Viral Hepatitis Hugh B. Fackrell Filename: Hepatite.ppt 4/9/2015 1 Hepatitis Virus Outline 2 Definitions Classification Structure Multiplication Clinical manifestations Epidemiology Diagnosis Control Baron’s Web Site 4/9/2015 Hepatitis an ancient disease, the etiology has only recently (50 yrs.) been revealed. 4/9/2015 3 Hepatitis An inflammatory disease necrosis of hepatocytes mononuclear response destroys liver architecture Liver excretion of bile pigments such as bilirubin into the intestine is interrupted 4/9/2015 4 Bilirubin Bilirubin: greenish-yellow pigment accumulates in the blood and tissues Jaundice yellow tinge in the skin and eyes caused by bilirubin 4/9/2015 5 Types of Jaundice Pre hepatic: Hemolytic Jaundice normal feces, anemia, reticulocytes Hepatic: Hepatocellular Jaundice fecal fat, bilirubinuria, Alkaline phosphatase high, gamma globulins high Post Hepatic: Obstructive Jaundice fecal fat, bilirubinuria, alkaline phosphatase high 4/9/2015 6 Jaundice of the Newborn Premature infants bilirubin increases from birth peaks at one week caused by 1:excessive hemolysis 2:immature liver function 4/9/2015 7 Hepatitis symptoms 8 Swelling and tenderness of liver Jaundice -yellow tinge in the skin and eyes dark urine transaminase, alkaline phosphatase levels increased 4/9/2015 Viral Hepatitis Liver infection caused by several UNRELATED VIRUSES Inflammation and necrosis of the liver 50% of HAV & HBV are subclincal 4/9/2015 9 Hepatitis types Hepatitis A - HAV "infectious hepatitis" Hepatitis B - HBV "serum hepatitis" Hepatitis C - HCV non A, non B Hepatitis D - HDV Delta virus Hepatitis E - HEV similar to type “A” 4/9/2015 10 Hepatitis A “Infectious hepatitis” “Epidemic hepatitis” HAV 4/9/2015 11 Hepatitis A Clinical manifestations asymptotic or anicteric in children 3-5 week incubation period liver inflammation malaise - flu like symptoms self limiting low mortality 4/9/2015 12 Hepatitis A Structure Picornavirus Only one serotype Enterovirus type 72 27-29 nm icosahedral ssRNA 4/9/2015 13 Hepatitis A Host Defenses antibodies develop late in incubation period IgM within a week of dark urine peaks a week later lasts 40-60 days IgG after 14 IgM peaks 60-80 days lasts many years 4/9/2015 Hepatitis A Epidemiology Global distribution- underreported Fecal-oral route, person to person water Overcrowding & poor sanitation Infected food handlers common vector 4/9/2015 15 Annual Incidence Viral food borne diseases Norwalk-like viruses Total Viral food borne 30,883,391 23,000,000 Total Microbial food Rotavirus borne incidence 3,900,000 Astrovirus 38,629,64 3,900,000 Hepatitis A 83,391 CDC 4/9/2015 16 Hepatitis A Diagnosis Clinical manifestions Viral antigens Immunoelectron microscopy RIA ELISA Immune Adherence hemagglutination (old method) Viral antibodies 4/9/2015 17 Hepatitis A Control No specific control Improve hygiene and sanitation Human immunoglobulin 2 IU anti Hepatitis A /kg body weight HAV vaccines in clinical field trials 4/9/2015 18 Hepatitis B “Serum hepatitis” HBV 4/9/2015 19 Hepatitis B Clinical Manifestations typical viral hepatitis symptoms 4-26 week incubation period more severe than HAV CHRONIC PERSISTENT HEPATITIS CHRONIC ACTIVE HEPATITIS 4/9/2015 20 Hepatitis B Structure Hepadnavirus dsDNA, circular, 3200 nucleotides enveloped icosahedral virus 42 nm 4/9/2015 21 Australia antigen “Dane particle” small pelomorphic particles 20-22nm tubular forms excess viral capsids released into blood stream 4/9/2015 22 3 forms of HBV 4/9/2015 23 Dane Particles 4/9/2015 24 Hepatitis B Host Defenses Cell mediated Immunity important for recover in acute phase autoimmune liver damage in chronic infections Humoral Immunity not always protective HBsAg for Vaccines Interferon not 25 detected during infection exogenous application effective 4/9/2015 Hepatitis B Epidemiology Parenterally ie via blood, saliva, menstrual and vaginal discharges, semen and breast milk infected blood and blood products sexual contact perinatally from mother to child 4/9/2015 26 Hepatitis B Prevalence AREA Western Europe USA Eastern Europe USSR China Asia HBsAg 0.2-0.5% anti HBsAg 4-6% 2-7 % 20-55% 8-20 % 70-95% 4/9/2015 27 Hepatitis B Diagnosis Electron microscopy Viral DNA polymerase Viral DNA probes Serology 4/9/2015 28 Hepatitis B Serology Hepatitis B surface antigen- HBsAg 10 subtypes Hepatitis B core antigen- HBsCAg Soluble core associated antigen HBeAg Corresponding antibodies to each antigen occur 4/9/2015 29 Hepatitis B Control No specific control Passive Immunization HBV immunoglobulin 250-500 IU within 48 hours neonates of infected mothers -immediately after birth Active Immunization HBsAg 30 recombinant DNA in yeast 4/9/2015 HBV & Cancer 1. Transformation of the cell by virus 2. Helper virus if the transforming virus is defective 3. Co-carcinogen, chemical, cigarette smoke 4/9/2015 31 Transformed cells lose contact inhibition continue to divide form random aggregations can become invasive Not warts: Papovavirus 4/9/2015 32 Primary Hepatocellular Carcinoma Highest incidence: Central Africa Southeast China Pacific Islands, Borneo, Sarawak, Taiwan Icteric symptoms: jaundice, dark urine, pale stools Global 250,000- 1,000,000 deaths /year U.S.A. 5000 deaths / year 4/9/2015 33 Acute HBV & Cancer Acute Hepatitis B 90% 1% Resolution Fulminant Hepatitis Resolution Asymptomatic Carrier Chronic Active Hepatitis Chronic 50% Extrahepatic Disease Cirrhosis Hepatic Cell Carcinoma 4/9/2015 34 Hepatitis C HCV Non -A Non-B 4/9/2015 35 Hepatitis C Clinical Manifestations resembles HBV persistent carrier state 50% of patients have chronic liver damage associated with hepatocellular carcinoma 4/9/2015 36 Hepatitis C is probably caused by several different viruses 4/9/2015 37 Hepatitis C Epidemiology in USA causes 90% of post transfusion hepatitis Mother to infant transmission 4/9/2015 38 Hepatitis C Diagnosis C100-3 recombinant viral antigen anti c100-3 marker of chronic infection 4/9/2015 39 Hepatitis A HAV Hepatitis B HBV Hepatitis C HCV Structure RNA DNA HBV Cultured in cells yes no no Epidemiology endemic & epidemic endemic endemic Transmission oral/fecal, water & food blood/serum, close contact blood/serum, intimate contact 2-7 weeks 1-6 months 2-8 weeks fever, G-I tract disorder fever, rash, arthritis similar to HBV Jaundice 1 case in 10 common common Onset acute/short gradual/chronic acute/chronic not available yes not available yes yes yes Incubation period Symptoms Vaccine Diagnostic tests 4/9/2015 40 Hepatitis D HDV 4/9/2015 41 Hepatitis D Dependovirus, it is defective and cannot produce infection unless the cell is also infected with HBV. Viroid - a naked strand of RNA that enters the cell in piggy-back fashion. 4/9/2015 42 Hepatitis D Clinical Manifestations Dual infection is more severe than HBV fulminating hepatitis severe rapidly progressive hepatitis severe exacerbations 4/9/2015 43 Hepatitis D Structure 35-37 nm virus particle shares coat protein of HBV small RNA genome one serotype 4/9/2015 44 Hepatitis D Epidemiology hemophiliacs and IV drug users Contaminated blood and blood products 4/9/2015 45 Geographic distribution of HDV 4/9/2015 46 Hepatitis D Diagnosis Clinical manifestations Delta antigen Immunofluorescence RIA ELISA Anti delta antigen same as above 4/9/2015 47 Hepatitis E Virus 4/9/2015 48 Hepatitis E fecal/oral route predominantly found in developing countries but is world wide. symptoms similar to HAV but mortality 12% (ten times that of Hepatitis A). epidemics - India, Pakistan, Nepal, Burma, North Africa and Mexico. 4/9/2015 49