Everything Fun Will Kill You (Acute Pancreatitis)

The diagnostic criteria for pancreatitis was established by the Atlanta Criteria (Banks 2012) in 1992 and revised in 2012. To be diagnosed with pancreatitis, one must have two of the following three features: 

(1) abdominal pain consistent with acute pancreatitis (acute onset of a persistent, severe, epigastric pain, often radiating to the back)

(2) serum lipase elevation (or amylase elevation) at least three times greater than the upper limit of normal

(3) characteristic findings of acute pancreatitis on contrast-enhanced CT (or less commonly MRI or transabdominal ultrasonography)

Pancreatitis occurs when the exocrine pancreas, which secretes enzymes such as trypsinogen are prematurely activated. This typically occurs secondary to some inciting event leading to acute inflammation and autodigestion of the pancreas. Typical causes of pancreatitis are (Quinlan 2014):

Choledocholithiasis (40%)
Chronic alcohol use or abuse (35%)
Endoscopic retrograde cholangiopancreatography (4%)
Medication use (2%)
Abdominal trauma (1.5%)

According to the Rosens Emergency Medicine, choledocholithiasis is usually the cause of pancreatitis in women, while alcohol use is usually the cause in men. Remember that a sonogram may not be enough to rule out choledocholithiasis – the smaller the stone, the more likely it is to cause pancreatitis, but the less likely it is to be picked up by ultrasonography.

Once the diagnosis is made, acute pancreatitis can be divided into two types: interstitial edematous pancreatitis and necrotising pancreatitis.

Interstitial Edematous: Majority of patients with acute pancreatitis present with this milder form. Here, the inflammation causes edema of the organ, and symptoms typically improve within 7 days.

Images courtesy of Bronson, Radiopaedia.org 2018

Necrotising Pancreatitis: Approximately 5-10% of the population presenting with pancreatitis will develop necrosis. This is not typically an early sequelae of pancreatitis, so it is important to ascertain from patients when their symptoms started. Necrotising pancreatitis can involve both the pancreas and peri-pancreatic tissues. The necrosis may remain sterile, liquefy, or become infected. Infection is associated with increased morbidity.

Images courtesy of Bronson, Radiopaedia.org 2018

For some, the default management pathway for severe abdominal pain and any tenderness will be to image the patient. The discerning second year that you are, however, would be aware that early imaging in pancreatitis is unnecessary, especially during the first few days. Early CT does not accurately identify the degree of pancreatic necrosis and may underestimating its extent. Early imaging is only recommended when:

(1) there is diagnostic uncertainty — for example atypical abdominal pain — or normal pancreatic enzyme levels in the setting of high clinical suspicion

(2) other suspected intra-abdominal pathology is possible — for example, bowel obstruction or aortic aneurysm

(3) patients fail to respond to appropriate therapy after at least 48 hours

The CT identification  of complications is best done at least 3 to 7 days after presentation (Bharwani 2011).

Pancreatitis can vary from a rather mild disease to one with a mortality of 30%. It can be difficult when assessing the patient in front of you at time point “0” to determine which course the disease will follow. The revised Atlanta Criteria placed acute pancreatitis presentations in 3 categories (Rosens 2018):
.

• Mild acute pancreatitis
  • No organ failure
  • No local or systemic complications
• Moderately severe acute pancreatitis
  • Organ failure that resolves within 48 h (transient organ failure) and/or
  • Local or systemic complications without persistent organ failure
• Severe acute pancreatitis
  • Persistent organ failure (>48 h)
    • Single organ failure
    • Multiple organ failure

Additionally several scoring systems have been devised to assess the severity and likelihood of morbidity and mortality of pancreatitis. Many of them, however, such as the Ranson’s criteria,  are quite cumbersome and involve data points at 48 hours after initial presentation.

Treatment of pancreatitis is mainly supportive. Managing symptoms with antiemetics, pain control and fluid resuscitation are the mainstays. Data (Rosens 2018) has indicated that patients should no longer be made NPO, as it leads to increased gastrointestinal mucosal atrophy and amplifies bacterial overgrowth and translocation of gut bacteria. In mild cases patients should be encouraged to eat as early as tolerated. In severe cases, NG tube feeds can be considered.

There is no role for prophylactic antibiotics in pancreatitis (Tanner 2013).
.

Given the variable course of pancreatitis, even in patients with mild pancreatitis, further observation should be considered until symptoms begin to resolve. In patients with moderately-severe or severe pancreatitis according to the Atlanta classification, admission to an ICU should be considered.