Serum Hepatitis or Hepatitis B
Hepatitis is a systemic viral infection with inflammation of liver and necrosis of liver cells which leads to clinical, biochemical and histological changes. It is major health problem throughout the world affecting several hundred millions of persons every year. It is responsible for large no. of morbidity and mortality both from acute infection & from its chronic complications. It is also known as 'viral hepatitis' and usually refers to disease caused by hepatitis virus A, B, C, D, E and other non-A non-B (NANB) viruses. Hepatitis A is also known as Infectious Hepatitis while Hepatitis B is known as Serum hepatitis. There is no known animal reservoir of serum hepatitis is seen sofar
Types of viruses responsible for viral hepatitis :
The different types of viruses responsible for viral hepatitis are as follows:
1. Hepatitis A virus (HAV) or infectious hepatitis
2. Hepatitis B virus (HBV) or serum hepatitis
3. Hepatitis C virus (HCV) or parenterally transmitted non A, non B hepatitis virus
4. Hepatitis Delta virus (HDV)
5. Hepatitis E virus or enterically transmitted non A, non-B hepatitis virus.
Hepatitis A and hepatitis E is transmitted from person to person by drinking or eating contaminated water and food or come in contact with materials having virus. Hepatitis B, C, and D are transmitted by percutaneous route.
Pathogenesis of Serum hepatitis :
Pathogenesis of serum hepatitis focuses attention only on the liver, but this is a generalised disease.
There is marked inflammatory changes in the stomach and small intestine mucosa causing marked anorexia at the onset of disease.
Renal biopsy shows oedema of glomeruli & tubules.
Haemopoietic system is also affected.
In severe cases, histological evidence of acute pancreatitis is seen on post mortem.
Multiplication of hepatitis virus occurs in the hepatic cells. Hepatic damage is not too much by the virus as by immune reactions against it.
Mode of transmitted and risk factors of Serum hepatitis :
Major route of transmission of hepatitis B virus (HBV) infection is by means of percutanious route which are as follows:
• Occur after intradermal, subcutaneous, intramuscular, intravenous injections
• Those receiving measles, mumps, or yellow fever inoculation
• Direct inoculation of blood or blood products obtained from a person infected with hepatitis B virus.
• Use of non disposable syringes & niddles without proper sterilisation.
• Use of shared razors.
• Tattoo niddles and dyes
• Ear piercing needles
• Organ transplantation and haemodialysis
• Intra-venous drug addicts
• Groups receiving frequent blood transfusion in case of Haemophilia are at high risk
• Health care workers frequently exposed to patient's blood like surgeons, pathologists, dentists, working in blood banks, dialysis units, hospital labs etc. are also at high risk
• Non-percutaneous spread is also known to occur in sexual contact with homosexual or heterosexual with a hepatitis B infection are at risk
• Other important mode of transmission of serum hepatitis infection is vertical spread from HBsAg carrier mothers to their infants in peripartum period.
• Caesarean section does not prevent Neonatal infection.
Though the serum hepatitis is not transmitted by breast feeding but it has been suggested that in the presence of a cracked nipple, contamination of mother's serum may occur leading to infection of disease in infants.
Incubation period of Serum hepatitis :
Incubation period of disease is defined as the period of infection to the onset of symptoms of disease. It is usually 70 to 80 days with a range of 45 to 180 days.
About 5 to 10 % of persons acutely infected with 'serum hepatitis' virus continue to have hepatitis B virus antigen in their serum for more than 6 months. These chronic carriers may be either asymptomatic or suffering from chronic serum hepatitis carrier state develops more often if infection occurs at a younger age, in males or in those with an immuno-deficiency.
Chronic infected persons have more 200 times long term risk of hepato-cellular carcinoma than normal population.
Symptoms of Serum hepatitis :
Symptoms of disease usually occur in two phases which are:
1. Pre-icteric phase: characterised by
• Anorexia and nausea of sudden onset. There is severe distaste of food and even mere the sight of food may cause nausea. The anorexia a and nausea usually disappear with the onset of jaundice.
• Dislike for smoking
• Some patients may complain dark coloured urine as the first symptom
• Mild to moderate fever which may subsides as the icterus appears
• Pain or discomfort in the upper abdomen due to stretching of liver capsule
Jaundice appears after 3-7 days of the pre-icteric phase. The diagnosis of the jaundice can be missed when patient is examined in a artificial or dim light. With the onset of jaundice, anorexia, nausea, vomiting and fever usually subsides & patient may have a sense of well being.
Signs of Serum hepatitis :
On clinical examination follow signs are seen:
• Pulse rate is slow, about 62-68/minute
• Enlarged liver (soft and tender & may be palpable 1-2 fingers below the right costal margin.
• The intercostals spaces over the liver are tender on light percussion
• Spleen is enlarge but not palpable
• Ascites is seen in malnourished patients & those who have previous history of jaundice
• Dark coloured urine is seen before the clinical appearance of jaundice. Morning urine sample as a rule is darker than subsequent day samples. During recovery, the urine colour becomes lighter and the morning sample being the last to show normal colour.
Diagnosis of Serum hepatitis :
Diagnosis of disease is done by thorough clinical examination and by Lab tests which are as follows:
Liver function Tests :
Total serum bilirubin level is more than 1 mg/dl during pre-icteric phase and up to 10-15 mg/dl at the height of moderate illness. Direct reacting bilirubin is always high.
Prothrombin activity of blood is decreased while prothrombin time is increased.
Serum glutamic oxalacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) are markedly raised in early stages of disease.
These enzymes are released due to necrosis of liver cells.
Serum alkaline phosphatase increases in cholestatic type of viral hepatitis.
Rise is serum alpha fetoprotein denotes the regenerative activity in the liver cells.
Haemopoietic system : Peripheral blood may show normal count or leucopenia with lymphocytosis.
ESR is raised
Bone marrow is depressed with diminished granulocytes, thrombocytopenia and aplastic anaemia.
Diagnosis of jaundice caused by different types of viruses (A, B, C, D, or E) is confirmed by identifying IgM antibody of that virus. This test is mainly performed for hepatitis B virus (IgM anti-HBc).
Complications of Serum hepatitis :
• Liver cirrhosis
• Hepato-cellular carcinoma
Prognosis of Hepatitis B :
Prognosis of disease is poor due to its complications.
Treatment of serum hepatitis :
There is no specific treatment of hepatitis B infection. The disease can only be prevented by restricting mode of transmission and risk factors. It is also prevented by immunization by hepatitis B vaccine.
Course of Hepatitis B infection is as follows :
• Virus may be eradicated.
• Healthy carrier: Patient may not reveal deranged liver function but HBsAg may present in the blood.
• Acute prolonged hepatitis may persist for few months only.
• Chronic hepatitis in which changes continue for more than 6 months. If chronic active hepatitis is present it may leads to cirrhosis, otherwise the disease may be benign i.e. chronic persistent hepatitis.
• Liver Cirrhosis.
• Liver carcinoma.