Diffuse liver disease is a growing problem and a major cause of death worldwide. In the final stages the treatment often involves liver resection or transplant and in deciding what course of action is to be taken it is crucial to have a correct assessment of the function of the liver. The current “gold standard” for this assessment is to take a liver biopsy which has a number of disadvantages. As an alternative, a method involving magnetic resonance imaging and mechanistic modeling of the liver has been developed at Linköping University. One of the obstacles for this method to overcome in order to reach clinical implementation is the speed of the parameter estimation. In this project the methodology of metamodeling is tested as a possible solution to this speed problem. Metamodeling involve making models of models using extensive model simulations and mathematical tools. With the use of regression methods, clustering algorithms, and optimization, different methods for parameter estimation have been evaluated. The results show that several, but not all, of the parameters could be accurately estimated using metamodeling and that metamodeling could be a highly useful tool when modeling biological systems. With further development, metamodeling could bring this non-invasive method for estimation of liver function a major step closer to application in the clinic.

Introduction: Non-invasive assessment of steatosis and fibrosis is of growing relevance in non-alcoholic fatty liver disease (NAFLD). 1H-Magnetic resonance spectroscopy (1H-MRS) and the ultrasound-based controlled attenuation parameter (CAP) correlate with biopsy proven steatosis, but have not been correlated with each other so far. We therefore performed a headto- head comparison between both methods. Methods: Fifty patients with biopsy-proven NAFLD and 15 healthy volunteers were evaluated with 1H-MRS and transient elastography (TE) including CAP. Steatosis was defined according to the percentage of affected hepatocytes: S1 5-33%, S2 34–66%, S3 $67%. Results: Steatosis grade in patients with NAFLD was S1 36%, S2 40% and S3 24%. CAP and 1H-MRS significantly correlated with histopathology and showed comparable accuracy for the detection of hepatic steatosis: areas under the receiveroperating characteristics curves were 0.93 vs. 0.88 for steatosis $S1 and 0.94 vs. 0.88 for $S2, respectively. Boot-strapping analysis revealed a CAP cut-off of 300 dB/m for detection of S2-3 steatosis, while retaining the lower cut-off of 215 dB/m for the definition of healthy individuals. Direct comparison between CAP and 1H-MRS revealed only modest correlation (total cohort: r = 0.63 [0.44, 0.76]; NAFLD cases: r = 0.56 [0.32, 0.74]). For detection of F2–4 fibrosis TE had sensitivity and specificity of 100% and 98.1% at a cut-off value of 8.85 kPa. Conclusion: Our data suggest a comparable diagnostic value of CAP and 1H-MRS for hepatic steatosis quantification. Combined with the simultaneous TE fibrosis assessment, CAP represents an efficient method for non-invasive characterization of NAFLD. Limited correlation between CAP and 1H-MRS may be explained by different technical aspects, anthropometry, and presence of advanced liver fibrosis.

This thesis investigates the epidemiology of hepatitis B virus infection (HBV) and estimates HBV-related liver disease burden in Vietnam and Australia using a cross-sectional study design and mathematical modelling. A population-based seroprevalence survey was undertaken in rural Northern Vietnam. In a sample of 870 study participants, prevalence of anti-HBV core antibody (anti-HBc) and hepatitis B virus surface antigen (HBsAg) was 68.2% and 19.0%, respectively, and hepatitis B e antigen (HBeAg) was detected in 16.4% of the HBsAg-positive group. Factors associated with HBV infection (anti-HBc and/or HBsAg-positive) were age 60 years or older (adjusted odds ratio (AOR), 3.82; 95% CI, 1.35??10.80; P = 0.01), residence in Vu Thu district (AOR, 3.00; 95% CI, 2.16??4.17; P <0.001), hospital admission (AOR, 2.34; 95% CI, 1.33??4.13; P = 0.003) and history of acupuncture (AOR, 2.01; 95% CI, 1.29??3.13; P = 0.002). Household contact with a person with liver disease (AOR, 2.13; 95% CI, 1.29??3.52; P = 0.003), reuse of syringes (AOR, 1.81; 95% CI, 1.25??2.62; P = 0.002) and sharing of razors (AOR, 1.69; 95% CI, 1.03??2.79; P = 0.04) were independent predictors of HBsAg positivity. Alanine aminotransferase (ALT) level was elevated (>40 IU/L) in 43% of the HBsAg-positive group; the proportion of elevated ALT was higher in HBeAg-positive (65%) compared with HBeAg-negative (39%) (P = 0.02). Based on data from the seroprevalence study, other prevalence estimates and HBV natural history parameters, a mathematical model was used to estimate HBV-related liver disease burden in Vietnam. Estimated chronic HBV prevalence increased from 6.4 million cases in 1990 to around 8.4 million cases in 2005 and was projected to decrease to 8.0 million by 2025. Estimated HBV-related liver cirrhosis and hepatocellular carcinoma (HCC) incidence increased linearly from 21 900 and 9400 in 1990 to 58 650 and 25 000 in 2025. Estimated HBV-related mortality increased from 12 600 in 1990 to 40 000 in 2025. To estimate HBV-related HCC incidence among Australians born in the Asia-Pacific region (APR), a mathematical modelling was developed utilising HBV natural history parameters, HBV prevalence estimates in APR countries and immigration data. Chronic HBV cases among the APR-born population increased rapidly from the late 1970s, reaching a peak of 4182 in 1990. Chronic HBV prevalence increased to more than 53 000 in 2005. Estimates of HBV-related HCC increased linearly from one in 1960 to 140 in 2005, with a projected increase to 250 in 2025. Universal HBV vaccination programs in countries of origin had limited impact on projected HBV-related HCC to 2025. HBV-related HCC survival was analysed in a population-based linkage study in New South Wales (NSW), Australia. Between 1994 and 2002, 278 HCC cases notified to the NSW Cancer Registry were linked to chronic HBV infection notifications to the NSW Health Department. The majority of cases were male (83.5%) and overseas born (93.6%); Asian-born cases accounted for 72.1%. Median survival following HCC diagnosis was 15 months. HCC survival was poorer among older age groups (P <0.001), and among cases with regional spread (HR 3.23; 95% CI, 1.83??5.69; P <0.001) and distant metastases (HR 3.85; 95% CI, 2.44??6.08; P <0.001). Sex, region of birth, and study period (1994??1997 versus 1998??2002) were not associated with HCC survival. The results of these studies show that HBV infection remains a major public health challenge in highly endemic countries such as Vietnam. HBV-related liver disease burden in Vietnam was estimated to increase for at least two decades despite the introduction of a universal infant HBV-vaccination program. Similarly, HBV-related HCC among Australians born in the APR was estimated to continue to increase over the next two decades. Survival for HBV-related HCC even in settings such as Australia continues to be extremely poor. Strategies are required to expand HBV treatment to individuals with chronic HBV infection who are at greatest risk of progression to advanced liver disease.

Increasingly chronic liver disease is being acknowledged as a complication of type 2 diabetes, in particular non-alcoholic fatty liver and non-alcoholic fatty liver disease. Rates of non-alcoholic fatty liver are higher in people with type 2 diabetes than in the general population, with prevalence rates believed to be between 40-70%. Given the aging Scottish population and the obesity driven diabetes epidemic, the problem of chronic liver disease is likely to increase. Despite this there has been little investigation into the natural history of nonalcoholic fatty liver disease and the risks of clinically significant chronic liver disease in community based cohorts because diagnosis has been heavily reliant on liver biopsy. The use of liver biopsy is limited in both research and clinical practice due to its associated high mortality (1/1000) and morbidity and also due to practical limitations (sampling variability, semi-quantitative scoring systems). As a result the use of non-invasive markers of liver injury (non-specific liver injury, steatosis, steatohepatitis, liver fibrosis and surrogates of advanced portal hypertension) are rising, in the diagnosis of chronic liver disease, however, their utility in both community cohorts and patients with type 2 diabetes has not been widely studied. The aims of the studies presented in the thesis, using the Edinburgh Type 2 Diabetes Study, were: (i) to describe the distributions of a range of non-invasive markers of steatohepatitis and liver fibrosis in older people with type 2 diabetes, their relationship with metabolic and liver disease risk factors, and to compare the agreement of different non-invasive markers of hepatic fibrosis; (ii) to determine the frequency (prevalence and incidence) of and risk factors for clinically significant chronic liver disease in people with type 2 diabetes; and (iii) to determine the importance of chronic liver disease as a risk factor (or risk marker) for cardiovascular mortality or morbidity in type 2 diabetes. Prior to undertaking this work I undertook a detailed systematic review of the literature relating to the use of non-invasive markers of hepatic fibrosis to inform the choice of markers used in the study. Examination of a wide range of potential markers of steatohepatitis and liver fibrosis found varied relationships with diabetes history. Most commonly, elevated markers of steatohepatitis and liver fibrosis were associated with older age and higher body fat measures. However, most of these relationships between liver markers and body fat measures lost statistical significance when limiting the population to only those with hepatic steatosis and/or non-alcoholic fatty liver disease. There were marked differences in the associations between different liver fibrosis markers and potential diabetes and metabolic risk factors, suggesting that these markers are not actually measuring the same underlying “fibrosis” condition. There was poor correlation between the five markers of liver fibrosis studied. Using the top vigintile (5%) of each marker resulted in excellent agreement on the absence of advanced liver disease but poor agreement on the presence of advanced liver disease. The prevalence of clinically significant CLD (defined as cirrhosis, HCC or gastrooesophageal varices) was 2.2% - 0.9% diagnosed prior to enrolment with an additional 1.4% identified by study investigations. Over nearly 6 years of follow-up, only 1.4% of the cohort developed incident clinically significant CLD. Higher levels of systemic inflammation, steatohepatitis and hepatic fibrosis markers were associated with both unknown prevalent and incident clinically significant chronic liver disease. Less than half of participants developing incident significant disease were identified as high risk by the study investigations. Abnormal liver enzymes were statistically significantly associated with incident cases, however the presence of hepatic steatosis was not. There were 372/1033 (36.0%) patients with prevalent CVD and 319 (30.9%) with prevalent CAD at baseline. After mean follow-up of 4.4 years there were 44/663 incident CVD events, including 27 CAD events. There were 30/82 CVD related deaths. However, risk of dying from or developing CVD was no higher in subjects with steatosis than in those without. There was also no statistically significant relationship between CVD and steatohepatitis or liver fibrosis. The only statistically significant relationship between CVD and any liver markers was with GGT (prevalent CVD, OR 1.28, p=0.007; incident CAD, OR 2.35, p=0.042), suggesting that in our study population, CLD may have little effect on the development of, or mortality from, CVD. In conclusion, the potential for using non-invasive biomarkers to diagnose clinically significant chronic liver disease in type 2 diabetes remains limited, however chronic liver disease is a significant problem in older people with type 2 diabetes and is frequently undiagnosed.

Made available in DSpace on 2014-06-11T19:23:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2004Bitstream added on 2014-06-13T18:20:03Z : No. of bitstreams: 1 mendonca_aj_me_botfmvz.pdf: 219760 bytes, checksum: 43a74ac93b405394f14e341212bc66fa (MD5) / Universidade Estadual Paulista (UNESP) / A Clínica Médica Veterinária de pequenos animais tem avançado muito no diagnóstico da doença hepática. Sabemos que diversos testes laboratoriais usados rotineiramente na clínica são sensíveis indicadores de doença hepática em cães, no entanto, outros exames igualmente valiosos raramente são solicitados, como os testes de avaliação da hemostasia. A proposta deste estudo foi avaliar os perfis hemostático, hematológico e bioquímico de cães com doenças hepáticas. Foram utilizados 44 animais divididos em dois grupos. Vinte cães com evidência histórica e/ou clínica de doença hepática, provenientes do Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Unesp/ Campus de Botucatu, foram selecionados com base no aumento da atividade sérica da enzima alanina amino transferase (ALT) > 50 UI/L. O grupo controle foi constituído por 24 cães hígidos, adultos, provenientes de proprietários particulares. Todos os animais foram submetidos aos mesmos exames laboratoriais: hemograma, contagem de plaquetas, tempo de coagulação, tempo de tromboplastina parcial ativada (TTPA), tempo de protrombina (TP), atividade enzimática das enzimas ALT e fosfatase alcalina (FA), dosagens das proteínas plasmáticas totais (PPT), proteínas totais séricas (PT), albumina e globulina séricas e fibrinogênio. Os resultados obtidos foram comparados pelo teste t de Student e pelo teste não paramétrico de Mann Withney. Concluiu-se que nas doenças hepáticas de cães há alteração do perfil hemostático, hematológico e bioquímico refletido por trombocitopenia, aumento dos tempos de coagulação, de protrombina e tempo de tromboplastina parcial ativada, anemia hipocrômica, neutrofilia sem desvio à esquerda, linfopenia, hipoalbuminemia e aumento da atividade sérica das enzimas FA e ALT. / The small animal practice has been advancing in liver diseases diagnosis. Several laboratory assays are sensible liver diseases indicators in dogs, however, other valuable assays as the hemostasis evaluation tests are seldom requested. The purpose of this study was to evaluate the hemostatic, hematological and chemistry profiles in dogs with liver diseases. Forty four animals divided in two groups were used. Twenty dogs with historical and/or clinical evidence of liver disease, from the Veterinary Hospital of Faculdade de Medicina Veterinária e Zootecnia da Unesp/ Campus de Botucatu were selected on the basis of increased serum alanine aminotransferase activity (ALT) > 50 UI/L. The control group was formed by 24 adult healthy dogs, from particular owners. All animals were submitted to the same laboratory tests: count blood cells (CBC), platelet count, coagulation time, prothrombin time (PT), activated partial thromboplastin time (APTT), serum ALT and alkaline phosphatase (ALP) activities, total plasma protein, total serum protein, albumin, globulin and fibrinogen determinations. The results were compared with Student t-test and Mann-Whitney rank sum test. It was concluded that liver diseases in dogs lead to changes in the hemostatic, hematological and chemistry profile, characterized by thrombocitopenia, prolonging of coagulation time, PT and APTT, hipochromic anemia, neutrophilia without left shift, limphopenia, hipoalbuminemia and increased ALP and ALT serum activities.

Orientador: Regina Kiomi Takahira / Resumo: A Clínica Médica Veterinária de pequenos animais tem avançado muito no diagnóstico da doença hepática. Sabemos que diversos testes laboratoriais usados rotineiramente na clínica são sensíveis indicadores de doença hepática em cães, no entanto, outros exames igualmente valiosos raramente são solicitados, como os testes de avaliação da hemostasia. A proposta deste estudo foi avaliar os perfis hemostático, hematológico e bioquímico de cães com doenças hepáticas. Foram utilizados 44 animais divididos em dois grupos. Vinte cães com evidência histórica e/ou clínica de doença hepática, provenientes do Hospital Veterinário da Faculdade de Medicina Veterinária e Zootecnia da Unesp/ Campus de Botucatu, foram selecionados com base no aumento da atividade sérica da enzima alanina amino transferase (ALT) > 50 UI/L. O grupo controle foi constituído por 24 cães hígidos, adultos, provenientes de proprietários particulares. Todos os animais foram submetidos aos mesmos exames laboratoriais: hemograma, contagem de plaquetas, tempo de coagulação, tempo de tromboplastina parcial ativada (TTPA), tempo de protrombina (TP), atividade enzimática das enzimas ALT e fosfatase alcalina (FA), dosagens das proteínas plasmáticas totais (PPT), proteínas totais séricas (PT), albumina e globulina séricas e fibrinogênio. Os resultados obtidos foram comparados pelo teste t de Student e pelo teste não paramétrico de Mann Withney. Concluiu-se que nas doenças hepáticas de cães há alteração do perfil hemostático, hematológico e bioquímico refletido por trombocitopenia, aumento dos tempos de coagulação, de protrombina e tempo de tromboplastina parcial ativada, anemia hipocrômica, neutrofilia sem desvio à esquerda, linfopenia, hipoalbuminemia e aumento da atividade sérica das enzimas FA e ALT. / Abstract: The small animal practice has been advancing in liver diseases diagnosis. Several laboratory assays are sensible liver diseases indicators in dogs, however, other valuable assays as the hemostasis evaluation tests are seldom requested. The purpose of this study was to evaluate the hemostatic, hematological and chemistry profiles in dogs with liver diseases. Forty four animals divided in two groups were used. Twenty dogs with historical and/or clinical evidence of liver disease, from the Veterinary Hospital of Faculdade de Medicina Veterinária e Zootecnia da Unesp/ Campus de Botucatu were selected on the basis of increased serum alanine aminotransferase activity (ALT) > 50 UI/L. The control group was formed by 24 adult healthy dogs, from particular owners. All animals were submitted to the same laboratory tests: count blood cells (CBC), platelet count, coagulation time, prothrombin time (PT), activated partial thromboplastin time (APTT), serum ALT and alkaline phosphatase (ALP) activities, total plasma protein, total serum protein, albumin, globulin and fibrinogen determinations. The results were compared with Student t-test and Mann-Whitney rank sum test. It was concluded that liver diseases in dogs lead to changes in the hemostatic, hematological and chemistry profile, characterized by thrombocitopenia, prolonging of coagulation time, PT and APTT, hipochromic anemia, neutrophilia without left shift, limphopenia, hipoalbuminemia and increased ALP and ALT serum activities. / Mestre

A dosagem de gama-glutamil transpeptidase sérica (GGT) tem sido amplamente utilizada como marcador bioquímico do uso de álcool. Sua utilização no rastreamento do consumo de álcool em pacientes com doença hepática diagnosticada necessita ser melhor investigada. Neste estudo foram comparados os níveis séricos de GGT ao padrão de consumo de álcool avaliado por meio do teste de rastreamento AUDIT em 126 indivíduos hepatopatas (94 homens e 32 mulheres), com idade entre 20 a 69 anos. Vinte e dois indivíduos (17,4%) obtiveram pontuação maior ou igual a 8 no AUDIT (casos positivos para suspeição de problemas relacionados ao consumo de álcool nos últimos 12 meses). Este percentual eleva-se a 32,7% nos pacientes com diagnóstico de hepatopatia associada ao uso do álcool. A gravidade da hepatopatia foi avaliada com base na classificação de Child-Pugh: 86 pacientes foram classificados como A (68,2%) e 40 como B ou C (31,8%). Todos os pacientes com pontuação &#8805;8 no AUDIT foram do sexo masculino e 77,3% deles tiveram diagnóstico de doença hepática associada ao uso de álcool (p<0,0001). Pacientes com pontuação &#8805;8 no AUDIT apresentaram valores médios de GGT significantemente maiores quando comparados àqueles menores que 8 (526,9 U/L ± 1006,8 versus 138,7 U/L ± 123, p<0,00001). O teste de correlação de Pearson indicou uma forte associação entre a elevação dos valores de GGT em pacientes hepatopatas que fazem uso de álcool e a pontuação total no AUDIT. Pacientes hepatopatas, apesar de manifestarem valores elevados de GGT, as diferenças não estiveram relacionadas à gravidade da hepatopatia. Não houve diferença estatisticamente significante em relação à pontuação &#8805;8 no AUDIT e idade, estado civil, situação de emprego, escolaridade, renda familiar, cor e religião. Nossos dados sugerem que a utilização combinada do GGT e do AUDIT pode ser útil em discriminar pacientes hepatopatas usuários de álcool, principalmente em países em desenvolvimento como o Brasil, devido ampla disponibilidade e baixo custo. / The gamma glutamyltranspeptidase (GGT) has been widely employed as excessive alcohol use biochemical marker. Its utilization in screening of alcohol consumption in patients with diagnosed liver diseases must be better investigated. In this study, serum levels of GGT were compared to the pattern of alcohol consumption using the AUDIT test as alcohol screening instrument in 126 patients with liver disease (94 men and 32 women), with age ranged from 20 to 69 years old. Twenty two patients (17,4%) scored higher or equal 8 in the AUDIT (positive cases for alcohol related problems suspicion in the last 12 months). This proportion increases to 32,7% in patients with alcohol-associated liver disease. The severity of the liver damage was evaluated by the Child-Pugh classification: 86 patients were classified as A (68,2%) and 40 as B or C (31,8%). All patients who scored 8 or higher in the AUDIT were men and had mean values of GGT significantly higher when compared to those who scored less than 8 (526,9 U/L ± 1006,8 versus 138,7 U/L ± 123, p<0,00001). Among them 77,3% had alcohol-associated liver disease diagnosis (p<0,0001). The Pearson’s correlation test showed a strong association between increase of the GGT values in patients that use alcohol and total score in the AUDIT. No association between increase of GGT values and severity of liver damage was found. No statistically significance was observed also between AUDIT scores 8 or higher to age, civil status, employment situation, education, familiar earnings, race or religion. Our data suggest that the combined use of GGT and AUDIT can be useful in discriminating liver disease patients that use alcohol, particularly in developing countries like Brazil, due to their widely availability and low costs.

Nonalcoholic fatty liver disease (NAFLD) is categorized into nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) and has emerged as a risk factor for more critical clinical conditions. However, the underlying mechanisms of NAFLD pathogenesis are not fully understood. In this study, expression of proteins associated with endoplasmic reticulum (ER) stress, apoptosis and autophagy were analyzed in normal, NAFL and NASH human livers by western blotting. Levels of some ER stress-transducing transcription factors, including cleaved activating transcription factor 6, were higher in NASH than in the normal tissues. However, the expression of a majority of the ER chaperones and foldases analyzed, including glucose-regulated protein 78 and ER protein 44, was lower in NASH than in the normal tissues. Levels of apoptosis markers, such as cleaved poly (ADP-ribose) polymerase, were also lower in NASH tissues, in which expression of some B-cell lymphoma-2 family proteins was up-or down-regulated compared to the normal tissues. The level of the autophagy substrate p62 was not different in NASH and normal tissues, although some autophagy regulators were up-or down-regulated in the NASH tissues compared to the normal tissues. Levels of most of the proteins analyzed in NAFL tissues were either similar to those in one of the other two types, NASH and normal, or were somewhere in between. Together, these findings suggest that regulation of certain important tissues processes involved in protein quality control and cell survival were broadly compromised in the NAFLD tissues.

No description available.

The detection or exclusion of metastatic liver involvement is critical in the management and prognosis of patients with malignant disease. Noninvasive imaging modalities such as computed tomography, ultrasound, and technetium colloid liver scan are highly sensitive but nonspecific. Serum alkaline phosphatase is of similar value. A blind liver biopsy by the Menghini technique is often done to confirm the diagnosis, but its yield is low. We prospectively evaluated 74 patients using blind Menghini needle biopsy and concurrent Chiba fine-needle aspiration biopsy (FNAB) techniques. A positive diagnosis of malignancy was made in 30 patients (41%). In only 25 (34%) was the diagnosis made by Menghini biopsy, while Chiba FNAB confirmed the diagnosis in all 30 patients. Thus, concurrent use of both needles increased the diagnostic accuracy by 7%. Seven additional patients, considered to have one or more contraindications for the Menghini biopsy, underwent Chiba FNAB alone; the diagnosis was confirmed in all without complication. We conclude that FNAB alone or in combination with Menghini biopsy is valuable and safe in the diagnosis of metastatic liver disease.