Elevation of serum amylase. Opie s hypthesis - blockage of the Ampulla of Vater causing bile reflux and pancreatitis. An alternative theory for gallstone pancreatitis is that there is blockage of the pancreatic duct without bile reflux.
Interstitial oedema impairs blood flow .Activation of the kallikrein and kinin system occurs.
Systemic features are due to the release of toxic enymes, cytokines with explosive activation of the systemic inflammatory response. Pancreas is enlarged, oedematous and haemorrhagic. It may become necrotic. Calcium salts deposits form all over the abdomen. Necrosis may involve subcutaneous tissue-Grey Turners sign.