Retroperitoneal fibrosis: some new acquisitions about pathogenesis and diagnostics.

Some newly proposed pathogenetic theories for retroperitoneal fibrosis refer to immune-related mechanisms; they are reviewed and discussed. In the field of imaging techniques, some MR paramagnetic contrast media, such as "ferrite" compounds and Gd-DTPA, and 67Ga-scintiscan, 111In-labelled leukocytes scan, 99mTc-labelled colloids contribute to answering the request to differentiate the still active cellulitis from an established fibrosis. 131I-MIGB scan identifies the carcinoid-related retroperitoneal fibrosis.