Currently, Ormond's disease is classified among IgG4-associated diseases. Its clinical manifestation varies and is characterized by the presence of fibrous retroperitoneal tissue that often affects the ureters or abdominal aorta and iliac arteries. We present a unique case of the polycystic form of Ormond's disease, imitating tumour in the retroperitoneal space. At the time of diagnosis, the disease was not metabolically active and did not require immunosuppressive therapy. The polycystic mass was removed surgically. There has been no exacerbation of the disease during the last 12 months.
Keywords: Ormond’s disease; Polycystic form; Retroperitoneal fibrosis.