Inclusion Criteria:  Age of the patient between 18 and 80 years, Patients diagnosed with systemic lupus erythematosus according to ACR 1997 or SLICC-2012 criteria Diagnosis of proliferative lupus nephritis class III, IV +/- V (confirmed by renal biopsy and classified according to ISN / RPS); Estimated glomerular filtration rate by CKD-EPI> 30 ml / min / 1.73 sqm Estimated glomerular filtration rate by CKD-EPI <30 ml / min / 1.73 sqm but> 15 ml / min / 1.73 sqm with chronicity index (according to NIH score) <6 Absence of contraindications to the use of Methylprednisolone, Mycophenolate mofetil, oral corticosteroids or Rituximab Ability to provide informed consent  Exclusion Criteria:  The patient's age under 18 years Patients with life-threatening complications (e.g. Cerebritis) Estimated glomerular filtration rate by CKD-EPI <30 ml / min / 1.73 sqm Estimated glomerular filtration rate by CKD-EPI <30 ml / min / 1.73 sqm but> 15 ml / min / 1.73 sqm with chronicity index (according to NIH score)> 6 Presence of pregnancy / lactation Patients who have received more than 2 g of Methylprednisolone intravenously in the last 4 weeks Use in the last 3 months of biological therapy Use of intravenous immunoglobulins / plasmapheresis in the last 6 months The presence of an active infection History of neoplasia Comorbidities requiring systemic corticosteroid therapy Non-adhesion