It’s good to be connected: A case report of disconnected pancreatic duct syndrome

A 38-year male presented to the emergency with acute epigastric pain that radiated to his back. He had necrotizing pancreatitis 3 months prior following which he suffered two episodes of recurrent pancreatitis. On examination, he had epigastric tenderness and abdominal rigidity. At the time of the presentation, the patient was conscious, oriented and had tachycardia. On hematological examination, white cell count was elevated -14×10^9/L with elevated lipase levels of 1400 U/L (normal: 0-160 U/L), amylase levels of 190 U/L (normal: 40-140 U/L).

MRI abdomen revealed a cystic area with well-formed hypointense margins and internal T2 hypointense debris in the proximal body of the pancreas (Figures 1 and 2). Given the previous history of acute necrotizing pancreatitis, features are suggestive of walled-off necrosis. The distal pancreatic parenchyma is normal in contour and signal. The upstream pancreatic duct is seen opening on the posterior aspect of the walled-off necrosis (Figures 1b and 1c). Disruption of continuity of the main pancreatic duct is seen. Features are suggestive of disconnected pancreatic duct syndrome (DPDS). Peripancreatic fat stranding is seen, suggesting inflammatory changes (Figure 3). 3D oblique MRCP image shows communication of the main pancreatic duct (MPD) with the walled-off necrosis (Figure 4) with loss of normal continuity of the duct. On the basis of the imaging features, a diagnosis of DPDS with walled-off necrosis is made. The patient was subsequently treated by drainage of the fluid collection by endoscopic retrograde cholangiopancreatography (ERCP) guided stent placement across disrupted ends of the MPD.

Background

DPDS is a condition characterized by loss of continuity of the pancreatic duct between viable secreting distal pancreatic tissues and the gastrointestinal tract [1]. The disconnection may occur following acute or chronic pancreatitis, surgery and abdominal trauma which lead to necrosis of the pancreatic duct. The most common site of involvement of the pancreatic duct is in the pancreatic head or body. This disruption results in leakage of pancreatic secretions in the extra-ductal pancreatic tissue which causes autolysis of pancreatic parenchyma surrounding the site of leakage [1-3]. Disruption of the duct can be complete or partial and the severity of the condition depends on it.

Clinical Perspective

DPDS as the name suggests results from discontinuity of the pancreatic duct. Studies reveal that about 16–23% of cases of acute necrotizing pancreatitis can end up in DPDS [1,2,4]. Disruption of the duct can lead to either ascites or become encysted to form a localized collection finally forming a walled-off necrosis.

Imaging Perspective

Patients with pancreatitis undergo serial CT imaging and diagnosis of DPDS is usually not detected on initial CT images unless the duct is visibly dilated. However, subsequent CECT can detect the condition with high sensitivity. MRCP is an excellent modality for diagnosis and confirmation can be done by ERCP.

Pancreatic necrosis, fluid collection adjacent to the main pancreatic duct, and viable pancreatic tissue distal to the disconnected duct segment are some of the chief imaging features [5].

A diagnostic criterion is used to diagnose DPDS confidently. The criterion consists of:

(a) necrosis of at least 2 cm of the pancreas;

(b) viable pancreatic tissue upstream (i.e., toward the pancreatic tail);

(c) extravasation of contrast material injected into the main pancreatic duct at pancreaticography;

(d) duct in the pancreatic tail segment should make an angle of 90° with the collection.

ERCP is the gold standard for the diagnosis of DPDS and shows leakage of contrast at the site of disruption.

Outcome/treatment

Conservative management is usually of no avail in the treatment of DPDS. Managing DPDS requires either redirection of secretions into the digestive tract or resection of the viable disconnected pancreatic segment. CT-guided percutaneous drainage of fluid surrounding the disrupted segment is the initial line of treatment. Placement of an indwelling stent between the two disrupted ends of the duct via ERCP minimizes the recurrence of pancreatic fluid collection [6,7]. Ultrasound-guided trans-gastric drainage of walled-off necrosis with pigtail stents is also done. Major surgical options include Roux-en-Y internal drainage (by pancreaticogastrostomy, pancreaticojejunostomy, or fistulotomy) and distal pancreatic splenectomy. However, these are reserved for cases that fail to respond to the first two options of treatment.

Teaching Points

Imaging plays a significant role in the diagnosis and follow-up of DPDS patients. The condition is a management challenge in many patients who develop the disease secondary to pancreatitis. Prompt diagnosis and multidisciplinary team effort are of utmost importance to prevent further complications.