Treatment with alternative immunosuppressive regimen for idiopathic non-IgG4-related retroperitoneal fibrosis in patients with contraindications to high-dose glucocorticoids

IgG4: immunoglobulin G4; CT: computed tomography; MRI: magnetic resonance imaging; ESR: erythrocyte sedimentation rate; CRP: C-reactive protein; FDG-PET: 18F-fluorodeoxyglucose positron emission tomography; IV: intravenously.

* Choice between individual regimens depends upon contraindications to individual agents. Refer to the UpToDate topic on treatment of retroperitoneal fibrosis for additional information.

• Methotrexate: 7.5 to 10 mg orally once weekly and increase by 2.5 mg/week to a maximum total dose of 20 mg/week
• Mycophenolate mofetil: 1 g orally twice daily
• Rituximab: 375 mg/m² IV once weekly for 4 weeks or 1 g IV every 2 weeks for 2 doses

Δ Improvement in ESR and CRP and, if applicable, serum creatinine may be noted but is not required to define response to therapy.