Pancreatic enlargement

Contrast-enhanced computed tomography (CT) is used to identify the cause of pancreatitis and confirm the diagnosis. Magnetic resonance imaging is used to grade the severity of AP and identify bile duct abnormalities not seen on CT. Ultrasonography is useful to determine pancreatic enlargement and peripancreatic fluid collections. 

B. L Samuels, S. 1. Ciilbet, J. Okamiua, et aL Early detection of chemotherapy-related pancreatic enlargement in children using abdominal sonography. A preliminary report Cancer 5 1515 (1976). 

A 54-year-old man developed abdominal pain from the beginning of interferon alfa treatment (260). Two weeks later his serum amylase and lipase peaked at about three times the upper hmit of normal. Careful radiological investigations ruled out pancreatic calcification and biliary or pancreatic hthiasis and showed only pancreatic enlargement. Complete improvement occurred after treatment withdrawal. As in the very few previous cases, there was no hypertriglyceridemia in this patient. 

In the study with adult dogs (Patten et al., 1971), pancreatic enlargement, when expressed per kg body weight, was found in a group fed raw soybean meal at 15% of the diet for 12 weeks. This enlargement was accompanied by significant increases in the con-... 

Examining the evidence as a whole, it does not appear justified to hypothesize a relationship between the occurrence of pancreatic enlargement with raw soybean feeding and pancreas size as a percent of body weight. This relationship may, in fact, exist, but to establish its validity more definitive studies will be needed. Until that time it is difficult to predict whether the human pancreas will enlarge with raw soybean feeding. 

Contrast agents can cause transitory enlargement of the pancreas (SEDA-11, 411). Oral and intravenous cholangiography have very rarely been reported to precipitate acute pancreatitis (158). 

Zollinger-Ellison syndrome A rare disorder where there is excessive gastric acid secretion due to high gastrin levels in the blood produced by an enlarged pancreas or pancreatic tumour. 

The nutritional importance of the protease inhibitors in major foods is reasonably clear. It is known that raw soybean flour inhibits growth in rats, chickens and some other monogastric animals (118) and death can result (119). It is also known that the presence of soybean inhibitor in the small intestine increases the secretion of a hormonal pancreozymic-like substance that markedly stimulates external secretion by the pancreas (120). The presence of active proteolytic enzyme inhibitors in the small intestine increases the production and secretion of proteolytic enzymes by the pancreas, presumably to compensate for their loss by complexation (121-123). This results in hyperplasia of some of the pancreatic cells and enlargement of the pancreas. 

Fig. 1.79. Acute pancreatitis. Diffuse acute pancreatitis in a 5-year-old girl with acquired immunodeficiency syndrome. Transverse US scan through the pancreas shows a globally enlarged pancreas with diffuse decreased echogenicity and irregulars borders (arrows). Note the poor definition of the splenic vein. Gallbladder (gb), left lobe of the liver (LL)...

There are differences between the pancreas in adults and children. In children, the pancreas will be considered enlarged if the pancreatic neck is bigger than... 

US may show an enlarged pancreatic head or a solid hand of pancreatic tissue around the (possibly dilated) duodenum with gastric dilatation (Gazelle etal. 1998). 

On CT, an annular pancreas (with or without pancreatitis) may be seen as enlargement of the pancreatic head, surrounding the second portion of the duodenum. Follow up CT may demonstrate calcifications limited to the annulus of the pancreas (Gazelle et al. 1998). 

The ductal abnormality in pancreas divisum may be diagnosed by MRCP often only after secretin stimulation (S-MRCP) (Fig. 4.16b,c). The duct of Santorini may be enlarged and the pancreas may demonstrate the characteristic features of pancreatitis. However, the detection of pancreas divisum at S-MRCP might be more difficult when stones or strictures are present in the ventral or dorsal pancreatic ducts (Manfredi et al. 2000). 

On US, the pancreas with CF is characteristically of an echogenic texture secondary to fatty infiltration (Fig. 4.17). An enlarged pancreas may be seen initially with a subsequent atrophy later in life. Pancreatic duct dilatation and calcifications may be seen. Small cysts (anechoic areas) without vascular communication can be identified. Although a hyperechogenic pancreas is very typical of CF, some other diseases such as Schwachman-Diamond syndrome (exocrine pancreas insufficiency associated with bone marrow dysfunction, cyclic neutropenia, metaphyseal diastasis and growth retardation), hemosiderosis, chronic pancreatitis, and administration of steroids may also reveal this feature (Feigelson et al. 2000). 

CT may demonstrate duct dilatation, focal areas oflow attenuation in the pancreatic parenchyma that correspond to fluid collections (King et al. 1995). Necrosis is recognized as a focal or diffuse area of non-enhancing pancreatic tissue. The pancreas can he enlarged or normal. Other findings include extra-pancreatic fluid collections located in the anterior pararenal space, lesser sac, lesser omentum, and transverse mesocolon. Peripancreatic fat stranding and pancreatic pseudocyst are sometimes encountered (Geier et al. 1990). 

Moderately important lesions include conditions that do not require immediate treatment but would likely require investigation, recognition or treatment at a later time. Examples of moderate importance include calculi of various organs, previously known abdominal aneurysms, adrenal masses, pancreatic pseudo cysts, indeterminate cysts of various organs, uterine enlargement in post-menopausal women, and coronary artery calcifications. 

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