1Department of Gastroenterology, Sapporo Tokusyukai Hospital, 18-4-10 Sakaedori Shiroishi-ku Sapporo-shi 003-0021, Japan, 2Department of Gastroenterology, Toranomon Hospital 2-2-2 Toranomon Minato-ku Tokyo 105-8470, Japan, 3Second Department of Internal Medicine, Toho University, School of Medicine 5-21-16 Oomorinishi Oota-ku Tokyo 143-8540, Japan, 4Department of Internal Medicine, Teikyo University, School of Medicine 2-11-1 kaga Itabashi-ku Tokyo 173-8605, Japan
The concept of autoimmune pancreatitis has recently been established, and ultrasonographic findings we obtained from five
cases consistent with autoimmune pancreatitis are reported here. Case 1 a 77-year-old man, was admitted complaining of loss
of body weight. Serum hepatobiliary enzymes and γ-globulin levels were elevated, and antinuclear antibody was positive.
Abdominal ultrasonography showed dilatation of the intrahepatic bile duct, wall thickening of the common bile duct and
hypoechoic swelling of the pancreatic head and body. ERCP revealed multiple stenosis of the intra- and extra-hepatic bile ducts,
and diffuse irregular narrowing of the main pancreatic duct. The patient complained of thirst, and the minor salivary gland was
examined histologically. Our diagnosis was Sjögren syndrome accompanied by sclerosing cholangitis and a pancreatic lesion.
Obstructive jaundice also developed, and PTCD was therefore performed. Both the pancreatic swelling and multiple stenosis of
the bile duct improved after steroids were administered. Case 2, a 71-year-old man, was admitted with jaundice. Abdominal
ultrasonography showed hypoechoic swelling of the pancreas; ERCP showed stenosis of the common bile duct in the pancreatic
head region and diffuse irregular narrowing of the main pancreatic duct. Histological examination of the minor salivary gland
suggested Sjögren syndrome. Steroids were therefore administered because the presence of both hyper-γ-globulinemia and
positive antinuclear antibody suggested involvement of the autoimmune mechanism. Steroid therapy improved the jaundice as
well as the findings from the cholangiograms and pancreatograms. We also encountered three similar cases, all consistent with
the concept of autoimmune pancreatitis. The ultrasonographic findings of the pancreatic lesion (1) showed them as homogeneous and markedly hypoechoic areas and, (2) visualized the main pancreatic duct in the lesion, which allowed for a differential
diagnosis of the neoplastic lesions. (3) Steroid therapy effectively decreased the hypoechoic area; in some cases, however, a
hypoechoic area remained around the main pancreatic duct.