Remission of "mistletoe sign" after treatment.

We described a 55-year-old man, in whom the first manifestation of retroperitoneal fibrosis (RPF) was only coronary arterial involvement, which had no periaortic or peri-iliac and urinary system retroperitoneum involvement in general and other systemic clinical manifestations. Coronary manifestation was called "mistletoe sign" on the images. Here, we report a case of IgG4-related RPF remission that was only coronary arterial involvement after treatment.