Double plastic stent implantation for recurrent acute pancreatitis with incomplete pancreas divisum: a case report and literature review.

Pancreas divisum (PD) is a common pancreatic malformation caused by the failure of fusion between ventral and dorsal pancreatic ducts. There is a small branch of communication between the two systems in incomplete PD, and this variation has an incidence of 15%. A 43-year-old female patient presented to our department with recurrent abdominal pain. Magnetic resonance cholangiopancreatography (MRCP) showed that the ventral pancreatic duct was curved, with a local pouchlike dilatation. Endoscopic ultrasonography supported the diagnosis of incomplete PD and showed a thin branch of communication between ventral and dorsal pancreatic ducts. Endoscopic retrograde cholangiopancreatography (ERCP) and papillotomy of the minor papilla with double plastic stent implantation were performed. One pancreatic plastic stent was inserted across the minor and major papilla over the guide wire, creating a U-shape. The other wire-guided plastic stent was inserted through the minor papilla into the dorsal pancreatic duct. The pancreatic fluid drained smoothly after stent placement. During the 6-month follow-up, the patient remained well, without recurrence of pancreatitis.

Introduction

Pancreas divisum (PD) is a pancreatic malformation caused by the failure of fusion between ventral and dorsal pancreatic ducts. For incomplete PD, there is a small branch of communication between the two systems, with an incidence of 15%. Only 5% of patients with PD develop symptomatic disease, presenting as recurrent acute pancreatitis (RAP), chronic pancreatitis, and chronic abdominal pain. Currently, endoscopic retrograde cholangiopancreatography (ERCP), including endoscopic sphincterotomy (EST), is recommended for the treatment of incomplete PD. However, double plastic stent implantation, which combines a U-shaped stent with a dorsal pancreatic duct stent, has not been reported. We encountered a patient with incomplete PD presenting with RAP, and this article describes the ERCP procedure with double plastic stent implantation. This case report will add valuable knowledge to clinical practice.

Case presentation

A 43-year-old woman with RAP presented to our department with abdominal pain that persisted despite medical treatment. She was diagnosed as having acute pancreatitis 4 years earlier because of abdominal pain. The symptoms had worsened in the past 6 months, occurring every 2 to 3 weeks, without a definitive etiology, and symptoms improved after conservative treatment. Serological laboratory testing showed increased blood amylase and lipase concentrations, and abdominal computed tomography revealed acute pancreatitis. Magnetic resonance cholangiopancreatography (MRCP) showed that the ventral pancreatic duct was curved, with a local pouchlike dilatation (Figure 1). Endoscopic ultrasonography supported the diagnosis of incomplete PD and showed a thin branch of communication between ventral and dorsal pancreatic ducts (Figure 2). These examinations ruled out the possibility of intraductal papillary mucinous neoplasms and pancreatic tumor.

Figure 1.

Magnetic resonance cholangiopancreatography of a 43-year-old woman with recurrent acute pancreatitis showing the curved ventral pancreatic duct (yellow arrow) with a local pouchlike dilatation (blue arrow). The dorsal pancreatic duct (red arrow) is also seen.

Figure 2.

Endoscopic ultrasonography showing a thin branch (blue arrow) of communication between the ventral pancreatic duct (yellow arrow) and the dorsal pancreatic duct (red arrow).

With the patient’s medical history, serological indicators, and imaging results, we diagnosed RAP and incomplete PD. ERCP was performed, with papillotomy of the minor papilla and double plastic stent implantation. After cannulating the pancreatic duct through the major papilla (Figure 3a), we injected radiopaque contrast material. Pancreatography showed that the ventral pancreatic duct was short and tortuous, and that it communicated with the dorsal pancreatic duct via a thin duct (Figure 3b). Fortunately, the guide wire (Terumo, Tokyo, Japan) exited the minor papilla (Figure 3c). Minor papilla sphincterotomy was then performed with a sphincterotome, and a pancreatic plastic stent (9 cm, 5 F; Cook Medical, Winston-Salem, NC, USA) was inserted across the major and minor papillae over the guide wire, creating a U-shape (Figure 3d). The U-shaped stent served only as support for the pancreatic ducts and did not provide adequate drainage. For better drainage, stenting was followed by dorsal pancreatic duct cannulation via the minor papilla, with the intent of inserting a second stent (Figure 3e). After repeated pancreatic duct dilation failed with a dilation catheter, pancreatic duct dilation was performed successfully when an 8.5-F Soehendra stent retriever (Cook Medical) was rotated inward. Next, another wire-guided (Jagwire; Boston Scientific, Natick, MA, USA) pancreatic plastic stent (9 cm, 7 F; Cook Medical) was inserted through the minor papilla into the dorsal pancreatic duct (Figure 3f). The pancreatic fluid then drained smoothly. Postoperatively, the patient was treated medically with anti-cholinergic medications and pancreatic enzyme supplementation, and she improved symptomatically. During the 6-month follow-up, she remained well without recurrence of pancreatitis and abdominal pain. This report conforms to the CARE guidelines.

Figure 3.

Endoscopic retrograde cholangiopancreatography showing (a) cannulation of the pancreatic duct through the major papilla; (b) a short and tortuous ventral pancreatic duct (blue arrow) and communication with the dorsal pancreatic duct via a thin duct (red arrow); (c) the guide wire exiting the minor papilla; (d) inserting a pancreatic plastic stent across the major and minor papilla over the guide wire, creating a U-shape; (e) dorsal pancreatic duct cannulation via the minor papilla with the intention of inserting a second stent; (f) U-shaped stent (blue arrow) implantation combined with dorsal pancreatic duct stent implantation (red arrow).

Discussion

PD leads to the main dorsal pancreatic duct draining though the minor papilla and the small ventral pancreatic duct draining through the major papilla. MRCP is a non-invasive imaging modality that is considered the first choice in the diagnosis of PD. Secretin-enhanced MRCP has been suggested to enhance the detection of pancreatic malformations, including incomplete PD, with a sensitivity of 85% and specificity of 97%. ERCP is considered the gold-standard for the diagnosis of PD; however, ERCP is an invasive procedure involving radiation exposure and leads to a 10% to 15% complication rate, with an incidence of post-ERCP pancreatitis of up to 10%.[9-12] ERCP is used only for the diagnosis of uncertain cases and the treatment of symptomatic cases. Asymptomatic patients with PD do not require further diagnostic evaluation or treatment. In symptomatic patients with PD, conservative treatment, such as with anti-infection and anti-cholinergic medications, and pancreatic enzyme supplementation, should be considered. Therapeutic intervention is reserved for patients with recurrent attacks of acute pancreatitis or with clear imaging changes.

ERCP, with EST, with or without plastic stent implantation, is the first-choice therapeutic intervention in patients with symptomatic PD.[5,14-16] Plastic stent implantation in the pancreatic duct can prevent postoperative restenosis; however these stents should be replaced periodically. Zeng et al. described placing a U-shaped plastic stent in four patients with RAP and incomplete PD, with no complications related to the ERCP. Six months later, ERCP was performed again to remove the stent, and no patients experienced recurrence of pancreatitis and abdominal pain. Michailidis et al. confirmed that the efficacy of ERCP in PD is 67.5%. Our patient with incomplete PD presenting with RAP underwent ERCP with papillotomy of the minor papilla with double plastic stent implantation. A U-shaped stent was combined with a dorsal pancreatic duct stent. The difference between previous cases and our case is that, in our case, pancreatic duct dilation was performed with the Soehendra stent retriever rather than with a standard dilation catheter, which ensured a successful operation. The etiology in patients with PD presenting with RAP is poor drainage of pancreatic fluid because of stenosis of the minor papilla. Therapy with ERCP aims to enlarge the minor papilla and adequately drain the pancreatic fluid. Owing to proximal stenosis of the dorsal pancreatic duct, which was found during pancreatography through the minor papilla in our patient, only a U-shaped stent was sufficient to provide smooth drainage. The U-shaped stent served only as support for the pancreatic ducts. The dorsal pancreatic duct drains most of the pancreatic juice; therefore, stent placement in the dorsal pancreatic duct was necessary. To obtain long-term drainage, combining U-shaped stent implantation with dorsal pancreatic duct stent implantation can prevent postoperative stenosis and reduce the time between stent replacements.

To date, there are no reports of double plastic stent implantation in PD. This procedure is difficult to perform and requires time. Additionally, surgeons must have extensive experience performing endoscopic procedures. Surgery should be considered in cases of failure of endoscopic treatment in symptomatic patients or in cases of chronic pancreatitis and local complications, such as common bile duct stenosis or main pancreatic duct stenosis.[19,20] Life-long follow-up of patients with incomplete PD is mandatory.

Conclusion

Incomplete PD is a rare pancreatic malformation, and only a small number of patients develop symptoms. ERCP with EST is the first-line treatment for symptomatic patients with incomplete PD. The symptoms in our patient, who underwent ERCP with papillotomy of the minor papilla and double plastic stent implantation to improve pancreatic fluid drainage, improved significantly, and she remained well without recurrence of pancreatitis during the follow-up period. This procedure should be widely promoted and applied in clinical practice.