What are the two appearances of acute pancreatitis (natural history)?

2 phases: interstitial and necrotizing. Interstitial: mild case involving 2/3 of pancreatitis, severity of the case depends on extra-pancreatic organs involved, presents with the normal signs of inflammation (fever, tachycardia, hypotension, respiratory distress, leukocytosis (SIRS -system inflammatory response syndrome) Necrotizing: severe, in 1/3 of cases, lasting weeks to months, mortality due to infection of necrosis and organ failure