CASE 17264 Published on 12.05.2021

Meandering Main Pancreatic Duct - a cause for recurrent acute pancreatitis

Section

Abdominal imaging

Case Type

Clinical Cases

Authors

Amol Anil Kulkarni, Nikhil V Kamat, Muktachand L Rokade, Kalashree Devdutt Bandekar

Radiology Department, Jupiter Hospital, Thane, Maharashtra, India

Patient

20 years, male

Categories
Area of Interest Abdomen, Pancreas ; Imaging Technique CT, MR-Cholangiography
Clinical History

A 20-years-old non-smoker/non-alcoholic male suffered from two episodes of acute pancreatitis in the last 6 months. The last episode occurred one month ago. The episodes were unprovoked with raised Sr.lipase & Sr.amylase levels. Both episodes were managed conservatively. Investigations including LFT, Lipid profile, Sr.calcium, Sr. PTH were normal.

Imaging Findings

Contrast-enhanced CT of abdomen and pelvis was performed. It showed resolving changes of pancreatitis in the form of small acute fluid collection near the pancreatic tail/splenic hilar region. No evidence of parenchymal/ductal calcifications. No evidence of pseudocyst formation. Rest of the abdominal organs appeared unremarkable (Figure 1)

MRCP showed an abnormal course of the main pancreatic duct which looped around in the region of head/uncinate process. Also seen, is early visualization of pancreatic side branches suggestive of chronicity (Grade 1 Cambridge Classification). No suggestion of pancreatic divisum or annular pancreas. The gall bladder walls were smooth. No evidence of Gall bladder calculi or sludge. The CBD appeared normal in course and calibre. No evidence of CBD calculi. (Figure 2)

Discussion

Pancreatitis is a serious condition with significant morbidity & sometimes fatal outcomes. Common causes include alcohol, biliary calculi, congenital anomalies, autoimmune, trauma, metabolic. Approximately 20–30% of cases of acute pancreatitis remain idiopathic.[1]

Congenital anomalies of pancreatic duct include variations of the course & configuration. The most common type is descending course and bifid configuration with dominant duct of Wirsung drainage.[2]

Meandering main pancreatic duct (MMPD) is anatomical variation in course of the main pancreatic duct without an abnormal pancreaticobiliary junction. Gonoi et al have classified MMPD into various subtypes viz loop type and reverse Z-type (Figure 3). These ductal variants can be detected in Endoscopic Retrograde Cholangiopancreatography (ERCP) and Magnetic Resonance Cholangiopancreatography (MRCP) studies. Increased incidence of MMPD has been reported in patients with idiopathic recurrent acute pancreatitis (40%) compared with subjects from community population (2.2%).[3] MMPD is also a cause of pancreatitis in children. [4]

The exact aetiology and pathophysiology of pancreatitis in MMPD are not well established. It has been postulated that abnormal course leads to ductal hypertension and causes pancreatitis.[1]

3D MRCP is the investigation of choice in the diagnosis of ductal anomalies. Heavily T2-weighted MRCP easily and accurately detects MMPD. ERCP is difficult due to abnormal curvature and bends in the MPD and hence its role is not well established. [1-7]

Presently there are no standardized protocols for management of pancreatitis in MMPD. Treatment is similar to pancreatitis due to other causes. [1,6]

Take-Home Message: Meandering main pancreatic duct is a rare cause of recurrent idiopathic pancreatitis. Knowledge of these lesser described pancreatic ductal variants is essential for diagnosis and management. MRCP being non-invasive is the investigation of choice for diagnosing ductal anomalies.

Written informed patient consent for publication has been obtained.

Differential Diagnosis List
Meandering Main Pancreatic duct with resolving changes of pancreatitis
Idiopathic pancreatitis
Ansa pancreatica
Normal variant
Final Diagnosis
Meandering Main Pancreatic duct with resolving changes of pancreatitis
Case information
URL: https://www.eurorad.org/case/17264
DOI: 10.35100/eurorad/case.17264
ISSN: 1563-4086
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