A 41 year old male presented with diabetes, weight loss and possible pancreatitis from heavy alcohol use. Isolated agenesis of the dorsal pancreas was identified at the time of EUS. This may have resulted in more severe clinical manifestations than would be expected from the extent of pancreatic injury.
A 41 year old male with a history of heavy and persistent alcohol use presented with chronic diarrhea and weight loss. The patient was known to be diabetic for the previous 10 yrs.
His diabetes had been poorly controlled, in part due to the patient's poor social status. His hemoglobin A1C levels had been as high as 16.
His physical exam was unremarkable other than evidence of poor nutrition.
His alkaline phosphatase levels had been as high as 800 (nl < 125).
Colonoscopy was unremarkable, with no evidence of colitis or ileitis. Upper endoscopy revealed a gastropathy, but duodenal biopsies were normal, and stomach biopsies showed only nonspecific inflammation.
A CT was performed which showed “calcification and atrophy of the pancreas”.
EUS was performed. Video 1 shows landmarks seen during a normal EUS examination of the stomach. Pancreatic parenchyma was not identified along the splenic vein, near the left adrenal, or around the superior mesenteric artery. In Video 2, evaluation of the pancreatic head from the duodenum showed the common bile duct and main pancreatic duct at the level of the ampulla. The pancreatic head was hypermobile during insertion and withdrawl of the echoendoscope resulting in tortuosity of the common bile duct. The pancreatic ducts appeared to be in aberrant locations, but the parenchyma was relatively normal. These finding suggested agenesis of the dorsal pancreas.
The CT was re-reviewed in light of the EUS findings. Figure 1 shows a CT image of the distal splenic vein, and absence of pancreatic parenchyma. Figure 2 shows the pancreatic head and proximal aspect of the splenic vein, which confirmed the EUS findings.
The patients diarrhea, weight loss and elevated alkaline phosphatase appeared to respond to better diabetes control.
Complete agenesis of the dorsal pancreas is a rare congenital anomaly thought to be due to abnormal embryogenesis 1. The pancreas normally forms from two separate ventral and dorsal anlagen. During the 7th week of gestation the ventral bud rotates posteriorly to fuse with the dorsal bud and form the mature gland. The ventral bud gives rise to the major portion of the head and uncinate process, while the dorsal bud yields the upper part of the head, the body, and the tail of the pancreas. Agenesis of the dorsal pancreas may be partial or complete. In partial agenesis, the pancreas body is of varied size, a remnant of the accessory duct exists and the minor papilla is present. In complete agenesis, the neck, body and tail of the pancreas are absent, as are the accessory duct and the minor duodenal papilla 2.
Only 20 cases of complete agenesis of the dorsal pancreas have been reported in the literature since 19113. Diagnosis is often made upon investigation of acute abdominal pain. Imaging by US, CT, and MRI are suggestive 4,5 but are usually unable to confirm the detailed anatomy of agenesis of the dorsal pancreas 2,6. Diagnosis is generally made via ERCP, MRCP, and recently, EUS 7. It is critical to rule out pancreatic carcinoma with proximal atrophy, pancreas divisum, and pancreatic masses as these may resemble agenesis of the dorsal pancreas in imaging. Diabetes mellitus is often a secondary finding because islet cells are predominantly located in the body of the pancreas 2. A connection to pancreatitis has also been proposed. Potential mechanisms include Sphincter of Oddi dysfunction, compensatory enzyme hyper-secretion, hypertrophy of the ventral gland and higher pancreatic duct pressures8.
Clinical awareness of agenesis of the dorsal pancreas as a cause of abdominal pain, especially when associated with diabetes mellitus and pancreatitis can expand the differential diagnosis of abdominal pain and improve patient management.
ERCP: endoscopic retrograde cholangiopancreatography
MRCP: magnetic resonance cholangiopancreatography
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2. Schnedl WJ, Reisinger EC, Schreiber F, Pieber TR, Lipp RW, Krejs GJ (1995) Complete and partial agenesis of the dorsal pancreas within one family. Gastrointest Endosc 42:485-7
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4. Guclu M, Serin E, Ulucan S, Kul K, Ozer B, Gumurdulu Y, et al. (2004) Agenesis of the dorsal pancreas in a patient with recurrent acute pancreatitis: case report and review. Gastrointest Endosc 60(3):472-5
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7. Sempere L, Aparicio JR, Martinez J, Casellas JA, Madaria E, Perez-Mateo M (2006) Role of Endoscopic ultrasound in the diagnosis of agenesis of the dorsal pancreas. J Pancreas 7(4):411-6
8.Rakesh K, Choung OW, Reddy DN (2006) Agenesis of the dorsal pancreas (ADP) and pancreatitis- is there an associtation? Indian J Gastroenterol 25: 35-6