Pancreas divisum is a common congenital anomaly (an anomaly that is present at birth) of the pancreatic duct(s).
The pancreas is a deep-seated organ located behind the stomach. One of its functions is to produce enzymes that are important for the digestion of food in the intestine.
The digestive enzymes, in the form of digestive juice, drain from the pancreas via the pancreatic duct into the duodenum (the uppermost portion of the small intestine) where they aid in digesting food.
Pancreas divisum is the most common birth defect of the pancreas. The human embryo starts life with a pancreas that is in two parts, each with its own duct; the ventral duct and the dorsal duct.
The two parts of the pancreas fuse during development.
In more than 90% of the embryos, the dorsal and the ventral ducts also will fuse to form one main pancreatic duct.
The main pancreatic duct will join the common bile duct (the duct that drains bile from the gallbladder and the liver) to form a common bile and pancreatic duct that drains into the duodenum through the major papilla.
In approximately 10% of embryos, the dorsal and the ventral ducts fail to fuse. Failure of the ventral and the dorsal pancreatic ducts to fuse is called pancreas divisum (because the pancreas is drained by two ducts).
In pancreas divisum, the ventral duct drains into the major papilla, while the dorsal duct drains into a separate minor papilla.
If a pancreatic duct becomes blocked, swelling and tissue damage (pancreatitis) may develop.
Most people with a pancreas divisum are asymptomatic but it is more frequently found in patients with chronic abdominal pain and idiopathic pancreatitis than in the general population 4.
It results from failure of fusion of dorsal and ventral pancreatic anlages. As a result, the dorsal pancreatic duct drains most of the pancreatic glandular parenchyma via the minor papilla.
Although controversial, this variant is considered as a cause of pancreatitis.
Pancreatic divisum can result in a santorinicoele, which is a cystic dilatation of the distal dorsal duct, immediately proximal to the minor papilla.
Three subtypes are known:
- type 1 (classic): no connection at all; occurs in the majority of cases: 70%
- type 2 (absent ventral duct): minor papilla drain all of pancreas while major papilla drains bile duct; 20-25%
- type 3 (functional): filamentous or inadequate connection between dorsal and ventral ducts: 5-6%
Most individuals born with pancreas divisum experience no symptoms throughout life, will remain undiagnosed, and will not require treatment.
A small number of patients with pancreas divisum will experience repeated episodes of pancreatitis. Some patients with pancreas divisum may develop chronic abdominal pain without pancreatitis.
- Abdominal pain, most often in the mid-abdomen, that may be felt in the back
- Abdominal swelling (distention)
- Nausea or vomiting
Doctors are not certain how pancreas divisum causes abdominal pain and pancreatitis. One theory is that the minor papilla is too narrow to adequately drain the digestive juices in the dorsal portion of the pancreas.
The backup of the digestive juices elevates the pressure in the minor duct that causes abdominal pain and pancreatitis.
Others believe that there must be other factors above and beyond pancreas divisum that predispose a certain population of patients to develop pancreatitis.
Research continues in order to determine the exact relationship
Exams and Tests
- Abdominal ultrasound
- Abdominal CT scan
- Amylase and lipase blood test
- Endoscopic retrograde cholangiopancreatography (ERCP)
- Magnetic resonance cholangiopancreatography (MRCP)
- Endoscopic ultrasound (EUS)
How is pancreas divisum diagnosed?
The most accurate test to diagnose pancreas divisum is ERCP (endoscopic retrograde cholangio-pancreatography), which can demonstrate the presence of two separately draining pancreatic ducts.
However, ERCP itself sometimes can cause attacks of pancreatitis.
Other tests that can help diagnose pancreas divisum without the risk of causing pancreatitis include endoscopic ultrasound (EUS), and MRI (magnetic resonance imaging).
The following treatments may be needed if you have symptoms of the condition, or if pancreatitis keeps returning:
- ERCP with a cut to enlarge the opening where the pancreatic duct drains
- Placement of a stent to prevent the duct from getting blocked
- You may need surgery if these treatments do not work.
Most of the time, the outcome is good.
The main complication of pancreas divisum is pancreatitis.
When to Contact a Medical Professional
Call for an appointment with your health care provider if you develop symptoms of this disorder.