ml/min and proteinuria\>1g/24 hours despite receiving maximally tolerated doses of blocking the renin-angiotensin system. 2. GFR \>60 ml/min and proteinuria \>(3.5) 2.5 g/24 hours despite receiving maximally tolerated doses of blocking the renin-angiotensin system. * Patients with BMI\> 40 kg/m2 with a GFR\> 30 ml/min and proteinuria \>(1) 0.5 g/24 hours despite receiving maximally tolerated doses of blocking the renin-angiotensin system. * Patients who are able to understand the purpose and risks of the study, which has been fully informed and have finally given the written informed consent according to the ICH-GCP. Patients who can not read or write but who properly understand the verbal information provided by the investigator (or sub-investigator) the consent will be granted orally before their inclusion and an independent witness will signing the informed consent document. Exclusion Criteria: * Subjects who are participating or have participated in another clinical trial and/or who are taking or have taken an experimental drug (not registered) in the last 28 days. * Patients with chronic renal replacement therapy (hemodialysis and/or peritoneal dialysis) and/or renal transplantation. * Patients with poorly controlled blood pressure (SBP\> 170 mmHg or DBP\> 110 mmHg). * Patients with a history of cardiovascular events (stroke, ischemic heart disease) in the past six months. * Patients treated with steroids or other immunosuppressants. * Patients with a history of renovascular disease, obstructive uropathy, autoimmune diseases, cancer, drug use. * Patients who are pregnant or lactating. * Patients who do not sign the informed consent. * A slight chance of compliance with visits scheduled in the protocol.