Hepatobiliary Flashcards
(48 cards)
what do levels of billirubin, ALT, AST, ALP, GGT, albumin and PT mean in a LFT
- Bilirubin
- Unconjugatedhyperbilirubinaemiacould suggest:
- Haemolysis (e.g. haemolytic anaemia)
- Impaired conjugation (e.g. Gilbert’s syndrome)
- Conjugatedhyperbilirubinaemiacould suggest:
- Hepatocellular injury
- Cholestasis
- Unconjugatedhyperbilirubinaemiacould suggest:
- ALT
- useful marker ofhepatocellular injury (includes hepatitis, AFLD, NAFLD)
- AST
- grouped together with ALT
- AST > ALT is associated with cirrhosis and acute alcoholic hepatitis
- ALT > AST is associated with chronic liver disease
- ALP
- useful indirect marker of cholestasis
- ALT vs ALP rise
- Agreater than 10-fold increase in ALTand aless than 3-fold increase in ALPsuggests apredominantlyhepatocellular injury
- Aless than 10-fold increase in ALTand amore than 3-fold increase in ALPsuggestscholestasis
- GGT
- If ALP is increased, need to review GGT
- Raised GGT can suggest bile flow obstruction
- A markedly raised ALP with a raised GGT is highly suggestive of cholestasis
- Albumin
- Albuminlevels candecreasedue to:
- Liver disease resulting in a decreased production of albumin (e.g. cirrhosis).
- Inflammation triggering an acute phase response which temporarily decreases the liver’s production of albumin
- Albuminlevels candecreasedue to:
- Prothrombin time (PT)
- liver is responsible for synthesis of clotting factors, therefore hepatic pathology can impair this process
- increased PT can indicate liver disease
consequences of liver failure
- Coagulopathy: liver is main producer of a number of coagulation factors
- Hepatic Encephalopathy
- impaired hepatic metabolism → elevated serum levels of ammonia → impaired neuronal function
- Neurological signs: rigidity, hyperreflexia, asterixis
Cholestasis: impaired bile excretion
Portal hypertension (more for chronic LF)
leading causes of acute liver failure
Caused by drugs / toxins, Acute Hepatitis Virus (A,B and E), autoimmune hepatitis
histology of acute liver failure
Massive hepatic necrosis without obvious cell death
leading causes of chronic liver disease
Chronic Hepatitis B and C, Non-alcoholic fatty liver disease (NAFLD), Alcoholic liver disease
histological correlation of chronic liver failure
- Histological correlation: cirrhosis (usually)
DIFFERENCE BETWEEN CHRONIC LIVER DISEASE AND CIRRHOSIS
- Chronic liver failure is a clinical diagnosis that implies the liver has long term damage
- Cirrhosis is a pathologic diagnosis that requires investigations and radiology to show that the liver is nodular
- Hence, “cirrhosis” implies the presence of severe chronic liver disease, but is not a specific diagnosis and lacks clear prognostic implications
clinical features of chronic liver disease
- Cholestasis:
- jaundice → pruritus
- sclera icterus
- Hyperestrogenemia:
- palmar erythema
- spider angioma
- hypogonadism
- gynaecomastia (could associate with testicular atrophy)
- Coagulopathy
- Portal hypertension:
- Ascites
- Caput medusae
- Hepatic encephalopathy → asterixis (hepatic flap)
causes of acute on chronic liver failure
- Patients with chronic hepatitis B who become superinfected with hepatitis D
- Ascending cholangitis in patients with primary sclerosing cholangitis
morphology of liver cirrhosis
Parenchymal nodules
causes of liver cirrhosis
- Alcoholic liver disease
- Chronic hepatitis B virus infection
- Chronic hepatitis C virus infection
- Non-alcoholic fatty liver disease (NAFLD)
complications of liver cirrhosis
- Hepatic encephalopathy
- oesophageal varices
- increased risk of Hepatocellular carcinoma (HCC)
symptoms of acute hepatitis
- Jaundice
- Dark-coloured urine
- Poor appetite
which types of hepatitis are acute and which are chronic
- Acute
- usually only caused by Hep A, B, D, E
- Chronic hepatitis
- especially Hep C, with a small number of Hep B
hep A mode of transmission
faecal oral or water borne
hep A clinical features, incubation period, complications
Clinical features:
- benign self-limited disease: usually mild or asymptomatic, does not cause chronic hepatitis or carrier state
Incubation period
- incubation period: 2 - 6 weeks
Complications: uncommon to cause acute liver failure
hep A diagnosis and prevention
Diagnosis:
IgG anti-HAV (persists for years, giving lifelong immunity)
Prevention:
- Education on hygienic practices
- Traveller’s vaccine
hep B clinical features, incubation period, complications
Clinical features:
- Characteristic GROUND GLASS APPEARANCE
- Symptoms are initially non-specific (fever, jaundice, nausea)
Incubation period: 2 - 26 weeks
Complications:
- can cause acute hepatitis, acute hepatic failure, chronic hepatitis
- can lead to cirrhosis or carrier state
- only 5-10% of acute hepatitis patients progress to
chronic hepatitis
- Risk factor for HCC (hepatocellular carcinoma) even in the absence of cirrhosis
hep B mode of transmission
- mode of transmission: blood-borne
- high prevalence areas: vertical transmission
- low prevalence areas: sexual, infected blood & blood products (transfusions, needle stick contaminations, barbers, acupuncture, IVDA)
hep B diagnosis and prevention
diagnosis:
IgM anti-HBc & HbsAg in blood
HBeAg & HBV DNA are markers for infectivity
Carriers: usually HBsAg + but HBeAg - , low or undetectable HBV DNA
Prevention:
HBV vaccine
hep C mode of transmission, clinical features, incubation period, complications
- mode of transmission: blood borne
- drug abusers, blood products
- sexual, vertical transmission
- vertical and sexual transmission rare due to low circulating virus
- Symptoms
- usually asymptomatic, subclinical is common
- symptoms are milder than Hep B
Incubation period: 4-26 weeks incubation period
Complications similar to Hep B: chronic hepatitis, cirrhosis, chronic liver failure
hep C diagnosis and prevention
Diagnosis: HCV-RNA by PCR, anti-HCV
Prevention: no effective vaccine
hep D mode of transmission
- mode of transmission: blood borne
- IVDA, blood transfusions
- individuals can only be affected by HDV if they have been infected by HBV before
- highest prevalence in Middle East, Mediterranean, central Africa
hep D diagnosis and prevention
Diagnosis: IgM anti-HDV antibody is most reliable indicator of recent HDV exposure
Prevention:
Vaccination for HBV prevents HDV infection
hep E mode of transmission, clinical features, incubation period, complications
- Faecal-oral transmission (water-borne, zoonotic)
- zoonotic disease with animal reservoirs (monkey, cats, pigs)
Clinical features:
- Causes acute hepatitis
- usually self-limiting
- high mortality rate in pregnant women (~20%)
Incubation period
- 4-5 weeks incubation period
Complications:
Characteristically high rates of fatality amongst HEV-infected pregnant women