Liver Disease Flashcards
Why does ALP increase in pregnancy?
Placental production of ALP, which increases with successive trimesters.
In women who have hyperemesis severe enough to cause fluid, electrolyte and nutritional disturbance, what % are associated with abnormal LFTs?
What abnormalities are seen?
50%
Moderate rise in transaminases (50-200)
Slightly raised bilirubin
How is Hep B transmitted?
Blood borne
Sexual, vertical or via blood
For chronic carriers of Hep B, what is the risk of getting cirrhosis or hepatocellular cancer?
And chance of dying from it?
HCC - 40%
Death - 25%
For mothers with Hep B who are both HBsAg and HBeAG positive, what is the risk of vertical transmission?
70-90%
RANZCOG
When does mother to child transmission of Hep B occur?
Labour and Delivery (95%)
Antenatally (5%) - TPTL - Abruption - Invasive procedures increase the risk
For a neonate infected with Hep B at birth, what is the chance of becoming a chronic carrier?
Why?
> 90%
Young age at contracting virus correlates with risk of chronic hep B (adults <5% become chronic HBV carriers).
Perinatal transmission is leading cause of transmission in endemic countries.
For mothers with Hep B who are HBsAg positive but HBeAG negative, what is the risk of vertical transmission?
10-40%
For HepB, when is antiviral therapy indicated in pregnancy?
Active disease or cirrhosis
Third trimester in women with high viral loads >200,000 or >6 log copies, or HBeAg positive to reduce the risk of perinatal transmission at birth.
Tenofovir should be started ideally 30-32 weeks and continued till 6 weeks post partum, under the supervision of designated hepatology team.
For HepB in pregnancy, what is the preferred antiviral if required?
What is the evidence for its use?
Tenofovir
Reduced neonatal infection at 28 weeks from 18% in controls to 5% in women taking tenofovir.
All neonates born to women with acute or chronic HBV should be given…
HepB Immunoglobulin and HBV vaccine after birth, ideally within 12 hours of birth
Usual HPV vaccine as per the vaccination program - at 6wks, 3 month and 5 month.
Serology for HBV immunity or infection should be checked at 5 months.
What is the commonest risk factor for Hep C?
IVDU (75%)
In Hep C, what is the risk of chronic infection and progressive cirrhosis?
80% risk of chronic infection
30% develop slowly progressive cirrhosis
What is the preferred therapy for Hep C?
Interferon-alpha combined with ribavirin
Women with Hep C have an increased risk of what complication in pregnancy?
Obstetric cholestasis / Intrahepatic cholestasis of pregnancy
May present earlier than usual
In Hep C in pregnancy, what is the risk of vertical transmission?
<5%
Increased if HIV confection or viremia (positive HCV RNA)
In which type of hepatitis is there a dramatically increased mortality in pregnant women?
Hep E.
With acute Hep E infection
Mortality rate = 5%
Also increased risk of hepatic encephalopathy and fulminant hepatic failure (15-20%)
Particularly if the virus is acquired in the third trimester
Transmission by faeco-oral route.
Usually self-limiting similar to hep A in the immune competent host.
Also HSV hepatitis
Which type causes HSV Hepatitis?
Most are primary HSV Type 2 infections
What is the incidence of Obstetric Cholestasis?
0.5-1% in UK
Indian and Pakistani women at higher risk
What is the pathogenesis of Obstetric Cholestasis?
Genetic inheritance - familial clustering and evidence for genes for transmembrane transporters being implicated.
Elevated oestrogens are associated with significant impairment in sulphation capacity (sulphation of bile acids is important in attenuating their Cholestatic potential).
Progestogens may also play a role.
Reproductive hormones also affect the function of bile acid transports within the hepatocytes
Environmental - low vit D and selenium
Pre-exisitng liver disease (hep C and B)
Effect on fetus:
Bile acids, cause a dose-dependent vasoconstrictive effect on isolated human placental chorionic veins. An abrupt reduction of oxygenated blood flow at the placental chorionic surface leading to fetal asphyxia may be an explanation for fetal distress and demise
What is the genetics of obstetric cholestasis?
Positive family history may be found in about 35% patients and 12% parous sisters are affected
Family studies suggest either AD or sex-linked dominant inheritance
What are three steps to diagnosing Obstetric Cholestasis?
- Typical history of pruritis without rash
- Abnormal LFTs
- Exclusion of other causes of itching and abnormal liver function
It is a diagnosis of exclusion
When diagnosing Obstetric Cholestasis, what investigations should you do, given that it is a diagnosis of exclusion?
- Liver USS
- Viral serology: Hep B, C. If clinical features of acute hepatitis: HAV, HEV, EBV, CMV
- Liver autoantibodies: anti-smooth muscle antibodies, anti-mitochondrial antibodies
What are the maternal risks of Obstetric Cholestasis?
Vitamin K deficiency due to malabsorption of fat-soluble vitamins
Possible increased risk of PPH
What are the fetal risks/ considerations with obstetric cholestasis?
Intrapartum fetal distress Passage meconium Spontaneous or iatrogenic preterm delivery IUFD Fetal intracranial haemorrhage
Magnitude difficult to determine
In obstetric cholestasis, the risk of stillbirth is related to the
Serum concentration of maternal bile acids