hepatology Flashcards
What are the majority of liver cancers?
metastasis
small proportion are hepatocellular carcinomas (HCC)
describe the pathophysiology/aetiology of an hepatocellular carcinoma?
arises as a result of chronic inflammation of the liver (hepatitis and cirrhosis) hepatitis B and C chronic alcohol hereditary haemochromatosis primary biliary cirrhosis aflatoxin smoking, FHx, age
what are the symptoms associated with HCC?
vague symptoms initially: fatigue, fever, weight loss and lethargy. Rare symptom is a dull ache in RUQ
later symptoms: ascites, signs associated with portal hypertension and jaundice
in terms of time scale how to jaundice compare in HCC and cholangiocarcinoma?
jaundice is an early sign in cholangiocarcinoma but a late sign in HCC
what does the liver feel like on examination in someone with HCC?
irregular
craggy
tender
enlarged
what does the AST: ALT ratio tell us?
if >2 it is likely to be alcoholic liver disease
if around 1 likely to be viral hepatitis
what investigations would you do if you suspect HCC?
LFTs, FBC
a-fetoprotein - raised in 70% of cases (can be used to monitor response to treatment
USS - if mass >2 cm and raised AFP then very likely to be cancer
CT and MRI
fine needle aspiration biopsy if still in doubt
why do we try to avoid a biopsy of the liver by fine needle aspiration if we suspect HCC?
may help to spread the tumour
what staging systems are used for liver cancer?
Barcelona clinic liver cancer staging system (BCLC) - looks at stage, liver function, physical state and cancer related symptoms to guide treatment
Child-Pugh score- predictor of mortality from cirrhosis
what is the surgical management of HCC?
resection transplantation if: - one lesion <5cm or 3 lesions <3cm - no extrahepatic manifestations - no vascular infiltration
what is the non-surgical management of HCC?
image guided ablation - use USS to guide probe and then use different things to kill tumour e.g. microwave probe or alcohol injections. this induces necrosis of malignant tissue. however only good for small tumours - early stage
transartifical chemoembolization - BCLC stage B tumours - high con chemo drugs injected into the hepatic artery and then embolising agent (Cellulose) is added to induce ischaemia
how can we prevent HCC?
Hep B vaccine
education - don’t drink too much alcohol
surveillance of those at risk e.g. hemochromatosis
where are the most common places liver metastasis come from?
bowel (via portal circulation), lung, breast, pancreas and stomach
what does raised ALP show?
can be raised by liver (biliary obstruction or hepatic metastasis) , bone (pagets, fractures, renal bone disease, osteomalacia) and placental pathologies.
if the raised ALP mirrors raised gGT it is more likely to be hepatic in origin
what does raised gGT show?
used to assess if the raised ALP is due to liver or another pathology. associated with cholangiocyte damage and liver disease
more specific to liver damage than ALP
can also be elevated in obesity, hyperlipidaemia, diabetes, congestive cardiac failure, kidney/prostate and pancreas.
if both ALP and aGT are raised what does this suggest?
there is damage to the liver - these two are correlated and both linked to liver damage (although each linked to other causes, if they correlate it makes liver damage but more likely)
why do enzyme get raised in liver damage?
damage leads to enzymes leaking from liver cells.
when is AST (aspartate aminotransferase ) raised?
liver, cardiac, skeletal muscle pathologies
also kidneys and pancreas
when in ALT (alanine aminotransferase) raised?
specific to liver pathology. short half life and thus will follow pattern of liver damage and healing quite accurately.
what is meant by a mild, moderate and marked increase in the aminotransferases?
mild (<300): cirrhosis, non alcoholic fatty liver, HCC, haemachromatosis/Wilsons
moderate (300-500) chronic/alcohol/autoimmune hepatitis, biliary obstruction
marked (1000s): toxic drug induced (paracetamol), acute viral hepatitis, liver ischaemia
what is gGT more specifically associated with in terms of liver damage?
alcohol abuse
enzyme inducing drugs
what are other tests that indicate liver damage?
low albumin
high INR
total protein (albumin and globulins) can be raised in active hepatitis and in chronic inflammation
low albumin + high protein = myeloma
low albumin + normal protein = infection
low both = advanced cirrhosis , malnutrition
what are the normal liver functions?
nutrition - glycogen store, gluconeogenesis, glucogenolysis and makes cholesterol
Absorption of fats and fat soluble vitamins (bile)
Makes clotting factors
immune function - kupfer cells, acute phase response
detoxification - CYP450 enzymes
makes albumin and binding proteins
what is fulminant hepatic failure?
clinical syndrome resulting from massive necrosis of liver cells leading to impairment of liver function
what is hyperacute liver failure?
very rapid onset - encephalopathy within 7 days of jaundice onset
what are the causes of acute liver failure?
infection: viral (Hep A, B,C, CMV), yellow fever, malaria
drugs: isoniazid, paracetamol, ethanol, mushroom toxins
vascular: DIC, veno-occlusion
genetic: autoimmune hepatitis, haemachromatosis, primary biliary cirrhosis, wilsons (however mainly chronic), alpha1 antitrypsin deficiency
malignancy
pre-eclampsia
what are the signs of acute liver failure?
jaundice
fetor hepaticus (breath that smells like pear drops)
flapping tremor
constructional apraxia (cant copy 5 point object)
hepatic encephalopathy
oedema/ascites
may have signs of chronic - suggesting acute on chronic
how do we classify acute liver failure?
type 1: rapidly progressive deterioration (survival 2 weeks)
type 2: steady deterioration (survival 6 months)
what is pathogenesis of hepatic encephalopathy?
nitrogenous waste builds up (liver function impaired so urea cycle is not working properly)
astrocytes aim to remove nitrogenous waste by converting glutamate to glutamine
glutamine effects osmotic pressure -cerebral oedema results
what are the different grades of hepatic encephalopathy?
grade 1: altered mood/behaviour, dyspraxia, sleep disturbance, no flap
grade 2: increased drowsiness, confusion and slurred speech, liver flap
grade 3: flap, restless, almost unconscious (stupor)
grade 4: coma
what investigations would you do to find the cause of acute liver failure?
LFTs - look at ratio of AST:ALT, gGT, bilirubin etc
glucose and paracetamol levels
virology screen - Ab for Hep B/C/CMV /EBV
a1 antitrypsin deficiency screen
screen for autoAb
ferritin levels - haemochromatosis
serum copper and caeruloplasmin and 24 hour urinary copper - wilsons.
USS, CXR, dopler of portal vein
list some hepatotoxic drugs
paracetamol, methotrexate, isoniazid, azathioprine, oestrogen, salicyclates, tetracycline
what drugs should be avoided in acute liver failure?
drugs that constipate (opiates, diuretics - risk of encephalopathy)
hepatotoxic drugs
oral hypoglycaemics
warfarins effects will be enhanced
how is acute liver failure managed?
manage in ITU
correct underlying cause
- monitor temperature, resp rate, pulse , BP, pupils, urine output, FBC, U&Es and LFTs daily - monitor glucose 1-4 hourly
glucose given IV to avoid hypoglycaemia
give thiamine and folate supplements
treat any seizures with lorazepam
treat complications
what is given for paracetamol overdose?
N-acetyl cysteine
why may PPIs be given in acute liver failure?
reduce risk of stress ulceration
how are the complications of acute liver failure managed?
cerebral oedema: mannitol
ascites: fluid restriction, low salt, diuretic
bleeding: vit K, FFP, blood or platelets
encephalopathy: lactulose to clear gut bacteria so there are fewer nitrogen forming gut bacteria
IV albumin
splanchnic vasoconstrictors
sepsis - Tazocin - avoid gentamicin (renal failure)
what is cirrhosis?
a condition where the liver has become progressively replaced by scar tissue due to chronic inflammation. the damage is irreversible. there is loss of hepatic architecture with fibrosis and nodular regeneration
what are the causes of chronic liver failure/cirrhosis?
chronic alcohol abuse
chronic hep B/C ingection
haemachromatosis, a1-antitrypsin deficiency, wilsons
non-alcoholic fatty liver disease
autoimmune: primary biliary cirrhosis, primary sclerosing cholangitis, autoimmune hepatitis
drugs: amiodarone, methotrexate, methyl dopa
what are the signs of chronic liver failure?
high oestrogen: gynecomastia, spider naevi , palmar erythema
hypoalbumin: leukonychia, ascites
terrys nails: distal 1/3 of nail reddened by telangiectasia
clubbing , dupuytrons contractures
hepatomegaly or small liver
low clotting: straie
what are the complications of hepatic failure?
hypoglycaemia coagulopathy - increased INR encephalopathy - liver flap hypoalbumin - oedema , can lead to renal failure low immune factors - sepsis /infection
what are the complications of cirrhosis?
hepatic failure
portal hypertension
HCC risk
how would you investigate the cause and complications of cirrhosis?
LFTs
albumin + INR levels
WCC and platelets - if low suggest hyposplenism
USS and duplex - fatty liver, hepatic vein thrombosis
causes:
- iron and ferritin levels - haemachromatosis
- caeruloplasmin - wilsons
- A fetoprotein
- A1 antitrypsin deficiency
- serology for virus
- autoAb
biopsy for definite diagnosis
how can we manage chronic liver failure?
general : improve nutrition, stop alcohol, avoid NSAIDs, sedative and opiates.
colestyramine helps pruritis
treat specific causes or complications
USS and alpha fetoprotein every 3-6 months to screen for HCC
liver transplant - definite cure
why is peritonitis a complication of cirrhosis? how can we treat bacterial peritonitis ?
ascites develops due to low albumin and portal hypertension
fluid stasis favours bacterial growth
can confirm diagnosis by ascetic tap - fluid sent to MC&S
treat with cefotaxime/tazocin and metronidazole
how does the child-pugh grade work?
points are given for level of bilirubin, albumin, prothrombin time, ascites and encephalopathy. the higher the points the higher the grade. if score is >8 the risk of variceal bleeding is much higher
what is hereditary haemochromatosis?
autosomal recessive disease
abnormal iron metabolism - increased iron absorption from the gut and then deposition of iron in joints, liver, heart, pancreas, pituitary , adrenals and skin
caused by HFE gene
how does hemochromatosis present?
early: lethargy, MCP joint arthralgia, erectile dysfunction
later: grey pigmented skin , signs of chronic liver disease, dilated cardiomyopathy, signs of bronze diabetes, signs of pituitary dysfunction
how can secondary hemochromatosis occur?
if transfusions are given e.g. in thalassemia
what investigations would you do for haemochromatosis?
raised LFTs, raised serum ferritin, HFE genotype
Xray of hands - chondrocalcinosis of MCPJ
Liver MRI - Fe overload
liver biopsy - confirms perl’s stain
ECHO/ECG - cardiomyopathy
what are the irreversible complications of haemachromatosis?
cirrhosis, diabetes, hypogonadotrophic hypogonadism, arthropathy
what are the reversible complications of haemachromatosis?
cardiomyopathy
skin pigmentation
how do we manage haemochromatosis?
Venesect: reduces ferritin levels - returns life expentancy to normal but any cirrhosis that has already occurred is irreversible
monitor LFTs, glucose , screen for HCC
advice a low iron diet
screen first degree relatives
what is the pathogenesis behind a1 antitrypsin deficiency?
autosomal recessive
a1antitrypsin is a glycoprotein of the family of serine protease inhibitors that is usually made in the liver
normally functions in controlling inflammatory cascades.
therefore deficiency leads to uncontrolled inflammatory cascades
e.g. normally protects lungs against elastase made my neutrophils therefore excess elastase results in emphysema
in the liver there is a build up of abnormal protein resulting in cirrhosis and HCC
can also cause pancreatitis, gall stones and is associated with Wegners
what are the symptoms of a1 antitrypsin deficiency ?
dyspnoea - due to emphysema
jaundice - due to cirrhosis and cholestasis
how would you test for a1 antitrypsin deficiency?
serum a1 antitrypsin levels - usually low
liver biopsy - will show diastase resistant globules
genetic testing
phenotyping - look at protiens by isoelectric focussing
CT of lung
why does smoking worsen a1 antitrypsin deficiency?
smoking increases elastase production by neutrophils
what management is required for a1 antitrypsin?
stop smoking can give IV a1 AT supportive treatment of liver and lungs may need lung/liver transplant regular screens for HCC
what the pathophysiology of primary biliary cirrhosis?
an autoimmune disease leading to damage of interlobular bile ducts by granulomatous inflammation.
leads to cholestasis, fibrosis and cirrhosis and portal hypertension
caused by unknown environmental triggers and genetic predisposion
which auto Ab are present in primary biliary cirrhosis?
anti mitochondrial
what age does primary biliary cirrhosis mainly present?
50 years
what symptoms are associated with primary biliary cirrhosis?
often asymptomatic (ALP raised on routine test) lethargy and sleepiness jaundice and pruritus skin pigmentation and xanthomas hepatosplenomegaly
what are the complications associated with primary biliary cirrhosis?
cirrhosis of liver and HCC
osteoporosis
malabsorption of fat - steatorrhoea
osteomalacia (less vit D due to fat absorption)
coagulopathy (less vit K due to low fat absorp)
what is found on investigating primary biliary cirrhosis?
LFTS: ALP and gGT raised, slightly raised AST and ALT
in late disease: raised bilirubin, low albumin, increased prothrombin time (INR)
USS can rule out extra-hepatic cholestasis
USS can also show liver to be normal, fatty or cirrhosis
fibroscan - degree of cirrhosis
biopsy - not usually needed but can show granulomatous inflammation around bile ducts
how do we treat primary biliary cirrhosis?
specific:
Ursodeoxycholic acid - high dose - emulsifies bile to prevent it blocking up ducts
liver transplant for end stage
Supportive: Colestyramine for pruritus codeine for diarrhoea osteoporosis prevention Fat soluble vitamin prophylaxis - ADEK
monitor regularly LFTs and ultrasound