Hepatitis B is a serious global health problem with over 2 billion people infected worldwide and 350 million suffering from chronic hepatitis B (CHB) infection. Infection can lead to chronic hepatitis, cirrhosis and hepatocellular carcinoma (HCC) accounting for 320,000 deaths per year. Numerous treatments are available, but with a growing number of therapies each with considerable trade-offs, the optimal treatment strategy is not transparent. This dissertation investigates the relative efficacy of treatments for CHB and estimates the health related quality of life (HRQOL) and health utilities of mild to advanced CHB patients. A systematic review of published randomized controlled trials comparing surrogate outcomes for the first year of treatment was performed. Bayesian mixed treatment comparison meta-analysis was used to synthesize odds ratios, including 95% credible intervals and predicted probabilities of each outcome comparing all currently available treatments in HBeAg-positive and/or HBeAg-negative CHB patients. Among HBeAg-positive patients, tenofovir and entecavir were most effective, while in HBeAg-negative patients, tenofovir was the treatment of choice. Health state utilities and HRQOL for patients with CHB stratified by disease stage were elicited from patients attending tertiary care clinics at the University Health Network in Toronto. Respondents completed the standard gamble, EQ5D, Health Utilities Index Mark 3 (HUI3), Short-Form 36 version-2 and a demographics survey in their preferred language of English, Cantonese or Mandarin. Patient charts were accessed to determine disease stage and co-morbidities. The study included 433 patients of which: 294 had no cirrhosis, 79 had compensated cirrhosis, 7 had decompensated cirrhosis, 23 had HCC and 30 had received liver transplants. Mean standard gamble utilities were 0.89, 0.87, 0.82, 0.84 and 0.86 for the respective disease stages. HRQOL in CHB patients was only impaired at later stages of disease. Neither chronic infection nor antiviral treatment lowered HRQOL. Patients with CHB do not experience lower HRQOL as seen in patients with hepatitis C. The next step in this area of research is to incorporate the estimates synthesized by the current studies into a decision model evaluating the cost-effectiveness of treatment to provide guidance on the optimal therapy for patients with HBeAg-positive and HBeAg-negative CHB.

Inclusion body hepatitis (IBH) has been occurring as an economically important, emerging disease of broiler chickens in several countries. Historically, IBH has been identified as a secondary disease, often associated with common immunosuppressive diseases. However, few studies have identified IBH as a primary disease with no apparent association with immunosuppressive diseases. The objectives of this study were to develop an animal model of IBH in commercial broilers, to demonstrate vertical transmission of fowl adenoviruses (FAdVs) in broiler breeders and to control IBH in broilers by vaccinating their parents with an inactivated FAdV vaccine. In order to develop an animal model of IBH in commercial broilers, fourteen-day old broilers were inoculated intramuscularly with 1x104 1x107 CCID50 of either FAdV x11a-like virus, two strains of FAdV-8a (FAdV-8a strain TR-59 and FAdV-8a strain T8-A) or FAdV-11strain 1047. Four days following FAdV inoculation, 5% - 15% mortality was observed and dead birds showed histologic lesions of hemorrhagic necrotizing hepatitis. This animal model reproduced the clinical disease, and pathological lesions of IBH that have been described in commercial broilers. In order to demonstrate vertical transmission of the FAdV, 35-week-old broiler breeders were inoculated with 1x106 CCID50 of either FAdV x11a-like virus, FAdV-8a strain TR-59, FAdV-8a strain T8-A or FAdV-11 strain 1047. Eggs from infected breeders were collected and hatched seven days post-inoculation. Clinical signs or mortality were not observed in parents; however broiler progeny derived from broiler breeders inoculated with FAdV-8a strain T8-A had 30% IBH mortality by seven days of age. The hexon gene loop 1 sequence of the virus isolated from affected broiler progeny showed 100% identity to FAdV-8a strain T8-A. In order to demonstrate protection of broilers against IBH by vaccination of their parents, four groups of broiler breeders were vaccinated with either FAdV-8a strain T8-A (2x107 or 2x104 CCID50) formulated with 20% oil-in-water emulsion, or FAdV x11a-like virus (2x107 or 2x104 CCID50) formulated with 20% oil-in-water emulsion at the age of 12 and 15 weeks. The control group was inoculated with 20% oil-in-water emulsion. Broiler progeny were challenged with FAdV-8a strain T8-A to study the immunoprotective effect of the vaccine. Although, survival of broilers following FAdV-8a strain T8-A challenge was not significantly different among vaccinated and non-vaccinated groups (P>0.05), immunoprotective effect was enhanced by the increase dose of FAdV antigens (P>0.05). Further studies are necessary to improve the vaccine efficacy to protect broilers against IBH.<p> In conclusion, the results of this study support the hypothesis that IBH in broilers in Canada is a vertically-transmitted primary disease with no known immunosuppressive involvement. The results also demonstrated that inactivated antigens of FAdV are able to partially protect broilers against IBH by vaccinating their parents. Further studies with different formulations, and priming the immune system of broiler breeders with live FAdV prior to vaccination with inactivated FAdV vaccines are necessary to improve the efficacy of inactivated IBH vaccine.

The recombinant Hepatitis B surface antigen vaccine inadequately protects those living with HIV from Hepatitis B virus infection. This study utilized saved serum samples from a retrospective cohort of persons with HIV and documented vaccine-induced HBsAb seroconversion to determine factors associated with persistence of protective levels of HBsAb (≥10mIU/ml). HBsAb levels fell below 10mIU/ml in 27% of the cohort after a median follow-up of 43 months. HIV viral load suppression (<50copies/ml) at the time of vaccination was the major factor associated with persistence of protective levels of HBsAb (OR 3.83, p <0.01). Among individuals who lost protective levels of HBsAb, booster doses of vaccine re-instated the development of protective levels of HBsAb. Delaying or repeating HBV vaccination until after suppression of HIV viral load is achieved should be considered HBV antibody levels should be followed over time and boosters given with loss of protective levels of HBsAb.

The recombinant Hepatitis B surface antigen vaccine inadequately protects those living with HIV from Hepatitis B virus infection. This study utilized saved serum samples from a retrospective cohort of persons with HIV and documented vaccine-induced HBsAb seroconversion to determine factors associated with persistence of protective levels of HBsAb (≥10mIU/ml). HBsAb levels fell below 10mIU/ml in 27% of the cohort after a median follow-up of 43 months. HIV viral load suppression (<50copies/ml) at the time of vaccination was the major factor associated with persistence of protective levels of HBsAb (OR 3.83, p <0.01). Among individuals who lost protective levels of HBsAb, booster doses of vaccine re-instated the development of protective levels of HBsAb. Delaying or repeating HBV vaccination until after suppression of HIV viral load is achieved should be considered HBV antibody levels should be followed over time and boosters given with loss of protective levels of HBsAb.

Hepatitis B is a serious global health problem with over 2 billion people infected worldwide and 350 million suffering from chronic hepatitis B (CHB) infection. Infection can lead to chronic hepatitis, cirrhosis and hepatocellular carcinoma (HCC) accounting for 320,000 deaths per year. Numerous treatments are available, but with a growing number of therapies each with considerable trade-offs, the optimal treatment strategy is not transparent. This dissertation investigates the relative efficacy of treatments for CHB and estimates the health related quality of life (HRQOL) and health utilities of mild to advanced CHB patients. A systematic review of published randomized controlled trials comparing surrogate outcomes for the first year of treatment was performed. Bayesian mixed treatment comparison meta-analysis was used to synthesize odds ratios, including 95% credible intervals and predicted probabilities of each outcome comparing all currently available treatments in HBeAg-positive and/or HBeAg-negative CHB patients. Among HBeAg-positive patients, tenofovir and entecavir were most effective, while in HBeAg-negative patients, tenofovir was the treatment of choice. Health state utilities and HRQOL for patients with CHB stratified by disease stage were elicited from patients attending tertiary care clinics at the University Health Network in Toronto. Respondents completed the standard gamble, EQ5D, Health Utilities Index Mark 3 (HUI3), Short-Form 36 version-2 and a demographics survey in their preferred language of English, Cantonese or Mandarin. Patient charts were accessed to determine disease stage and co-morbidities. The study included 433 patients of which: 294 had no cirrhosis, 79 had compensated cirrhosis, 7 had decompensated cirrhosis, 23 had HCC and 30 had received liver transplants. Mean standard gamble utilities were 0.89, 0.87, 0.82, 0.84 and 0.86 for the respective disease stages. HRQOL in CHB patients was only impaired at later stages of disease. Neither chronic infection nor antiviral treatment lowered HRQOL. Patients with CHB do not experience lower HRQOL as seen in patients with hepatitis C. The next step in this area of research is to incorporate the estimates synthesized by the current studies into a decision model evaluating the cost-effectiveness of treatment to provide guidance on the optimal therapy for patients with HBeAg-positive and HBeAg-negative CHB.

Hepatitis C is the most common blood-borne viral illness in the North America. Chronic hepatitis C infection may lead to cirrhosis of the liver, liver failure and liver cancer. In North America, injection drug use is the most important risk factor for infection and substance abusing populations are disproportionately affected by the disease. Antiviral therapy exists and approximately 50% of infected individuals can be cured. The aim of this thesis was to provide information to help clinicians and policy-makers minimize the impact of hepatitis C in substance abusers. The thesis is comprised of three studies. The first assessed the rate of progression to cirrhosis for those acquiring infection through injection drug use, using a meta-analysis of 44 studies from the published literature. We estimated that fibrosis progression occurs at a rate of 8.1 per 1000 person-years (95% Credible Region (CR), 3.9 to 14.7) corresponding to a 20-year cirrhosis prevalence of 14.8% (95% CR, 7.5 to 25.5). The second study measured the association between successful antiviral therapy and quality of life. We demonstrated that sustained responders to therapy had higher scores on the hepatitis-specific Medical Outcomes Survey Short-Form-36 (SF-36), Health Utilities Index Mark 2/3 (HUI2/3), and time-tradeoff (TTO) than treatment failures, an average of 3.7 years following antiviral therapy. The third study assessed rates of adherence to antiviral therapy and rates of sustained response in current or former iii substance abusers on methadone maintenance. We demonstrated that while use of illicit substances prior to therapy negatively affected adherence, rates of sustained response were comparable to non-substance abusing populations. Our work indicates the future burden of disease in current and former substance abusers, demonstrates that antiviral therapy can be successful in this population, and indicates that the benefits of successful therapy may extend beyond decreased disease burden to improved quality of life.

Antecedentes: El espectro clínico de la hepatitis alcohólica es muy variable, desde formas leves, que se recuperan fácilmente con la abstinencia enólica, hasta formas graves, en las que la tasa de mortalidad puede llegar hasta el 40%. En las últimas tres décadas se han ensayado numerosas estrategias terapéuticas, y los corticosteroides se han investigado ampliamente. A pesar de que algunos estudios no observan un efecto beneficioso, los corticoides continúan siendo el único tratamiento recomendado en la actualidad para los pacientes con hepatitis alcohólica grave. En estos pacientes malnutridos y anoréticos, el tratamiento nutricional también se ha mostrado eficaz. Sin embargo, no existen estudios que comparen la eficacia de ambos tratamientos en la hepatitis alcohólica grave. Por este motivo, hemos realizado este estudio aleatorizado sobre los efectos a corto y largo plazo del tratamiento con nutrición enteral o con corticoides en este grupo de pacientes.Métodos: Se aleatorizaron 71 pacientes (índice de Maddrey >32 y/o encefalopatía) para recibir 40 mg/día de prednisolona (n = 36) o nutrición enteral continua por sonda de alimentación (2000 Kcal/día) durante 28 días (n = 35), tras lo cual se siguieron durante un año o hasta su fallecimiento.Resultados: Los efectos secundarios relacionados con el tratamiento fueron similares en ambos grupos (5 en el grupo corticoides y 10 en el grupo enteral, NS). Ocho pacientes del grupo nutrición se retiraron del ensayo de forma prematura. La mortalidad durante el periodo de tratamiento de 28 días fue similar en ambos grupos (9/36 frente a 11/35, según la intención de tratar), pero, en los pacientes tratados con nutrición enteral, se produjo de forma más precoz (7 días de media frente a 23 días; p = 0,025). Las causas de muerte en ambos grupos durante este periodo se debieron a insuficiencia hepática grave e infecciones. Sin embargo, la mortalidad durante el periodo de seguimiento fue superior en los pacientes tratados con esteroides (10/27 frente a 2/24, según la intención de tratar; p = 0,04). Siete pacientes del grupo esteroides murieron en el primer mes y medio de seguimiento y, a diferencia del grupo enteral, las infecciones explicaron la muerte en 9/10 casos de este grupo.Conclusión: La nutrición enteral es similar a los corticoides en el tratamiento a corto plazo de la hepatitis alcohólica grave, aunque las muertes se producen de forma más precoz. Sin embargo, el tratamiento con corticoides se asocia con una mayor tasa de mortalidad en las primeras semanas después de finalizado el tratamiento, principalmente debido a infecciones. Por tanto, debería investigarse un posible efecto sinergístico de ambos tratamientos. / Background/Aim: The outcome of alcohol-induced hepatitis (AH) varies with its severity. Whereas patients with mild cases easily recover by stopping alcohol intake, the course of patients with severe disease is much poorer despite becoming abstinent, with a short-term mortality rate higher than 40%. A number of pharmacological approaches to the treatment of severe AH have been attempted in the last 3 decades, most of them with disappointing results. Despite several trials do not showed a beneficial effect of steroids, they are still the only recommended treatment for severe AH. Artificial nutritional has also been assayed for the treatment of AH, and some data suggest that could also be effective. We conducted a randomized trial comparing the short- and long-term effects of total enteral nutrition or steroids in these patients.Methods: A total of 71 patients (Maddrey index >32 and/or encephalopathy) were randomized to receive 40 mg/day prednisolone (n=36) or enteral tube feeding (2,000 Kcal/day) for 28 days (n=35), and were followed for one year or until death. Results: Side effects of treatment occurred in 5 patients on steroids and 10 on enteral nutrition (not significant). Eight enterally fed patients were prematurely withdrawn from the trial. Mortality during treatment was similar in both groups (9 of 36 vs. 11 of 35, intention-to-treat), but occurred earlier with enteral feeding (median 7 vs. 23 days; P = 0.025). Severe hepatic failure and infections were the main causes of death in both groups. Mortality during follow-up was higher with steroids (10 of 27 vs. 2 of 24 intention-to-treat; P = 0.04). Seven steroid patients died within the first 1.5 months of follow-up. In contrast to total enteral nutrition (TEN), infections accounted for 9 of 10 follow-up deaths in the steroid group. Conclusions: Enteral feeding does not seem to be worse that steroids in the short-term treatment of severe alcohol-induced hepatitis, although death occurs earlier with enteral nutrition. However, steroid therapy is associated with a higher mortality rate in the immediate weeks after treatment, mainly because of infections. A possible synergistic effect of both treatments should be investigated._

La tesi analitza, des de la perspectiva d'un cas concret, la tragèdia que assolà a tots els països avançats tecnològicament durant la dècada dels vuitanta amb el virus d'immunodeficiència humana (VIH) i dels noranta amb el virus de l'hepatitis C (VHC), els diversos mecanismes de què gaudeixen les víctimes per a aconseguir rescabalar-se de danys, així com les relacions que es donen entre aquestes diferents institucions. El treball s'estructura en tres grans apartats, en els quals s'analitza, en primer lloc, la tragèdia coneguda com «el cas de la sang contaminada»; en segon lloc, la responsabilitat civil derivada del contagi del VIH o del VHC per causa de transfusions o productes sanguinis; i, finalment, els ajuts públics establerts pels poders per a ajudar a les víctimes.

Inclusion body hepatitis (IBH) has been occurring as an economically important, emerging disease of broiler chickens in several countries. Historically, IBH has been identified as a secondary disease, often associated with common immunosuppressive diseases. However, few studies have identified IBH as a primary disease with no apparent association with immunosuppressive diseases. The objectives of this study were to develop an animal model of IBH in commercial broilers, to demonstrate vertical transmission of fowl adenoviruses (FAdVs) in broiler breeders and to control IBH in broilers by vaccinating their parents with an inactivated FAdV vaccine. In order to develop an animal model of IBH in commercial broilers, fourteen-day old broilers were inoculated intramuscularly with 1x104 1x107 CCID50 of either FAdV x11a-like virus, two strains of FAdV-8a (FAdV-8a strain TR-59 and FAdV-8a strain T8-A) or FAdV-11strain 1047. Four days following FAdV inoculation, 5% - 15% mortality was observed and dead birds showed histologic lesions of hemorrhagic necrotizing hepatitis. This animal model reproduced the clinical disease, and pathological lesions of IBH that have been described in commercial broilers. In order to demonstrate vertical transmission of the FAdV, 35-week-old broiler breeders were inoculated with 1x106 CCID50 of either FAdV x11a-like virus, FAdV-8a strain TR-59, FAdV-8a strain T8-A or FAdV-11 strain 1047. Eggs from infected breeders were collected and hatched seven days post-inoculation. Clinical signs or mortality were not observed in parents; however broiler progeny derived from broiler breeders inoculated with FAdV-8a strain T8-A had 30% IBH mortality by seven days of age. The hexon gene loop 1 sequence of the virus isolated from affected broiler progeny showed 100% identity to FAdV-8a strain T8-A. In order to demonstrate protection of broilers against IBH by vaccination of their parents, four groups of broiler breeders were vaccinated with either FAdV-8a strain T8-A (2x107 or 2x104 CCID50) formulated with 20% oil-in-water emulsion, or FAdV x11a-like virus (2x107 or 2x104 CCID50) formulated with 20% oil-in-water emulsion at the age of 12 and 15 weeks. The control group was inoculated with 20% oil-in-water emulsion. Broiler progeny were challenged with FAdV-8a strain T8-A to study the immunoprotective effect of the vaccine. Although, survival of broilers following FAdV-8a strain T8-A challenge was not significantly different among vaccinated and non-vaccinated groups (P>0.05), immunoprotective effect was enhanced by the increase dose of FAdV antigens (P>0.05). Further studies are necessary to improve the vaccine efficacy to protect broilers against IBH.<p> In conclusion, the results of this study support the hypothesis that IBH in broilers in Canada is a vertically-transmitted primary disease with no known immunosuppressive involvement. The results also demonstrated that inactivated antigens of FAdV are able to partially protect broilers against IBH by vaccinating their parents. Further studies with different formulations, and priming the immune system of broiler breeders with live FAdV prior to vaccination with inactivated FAdV vaccines are necessary to improve the efficacy of inactivated IBH vaccine.

This study tested the role of the calcium dependent cytosolic protein calpain in neutrophilic hepatitis. We hypothesized that inhibition of calpain would protect against LPS-induced neutrophilic liver damage. To test our hypothesis, a reliable LPS-mediated hepatitis model to investigate the mechanisms of hepatic neutrophil infiltration following LPS administration was developed by repeat intravenous injection of LPS at a dose of 10 mg/kg to rats. Blood was collected for hematologic and biochemical analysis and multiple organs including liver were collected for evaluation of histopathologic changes. Flow cytometry was employed to investigate L-selectin (CD 62L) and MAC-1 (CD11b/18) expression on neutrophils both in vivo and in vitro. Significant hematologic changes included neutrophilia, elevation in neutrophil to lymphocyte ratio with toxic changes and left shift. Biochemical changes were observed in several liver (AST, GGT) and kidney (BUN) parameters generally at the earliest time points. Histopathology revealed a time-dependent neutrophil and mononuclear infiltration around the periportal areas in the single dose study and mid-zonal inflammation with multifocal coagulative necrosis in the repeated dose study. CD 11b was up-regulated both in vitro and in vivo. After development of a suitable model, the first goal was to investigate the role of the intracellular enzyme calpain in the development of neutrophilic hepatitis and midzonal necrosis. A second goal was to compare the observed protective effects of calpain inhibition with a relatively selective inducible nitric oxide synthase (iNOS) inhibitor aminoguanidine and an inhibitor of coagulation, heparin. When compared to rats administered LPS alone, administration of calpain 1 inhibitor prior to LPS significantly reduced hepatic iNOS expression, hepatic neutrophil infiltration and attenuated midzonal hepatic necrosis. Administration of heparin and aminoguanidine prior to LPS also decreased liver iNOS expression, hepatic neutrophil infiltration and liver pathology comparable to calpain inhibition. Blood neutrophil activation, as measured by the neutrophil adhesion molecule CD11b integrin, was upregulated in all the LPS treated groups regardless of inhibitor administration. We conclude that amelioration of liver pathology via calpain inhibition is likely dependent on the down-regulation of iNOS expression in the rat model of LPS mediated hepatitis.