VIRAL HEPATITIS كلية طب الاسنان 2017

Q: What are the main and common viral types that are responsible for hepatitis? A: The following are the main 5 types of viruses: 1. Hepatitis A virus(HAV) 2. Hepatitis B virus(HBV) 3. Hepatitis C virus(HCV) 4. Hepatitis D virus(HDV) 5. Hepatitis E virus(HEV)

What are other less common viruses that cause hepatitis What are other less common viruses that cause hepatitis? A: HGV, Epstein-Barr virus (EBV), cytomegalovirus (CMV), yellow fever virus, measles virus etc. Q: What are nucleic acid structures of the main 5 types of hepatitis viruses? A: HAV: RNA, HBV: DNA (also it is the largest virus in regard to its size) , HCV: RNA, HDV: RNA, HEV: RNA. All are RNA, except HBV.

Worldwide, how many people are infected with HBV Worldwide, how many people are infected with HBV? A: Around 450 - 500 million people are infected. Q: Worldwide, how many people are infected with HCV? A: Approximately 350 million people are infected.

If the patient discovered to have any of above viruses; what other virus is likely to be present in addition? A: In the presence of HBV always search for presence of HDV and HIV. In other viral hepatitis (A, C, E) also search for HIV especially in those with illegal drug using. Q: How HAV transmits or acquires? A: Fecal-oral is the principle method of HAV transmission (but occasionally through blood or saliva).

What are hepatitis C genotypes What are hepatitis C genotypes? A: There are 6 genotypes (G1, G2, G3, G4, G5, and G6). Their responses to treatment are differ.

Q: Mention the principle methods of HBV transmission: A: Mainly parenteral but not fecal-oral. 1. Blood and blood products especially in those with hemophilia. 2. Trans-sexual (vertical) from mother to baby. 3. Needle sharing by illegal drug users and also through unsterilized instruments e. g. dental instruments, dialysis machines, operative (surgical) instruments, endoscopes, etc.

Mention the principle methods of HCV transmission: A: Mainly parenteral but not fecal-oral and sexual (vertical) transmission is rare. 1. Blood and blood products. 2. Needle sharing by illegal drug users and also through unsterilized instruments e. g. dental instruments, dialysis machines, operative (surgical) instruments, endoscopes, etc.This is the principle method of transmission in western countries.

Note: All people born in 1945 – 1965 are tested routinely for HCV in USA and Europe; in addition all people who are receiving blood products before 1987 are also tested for HCV.

Q: What about vaccination in viral hepatitis Q: What about vaccination in viral hepatitis? A: Vaccination is available for HAV and HBV only but not for C, D, and E. Hepatitis D can be indirectly prevented by vaccination for B as it is incomplete virus and can't exist without the presence of HBV. Q: How long is the incubation period (IP) for viral hepatitis? A: HAV and HEV: Several weeks, while in HBV, HCV and HDV in several weeks to several months. HCV characterized by having the longest IP.

What are the main complications of viral hepatitis. 1 What are the main complications of viral hepatitis? 1. Acute liver failure in acute hepatitis especially in HBV or co-infection with HBV and HDV, This condition is rare in HAV and HEV except if HEV infects the pregnant women. 2. Change to chronic hepatitis: This is a feature of HBV, HDV and HCV but not in HAV or HEV. Chronic liver disease will lead to liver fibrosis and in about 15 – 20% will lead to liver cirrhosis. 3. Liver cancer: also called hepatoma or hepatocellular carcinoma (HCC). This is due to liver cirrhosis.

Q: Which one of following viruses has the greatest tendency for chronicity in adult? a. HBV. b. HCV. A: both can go to chronic stage but HCV in adult has the greatest tendency to do as > 70% of patients with HCV will go to chronic stage, while only 5-10% of HBV (adult acquired) go to chronic stage (except in cases of vertical transmission of HBV from mother to baby: High percentage with HBV will go to chronicity). Note: Chronicity means persistence evidence of hepatitis for > 6 months.

Q: Comment on clinical features of acute viral hepatitis Q: Comment on clinical features of acute viral hepatitis. A: Most cases are either asymptomatic and subclinical and not recognized by the patient or it may be discovered on routine blood test for liver function. For those who are symptomatic, the condition started after the IP with non-specific (or prodromal or flu-like illness) stage consists of fever, headache, fatigue, malaise and back ache. Nausea, vomiting and epigastric or right hypochondrial pain and dis-taste for coffee and cigarette are also common.

Q: Comment on clinical features of acute viral hepatitis Q: Comment on clinical features of acute viral hepatitis. A: Most cases are either asymptomatic and subclinical and not recognized by the patient or it may be discovered on routine blood test for liver function. For those who are symptomatic, the condition started after the IP with non-specific (or prodromal or flu-like illness) stage consists of fever, headache, fatigue, malaise and back ache. Nausea, vomiting and epigastric or right hypochondrial pain and dis-taste for coffee and cigarette are also common.

This stage followed by more specific features including jaundice, dark or brown colored urine, tenderness at right hypochondrial region with hepatosplenomegaly (enlarged liver and spleen). Cervical lymphadenopathy may also present.

Would you like to suggest some investigations for a patient with suspected viral hepatitis? A: 1. Liver function tests (LFTs) like s. bilirubin, liver enzymes (ALT and AST). 2. Serology for detection of viral types: Examples positive Anti-HAV antibodies (IgM) for diagnosis for acute HAV, HBsAg for diagnosis of HBV, and Anti-HCV antibodies for HCV. 3. Urine examination for bilirubin.

Is the specific treatment for HBV and HCV are differing Is the specific treatment for HBV and HCV are differing? A: Yes, because HBV is DNA while HCV is RNA. Q: What is interferon? A: Originally it is a natural substance in the body which plays a great role in defending the body against micro-organisms especially for viruses. It is used for treatment of both hepatitis B and C. It is associated with a lot of side effects and given in injection form.

Give examples of some oral medications for HBV Give examples of some oral medications for HBV? A: Lamivudine and Tenofovir. Q: Give example of an oral medication for HCV? A: Ribavirin. This medication is associated with serious side effects like hemolysis and is contra-indicated during pregnancy because it causes abortion and it is teratogenicity.

How I know as a dentist that patient had viral hepatitis How I know as a dentist that patient had viral hepatitis? And how I can protect myself or my patients from viral hepatitis? A. This may be difficult but it is necessary to see if the patient had jaundice or history of jaundice or history of hepatitis and also ask about his vaccination against viral hepatitis. B. It is very essential to protect yourself by wearing the protective cloths, gloves and masks during the work and all doctors must have vaccination against HBV.

C. Use disposable materials, instruments or devices for procedures whenever it is possible otherwise one should confine with the international guidelines for proper cleaning and sterilization of dental instruments and devices. D. If you have any suspicion about hepatitis, reference to physician is indicated.