Journey through necrotizing pancreatitis

Case contributed by Vikas Shah
Diagnosis certain

Presentation

1 day history of severe abdominal pain. Tender all over abdomen. History of recent excess alcohol consumption.

Patient Data

Age: 50 years
Gender: Male

The pancreas is edematous and surrounded by a large volume of free fluid, in keeping with acute pancreatitis. There is some subtle reduction in density in the uncinate process, head, neck and proximal body of the pancreas, but this may be due to edema rather than necrosis at this early stage. The portal and splenic veins are patent. The liver has a diffusely reduced density in keeping with fat infiltration. No gallstones identified. The free fluid tracks in the retroperitoneum towards the pelvis. Appearances elsewhere unremarkable.

New bilateral pleural effusions with compressive lower lobe atelectasis. Moderate volume of ascites. Non-enhancement of uncinate process, head, neck and most of the body of the pancreas indicating developing necrosis. Heterogeneity in areas of fluid indicating necrosis rather than simple fluid (i.e. acute necrotic collection). Partially occlusive portal vein thrombus. Secondary thickening of splenic flexure of colon.

Progressive increase in volume of peripancreatic collection, with enhancing margin and heterogeneous content, indicating developing walled-off necrosis (a little earlier than the textbook 4 weeks). No propagation of portal vein thrombus. Reduction in pleural effusions, ongoing ascites.

Continuing maturation of large volume peripancreatic collections with enhancing margins and heterogeneous content indicating walled-off necrotic collection. More homogeneous looking fluid in the lower abdomen and pelvis, although with enhancing margins so considered to be complex, possibly infected.

A percutaneous drain was placed into the right lower quadrant to drain some of the fluid.

Drain has been removed. Reduction in volume of ascites and pelvic fluid and consequent reduction in AP diameter of abdomen. Reduction in volume of walled-off necrotic collection in upper abdomen. The hepatic flexure of the colon lies very close to the right lateral margin of the necrotic collection, and a couple of bubbles of gas are noted within the collection, suggesting the possibility of a fistula.

New pelvic drain in situ. Gas within walled off necrotic collection in upper abdomen - may be due to communication with drained pelvic collections, or further confirmation of fistula to bowel. Varices are developing near the splenic hilum.

A cystogastrostomy stent and pigtail drain were placed in order to reduce the volume of the walled-off necrotic collection.

The pigtail catheter is seen to traverse the stomach and collection, but the cystogastrostomy stent has been displaced and now lies in the distal part of the stomach, extending into an apparent fistula to the colon, and confirming the prior suspicion of a fistula.

Almost 200 days after the previous study, the peripancreatic collection has nearly dried up. The cystogastrostomy stent remains unchanged in position, bridging from the collection to the hepatic flexure of the colon, with in-drawing and tethering of bowel indicating scarring and fibrosis. Progressive splenic hilum varices formation due to previous portal vein thrombosis, although the portal vein now enhances more normally.

Case Discussion

There are several learning points from this longitudinal review of a patient's journey through necrotizing pancreatitis:

  • in the first few days, reduced density of the pancreas may be due to edema rather than reduced enhancement, and necrosis of the gland is more readily apparent after 7 days, so be cautious of specifying that acute pancreatitis is of the necrotic subtype too early in the course of the illness
  • the pancreatic and peripancreatic collections in necrotizing pancreatitis will be heterogeneous in density due to fat necrosis, and in the first 4 weeks are called acute necrotic collections
  • after the first 4 weeks, enhancing margins appear although still with heterogeneous content, and these areas are then called walled-off necrosis
  • this terminology has been developed by a multispecialty working group and is called the revised Atlanta classification
  • gas within walled-off necrosis may be due to infection, or fistula formation to adjacent small or large bowel
  • the cystogastrostomy stent migrated to the site of a suspected fistula between the walled-off necrosis and the large bowel, inadvertently but helpfully confirming the presence of a fistula
  • portal vein thrombosis is an early complication of acute pancreatitis, and variceal development may complicate subsequent interventions
  • patients with acute pancreatitis may have protracted inpatient stays with numerous imaging studies and interventional radiology procedures 

How to use cases

You can use Radiopaedia cases in a variety of ways to help you learn and teach.

Creating your own cases is easy.

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.