Pancreatitis, Acute

Diagnosis of Acute Pancreatitis:
· Acute inflammation in the pancreas/peripancreatic tissues, thought to be due to unregulated activation of trypsin (+inflammatory cytokines)
· Epidemiology: incidence is increasing, approx 40/100,000 adults in the western countries; more common in men, mortality rate ~ 7%
· Clinical presentation is sudden onset of epigastric pain, often radiating to the back; can be accompanied by N, V, fever, tachycardia
· Laboratory testing will show elevations in serum lipase and amylase; degree of elevation does not correlate w/ severity of disease; lipase is more specific than amylase
· Contrast-enhanced CT scan is the most specific diagnostic test, and can help grade severity of disease
· You do NOT need to get a CT in every pt with pancreatitis—the AGA recommends obtaining a CT scan in pts who present with severe pancreatitis based on clinical findings/APACHE II score; additionally as pancreatic necrosis can take up to 48 hrs to develop, the AGA recommends obtaining a CT after 72 hours of illness in pts with predicted severe disease and those with evidence of organ failure

Adjunctive lab tests can be ordered; AGA recommends considering a CRP in addition to clinical judgment and the APACHE II score. (CRP >150 mg/L predicts severe disease)

Etiology of Acute Pancreatitis:
· 80% of cases in adults are due to alcohol or gallstones
· 10% are due to other causes: drugs (azathioprine, sulfa drugs, DDIs), metabolic (hypertriglyceridemia, hypercalcemia), infectious (viral, parasites), vascular (ischemic, obstructive (malignancy, pancreas divisum etc.)
· 10% of cases are idiopathic
· Given the high rate of gallstone pancreatitis, and the high rate of recurrence (up to 50% of pts who do not have cholecystectomy for gallstone pancreatitis will have a recurrence within next 100 days), AGA recommends abd US in all pts with an initial presentation of pancreatitis
· Increased LFTs, particularly ALT may suggest gallstone pancreatitis

Prognostic Scoring in Acute Pancreatitis:
· Several scoring systems exist: Ranson’s score, SOFA (sequential organ failure assessment), Glasgow Score, APACHE II. All of these scores involve a combination of clinical and laboratory assessments, and some take 48 hrs to complete.
· APACHE II is most complicated score, but recommended by AGA for initial assessment
· Ranson’s score is used often, but metanalyses have shown it to have poor predictive value
· CT severity index (Balthazar score) is most helpful when pancreatitis is severe: the score is based upon the degree of necrosis, inflammation, and the fluid collections around the pancreas. The score has been validated and mortality is closely associated with degree of pancreatic necrosis
· Criteria for severe acute pancreatitis include: a Ranson's score of 3 or more and/or an APACHE II score of 8 or more within the first 48 hours, evidence of organ failure, and/or local complications (pancreatic necrosis, abscess, or pseudocyst)

Treatment of pancreatitis:
· Early treatment is supportive, consisting of IVF resuscitation (250-300cc/hr), pain control, antiemetics and NPO status
· Goal is treatment of underlying etiology, if possible (evaluation for gallstones, cholecystecomy +/- ERCP if evidence of cholangitis; removal of possible offending agents, ie. etoh, drugs etc.)
· If pt is not responding to supportive measures, further evaluation with contrast enhanced CT should be obtained, for evaluation of possible necrosis or focal fluid collections
· Enteral feeding? Several meta-analyses have found that enteral feeding (c/w parenteral feeding) in severe pancreatitis decrease infectious complications and mortality benefit in certain patient groups. Enteral feeds should be considered in severe cases of pancreatitis, when PO intake cannot be advanced within 2-3 days
· Prophylactic abx? The AGA does not recommend prophylactic abx unless there is evidence of >30% pancreatic necrosis. Also significany concern that prophylactic abx can increase the selection of resistant organisms and fungal infxns
· If abx are indicated for severe, necrotic pancreatitis, best choice is imipenem or meropenem

Good review of acute pancreatitis in Lancet, 2008:
http://sfx.stanford.edu.laneproxy.stanford.edu/local?sid=Entrez:PubMed&id=pmid:18191686

(Victoria Kelly MD, 10/21/10)