GI - Hepatits: D, B, Ischaemic, Auto-immune Flashcards
What is Hepatitis D?
- Single stranded RNA virus - incomplete virus t/f requires hepatitis B surface antigen to complete its replication and transmission cycle
- transmitted parenterally: exchange of bodily fluids - pts may be infected with Hep B and hep D at same time
What is the difference between hep D co-infection and superinfection?
- Co-infection: hep B and D infection at same time
- Superinfection: hepatitis B surface antigen positive pt subsequently develops hep D infection - associated with high risk of fulminant hepatitis, chronic hepatitis status and cirrhosis
What symptoms does Hep D cause?
- loss of appetite
- Nausea/vomiting
- tiredness
- pain in RUQ
- muscle/joint pain
- jaundice
How do you diagnose and Rx hep D?
- Dx: reverse polymerase chain reaction of hep D RNA
- Current Rx: interferon currently used - poor evidence base
What is ischaemic hepatitis? How is it diagnosed?
- Diffuse hepatic injury hepatic injury - results from acute hypoperfusion ‘shock liver’
- Not acute inflammatory process - often in conjunction with AKI (tubular necrosis) or other end organ dysfunction
- Dx: presence of inciting event (eg cardiac arrest/AKI) and aminotransferase levels exceeding 1000 international units/L or 50x upper limit of normal
Interpret the following Hepatitis B serology:
- HBsAg
- Anti-HBs
- Anti-HBc
HBsAg: surface antigen - indicates infection
- If present for 1-6 months then acute disease
- If present for >6 months then implies chronic disease - ie pt is infective)
Anti-HBs: surface antibody
- present implies immunity: either via exposure or immunisation
- Negative in chronic disease b/c haven’t developed immune response to it - can’t clear it
Anti-HBc (core antigen)
- Present: previous or current infection
- IgM anti-Hsbc appears during acute/recent hep B infection and is present for 6 months
- IgG anti-HBc persists if >6 months
Interpret following Hep B serology:
- HbeAg
- HBeAb
HbeAg: tells you whether they are infective or not
-Made by breakdown of core antigen from infected liver cells - if present then virus is replicating
HbeAb (IgG): marker of immune response
-this is only positive in pts who have had Hep B at some point, developed response and cleared it - helps differentiate between people who have had infection (+ve) and who have had vaccine (-ve)
25 year old man is found to have positive HbsAg after donating blood - asymptomatic and examination normal
Bilirubin: 19, ALT 32, ALP 55
- HbsAg: positive
- Anti-Hbc IgM: negative
- HbeAg (e antigen): positive
- HbeAb (e antibody): negative
- HBV DNA PCR 1.6 x 10^6 copies/ml
What is his status and what should you do with him?
- HbsAg: infected
- Anti-Hbc IgM: not acute
- HbeAg (e antigen): virus replicating
- HbeAb (e antibody): immune system has not responded yet
- HBV DNA PCR: very high viral load
High viral load and infected - don’t treat but warn of infection risk
25 year old man is found to have positive HbsAg after donating blood - asymptomatic and examination normal
Bilirubin: 19, ALT 22, ALP 55
- HbsAg: positive
- Anti-Hbc IgM: negative
- HbeAg (e antigen): negative
- HbeAb (e antibody): positive
- HBV DNA PCR 650 copies/ml
What is his status and what should you do with him?
- HbsAg: has hep B
- Anti-Hbc IgM: not acute infection
- HbeAg (e antigen): made by replicating virtues
- HbeAb (e antibody): immune system has reacted but can’t eliminate completely
- HBV DNA PCR: low ish
Low risk carrier of Hep B - no Rx given
25 year old man is found to have positive HbsAg after donating blood - asymptomatic and examination normal
Bilirubin: 23, ALT 176, ALP 55
- HbsAg: positive
- Anti-Hbc IgM: negative
- HbeAg (e antigen): positive
- HbeAb (e antibody): negative
- HBV DNA PCR 1.6 x 10^6 copies/ml
What is his status and what should you do with him?
- HbsAg: has hep B
- Anti-Hbc IgM: not acute infection - chronic
- HbeAg (e antigen): virus is actively replicating
- HbeAb (e antibody): immune system is not responding
- HBV DNA PCR: very high viral load
This pt has chronic active Hep B with a very limited immune response - warrant Rx with Tenofovir
A 25 year old man presents with jaundice
Bilirubin: 123, ALT 1976, ALP 55
- HbsAg: positive
- Anti-Hbc IgM: positive
- HbeAg (e antigen): positive
- HbeAb (e antibody): positive
What is his status and what should you do with him?
- HbsAg: positive - has hep B
- Anti-Hbc IgM: positive - acute phase of disease
- HbeAg (e antigen): positive -virus is actively replicating
- HbeAb (e antibody): negative - immune system hasn’t responded yet
Pt is in acute Hep B - has 95% chance of making a full recovery
- Few pts with get fulminant hepatic failure
- Few pts develop chronic hep B (check serum ag in a few months)
What is auto-immune hepatitis? What types are there?
-Condition of unknown aetiology: commonly affects young females
Type I:
- ANA and/or anti-smooth muscle antibodies present
- Affects both adults and children
Type II
- Anti-liver/kidney microsomal type 1 antibodies (LKM1)
- Affects children only
Type III
- Soluble liver-kidney antigen
- Affects adults in middle-age
What are the features of auto-immune hepatitis?
- May present with signs of chronic liver disease
- Acute hepatitis: fever, jaundice, etc (only 25% present this way)
- amenorrhea: common
- ANA/SMA/LKM1 antibodies, raised IgG levels
What do liver biopsies show in auto-immune hepatitis?
-inflammation extending beyond limiting plate ‘piecemeal necrosis’ and bridging necrosis
What is the Mx for auto-immune hepatitis?
- Steroids
- Other immunosuppressants: Azathioprine
- Liver transplant
