Diagnostic utility of biopsy specimens for autoimmune pancreatitis.
OBJECTIVE
Infiltration of IgG4-positive plasma cells in the pancreas and other organs is characteristic of autoimmune pancreatitis (AIP). However, it is undetermined whether needle or forceps biopsy of pancreas or other organs is indeed useful for the diagnosis of AIP. We aimed to clarify this point.


METHODS
Among 39 AIP patients, tissue sampling without laparotomy was performed in 27. Biopsy of pancreas, gastric mucosa, liver, bile duct, and duodenal papilla was performed in 15, 17, 11, 5 and 7, respectively. The obtained specimens were examined for IgG4-positive plasma cells. We also examined gastric mucosa of 18 patients with pancreatic cancer as controls. When the number of IgG4-positive plasma cells was more than 10 per high-power field, we regarded it as diagnostic.


RESULTS
Diagnostic sensitivity in pancreas, gastric mucosa, liver, bile duct, and duodenal papilla was 47% (7/15), 47% (8/17), 36% (4/11), 0% (0/5), and 57% (4/7), respectively.


CONCLUSIONS
Sensitivity of IgG4 immunostaining was unsatisfactory when tissue sampling was performed by needle or forceps biopsy. Biopsy of gastric mucosa might be a good subsidiary diagnostic tool.
Hirano
Kenji
K
Department of Gastroenterology, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8655, Japan. khirano-tky@umin.ac.jp
Fukushima
Noriyoshi
N
Tada
Minoru
M
Isayama
Hiroyuki
H
Mizuno
Suguru
S
Yamamoto
Keisuke
K
Yashima
Yoko
Y
Yagioka
Hiroshi
H
Sasaki
Takashi
T
Kogure
Hirofumi
H
Nakai
Yousuke
Y
Sasahira
Naoki
N
Tsujino
Takeshi
T
Kawabe
Takao
T
Fukayama
Masashi
M
Omata
Masao
M
D000328:Adult; D000368:Aged; D001327:Autoimmune Diseases / Q000175:diagnosis* / Q000473:pathology; D001652:Bile Ducts / Q000473:pathology; D001706:Biopsy / Q000379:methods*; D001707:Biopsy, Needle; D002452:Cell Count; D004386:Duodenum / Q000473:pathology; D005260:Female; D005753:Gastric Mucosa / Q000473:pathology; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis* / Q000097:blood; D008099:Liver / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010183:Pancreatic Ducts / Q000473:pathology; D010195:Pancreatitis / Q000175:diagnosis* / Q000473:pathology; D010950:Plasma Cells / Q000276:immunology* / Q000473:pathology; D011379:Prognosis
D007074:Immunoglobulin G