CAUSE:
1. Hepatitis A virus (RNA)
2. Hepatitis B virus (DNA)
3. Delta Hepatitis (D virus)
4. Hepatitis C and E viruses
Hepatitis A - RNA
This is caused by Hepatitis A virus which is RNA virus. it belongs to picorna family. The incubation period is 30 days.
Route of transmission is feco-oral route
Another factor responsible for Hepatitis A is overcrowding and poor sanitation facilities.
Prevention can be done by improving the social and unhygienic condition.
Hepatitis B - DNA
Caused by Hepatitis B virus which is DNA virus. It belongs to hepadeha family. Incubation period is 90 days. Route of transmission is parenteral route. (Infected blood, infected blood products, use of contaminated needles, needle sharing, IV drug abuse, tattooing, mother to child transmission possible, sexual intercourse.)
Hepatitis B has a carrier state unlike Hepatitis A
Hepatitis B can be prevented by active immunization with hepatitis B vaccine followed by booster dose at 1 and 6 months. This provides 95% protection. In cases of accidental exposure to hepatitis B positive blood, the victime could be given hyperimmune serum globulin within 24 hours of exposure.
Serology of Hepatitis B
In all patients infected with Hepatitis B the first to rise is HBS antigen
Second to rise is HBE antigen (envelope antigen) indicates high rate of multiplication of hepatitis B virus in patients liver cells.
Next to rise is antibody to hepatitis B core antigen - indicates chronic infection.
Fourth to rise is antibody to envelope antigen. This indicates decrease in the rate of multiplication of Hepatitis B virus in patient's heptocytes.
Last/ fifth to appear is antibody to surface antigen. This only indicates that the patient has suffered from Hepatitis B virus infections at some point of time.
Hepatitis B core antigen only appears inside the liver. It does not appear in blood Hepatitis B core antigen cannot be detected in affected patient's serum.
Hepatitis D
Caused by Hepatitis D virus. It is a defective RNA virus. It has no independence existence Delta (D) virus requires hepatitis B virus for its expression and multiplication Delta virus can only infect a person when he is already having Hepatitis B virus infection. This is called co-infection. Hepatitis D virus can also infect a person who is already having Hepatitis B virus antibodies i.e. a carrier of hepatitis B virus. This is called a super infection Route of transmission is pareuteral (I.V) This also has a chronic carrier state like Hepatitis B .
Hepatitis C and E
Incubation period 40 days.
Route of transmission
Hepatitis C: parenteral
Hepatitis E: Feco-oral
Both these have carrier state
BOth are RNA viruses
PATHOGENESIS OF VIRAL HEPATITIS:
1. Presence of shrunken apeptotic Hepatocytes called as couoncil-man bodies
2. TRIADITIS
3. LOBULITIS
4. massive necrosis of the hepatocytes
Clinical Features:
In viral hepatitis pro dormal symptoms are present before the onset of Jaundice. This is usually present for 7 - 10 days, also known as anichteric phase.
1. Fever
2. Chills
3. Anorexia
4. Malaise
5. Headache
6. Distaste of food
7. Diarrhoea
8. Nausea
9. vomiting
The second phase is cholestatic phase/ Icteric phase here the liver is enlarged and tender clincial jaundice is present (yellowish discolouration of eyes and urine)
stool becomes pale
2. The third phase is Recovery phase. Here patients symptoms improve, Appetite improves. GI symptoms subsides, Jaundice decreases, liver size decreases to normal size. Stools and urine becomes normal among all viral hepatitis, Worst prognosis is hepatitis B and best is Hepatitis A and E.
INVESTIGATIONS:
Total leucocyte count is decrease.
9 AST and ALT as liver damage
Urine shows bilirubinemia
serum bilirubin increase
increased clotting and prothrombine time ( no clotting factor 2, 7, 9, 10thsi is because liver is at fault)
Decreased serum glucose levels (as decreased gluconeogenesis)
SEROLOGICAL TESTS:
In Hepatitis A - Anti HAV
In Hepatitis B - Anti HBs, Anti HBc, Anti HBe,
In Hepatitis D - Anti HDV
In Hepatitis C - Anti HCV
COMPLICATIONS:
Fulminant hepatic failure
Chronic hepatitis
Cirrhosis of liver
Hepatocellular carcinoma
TREATMENTS:
1. Rest ( bed rest is prodromal and cholestatic phase)
2. IV fluids as cannot take meals and is loosing a lot of fluids
3. Increased nutritious diet at of 300- 3500 kcal/day ( increased protein intake in diet)
4. Strict avodiance of hepato - toxic drugs liek ATT, oral contraceptive pills alcohol
5. SILYMARIN/ UMARIN: this is a recently found drug which happens to be hepato- protective, owing to it's anti oxidant activity.
