Long-term follow-up of low-dose methotrexate therapy in one case of idiopathic retroperitoneal fibrosis.

Idiopathic retroperitoneal fibrosis (RPF) is characterized by the development of a fibrotic mass surrounding the abdominal aorta and its branches, of unknown aetiology. Several immunological mechanisms can be operative in the pathogenesis of RPF. Based on this assumption we treated a patient affected by idiopathic RPF with low-dose methotrexate (MTX) therapy. To our knowledge this is the first example of the effectiveness and safety of a long-term low-dose MTX treatment in the post-surgical management of RPF.