title: Endoscopic ultrasonographic study of autoimmune pancreatitis and the effect of steroid therapy.
abstract: BACKGROUND
  Recently, endoscopic ultrasonography (EUS) has been used for the diagnosis of chronic pancreatitis (CP); however, EUS diagnosis of autoimmune pancreatitis (AIP) varies among different researchers. We investigated EUS findings in AIP and retrospectively analyzed them before and after steroid therapy.
  
  
  METHODS
  The subjects were 32 patients with AIP and the EUS images of the pancreatic parenchyma were evaluated with reference to the Sahai criteria. Patients' background factors detected by EUS were analyzed statistically. Peroral steroid was given to 23 of the 32 patients. EUS was also performed 2 weeks after the initiation of therapy in 14 of the 23 patients, and the changes in EUS were investigated. Microscope images were compared with EUS images in one patient who underwent surgical resection.
  
  
  RESULTS
  EUS results included hyperechoic strands in 26 (81.3%) and lobularity in 17 (53.1%) patients. The patients' background factors included the presence of splenic and/or portal vein occlusion or narrowing around the pancreas in patients who had neither hyperechoic strands nor lobularity (p = 0.002, p = 0.004). The numbers of EUS findings before versus after steroid therapy were 11 versus 5 for hyperechoic strands and 7 versus 2 for lobularity. Microscope images showed the coexistence of relatively well-maintained lobular structures of pancreatic acini and almost complete loss of such structures.
  
  
  CONCLUSIONS
  EUS findings in AIP were similar to those in early-stage CP, and hyperechoic strands and lobularity seem to suggest a condition under which the histology of lobular structures of the pancreatic acini is relatively well-maintained. EUS results had improved within about 2 weeks of steroid therapy.
authors.affiliation: Division of Gastroenterology, Department of Medicine, Kurume University School of Medicine, 67 Asahi-machi, Kurume 830-0011, Japan. okabe_yoshinobu@kurume-u.ac.jp
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Okabe
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Ishida
authors.forename: Ryohei
authors.initials: R
authors.lastname: Kaji
authors.forename: Gen
authors.initials: G
authors.lastname: Sugiyama
authors.forename: Makiko
authors.initials: M
authors.lastname: Yasumoto
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Naito
authors.forename: Atsushi
authors.initials: A
authors.lastname: Toyonaga
authors.forename: Osamu
authors.initials: O
authors.lastname: Tsuruta
authors.forename: Michio
authors.initials: M
authors.lastname: Sata
mesh_terms: D000284:Administration, Oral; D001327:Autoimmune Diseases / Q000000981:diagnostic imaging* / Q000188:drug therapy; D004305:Dose-Response Relationship, Drug; D019160:Endosonography / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D005938:Glucocorticoids / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D010179:Pancreas / Q000000981:diagnostic imaging / Q000473:pathology; D050500:Pancreatitis, Chronic / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000473:pathology; D011239:Prednisolone / Q000008:administration & dosage*; D011379:Prognosis; D012189:Retrospective Studies; D012720:Severity of Illness Index
chemical_list: D005938:Glucocorticoids; D011239:Prednisolone