Test: Viral Hepatitis- 2 - NEET PG MCQ

Worldwide, chronic HBV infection impacts 350-400 million individuals, with the prevalence of the disease differing across geographical areas, ranging from 1-20%.

The World Health Organization (WHO) approximates that around 3% of the global population has been infected with HCV, leading to over 170 million chronic carriers who face an increased risk of developing liver cirrhosis and/or liver cancer.

• The most prevalent cause of chronic hepatitis is hepatitis C.
• However, the carrier stage is observed more frequently with hepatitis B.

Genotyping plays a significant role in forecasting the probability of treatment response and its duration. Patients exhibiting genotypes 1 and 4 typically undergo treatment for 12 months, while a treatment period of 6 months is adequate for other genotypes. Genotyping can be conducted through various methods:

• Direct sequence analysis
• Reverse hybridisation with genotype-specific oligonucleotide probes
• Restriction fragment length polymorphisms (RFLPs)

• This is with the important exception of patients with precore mutations who are unable to produce HBeAg.
• Its main clinical significance lies in serving as a marker of relative infectivity.
• In cases of self-limiting HBV infections, HBeAg becomes undetectable shortly after the peak rise in aminotransferase activity, prior to the loss of HBsAg.
• Subsequently, anti-HBe becomes detectable, which corresponds with a phase of reduced infectivity.

The mother of the infant is a carrier of hepatitis B, which means she has the virus in her blood. In this case, her hepatitis B serological profile is likely to show both HbsAg and HbeAg positivity.
This indicates that the virus is actively replicating, which increases the risk of transmission to the child. The presence of HbeAg suggests a higher viral load, making it more likely that the mother can pass the virus to her infant during childbirth.

• HbsAg confirms the presence of the virus.
• HbeAg indicates active viral replication.

In summary, the mother’s profile would show both HbsAg and HbeAg positivity, which is significant for understanding the infant's condition.

• The chances of sexual and perinatal transmission have been estimated to be <5%, well below comparable rates for HIV and HBV infections.
• HCV potentially can be transmitted sexually and perinatally; however, both of these modes of transmission are inefficient for hepatitis C.

The following infants are classified as 'high-risk' and should be administered both the vaccine and HBIG:

• Mother is HBsAg seropositive and HBeAg positive.
• Mother is HBsAg seropositive and HBeAg/anti-HBe negative.
• Mother is HBsAg seropositive and e markers are unavailable.
• Mother has acute hepatitis B during pregnancy.
• Mother is HBsAg seropositive and the infant is born weighing 1500g or less.

Hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg), which indicates infectivity, are the initial markers detectable in the serum during acute illness. Following these, hepatitis B core antibody (anti-HBc) immunoglobulin M (IgM) becomes identifiable.

Hepatitis B has an increased likelihood of being spread through blood transfusions.

Chronic hepatitis A is not present, and there is no state of being a carrier.

Because HBcAg is located within cells and, when present in the serum, is enclosed within an HBsAg coat, naked core particles do not circulate in the serum. Consequently, HBcAg is not typically detectable in the serum of individuals with HBV infection. In contrast, anti-HBc is easily identifiable in serum, starting within the initial 1-2 weeks after the emergence of HBsAg and appearing before detectable levels of anti-HBs by several weeks to months.

The patient's early symptoms in the prodromal phase comprise:

• Low-grade fever
• Nausea
• Vomiting
• Reduced appetite
• Abdominal pain

Older children and adults are more inclined to experience discomfort in the right upper quadrant. In young children, diarrhoea may arise, whereas constipation is more prevalent among adults. If jaundice, dark urine, and light-coloured stools occur, they typically manifest several days to a week following the emergence of systemic symptoms. Anicteric infections frequently occur in young children.

Serum albumin has a half-life of 21 days. Levels can remain normal in cases of fulminant hepatic failure, and it will take time for them to decrease.

Granulomatous hepatitis can lead to pyrexia of unknown origin, with granulomas detected via CT scan or abdominal ultrasound. It is linked to infections such as:

• tuberculosis
• cat scratch disease
• blastomycosis
• histoplasmosis

Hepatitis E is the primary cause of viral hepatitis in India, Asia, and Africa. Harrison notes that one-third of the global population seems to be affected.

The term Dane particle is specifically associated with the Hepatitis B virus (HBV). It is a crucial component of the virus, serving as a marker for the infection. Understanding its role is important for diagnosing and managing Hepatitis B.

Occult hepatitis B is characterised by the detection of HBV DNA in the serum or liver without the presence of HBsAg. Typically, the serum HBV level is below 10 copies/ml. This form of HBV infection has been identified in:

• Patients with hepatocellular carcinoma (HCC)
• Individuals with a history of past HBV infection
• Those suffering from chronic hepatitis C
• People lacking HBV serological markers

Cross-reactivity involving viral antigens (HCV NS3 and NS5A) and host autoantigens (cytochrome P450 2D6) has been proposed to clarify the link between hepatitis C and a particular group of patients who exhibit autoimmune hepatitis along with antibodies targeting liver-kidney microsomal (LKM) antigen.

Extra-hepatic manifestations of hepatitis C
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The virus that most commonly leads to chronic liver disease is the Hepatitis B virus (HBV). This virus is highly infectious and can be transmitted through contact with infected bodily fluids, such as blood and semen.
Key points about HBV include:

• It can cause both acute and chronic hepatitis.
• Chronic infection can lead to severe liver complications, including cirrhosis and liver cancer.
• Vaccination is available and effective in preventing HBV infection.

In comparison, other viruses like Hepatitis A and E do not typically lead to chronic infections. Hepatitis C (HCV) can also cause chronic disease, but it is less common than HBV.