Patients may come to attention only because of persistent elevation of serum alkaline phosphatase, particularly in those with ulcerative colitis who are being routinely screened. Alternatively, progressive fatigue, pruritus, and jaundice may develop. Acute bouts of ascending cholangitis may also signal the presence or progression of PSC. Chronic pancreatitis and chronic cholecystitis due to involvement of the pancreatic ducts and gallbladder are also seen. In some patients, sclerosing cholangitis is associated with autoimmune pancreatitis. In such cases PSC may be one manifestation of IgG4 related chronic disease (Chapter 5).
PSC follows a protracted course of 5 to 17 years, and severely afflicted patients have symptoms typical of chronic cholestatic liver disease, including steatorrhea. Unlike with PBC, there is no satisfactory medical treatment. A variety of immunosuppressive agents have been tried, but none has been proven to alter the disease course. Endoscopic dilation with sphincterotomy or stenting is used to relieve obstruction. Liver transplantation is the only definitive treatment for individuals with end-stage liver disease.
Cholestasis occurswithimpairedexcretionofbile,leadingtojaundiceandaccumulationofbilepigmentinthehepaticparenchyma.Causesincludemechanicalorinflammatoryobstructionordestructionofthebileductsormetabolicdefectsinhepatocytebilesecretion.
Large bile duct obstruction ismostcommonlyassociatedwithgallstonesandmalignanciesinvolvingtheheadofthepancreas.Chronicobstructioncanleadtocirrhosis.
Neonatal cholestasis isnotaspecificentity;itisvariouslyassociatedwithcholangiopathiessuchasbiliary atresia andavarietyofdisorderscausingconjugatedhyperbilirubinemiaintheneonate,collectivelyreferredtoasneonatal hepatitis.
Primary biliary cholangitis isanautoimmunediseasewithprogressive,inflammatory,oftengranulomatous,destructionof
Fig. 16.29 Primarysclerosingcholangitis.Abileductundergoingdegenera-tionisentrappedinadense,“onion-skin”concentricscar.
http://ebooksmedicine.net smalltomediumintrahepaticbileducts.Itmostoftenoccursinmiddle-agewomenandisassociatedwithanti-mitochondrialantibodiesandoftenwithotherautoimmunediseases,suchasSjögrensyndromeandHashimotothyroiditis.
•Primary sclerosing cholangitis isanautoimmunediseasewithprogressiveinflammatoryandsclerosingdestructionofintrahepaticandextrahepaticbileductsofallsizes.Diagnosisismadebyradiologicimagingofthebiliarytree.Itmostoftenoccursinyoungermenandhasastrongassociationwithinflammatoryboweldisease,particularlyulcerativecolitis.
Hepatic circulatory disorders can be grouped according to whether the disorder leads to abnormalities in the inflow, flow-through, or outflow of blood (
Fig. 16.30
Liver infarcts are rare, thanks to the double blood supply to the liver. Nonetheless, thrombosis or obstruction of an intrahepatic branch of the hepatic artery by embolism (
Fig. 16.31 ), neoplasia, or an inflammatory process such as polyarteritis nodosa (Chapter 10) may produce an infarct, which may either be pale or hemorrhagic if suffused with blood from the portal circulation. Blockage of the main hepatic artery may not produce ischemic necrosis of the organ, particularly if the liver is otherwise normal, as retrograde arterial flow through accessory vessels and the portal venous supply is usually sufficient to sustain the liver parenchyma.