Ansa pancreatica as a predisposing factor for recurrent acute pancreatitis.
OBJECTIVE
To determine the non-biased prevalence and clinical significance of ansa pancreatica in patients with acute pancreatitis using magnetic resonance imaging (MRI).


METHODS
Our institutional review board approved this cross-sectional study, which consisted of a community-based cohort of 587 consecutive participants in a whole-body health-check program, and 73 subjects with episode of acute pancreatitis (55 patients with a single episode of acute pancreatitis, and 18 patients with recurrent acute pancreatitis). All of the subjects underwent abdominal MRI including magnetic resonance cholangiopancreatography, medical examinations, and blood tests. Two board-certified, diagnostic, abdominal radiologists evaluated the images, and ansa pancreatica was diagnosed based on its characteristic anatomy on MRI.


RESULTS
Compared with the community group [5/587 (0.85%)], patients with recurrent acute pancreatitis had a significantly higher frequency of ansa pancreatica [2/18 (11.1%)] (P= 0.016; OR = 14.3; 95%CI: 1.27-96.1), but not compared with patients with single-episode acute pancreatitis [1/55 (1.8%)] (P= 0.42; OR = 2.1; 95%CI: 0.44-19.7). Multiple logistic regression analysis using age, alcohol intake, presence of ansa pancreatica, and presence of autoimmune disease as independent covariates, revealed a significant relationship between the presence of ansa pancreatica and recurrent acute pancreatitis. The presence of autoimmune disease was also significantly associated with the onset of recurrent acute pancreatitis. On the other hand, neither age nor alcohol intake were significantly related to the onset of recurrent acute pancreatitis.


CONCLUSIONS
The present study is the first to provide robust evidence that the presence of ansa pancreatica is significantly associated with recurrent acute pancreatitis.
Takana Yamakawa Hayashi, Wataru Gonoi, Kuni Ohtomo, Department of Radiology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan.
Takana Yamakawa
TY
Hayashi
Takana Yamakawa Hayashi, Wataru Gonoi, Kuni Ohtomo, Department of Radiology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan.
Wataru
W
Gonoi
Takana Yamakawa Hayashi, Wataru Gonoi, Kuni Ohtomo, Department of Radiology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan.
Takeharu
T
Yoshikawa
Takana Yamakawa Hayashi, Wataru Gonoi, Kuni Ohtomo, Department of Radiology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan.
Naoto
N
Hayashi
Takana Yamakawa Hayashi, Wataru Gonoi, Kuni Ohtomo, Department of Radiology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo 113-8655, Japan.
Kuni
K
Ohtomo
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D006801:Humans; D008875:Middle Aged; D010183:Pancreatic Ducts / Q000002:abnormalities*; D010195:Pancreatitis / Q000209:etiology*; D055815:Young Adult
Anatomy; Cholangiopancreatography; Magnetic resonance imaging; Pancreatic duct; Pancreatitis