Idiopathic acute pancreatitis—A myth or reality? Role of endoscopic ultrasonography and magnetic resonance cholangiopancreatography in its diagnosis



Around 10% to 30% patients with acute pancreatitis (AP) do not have a cause after the routine investigations, and are considered as having idiopathic acute pancreatitis (IAP). Establishing the etiology in such patients will prevent recurrences and evolution to chronic pancreatitis. Endoscopic ultrasonography (EUS) and magnetic resonance cholangiopancreatography (MRCP) characteristically are used to diagnose IAP when routine methods fail, but their exact role is not determined.


This prospective study was undertaken in a tertiary care hospital, in which patients admitted initially with diagnosis of IAP were evaluated. These patients underwent MRCP and EUS at least 4 weeks after an attack of AP. The results of EUS and MRCP were compared and analyzed with various clinical variables using suitable statistical tests.


A total of 31 patients with IAP were included. EUS and/or MRCP was able to establish at least one etiology in 17 patients (54.8%). The diagnoses revealed were gallbladder (GB) microlithiasis, GB sludge, choledocholithiasis, pancreatobiliary ductal anomalies, pancreatic adenocarcinoma, and intraductal papillary mucinous neoplasm. Comparing the diagnostic accuracy of both the modalities, EUS (14/31) was able to diagnose more cases than MRCP (8/31). The diagnostic capability of EUS was lower in patients who had a cholecystectomy (12.5% vs. 56.5%; p = 0.03).


EUS and MRCP are useful modalities in the etiological diagnosis of IAP and should be used in conjunction. EUS is better for establishing a possible biliary etiology and MRCP for an anatomical alteration in pancreatobiliary ducts.

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The authors acknowledge the contribution of all the nursing and endoscopy staff of the department of gastroenterology, Sir Sunderlal Hospital, Varanasi.

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Correspondence to Vinod Kumar Dixit.

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TM, VKD, DPY, SKS, AV, PT, and RT declare that they have no conflict of interest.

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The study was performed conforming to the Helsinki declaration of 1975, as revised in 2000 and 2008 concerning human and animal rights, and the authors followed the policy concerning informed consent as shown on

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The ethical clearance for the study was obtained from the Institutional Ethical Committee. Informed consent was obtained from each participant in their native language.


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Mitra, T., Dixit, V.K., Yadav, D.P. et al. Idiopathic acute pancreatitis—A myth or reality? Role of endoscopic ultrasonography and magnetic resonance cholangiopancreatography in its diagnosis. Indian J Gastroenterol (2021).

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  • Biliary sludge
  • Chronic pancreatitis
  • Endoscopic retrograde cholangiopancreatography
  • Endoscopic ultrasonography
  • Gallstone
  • Magnetic resonance cholangiopancreatography
  • Microlithiasis
  • Pancreas divisum
  • Pancreatitis