Etiopathogenesis of primary sclerosing cholangitis

Table 5 Comparison of PSC and AIP-SC

	PSC	AIP-SC
Gender	M:F = 2:1	Probably some male predominance[818587]
Clinical presentation	Usually insidious. Sometimes with obstructive jaundice secondary to cholangiocarcinoma.	Mild abdo/Back pain
		Sometimes with short history of obstructive jaundice due to CBD stricture
Associated inflammatory bowel disease	Yes	No
Cholangiographic findings	Diffuse changes throughout intra- and extrahepatic bile ducts. Abnormalities in pancreatic duct common.	Pancreatic duct strictures or narrowing. Often stricture of distal 1/3 of common bile duct. Intrahepatic duct changes less common.
Blood chemistry data	Often cholestatic but bilirubin usually near normal.	May be cholestatic. Bilirubin often high
Autoantibodies	Atypical pANCA plus range of others	Antibodies to carbonic anhydrase II plus range of others[808184]
Immunoglobulins	IgG4 levels normal	IgG4 levels usually elevated[82]
Histology	Absence of plasma cells positive for IgG4 on immunostaining	IgG4 positive plasma cells present in bile ducts and portal tracts[79]
Liver biopsy staging	Range of Ludwig staging including higher stages eg III or IV	Ludwig staging usually only I or II[86]
Treatment	Ursodeoxycholic acid ± biliary drainage for dominant strictures	Systemic steroid therapy usually leads to complete resolution of symptoms and signs of disease. Occasionally patients relapse and require longer courses of steroids