Teaching Case

The patient presented to emergency with strong abdominal pain, vomiting and dyspnoea. Acute abdomen was suspected so computed tomography (CT) was requested.

In abdominal CT without contrast media (CM) a lot of free bilateral pleural and peritoneal fluid was found. Oedema and calcifications of pancreas were evident. As you can see in figs 1a, 1b, 1c, there were inflammatory changes of the peripancreatic area. After CM administration, in arterial phase around left gastric artery there was an aeneurysm-like enhanced formation which persisted even in the late phases of examination (Figs 2a, 2b, 2c, 2d). Pseudoaeneurysm of left gastric artery cause of acute exacerbation of chronic pancreatitis was the main complication finding (Figs 3a, 3b, 3c, 3d, 3e).

Chronic pancreatitis is a progressive fibroinflammatory disorder characterised by intermittent or continuous abdominal or back pain (or both) due to persistence of structural damage after the primary cause has been eliminated. This damage results in loss of pancreatic parenchyma, functional insufficiency (endocrine and exocrine), and complications such as biliary stricture, pseudocyst, and pseudoaeneurysm. Three principal forms of chronic pancreatitis are currently recognised:
1-Calcifying chronic pancreatitis. Pathologically, this form is characterised by acinar destruction and perilobular fibrosis with acute and chronic inflammatory cells. It presents with recurrent bouts of abdominal pain and eventual development of intraductal calculi in a large proportion of cases. Causative factors include alcohol, tobacco use, hereditary senile etc.
2-Obstructive chronic pancreatitis. In this form, persistent obstruction of the pancreatic duct due to tumour or postinflammatory ductal stricture leads to atrophy of the upstream pancreas. Though often painless, it occasionally presents with clinically acute pancreatitis. Intraductal calculi are generally not seen.
3-Autoimmune pancreatitis. This is a chronic systemic lymphoplasmacytic inflammatory process. [1, 2, 3, 4]
Irregular ductal dilation and strictures, parenchymal atrophy, and pancreatic calcifications are typical CT manifestations of chronic pancreatitis. Pancreatic ductal dilation, though a frequent manifestation of chronic pancreatitis, is not specific; it can also be seen with pancreatic and ampullary carcinomas. [5, 6] In pancreatitis the dilated pancreatic duct is associated with irregularity owing to dilated side branches. Focal or diffuse pancreatic atrophy, a secondary manifestation of chronic pancreatitis, may be underestimated by CT because interlobular and periductal fibrous connective tissue and chronic inflammatory infiltrate can replace functioning parenchyma, resulting in little or no loss of total pancreatic mass. [7] Pancreatic calculi or calcifications are the most specific CT manifestations of chronic pancreatitis and are not found in association with neoplastic obstruction. Pancreatic calcifications are almost always within the ductal system, although this intraductal location may not be evident on CT, they are detectable with ERCP. [6]
Patients with chronic pancreatitis may occasionally present with acute symptoms and elevated serum amylase level. Clinical presentation is often mild to moderate and stigmata of chronic pancreatitis are detected on CT examination. There is usually evidence of parenchymal atrophy, dilatation of the pancreatic duct (finding absent in acute pancreatitis), intraductal calcifications and mild peripancreatic inflammatory reaction and/or small fluid collections. Associated pseudoaeneurysms or pancreatic abscesses may be present. The intrinsic pancreatic morphologic changes are permanent while acute CT changes and clinical symptoms usually resolve with conservative therapy. [8]