Identification and management of pancreas divisum

ABSTRACT

Introduction: Pancreas divisum is the most common congenital malformation of the pancreas with the majority asymptomatic. The etiological role, pathogenesis, clinical significance and management of pancreas divisum in pancreatic disease has not been clearly defined and our understanding is yet to be fully elucidated.

Areas covered: This review describes the role of pancreas divisum in the development of pancreatic disease and the ambiguity related to it. In our attempt to offer clarity, a comprehensive search on PubMed, Ovid, Embase and Cochrane Library from inception to May 2019 was undertaken using key words “pancreas divisum”, “idiopathic recurrent acute pancreatitis” and “chronic pancreatitis”.

Expert opinion: Current research fails to define a clear association between pancreas divisum and pancreatic disease. Though debatable, several studies do suggest a pathological role of pancreas divisum in pancreatic disease and a benefit of minor papilla therapy in the setting of acute recurrent pancreatitis. Surgical and endoscopic therapeutic modalities have not been directly compared. With the current data available, it would be imprudent to advise a definitive line of management for pancreatic disease associated with pancreas divisum and should involve a comprehensive discussion with the individual patient to define expectations before embarking on any medical and/or interventional therapy.

KEYWORDS:

• Recurrent acute pancreatitis
• chronic pancreatitis
• idiopathic pancreatitis
• pancreas divisum
• dorsal duct syndrome
• endoscopic retrograde cholangiopancreatography
• magnetic resonance cholangiopancreatography

Reviewer disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Article highlights

• Pancreas divisum is the most common congenital malformation of the pancreas and occurs due to a failure of fusion of the ductal systems of the dorsal and ventral pancreatic buds in the seventh week of intra-uterine life. This leads to a dominant dorsal pancreatic duct draining through the minor papilla and a small ventral pancreatic duct draining through the major papilla. The prevalence in the western population is about 10% with a lower frequency of 1-2% in Asians and Africans.

• More than 95% of patients with pancreas divisum lack pancreatic symptoms, with the anomaly found incidentally on abdominal imaging (e.g., Computerized Tomography, Magnetic Resonance Cholangiopancreatography) performed for unrelated symptoms and indications.

• The etiological role and clinical significance of pancreas divisum in pancreatic disease such as pancreatic-type abdominal pain (intermittent or chronic), acute pancreatitis or chronic pancreatitis has been suggested based on its increased incidence in the IRAP population, pathologic studies suggesting pancreatic disease limited to the dorsal pancreas and improvement in outcome following minor papilla interventions. However, this remains debatable with no clear causality identified.

• It has been demonstrated to predispose to pancreatic disease in association with other factors such has genetic mutations of SPINK-1, CFTR, CTRC and therefore should be checked in pertinent clinical situations. It has also been shown to decrease the threshold for other known causes of pancreatic disease such as alcohol, medications, toxins, trauma.

• Secretin augmented Magnetic Resonance Cholangiopancreatography is the non-invasive imaging modality of choice for diagnosing pancreas divisum.

• The pathogenesis of pancreatic disease in pancreas divisum is not clearly defined but is believed to be due to an imbalance between the drainage of a larger and longer dominant dorsal pancreatic duct opening through a relatively smaller or stenotic minor papilla, causing inadequate drainage of pancreatic secretions and transient obstruction of flow. The resultant increase in intraductal pressure and distention of the dorsal duct may then lead to abdominal pain and pancreatitis.

• No further pancreatic evaluation or therapy is needed or recommended in patients with asymptomatic pancreas divisum. In patients deemed to be symptomatic from pancreas divisum, after a comprehensive evaluation for causes of pancreatic disease is completed, therapy is offered for patients suffering from recurrent attacks of acute pancreatitis and can be considered for a severe attack of acute pancreatitis and its complications, chronic pancreatitis and its associated complications and chronic pancreatic-type abdominal pain causing significant functional impairment and debility. It is important not to ignore the standard management principles of acute and chronic pancreatitis.

• In patients with mild or infrequent symptoms of pancreatic-type abdominal pain, conservative management is pursued and directed towards symptom control.

• Endoscopic Retrograde Cholangiopancreatography with minor papilla endotherapy is the current first line of therapy. Minor papilla sphincterotomy is the predominant intervention due to the adverse event profile of balloon dilation of the minor papilla and long-term pancreatic stents. The procedure-related risk profile is similar to that of major papilla pancreatic sphincterotomy in high-risk patients.

• Minor papilla surgical therapy has a comparable outcome with endotherapy but due to a less favorable adverse event profile is currently reserved for patients who fail endoscopic intervention. The choice of endoscopic or surgical therapy also depends on patient profile and preference as well as local institutional expertise.

• The response to either endoscopic or surgical therapy is variable with maximal benefit seen in patients with recurrent acute pancreatitis, less with chronic pancreatitis and least with chronic pancreatic-type abdominal pain.

• Data supporting either endoscopic or surgical therapy are of low quality as the studies are predominantly retrospective with a relatively short follow-up period.

• In patients who fail minor papilla therapy, management is directed towards symptom control, with options including periods of pancreas rest with post-ligament of Treitz enteral feeding, celiac plexus block, somatostatin analogues and placement of an intrathecal pain pump.

• Additional surgical options including a pancreatojejunostomy (Puestow or Frey procedure) or a total pancreatectomy with auto- islet cell transplantation may be an option for a subset of patients.

Additional information

Funding

This paper is not funded.