Viral Hepatitis & Interpretation of Liver function tests Flashcards
What causes hepatitis [13]
Hep ABCDE
CMV
EBV
HIV
Herpes
Enterovirus
VZV
Rubella
Q-fever
Yellow fever
Psittacosis
Leptospirosis
Ischaemia
How is hep A spread [2]
Foecal oral eg ano-oral sex
Contaminated food or drink
Hep A Incubation period Prognosis Presentation in <5yo Presentation in adult & adolescent [4]
Short incubation - 28 days
Prog: Benign and self limiting
<5yo: subclinical, no jaundice Adult, adolescent: - fever, malaise, anorexia - N&V, abdominal pain - intrahepatic jaundice - hepatosplenomegaly 10-14d later (dark urine, pale stool)
Who is at high risk and offered immunisation [6]
Travellers CLD Occupational exposure Haemophiliac Homosexual PWID
How do you Dx Hep A [3]
LFT increased
o Anti-HAV IgM: present at onset of symptoms; falls to non-detectable levels by 3-6m
o Anti-HAV IgG: indicates previous infection
How do you treat Hep A [5]
No treatment as self limiting
Relieve pain / itching / nausea
Prevention
- General: good personal hygiene, sanitation
- Patients should avoid work or school for 7 days after symptom onset.
What are complications of Hep A
Compare the protection that active versus passive immunization confers
Prolonged fatigue / jaundice
No chronic damage or HCC risk
- Passive immunisation: HNIG provides immediate passive protection for 4m for close contacts
- Active immunisation: inactivated vaccine gives single dose protection by 2w followed by a booster at 6-12m for 20y protection
How is Hep B spread [5]
Describe epidemiology of Hep B [2]
Blood Sexual Vertical (mother to baby) Horizontal (households) Carrier states exist
Ep: sub-Saharan Africa and SEA
How infective is Hep B?
Incubation
What are 2 rare complications of Hep B?
Very 100x more than HIV
Long incubation - 6 weeks (need to wait 4 to test)
Complications
- intrahepatic jaundice
- fulminating hepatitis
What are the symptoms of Hep B?
Acute [4]
Chronic [5]
Acute
- Onset: within few weeks or 6m
- Anorexia, lethargy, fever
- N+V+D, abdominal discomfort
- Pruritus, dark urine, pale stool
Chronic:
- Hepatitis
- Fulminant liver failure
- HCC
- GN
- Cryoglobulinemia
Who is at risk of hep B [7]
MSM, Travellers, Haemophiilac, dialysis IVDU, Tattoo / piercing Blood transfusion pre-screen Healthcare workers Chronic liver Babies born to infected mothers
What is fulminant hepatic encephalopathy [4]
DIC
Encephalopathy
Hypoglycaemia
Prolonged PT
Hep B serology [6]
HBsAg = surface antigen (first to appear in acute infection)
HBcAg = core antigen
- IgM
- IgG
HBeAg = breakdown of core antigen in infection liver cells
HBV DNA = viral DNA
What suggests highly infectious
HBeAg + HBV DNA
Consider infectious even if e antigen is -ve due to risk of mutation
What suggests chronic hep B
HBeAg >6 months
Anti-HBc IgG
How do you interpret serology
Anti-HBs
- Implies immunity, develop as lose surface antigen and infection clears
- Either exposure or immunisation
- -ve in chronic as not cleared
Anti-HBc
- C = caught (previous or current)
- -ve if vaccine
IgM HBc
- Acute and lasts 6 months
IgG HBc
- Persists forever and shows past infection NOT vaccine
Anti-IBe
- Inactive virus
What suggests previous immunisation [2]
Anti-Hbs
All other -ve
What suggests hep B 6 months ago [4]
Anti-Hbs
Anti-HBc
IgG HBc
HBsAg -ve
What suggest previous hep B but now carrier [2]
HbsAg +ve = chronic
Anti-HBc
How do you dx hep B [2]
Serology
Liver enzymes
What should you do if testing for hep B and why?
Test for HIV and hep D
Hep D because it requires HBV surface particle to complete replication and transmission cycle
Who gets tested for hep B [5]
All demographics with risk factors + Anti-TB tx Immunosuppressed Persistent abnormal LFT with no cause Pregnant
How do you Rx acute hep B
No Rx
Self limiting
What do you advice someone with hep B [5]
Public health <5% become chronic NO alcohol / sex Household precaution Vaccinate contacts
When do you test for HIV / HBV / HCV
6 months
What are complications of HBV [7]
10% chronic Cirrhosis, Liver failure HCC Membranous GN Polyarteritis nodosa Cyroglobulinuria Vasculitis rash
When do you consider treatment of chronic [5]
2+ of:
- Abnormal LFT
- High viral load
- Abnormal fibroscan / cirrhosis
- HbeAg +ve (DNA / ALT raised)
What do you do otherwise
Monitor
Some stages of chronic are highly infectious
How would you treat Hep B [3]
- Anti-viral (nucleoside analogue) = 1st line
Pegylated interferon (anti-viral + immune) - Liver transplant if cirrhotic
- Monitor renal function
Interferon less successful in chronic
What is prophylaxis in hep B [2]
Vaccine to newborn and human Ig
If on chemo / immunosuppressed / contact = vaccine and Ig
What do you do after vaccine
Check Anti-Hbs levels
How do you monitor and follow up hep B [3]
In clinic:
- ALT / LFT
- Fibroscan
- Advise if become immunocompromised
Who is at risk of no response to vaccine [5]
Obesity Alcohol Smoking >40 Immunocompromsie
How do you treat hep B in pregnancy [5]
- Tenofavir
- Obstetric team to advise delivery
- Passive and active immunisation - newborn
- Can breast feed
- Test baby at 1 year
How is hep C. spread [3]
Blood/tissue donation
IVDU
Vertical and breastfeeding transmission is rare
Can you become immune to hep C
Incubation period
No so can get reinfected
Short incubation 6-9w
What are the symptoms of hep C [6]
Flu like symptoms - Malaise - Anorexia - Fatigue - Arthralgia 10% jaundice
What are complications of hep C [6]
85% = chronic hepatitis Cirrhosis HCC Sjogren Cryoglobulinuria Membranous GN
Who is more likely to het fulminant hepatitis [2]
Pregnancy
Immunocompromised
What suggests cirrhosis [2]
ALT up
Platelet down
Who is at risk of hep C [4]
Alcohol accelerates
IVDU
Haemophiliac, Dialysis
Tattoo / piercing
How do you Dx hep C [4]
Increased LFTs
HCV RNA - PCR * detectable 1-2m
Anti-HCV IgG - detectable 3m
No IgM test
When do you retest for hep C
If Ab +ve but RNA -ve? What is the likely diagnosis?
3-6 months to make sure
If Ab +ve but RNA -ve = cleared or treated
When do you treat hep C
If Ab and antigen +ve
How do you treat hep C [5]
General:
- Avoid alcohol
- Test for other BBV
- Offer immunisation
Antivirals
- protease inhibitor combination e.g. DACLATASVIR + SOFOSBUVIR +/- RIBAVARIN
- 3 months
What are SE of ribavirin [3]
Teratogenic
Haemolytic anaemia
Cough
What are the SE of interferon [5]
Thrombocytopenia Leukapenia Fatigue Depression Flu
What does response to Rx of hep C depend on [4]
Age
Gender
Liver disease
Amount of virus
What are types of response to hep C Rx
Non Responder
Viral Breakthrough
Relapse - when Rx stopped
Sustained viral after 6 months = 95%
How is hep D transmitted
Same routes as hep B
But requires HBV surface particle to complete replication and transmission cycle
What are the symptoms of hep D
More severe hep B and rapid progression if co-infection
How do you Dx hep D [2]
IgM and IgG
Reverse PCR = Dx
How do you treat hep D [4]
NO vaccine
Pegylated interferon
Transplant
Prevent hep B
What are the complications of hep D [4]
Chronic B
Cirrhosis
HCC
Fulminant hepatitis
How is hep E spread
Foecal oral
What is the most common hepatitis
Incubation period
Hep E
Screen in any acute liver injury
Short incubation = 40 days
Clinical presentation Hep E [3]
- Presentation resembles HAV
- Subclinical/mild in women, more severe in elderly men
- Extra-hepatic features
Jaundice <1%
When is hep E dangerous [2]
Pregnancy = high infant mortality (diff hep A) due to tendency to progress to fulminant
Elderly men
What are extra hepatic complications of hep E [6]
AKI - think if no cause Pancreatitis Bell's Palsy, GBS Neuralgic arthropathy - brachial plexus pain Arthritis Anaemia
Who is at risk of hep E
Occupational - farm
Blood transfusion due to short viraemia phase
When do you suspect hep E
Deranged LFT for alcohol consumption
How do you Dx hep E [3]
IgG and IgM
HEV PCR serology
Abnormal LFT
What is chronic hep E [2]
> 3 months
No dip in HEV RNA 6 months
How do you treat hep E [2]
No specific Rx or vaccine
Clean water and avoid undercooked meat
What are complications of hep E [2]
Persistent in immunocompromsied
Liver failure if CLD
Interpretation of liver function tests: source
Bilirubin
ALT and AST
ALP and GGT
Albumin
PT or INR
Bilirubin: Hb breakdown
ALT and AST: hepatocytes
ALP and GGT: biliary epithelium
Albumin: synthesised by hepatocytes
PT or INR: synthesised by livers
Different patterns of liver biochemistry suggesting different causes:
Hepatocellular
Cholestatic
Isolated hyperbilirubinemia
- Hepatocellular: ALT and aspartate transaminase (AST) raised in excess of other liver enzymes.
- Cholestatic: ALP and gamma-glutamyl transferase (GGT) raised in excess of other liver enzymes.
- Isolated hyperbilirubinaemia (other liver biochemistry normal): conjugated (e.g. Gilbert’s) or
unconjugated (e.g. haemolysis).
Mechanisms of jaundice
- Overproduction of bilirubin: predominantly unconjugated, rarely >70 μmol/L, caused by increased red cell breakdown (i.e. haemolysis, haematoma dissolution).
- Failure of bilirubin conjugation: either impaired delivery of bilirubin to the liver (e.g. congestive cardiac failure, portosystemic shunting) or enzymatic defects (e.g. Gilberts disease, Crigler–Najjar syndrome).
- Failure to export bilirubin across the canalicular membrane: conjugated. Divided into intrahepatic (e.g. viral or alcoholic hepatitis, MRP2 mutation in Dubin–Johnson syndrome) and extrahepatic (e.g. bil- iary obstruction). May also occur in non-hepatic conditions (e.g. sepsis).
Liver screen [7]
FBC
Ferritin
Copper studies
BBV screen
Ig
Anti-mitochondrial, anti-smooth muscle or anti-nuclear antibodies
Alpha-1 antitrypsin
Liver screen - expected abnormalities and what they suggest?
FBC, ferritin, Immunoglobulins
FBC- macrocytosis, thrombocytopenia, may indicate alcohol excess, hypersplenism relation to portal hypertension
Ferritin - elevated ferritin, associated with haematochromatosis, non-alcoholic and alcoholic fatty liver disease
Immunoglobulins - elevated IgG and IgM suggesting PBC, autoimmune liver disease.
Patterns of abnormal LFT (raised more than 5x the upper limit of normal)
ALT>AST
AST>ALT
ALT>AST
- Autoimmune hepatitis
- Coeliac disease
- Drug induced liver injury
- Haemachromatosis
- NAFLD
- Viral hepatitis
- Wilsons disease
AST>ALT
- Alcoholic liver disease
- Cirrhosis