1. What is Hepatitis? General: inflammation of liver parenchyma cells
Worst case: life threatening liver cirrhosis, liver failure and/or liver cancer

2. Normal Liver
Balloon Degeneration

3. Piecemeal Necrosis
Cell Dropout

4. Causes of hepatitis? Viral hepatitis
Primary: drug induced hepatitis, viral hepatitis
Secondary: syphilis, T.B
Viral hepatitis
Hepatitis A virus (picornovirus)
Hepatitis B virus (hepadnavirus)
Hepatitis C virus (flavivirus)
Hepatitis D, E, F, G viruses and non A-G
Epstien-Barr virus
Cytomegalovirus
Yellow fever virus
Infectious mononucleosis

5. Hepatitis A Virus -HAV-
The Facts
Picornaviridae, SSRNA, non enveloped
Destroyed by autoclaving, boiling, dry heat
Oral-fecal transmission
Occurs as epidemic
i.p 2-7 wks, mild jaundice, hepatospleenomegaly
No carrier state
Recovery within 2 months with solid immunity

6. HAV viruses
27nm diameter

7. Diagnosis and treatment
ELISA for HAV antibodies
Treat complicated case with Ig.
Prevention: decontaminate utensiles, cloths, water
Vaccination to prevent spread of disease

8. HEPATITIS B DNA and RNA (Hepadnaviruses) 3 forms of HBV in blood
small 22 nm (spherical
200 nm (filamentous)
Dane particle 42 nm
(spherical) infectious

9. Viral antigens hepatocytes HBs Ag Abs are protective blood HBe Ag
Abs are not protective
HBc Ag
Abs not protective
hepatocytes

10. Infection varies
Sub-clinical
Fulminant (hepatic necrosis)
Chronic carrier (hepatocellular carcinoma)

11. Transmission
Direct inoculation of blood or plasma (needle, transfusion)
Indirect precutaneous (infected serum) skin cut, abrassion
Adsorption of infected serum (mucosal surface)
Adsorption of potentially infectious secretion (saliva, vaginal, semen) to mucosal surface
oral-fecal …NO
Role of saliva… Negative except human bite

12. Incidence HBs is predominant in adults 21% oral surgeons
22% general surgeons
13-30 % dentists
significant of HBs is carrier up to 10% in HBs infections

15. Interpretation of serological markers
+HBs Ag: carrier and infectious
persist for 6 months acute
persist for year carrier
Anti HBs : recovery and immunity
vaccination
HBe Ag: Acute disease of high infectivity
if persist chronic liver damage
Anti HBe: partial recovery from infection
HBc Ag: present in liver
Anti HBc: Active (recent infection)

16. Typical Serological Courses of Infection
Symptoms
HBeAg
anti-HBe
Total anti-HBc
IgM anti-HBc
anti-HBs
HBsAg 4 8 12 16 20 24 28 32 36 52
100
Weeks after Exposure
Tite
Acute Hepatitis B Virus Infection with Recovery
Typical Serological Courses of Infection
HAV Infection
Fecal
HAV
Symptoms 1 2 3 4 5 6 12
Total anti-HAV
Tite
ALT
IgM anti-HAV
Months after exposure
IgM anti-HBc
Total anti-HBc
HBsAg
Acute (6 months)
HBeAg
Chronic (Years)
anti-HBe 4 12 24 36 52
Years
Weeks after Exposure
Titer
Progression to Chronic HBV Infection 9

17. Great risk to Dentist Known and unknown carriers
High risk patients include:
Jaundice (6 months), Blood therapy (hemophilia and thalassemia), chronic renal failure, multiple blood transfusion, addicts and homosexual
Prevention: Engerix B vaccine (subunit)
0, 1, 6, booster after one year

18. HEPATITIS C
RNA Chiron 1988
Transmition: post-transfusion, associated with hepatocellular carcinoma
Diagnosis: ELISA for detection of Anti HCV
Dental implication: lichen planus, oral malignancy, saliva contains HCV, Needle stick is common way of transmission

19. HEPATITIS D Defective RNA requires HBs for function
Occurs as coinfection with HBV
Transmitted parenterally
Diagnosis by ELISA
bad prognosis - higher incidence of liver necrosis, mortality

20. HEPATITIS E RNA (Calicivirus) Transmission: fecal/oral
Disease: 3-6 week incubation, abrupt onset, mild except if pregnant, 20% fatality rate
Jaundice: unknown
Chronic: no

21. 1996, transmitted through blood cause mild disease, present in saliva
HEPATITIS F: post transfusion
HEPATITIS G:
1996, transmitted through blood
cause mild disease, present in saliva
Transfusion transmitted virus(TTV)
Post transfusional hepatitis, non envelop, ss RNA (parvo virus)