VIRAL HEPATITIS Poljak Mario
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VIRAL HEPATITIS THE CAUSATIVE AGENTS, DIAGNOSIS AND MONITORING OF CHRONICALLY INFECTED PATIENTS Poljak Mario Institute of Microbiology and Immunology Medical Faculty of Ljubljana, Slovenia VIRAL HEPATITIS THE CAUSATIVE AGENTS, DIAGNOSIS AND MONITORING OF CHRONICALLY INFECTED PATIENTS PRIMARY hepatitis A virus hepatitis B virus hepatitis C virus hepatitis D virus hepatitis E virus SECONDARY Epstein-Barr virus cytomegalovirus herpes simplex viruses varicella-zoster virus coxcackieviruses adenoviruses rubella virus measles virus mumps virus hepatitis viruses A, B, C, D, E A, E B, C, D • only acute hepatitis, NO chronic disease • usually mild clinical course • life-long immunity? Hepatitis A virus - nonenveloped - single-stranded RNA virus - icosahedral capsid, 27 nm - family Picornaviridae - genus Hepatovirus - linear positive-strand RNA, 7.5 kb Hepatitis A diagnosis Anti-HAV total Anti-HAV IgM Hepatitis A Vaccination • Several inactivated and attenuated vaccines available • Two injections (0 and 6 - 12 month) • Antibody titer 10 - 100 fold higher after natural infection compared to vaccination • Lifelong immunity after vaccination is anticipated but has to be proven Hepatitis E virus - nonenveloped - single-stranded RNA virus - linear positive-strand RNA, 7.5 kb - family Caliciviridae - “hepatitis E-virus like” genus Hepatitis E diagnosis Anti-HEV IgG Anti-HEV IgM parenterally transmissible hepatitis viruses B, C, D HIV HBV TRANSMISSION TRANSMISSION HCV TRANSMISSION 1/10,000,000 1/1,000,000 1/100,000 1/10,000 1/1,000 1/100 TUNDERBOLT FATAL MURDER CAR DEATH DUE TO DEATH AIRPLANE DEATH ACCIDENT UNEXPECTED ACCIDENT DEATH DRUG ADVERSE REACTION IN HOSPITAL Safety of injections Estimated total burden of infection 8-16 million hepatitis B cases per annum attributable to unsafe 2-4.5 million hepatitis C cases injection practices 75.000-150.000 HIV infections Estimated annual public health 26 millions of years of life cost d cost generated by unsafe irect med. cost of USD 535 M injection practices Estimated annual deaths due to 1.3 million deaths unsafe injection practices WHO Bulletin, 2002 Hep C Hep B CIRRHOSIS Hep D 30 20 % 10 FIBROSIS 0 0 5 10 15 20 Years Liver transplantation in Europe (2004) l 59% hepatitis C l 28% hepatitis B l 7% hepatitis D Prevalence of HBV carriers Percentage long-term HBV carriers (350 million long-term carriers): < 2% - Low 2-7% - Intermediate > 8% - High Hepatitis B virus - partially double-stranded DNA virus that replicates through an RNA intermediate - family Hepadnaviridae, genus Orthohepadnavirus - circular partially double-strand DNA, 3.2 kb Hepatitis B – “serology” “markers” ü HBsAg ü anti-HBs (quantitative) ü anti-HBc total antibodies ü anti-HBc IgM ü HBeAg ü anti-HBe quantitative measurement of HBV DNA = HBV DNA viral load r = 0.60, p=0.001 8,8 8,4 Poljak M, Marin IJ, Seme K, Brinovec V, 8,0 Matičič M, Meglič-Volkar J. Second- generation Hybrid capture test and Cobas Amplicor 7,6 Monitor test generate highly correlated hepatitis B virus DNA levels. 7,2 J Virol Methods 2001; 97: 165-9. 6,8 Hybrid-Capture log HBV DNA (copies/ml) 6,4 6,0 6,4 6,8 7,2 7,6 8,0 8,4 8,8 9,2 Marin IJ, Poljak M, Seme K, Meglič-Volkar J, Amplicor log HBV DNA (copies/ml) Matičič M, Lešničar G, Brinovec V. Comparative evaluation of semi-automated Cobas Amplicor Hepatitis B Virus Monitor Test and manual microwell 10 plate-based Amplicor HBV Monitor Test. r = 0.976; p < 0.0001 9 J Clin Microbiol 2001; 39: 758-61. 8 7 Marin IJ, Poljak M, Seme K, Brinovec V, Matičič M, 6 Meglič-Volkar J, Lešničar G, Gradišek P. Comparative evaluation of three commercial assays for 5 quantitative measurement of log HBV DNA (copies/ml) hepatitis B virus DNA in serum samples. Hybrid Capture II HBV DNA Test 4 Hepato-Gastroenterol 2002; 49: 1390-1394 3 3 4 5 6 7 8 9 10 11 Cobas Amplicor HBV Monitor log HBV DNA (copies/ml) quantitative measurement of HBV DNA = HBV DNA viral load pg/ml copies/ml IU/ml Diagnosis of HBV infection Acute hepatitis B HBV DNA detection or quantification is not necessary for the diagnosis of acute hepatitis B, which is based on serological testing Diagnosis of HBV infection Problematic samples detection of HBV DNA useful in resolving diagnostic uncertainties following serological testing for markers of HBV infection that are caused by HBV genetic variations isolated anti-HBc positivity isolated HBsAg positivity simultaneous HBsAg and anti-HBs positivity HBsAg NEGATIVE anti-HBs NEGATIVE anti-HBc total POSITIVE anti-HBc IgM NEGATIVE HBe-Ag NEGATIVE anti-HBe NEGATIVE anti-HBc - alone status anti-HBc - alone status HBV DNA !!!!! HBsAg POSITIVE anti-HBs NEGATIVE anti-HBc total POSITIVE anti-HBc IgM NEGATIVE HBe-Ag NEGATIVE anti-HBe POSITIVE HBeAg-negative patient “inactive HBsAg carrier” HBeAg-negative chronic hepatitis HBeAg-negative patient “inactive HBsAg carrier” presence of HBsAg in serum without HBeAg more than 6 months without aminotransferase elevations and with HBV DNA levels less than 105 copies/ml HBeAg-negative chronic hepatitis presence of HBsAg in serum without HBeAg more than 6 months with elevated aminotransferases and/or with HBV DNA levels more than 105 copies/ml Disease severity L J Viral load Hepatitis B treatment FDA approved • interferon α-2b (1992) • lamivudine (1998) • adefovir (2002) • entecavir (2005) • pegylated interferon α-2a (2005) Treatment of HBV infection Decision to treat Selection of optimal therapy Treatment monitoring Prevention of Hepatitis B • HBV infection can be prevented in non-infected individuals by vaccination with HBV vaccine • series of 3 injections at 0, 1 and 6 months • vaccination is effective in 90-95% of recipients Recommendations for post-exposure vaccination • infants born to HBsAg+ mothers or to mothers who had acute hepatitis B during pregnancy • healthcare workers after needlestick injury involving blood from a HBV infected patient • sexual partners of individuals with HBV infection Hepatitis D virus - defective RNA virus - infections only in HBV infected patients - enveloped single-stranded RNA virus - genus Deltavirus - resembles plant viroids HBV HDV Hepatitis D diagnostic methods HbsAg + anti-HDV total antibodies anti-HDV IgM antibodies HDV Ag HDV RNA Hepatitis C virus - enveloped single-stranded RNA virus - family Flaviviridae, genus Hepacivirus - linear positive-strand RNA, 9.4 kb Detection of HCV markers during window phase following infection EIA 3.0 EIA 2.0 EIA 1.0 0 70 80 150 (DAYS) Hepatitis C diagnostic pathway anti-HCV screening test Hepatitis C diagnostic pathway anti-HCV screening test anti-HCV confirmatory test NIH Consensus Statement Management of Hepatitis C June 2002 Hepatology 2002; 36: S3-S20 anti-HCV screening test anti-HCV screening test negative anti-HCV screening test negative no HCV infection anti-HCV screening test negative positive no HCV infection anti-HCV screening test negative positive no HCV infection qualitative NAT anti-HCV screening test negative positive no HCV infection qualitative NAT negative anti-HCV screening test negative positive no HCV infection qualitative NAT negative anti-HCV confirmation or qualit. NAT after 3-6 months ?? anti-HCV screening test negative positive no HCV infection qualitative NAT negative positive Envelope Proteins HCV Core Protein (HCV Ag) HCV RNA Hepatitis C diagnostic pathway qualitative NAT positive 70 60 50 40 30 20 10 Sustained virologicSustained response 0 IFN CS-IFN IFN/RIB PEG-INF PEG-INF/RIB Therapy Hepatitis C diagnostic pathway qualitative NAT positive if therapy considered end of treatment response (ETR) sustained viral response (SVR) early viral response (EVR) Early viral response (EVR) • a minimum 2 log decrease in viral load during the first 12 weeks of treatment is predictive of sustained viral response (SVR) in patients with genotype 1 • patients who fail to achieve an EVR at week 12 of treatment have only a small chance of achieving an SVR even if therapy is continued for a full year • treatment need not be extended in these patients NIH Consensus Statement, Management of Hepatitis C, June 2002 Virological monitoring algorithm for patients with chronic hepatitis C on treatment GBV-C Virus / Hepatitis G virus Prevalence of GBV-C RNA Blood donors 0 - 2.3 % Haemophiliacs 8 - 38% Haemodialysis patients 15 - 57% IVDUs 16 - 38% p value, p > 0.01 p value, p > 0.01 p = please be pathogenic GBV-C Virus/Hepatitis G virus • most infections asymptomatic, transient, self-limiting, with slight or no elevation of ALT levels • majority of cases resolve after loss of serum RNA with a concomitant appearance of anti-E2 antibodies • infection with GBV-C doesn’t affect a clinical course in patients with hepatitis A, B, or C GBV-C or Hepatitis G virus • virus in search of a disease (Pessoa & Wright) • human orphan virus (Theodore & Lemon) ) • accidental tourist (Miyakawa & Mayumi Xiang J, et al. Effect of confection with GB virus C on survival among patients with HIV infection. N Engl J Med 2001; 345: 707-14. Tillmann HJ et al. Infection with GBV-C and reduced mortality among HIV-infected patients. N Engl J Med 2001; 345: 715-24. GBV-C as a therapeutic approach for HIV? hepatitis viruses A, B, C, D, E .