Liver n biliary Flashcards
what is the blood supply of the liver?
portal vein
hepatic artery
what are the cells of the liver?
Hepatocytes Bile ducts Blood vessels Endothelial cells Kupffer cells Stellate cells
what is the function of kupffer cells?
are the resident macrophagees of liver
what is the function of stellate cells?
- stores vit A. acts like fibroblasts - lays down collagen - so very. important in cirrhosis pathophysiology
which are the most metabolically active cells of the liver?
relevance?
the hepatocytes in zone 3*
this is where paracetamol and alcohol is metabolised
*remember there are 3 zones in the liver
what is the relevance of the zones in the liver?
the portal tract is in zone 1, oxygen coming into the liver is richest supply in zone 1 and reduces along the course to zone 3.
zones important in metabolism of diff things
what is special about liver endothelial cells?
they do not sit on a basement membrane
they are discontinuous - not attached / packed together
are fenestrated - many holes in them - allows bloods to pass from sinusoids into space of disse where it then contacts hepatocytes
what special cells are found in hepatic sinusoids?
kupffer cells - sit on endothelial cells
what happens to liver cells in liver injury?
Kupffer activated
Endothelial cells:
- lose fenestrations
- become tightly packed together
- > affects hepatocyte blood supply and nutrition
Activated stellate cells beging to lay down collagen
Hepatocytes lose microvilli
what are the features of cirrhosis?
- whole liver involved
- fibrosis
- nodules of regenerating hepatocytes
- distortion of liver vascular architecture:
intra- and extra- hepatic (e.g. gastro-oesophageal) shunting of blood - so you get unfiltered toxic blood going to heart and then to rest of bodyl
intra hepatic shunt - from portal tract straight into central vein
extra hepatic - doesnt go through liver at all
how can we classify cirrhosis?
according to aetiology:
1) alcohol / insulin resistance 2) viral hepatitis etc
what are the complications / consequences of cirrhosis?
- Portal hypertension
- Hepatic encephalopathy
- Liver cell cancer ; eg HCC
what are the causes of acute and chronic hepatitis ?
Acute:
- viruses; Hep A-E (all of them )
- drugs; paracetamol
Chronic:
- viral hepatitis; B,C,D (only some)
- drugs ; isoniazid
- auto-immune
in which case may cirrhosis bee reversible?
if of viral origin - aggressive treatment of th viral infection
which histological pattern is associated with acute hepatitis?
cause?
spotty necrosis
cause - hepatocyte damage + lymphocyte infiltration, all across the liver
it is not neutrophil infiltration as would expect because, the condition is clinically acute but it takes weeks to develop
define grade and stage in hepatitis?
severity of inflammation = grade
severity of fibrosis = stage (more important - determines risk of cirrhosis)
what is the pattern of fibrosis in chronic hepatitis?
starts within the portal tract and spreads outwards
Interface hepatitis (“piecemeal necrosis”), may be found in ___?
chronic hepatitis
what are the forms of alcoholic liver disease?
prognosis?
1) fatty liver
2) alcoholic hepatitis
3) cirrhosis
prognosis - all carry risk of developing cirrhosis.
fatty liver is reversible when stop drinking alcohol
balloon hepatocytes are pathognomic for?
Alcoholic Hepatitis
what are the histological features of Alcoholic Hepatitis?
Ballooning of hepatocytes ( +/- Mallory Denk Bodies)
Apoptosis
Pericellular fibrosis
Mainly seen in Zone 3
what is the key inflammatory cell in; Alcoholic Hepatitis
Neutrophil polymorph
what are the features of Non-alcoholic fatty liver disease (NAFLD) including non-alcoholic steatohepatitis (NASH)?
Histologically looks like alcoholic liver disease
Due to insulin resistance associated with raised BMI and diabetes
what is the epidemiology, aetiology and diagnostics for PRIMARY BILIARY CHOLANGITIS?
Previously primary biliary cirrhosis.
F> M
Bile duct loss associated with chronic inflammation (with granulomas) -> ‘granulomatous destruction of bile ducts’
Diagnostic test is detection of anti-mitochondrial antibodies - AMA
+ liver biopsy where you can see granuloma
what is the epidemiology, aetiology and diagnostics for PRIMARY SCLEROSING CHOLANGITIS ?
M > F
Periductal bile duct fibrosis leading to loss
Associated with ulcerative colitis
Increased risk of cholangiocarcinoma
Diagnostic test is bile duct imaging - beading appearance!
what is the aetiology of HAEMOCHROMATOSIS?
Genetically determined increased gut iron absorption
Gene on chromosome 6 (HFe)
Parenchymal damage to organs secondary to iron deposition (bronzed diabetes - due to pigmentation of the skin + damage to exocrine pancreas = diabetes)
what is HAEMOSIDEROSIS?
prognosis?
Exceess of iron deposition;
accumulation of iron in macrophages - in the liver kupffer cells - liver macrophages
-excess blood transfusions; eg SS, B thal
does not lead to cirrhosis
what is the epidemiology, aetiology and diagnostics for Wilsons disease?
Accumulation of copper due to failure of excretion by hepatocytes into the bile
Assessed by biopsy or biochemistry
Genes on chromosome 13
Accumulates in the liver and CNS (hepato-lenticular degeneration) including Kayser-Fleishcer rings
how can we stain for copper in liver?
Rhodanine stain;
golden-brown color against the blue counterstain.
what is the aetiology of autoimmune hepatitis? rx?
Active chronic hepatitis with plasma cells that are making ASMA;
Anti-smooth muscle actin antibodies in the serum
rx: Responds to steroids
what might you see on histology of autoimmune hepatitis?
plasma cells
clock faced nuclei
ALPHA-ONE ANTITRYPSIN DEFICIENCY can lead to which conditions?
Hepatitis and cirrhosis
list the causes of Hepatic Granulomas ?
Specific causes:
PBC
drugs
General causes:
TB
Sarcoid etc
the following are which kind of tumours:
1) liver cell adenoma
2) bile duct adenoma
3) haemangioma
benign liver tumours
adenomas dont have capsules - well dermacated but no capsules
the following are which kind of tumours:
- hepatocellular carcinoma
- hepatoblastoma
- cholangiocarcinoma
- haemangiosarcoma
malignant liver tumours - PRIMARY
why is the liver a common site of metastatic cancer?
Portal Venous System - drains many sites
how canyou tell something is adenocarcinoma on histology?
gland forming with mucin
what are the associations of Cholangiocarcinoma?
Associated with:
PSC
Worm infections
Cirrhosis
Can arise from: intrahepatic ducts extrahepatic ducts (including gall bladder)
