An uncommon complication of acute pancreatitis: emphysematous pancreatitis

A 60-year-old woman presented to Emergency Department with epigastric pain, nausea, and vomiting.  Laboratory findings showed raised inflammatory markers and high levels of serum amylase (865 U/L) and lipase (1250 U/L). The patient was hospitalized for treatment but showed no improvement, so underwent CT examination 5 days later.

Contrast-enhanced abdominal CT exam revealed a large amount of gas replacing the pancreatic parenchyma and extensive inflammatory changes involving the surrounding fat (Fig.1a and 1b), compatible with necrotizing pancreatitis complicated with emphysema.

CT showed no cholelithiasis and the patient had no history of alcohol consumption.

The patient underwent another CT examination 12 days later showing formation of a fluid collection with gas, compatible with an acute necrotic collection (Fig.2). The collection was percutaneous drained under CT guidance; however, the drainage was incomplete, and the patient subsequently underwent pancreatic necrosectomy. The patient was discharged 15 days later.

Emphysematous pancreatitis is an uncommon and serious complication of severe acute pancreatitis, in which pancreatic parenchyma necrosis occurs and the pancreas is replaced by gas. As in other emphysematous infections, patients that develop this entity usually have other comorbidities such as poorly controlled diabetes, heart failure, chronic renal failure or others forms of immunocompromise [1].

The most common organisms associated with emphysematous pancreatitis are gram-negative anaerobes, with Escherichia coli being the most common. The pathways of spread of these bowel gas-forming bacteria to the pancreas includes hematogenous, lymphatic, direct through the ampulla of Vater or transmural through the adjacent transverse colon [2].

Acute pancreatitis usually manifests as abdominal pain, nausea, and vomiting and elevated pancreatic enzymes. Uninterrupted or recurrent pain, a second peak in pancreatic enzyme levels, worsening organ dysfunction, or sepsis are suspicious of complications and should lead to imaging evaluation, namely by contrast-enhanced CT [3].

The key radiological finding associated with emphysematous pancreatitis is the presence of retropneumoperitoneum. The abdominal x-ray study may show mottled gas pattern in epigastrium, but this is a relatively non-specific finding. CT is the modality of choice for detecting pancreatic necrosis accompanied by intra- and/or peri-pancreatic gas as well as evaluating its extent and location. Other findings that can be found are the presence of gas in portal venous system and the presence of fluid collections. However, the presence of intraparenchymal gas is not diagnostic of emphysematous pancreatitis. There are several other causes of air in the pancreas, like enteropancreatic fistula, surgical instrumentation, patent ampulla of Vater and penetrating duodenal ulcers [2].

Effective treatment requires rapid treatment of the infection and control of septic shock [1]. The treatment options are conservative management based on antibiotic coverage and supportive care, percutaneous or endoscopic drainage, and surgical debridement. The prognosis of emphysematous pancreatitis is particularly poor, with high-level mortality despite adequate treatment [4].

Take Home Message: In patients with acute pancreatitis, an early diagnosis of intraparenchymal gas is crucial to the rapid management of this high-rate mortality entity.

Written informed patient consent for publication has been obtained.