Hepatitis - B. Pharma 2nd Semester Pathophysiology notes pdf





       Structure of HBV




At the end of this lecture, students will be able to –

       Identify the symptoms of hepatitis

       Describe the structure of HBV

       Explain different stages of hepatitis


       Inflammation of liver

       Results in damage to hepatocytes with subsequent cell death

Etiology of hepatitis

       Viral infections – Hepatitis A, B, C, D, E ; Epstein barr virus, yellow fever virus, cytomegalo virus & herpes virus

       Autoimmune chronic hepatitis

       Toxins , Alcohol

       Drugs used for the treatment of tuberculosis e.g. Isoniazid

Symptoms of hepatitis

Initial symptoms

Final symptoms

Hepatic symptoms are flu like


Mild fever, Chills

Dark urine


Pale faeces containing puss cells

Nausea, Vomiting, Diarrhoea


Anorexia, Fatigue

Enlargement of spleen

Slight abdominal pain


Aching of joints

Dizziness, Drausiness, circulation problem

Types of hepatic viruses

Name of virus


Mode of spread

Hepatitis A virus (HAV)



Hepatitis B virus (HBV)


Parenteral, Sexual contact, Blood transfusion, Babies born to HBV infected mothers

Hepatitis C virus (HCV)


Parenteral transmission, IV drug abuse, needle sharing

Hepatitis D virus (HDV)


Super infection

Hepatitis E virus (HEV)


Transmitted enterically

Hepatits G virus (HGV)


Parenterally transmitted hepatotropic virus

Structure of HBV

       Only DNA containing virus

       Belongs to group ‘hepadnaviridae’

       Diameter- 42 nm; incubation period is 6-8 weeks

       Comprises of core and a capsule

       Core consists of DNA & DNA polymerase

       Core is surrounded by markers

      Hepatitis B core antigen (HBc Ag)

      Hepatitis B envelope antigen (HBe Ag)

      Hepatitis B  surface antigen (HBs Ag)

Mode of transmission of Hepatitis

       Present in all body secretion

       A close contact with an infected person spreads the disease

       By blood transfusion

       Not through fecal matter

Stages of hepatitis (Assessed by different markers)

Stage 1

       HBs Ag is identified in asymptomatic phase

       It appears even before the onset of a disease

       Reaches the peak level during disease stage

       The counts become less with in 3-6 months

Stage 2

       HBe Ag, HBV DNA, DNA polymerase appears

       HBe Ag – indicates the progression of infection

       Continues viral replication

Stage 3

       IgM and anti HBc is detected

       Ab is identified just before the onset of symptoms

       After several months of infections IgG and anti HBc

Phases of HBV infection

Proliferative phase

       Shows the presence of symptoms

       DNA of HBV has accessory replicative chromosomes and forms virions

       HBs antigen binds with MHC class molecule and activated CD8+ T-cells

Integrative phase

       Viral DNA gets incorporated into the host genome

       Damage of hepatocytes  by activation of CD8+ T- cells

Types of Hepatitis

Acute hepatitis comprises of 4 phases

1. Incubation period –depends on type of virus

       HAV – 12 weeks

       HBV – 10 weeks

       HCV – 7 weeks

       HDV – 6 weeks

       HEV – 2-8 weeks

Patient does not show any signs or symptoms in incubation period

2. Symptomatic pre – icteric phase

       Non specific symptoms like fatigue, nausea, vomiting, weight loss, low fever, headache, muscle & joint aches, diarrhoea

3. Symptomatic icteric phase

       Yellow coloration appears

       Jaundice appears in 3rd stage

4. Phase of recovery

       Takes place depending upon the severity of infection

Chronic hepatitis

       Hepatic diseases remain for more than 6  months

       Inflammation & necrosis takes place

       Fatigue, Malaise, Lack of apetite, mild jaundice

       Symptoms are highly variable & not predictive in nature


       Hepatitis is inflammation of liver that results in damage to hepatocytes with subsequent cell death

       It may occur due to viral , autoimmune chronic hepatitis, Toxins, Alcohol and drugs

       HBV is main causative organism

       Types of hepatitis include acute and chronic

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