11-30 Liver Pathology 2 Flashcards
What are some categories of causes for liver injury?
Infectious
Immune mediated
Drug and Toxins
Metabolic
Genetic
Autoimmune Cholangiopathy
What are some infectious causes of liver injury?
Viral hepatitis - A, B, C, D, E
Give some examples of immune-mediated, drug and toxin, metabolic, genetic, and autoimmune cholangiopathy causes of liver injury.
•Infectious
–Viral hepatitis (A, B, C, D, E, ???)
•Immune Mediated
–Autoimmune hepatitis
•Drug and Toxin
–Acetaminophen
–Ethanol
•Metabolic
–Non-alcoholic fatty liver disease
•Genetic
–Hemochromatosis
–Wilson’s disease
–Alpha-1 antitrypsin deficiency
•Autoimmune Cholangiopathy
–Primary biliary cirrhosis
–Primary sclerosing cholangitis
What are the various clinicopathological syndromes of viral hepatitis?
- Acute asymptomatic infection with recovery (serologic evidence only)
- Acute symptomatic hepatitis with recovery
- Chronic hepatitis, with or without progression to cirrhosis
- Acute liver failure with massive to submassive hepatic necrosis
What parts of the hepatitis viruses can be tested for to determine infection status?
Ab to viral proteins
Viral proteins
Viral nucleic acid
Which Ab titers to hepatitis viral proteins are tested? What is the timeframe for a postive result?
•Antibody to viral proteins (often coat proteins) take day-weeks to develop (delay)
–IgM - initial response to acute infection
–IgG - long term response
- ongoing chronic infection
- past infection
How are viral proteins tested for hepatitis infection?
•Viral proteins
–rarely measurable
–exception: Hepatitis B
How is viral nucleic acid tested for hepatitis infection? Is this an accurate testing method?
•Viral nucleic acid
–Polymerase chain reaction assays available
–most infections will be diagnosed by detection of organism nucleic acid in the future
What is the typical course of an acute viral hepatitis in terms of:
viral replication
aminotransferase elevations
bilirubin elevations
fatigue/malaise
nausea/anorexia
What does icteric mean?
jaundice
In an acute viral hepatitis infection, what causes most of the damage to host hepatocytes?
Host immune system - hepatitis viruses are not directly cytopathic
What does acute hepatitis lead to?
Infection with a hepatotropic virus causes an acute episode of liver inflammation, referred to as acute hepatitis, which can lead to either spontaneous clearance of the infectious agent or its persistence, which in turn leads to chronic infection for a subset of these viruses.
What is the incubation period for a hepatitis viral infection? What are the symptoms?
Incubation period (Days to weeks) is generally characterized by nonspecific symptoms,
including fatigue, nausea, loss of appetite, flulike symptoms, and/or right upper quadrant pain
What are the immune-mediated symptoms in viral hepatitis infection?
•Immune-mediated symptoms, including rash, hives, arthralgias, and fever, are observed in 10 to 20% of patients during the preicteric phase.
What do you make of this case:
30 year old woman with a 1 week history of:
increasing fatigue
nausea
loss of taste for meat, oily foods
1-2 days of darkening urine,
“yellow eyes”
PE: jaundice and moderately tender liver
Lab tests: CBC: normal
Bilirubin 5.0 mg/dl (nl <1.1)
AST 955 IU/ml (nl <45)
ALT 1125 IU/ml (nl<55)
Alk phos 250 IU/ml (nl <140)
Albumin 4.2 gm/dl (3.5<nl></nl>
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Typical case history for acute viral hepatitis
What is ALT? Where is it housed, and what is it indicative of?
•Serum alanine transaminase (ALT):
Liver cell cytosol
(ALT>AST = viral hepatitis)
What is AST? Where is it housed, and what does it indicate?
•Serum aspartate transaminase (AST):
Liver cell mitochondria
(AST>ALT = Alcoholic hepatitis)
Why does alcohol affect AST levels?
AST stored in liver cell mitochondria
EtOH toxic to mitochondria, synthesis of ALT decreased with EtOH
What is ALP? Where is it stored?
ALP = Alkaline Phosphatase
stored in bile duct epithelium
When is jaundice detected clinically?
once the serum bilirubin level rises above 3 mg per dL
What is jaundice the result of?
•from interference in the normal metabolism of bilirubin (including uptake, transport, conjugation and excretion)
What would you expect the urine and stool colors to be in a case of obstructive jaundice?
pale/clay colored stool or ‘fishes’
dark colored urine
What is the cause of pale fishes or dark urine in obstructive jaundice?
system backup and subsequent overload of urobilinogen
Describe the histological findings consistent with lobular disarray.
Lobular disarray
– Ballooned hepatocytes and acidophilic bodies
– Individual or confluent hepatocyte dropout
– Zonal, bridging, or panlobular necrosis
– Sinusoidal inflammatory cells
– Prominent Kupffer cells
What is lobular disarray a sign of?
Found in histology specimen of acute hepatitis
Would you expect to see inflammation or fibrosis in lobular disarray?
Mild portal inflammation
No fibrosis
What’s this? What is this specific for?
Hepatic triad on left shows minimal inflammation
lobular disarray present in lower right, with ballooned hepatocytes
Acute hepatitis looks remarkably similar in histo, differentiate via Ab titers or PCR
What type of virus is hepatitis A virus?
ssRNA
What is the time frame of a hepatitis A infection?
self-limited disease,
incubation period of 2 to 6 wks
Does hepatitis A cause chronic hepatitis?
•Does not cause chronic hepatitis or a carrier state in the immunocompetent patient
How is hepatitis A spread?
•Generally transmitted via the oral-fecal route, person to person/contaminated water and foods
When does blood-borne transmission of HAV occur?
rarely
What are some risk factors for hepatitis A infection?
What is the receptor for HAV?
•Receptor for HAV (Picornavirus) is an integral membrane glycoprotein receptor
What does the genome of HAV work as? (hint: it’s a +ssRNA)
•Genome serves as a messenger RNA that encodes both structural and nonstructural viral proteins