Teaching Case

A 68-year-old man without known allergies. No DM. No arterial hypertension. Non-smoker. Ischemic stroke 11 years ago. Peptic oesophagitis. No surgical history of interest. In the last year an ultrasound and gastroscopy was performed without pathological findings. The patient came to the emergency room with diffuse abdominal pain. At admission in Emergengy room, he had no fever but he had very important laboratory abnormalities: Leukocytosis (21000), pancreatic amylase 2590 U/L (normal 13-53 U/L), RCP 23ng/mL.

Pancreas presents irregular and not well-defined borders with adjacent mesenteric fat stranding with fluid collections (inflammatory changes), with gas presence at pancreatic regions, and also may be present in the minor sac, hepatic hilium, hepatic fissure, pararenal spaces, root of mesentery, etc.
Multiple foci of gas in the necrotic pancreas with a large collection, containing both fluid and gas around the body of the pancreas (inside pancreatic cell).

Background: Emphysematous pancreatitis is a rare but serious complication of acute pancreatitis. Few cases have been described in the literature. It is characterized by total or subtotal destruction of the pancreas, with occupation with pancreatic cell gas. The evolution towards this type of pancreatitis may be suspected if the patient has fever and noticeable abdominal guarding in the course of acute pancreatitis [7].

Gas-forming organisms from the bowel may enter the pancreas to cause emphysematous pancreatitis [2]. Besides infection with gas-forming bacteria such as Escherichia coli, Clostridium, Staphylococcus, Streptococcus, Klebsiella, Candida and Pseudomonas, other possible sources include bland tissue infarction with necrosis, enteric fistula formation, and reflux from the adjacent hollow viscus [7]. Other clinical factors that contribute to the increased production or slowed removal of gas include a depressed cell-mediated immune response, local tissue necrosis and presence of atherosclerosis [3].

Clinical perspective: The initial clinical manifestation may be insidious, but rapid progression to sepsis will occur in the absence of early therapeutic intervention. Frequent symptoms: The patient may present epigastric and progressive abdominal pain, fullness and amylase levels >500 U/L. Hypotension, anuria and jaundice may be possible [6].

Imaging perspective: The abdominal x-ray study may show mottled air pattern in epigastrium. At US we can see multiple echogenic images with reverberating acoustic posterior shadow [8].
The diagnostic technique of choice is MDCT (CT is both highly sensitive and specific in the detection of abnormal gas) with which we can see gas collection drawing the outline of pancreatic parenchyma partially or completely [4]. The gas occupies necrotic areas.
Retropneumoperitoneum is the key factor in the diagnosis of this entity.
Also we can find air in the portal venous system and the presence of liquid collections [8]. In our case, in samples taken during surgery, bacteriology studies showed an infection by Clostridium perfringens and Klebsiella oxytoca (gram negative flora), so the cause in this case is a bacteriology infection of the pancreas.

Outcome: Management of emphysematous pancreatitis consists of fluid resuscitation and anti-microbial therapy to control septic shock [6]. The prognosis for emphysematous pancreatitis is grave, and successful treatment requires aggressive management of the infection with systemic antimicrobial therapy and control of septic shock. Early surgical debridement is usually performed, and recovery is typically prolonged. [1, 3, 6, 7].

Teaching points: The presence of gas in the pancreatic bed doesn't necessarily means abscess, it could suggest also grave emphysematous pancreatitis. The diagnosis of emphysematous pancreatitis involves a grim prognosis, with high mortality. MDCT is the diagnostic technique of choice and crucial for early treatment [1, 3, 4, 5, 8].