Viral Hepatitis Hugh B Fackrell Filename Hepatite ppt
Viral Hepatitis Hugh B. Fackrell Filename: Hepatite. ppt 1 12/5/2020
Hepatitis Virus Outline 2 þDefinitions þClassification þStructure þMultiplication þClinical manifestations þEpidemiology þDiagnosis þControl Baron’s Web Site 12/5/2020
Hepatitis þan ancient disease, the etiology has only recently (50 yrs. ) been revealed. 3 12/5/2020
Hepatitis þAn inflammatory disease -necrosis of hepatocytes -mononuclear response destroys liver architecture þLiver excretion of bile pigments such as bilirubin into the intestine is interrupted 4 12/5/2020
Bilirubin þBilirubin: greenish-yellow pigment accumulates in the blood and tissues þJaundice - yellow tinge in the skin and eyes -caused by 5 bilirubin 12/5/2020
Types of Jaundice þPre hepatic: Hemolytic Jaundice -normal feces, anemia, reticulocytes þHepatic: Hepatocellular Jaundice - fecal fat, bilirubinuria, Alkaline phosphatase high, gamma globulins high þPost Hepatic: Obstructive Jaundice -fecal fat, bilirubinuria, alkaline phosphatase high 6 12/5/2020
Jaundice of the Newborn þPremature infants þbilirubin increases from birth þpeaks at one week þcaused by -1: excessive hemolysis -2: immature liver function 7 12/5/2020
Hepatitis symptoms 8 þSwelling and tenderness of liver þJaundice -yellow tinge in the skin and eyes þdark urine þtransaminase, alkaline phosphatase levels increased 12/5/2020
Viral Hepatitis þLiver infection caused by several UNRELATED VIRUSES þInflammation and necrosis of the liver þ 50% of HAV & HBV are subclincal 9 12/5/2020
Hepatitis types þHepatitis A - HAV "infectious hepatitis" þHepatitis B - HBV "serum hepatitis" þHepatitis C - HCV non A, non B þHepatitis D - HDV Delta virus þHepatitis E - HEV similar to type “A” 10 12/5/2020
Hepatitis A “Infectious hepatitis” “Epidemic hepatitis” HAV 11 12/5/2020
Hepatitis A Clinical manifestations þasymptotic or anicteric in children þ 3 -5 week incubation period þliver inflammation þmalaise - flu like symptoms þself limiting þlow mortality 12 12/5/2020
Hepatitis A Structure þPicornavirus þOnly one serotype þEnterovirus type 72 þ 27 -29 nm icosahedral þ ss. RNA 13 12/5/2020
Hepatitis A Host Defenses þ antibodies develop late in incubation period þIg. M -within a week of dark urine -peaks a week later -lasts 40 -60 days þIg. G -after Ig. M -peaks 60 -80 days 14 -lasts many years 12/5/2020
Hepatitis A Epidemiology þGlobal distribution- underreported þFecal-oral route, -person to person - water þOvercrowding & poor sanitation þ Infected food handlers common vector 15 12/5/2020
Annual Incidence Viral food borne diseases þ Norwalk-like viruses þ Total Viral food borne 30, 883, 391 - 23, 000 þ Total Microbial food þ Rotavirus borne incidence - 3, 900, 000 þ Astrovirus - - 38, 629, 64 3, 900, 000 þHepatitis A -83, 391 16 CDC 12/5/2020
Hepatitis A Diagnosis þClinical manifestions þ Viral antigens -Immunoelectron microscopy -RIA -ELISA -Immune Adherence hemagglutination (old method) þViral antibodies 17 12/5/2020
Hepatitis A Control þ No specific control þImprove hygiene and sanitation þHuman immunoglobulin -2 IU anti Hepatitis A /kg body weight þHAV vaccines in clinical field trials 18 12/5/2020
Hepatitis B “Serum hepatitis” HBV 19 12/5/2020
Hepatitis B Clinical Manifestations þtypical viral hepatitis symptoms þ 4 -26 week incubation period þmore severe than HAV þCHRONIC PERSISTENT HEPATITIS þCHRONIC ACTIVE HEPATITIS 20 12/5/2020
Hepatitis B Structure þ Hepadnavirus þ ds. DNA, circular, 3200 nucleotides þenveloped icosahedral virus þ 42 nm 21 12/5/2020
Australia antigen “Dane particle” þsmall pelomorphic particles 20 -22 nm þtubular forms þexcess viral capsids released into blood stream 22 12/5/2020
3 forms of HBV 23 12/5/2020
Dane Particles 24 12/5/2020
Hepatitis B Host Defenses þCell mediated Immunity -important for recover in acute phase -autoimmune liver damage in chronic infections þHumoral Immunity -not always protective -HBs. Ag for Vaccines þInterferon -not detected during infection 25 -exogenous application effective 12/5/2020
Hepatitis B Epidemiology þParenterally ie via blood, saliva, menstrual and vaginal discharges, semen and breast milk þinfected blood and blood products þsexual contact þperinatally from mother to child 26 12/5/2020
Hepatitis B Prevalence AREA Western Europe USA Eastern Europe USSR China Asia 27 HBs. Ag 0. 2 -0. 5% anti HBs. Ag 4 -6% 2 -7 % 20 -55% 8 -20 % 70 -95% 12/5/2020
Hepatitis B Diagnosis þElectron microscopy þViral DNA polymerase þViral DNA probes þSerology 28 12/5/2020
Hepatitis B Serology þHepatitis B surface antigen- HBs. Ag - 10 subtypes þHepatitis B core antigen- HBs. CAg þSoluble core associated antigen HBe. Ag Corresponding antibodies to each antigen occur 29 12/5/2020
Hepatitis B Control þNo specific control þPassive Immunization - HBV immunoglobulin -250 -500 IU within 48 hours -neonates of infected mothers -immediately after birth þActive Immunization -HBs. Ag 30 -recombinant DNA in yeast 12/5/2020
HBV & Cancer 1. Transformation of the cell by virus 2. Helper virus if the transforming virus is defective 3. Co-carcinogen, chemical, cigarette smoke 31 12/5/2020
Transformed cells þlose contact inhibition þcontinue to divide þform random aggregations þcan become invasive Not warts: Papovavirus 32 12/5/2020
Primary Hepatocellular Carcinoma þHighest incidence: -Central Africa -Southeast China -Pacific Islands, Borneo, Sarawak, Taiwan þIcteric symptoms: -jaundice, dark urine, pale stools 33 þ Global 250, 000 - 1, 000 deaths /year þ U. S. A. 5000 deaths / year 12/5/2020
Acute HBV & Cancer Acute Hepatitis B 90% 1% Resolution Fulminant Hepatitis Resolution Asymptomatic Carrier Chronic Active Hepatitis Chronic 50% Extrahepatic Disease 34 Cirrhosis Hepatic Cell Carcinoma 12/5/2020
Hepatitis C HCV Non -A Non-B 35 12/5/2020
Hepatitis C Clinical Manifestations þresembles HBV þpersistent carrier state þ 50% of patients have chronic liver damage þassociated with hepatocellular carcinoma 36 12/5/2020
Hepatitis C is probably caused by several different viruses 37 12/5/2020
Hepatitis C Epidemiology þ in USA causes 90% of post transfusion hepatitis þMother to infant transmission 38 12/5/2020
Hepatitis C Diagnosis þC 100 -3 recombinant viral antigen þanti c 100 -3 marker of chronic infection 39 12/5/2020
Hepatitis A HAV Hepatitis B HBV Hepatitis C HCV Structure RNA DNA HBV Cultured in cells yes no no Epidemiology endemic & epidemic 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 Onset acute/short gradual/chronic acute/chronic not available yes yes Incubation period Symptoms Vaccine Diagnostic tests 40 12/5/2020
Hepatitis D HDV 41 12/5/2020
Hepatitis D þDependovirus, it is defective and cannot produce infection unless the cell is also infected with HBV. þViroid - a naked strand of RNA that enters the cell in piggy-back fashion. 42 12/5/2020
Hepatitis D Clinical Manifestations þDual infection is more severe than HBV þfulminating hepatitis þsevere rapidly progressive hepatitis þsevere exacerbations 43 12/5/2020
Hepatitis D Structure þ 35 -37 nm virus particle þshares coat protein of HBV þ small RNA genome þone serotype 44 12/5/2020
Hepatitis D Epidemiology þ hemophiliacs and IV drug users þContaminated blood and blood products 45 12/5/2020
Geographic distribution of HDV 46 12/5/2020
Hepatitis D Diagnosis þClinical manifestations þ Delta antigen -Immunofluorescence -RIA -ELISA þAnti delta antigen -same as above 47 12/5/2020
Hepatitis E Virus 48 12/5/2020
Hepatitis E þfecal/oral route þpredominantly found in developing countries but is world wide. þsymptoms similar to HAV but mortality 12% (ten times that of Hepatitis A). þepidemics - India, Pakistan, Nepal, Burma, North Africa and Mexico. 49 12/5/2020
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