Editing Chronic pancreatitis (section)

== '''Aetiology''' - TIGAR-O ==

* Toxic-metabolic - generally synergistic
** Alcohol (seen in 70-80% of cases)
*** Five drinks a day for five years
*** But less than 5% of chronic drinkers develop it
*** Likely due to protein precipitation and formation of protein plugs and eventually stones. Also, ROS cause injury, and acetaldehyde causes direct acinar injury.
** Smoking
*** Seen in 90% of alcoholics with chronic pancreatitis
** Hypertriglyceridaemia
* Idiopathic (20%)
** Early-onset, late-onset, tropical
* Genetic
** Hereditary germline mutation PRSS1 gene - often early onset before age of 5, but almost always teenage years at latest
** SPINK-1
** CFTR
* Autoimmune pancreatitis (AIP)
** Type 1 - IgG4-related disease - seen in association with biliary strictures, retroperitoneal fibrosis, hilar lymphadenopathy, sclerosing sialadenitis, and interstitial nephrosis. Histology - lymphoplasmacytic sclerosing pancreatitis.
** Type 2 - limited to pancreas - not IgG4 - associated with IBD. "idiopathic duct-centric pancreatitis". Obliteration of epithelium in pancreatic duct.
** Treat with steroids. Often reversible. 
** 80% >50yo
* Recurrent/severe acute
** 10% of AP progresses to CP
* Obstructive
** Chronic obstruction of pancreatic duct - cystic dystrophy of duodenal wall, pancreas divisum, pancreatic neoplasm