Hepatic fibrosis: physiopathology and biological diagnosis

Hepatic fibrosis, of which cirrhosis is the most advanced stage, can result from any chronic liver disease due to any cause. Normal extracellular matrix components accumulate in the liver as a result of imbalances in their production, deposition, and breakdown. These matrix components are produced primarily by myofibroblastic hepatic cells whose main cellular source in the liver is the stellate cell (Ito cell). Histopathological examination of a liver biopsy specimen is currently the gold-standard investigation for estimating the severity of fibrosis in patients with chronic liver disease. However, the recent development of treatments with activity against the fibrosing process requires evaluation of fibrosis at closely spaced intervals and, therefore, the development of tests that do not require a liver biopsy. Advances in our understanding of the mechanisms underlying hepatic fibrogenesis have allowed to identify several substances of potential clinical usefulness. Serum assays of extracellular matrix components, their breakdown products, or enzymes involved in their metabolism have been suggested for the noninvasive evaluation of hepatic fibrosis. Clinical studies have shown that serum hyaluronate is to date the marker with the closest correlations to hepatic fibrosis and the noninvasive parameter with the highest sensitivity for cirrhosis.     

结缔组织生长因子在慢性肝病诊断中的应用研究

探讨结缔组织生长因子(CTGF)在慢性肝病诊断中的应用价值。运用ELISA方法检测198例研究对象,观察血清CTGF水平的变化,分析CTGF水平与临床特征及实验室指标的相关性;运用实时荧光定量RT-PCR方法检测组织中CT-GF mRNA的表达量,比较各组间表达量的变化。乙肝后重度肝纤维化组、肝硬化组、原发性肝细胞癌(HCC)组的血清CTGF水平均显著高于正常对照组,且具有统计学意义(P<0.05);血清CTGF水平与部分临床实验室特征存在相关性,在区分早晚期肝纤维化上具有诊断提示作用;癌旁组织的CTGF mRNA相对表达量显著高于正常对照和癌组织的表达量且具有统计学差异(P<0.05)。血清CTGF水平与肝纤维化、肝硬化及肝癌的发生发展关系密切,有望成为一个新的无创性肝纤维化检测诊断指标,为临床诊断提供依据。     

Serum marker of type III procollagen in patients with idiopathic hemochromatosis and its relationship to hepatic fibrosis

A radioimmunoassay for serum procollagen III aminopeptide (sPIIIP) was proposed recently for monitoring hepatic fibroplasia in patients with various inflammatory hepatic lesions. To determine whether sPIIIP also can detect fibroplasia in noninflammatory liver disorders, we measured this index in 16 patients with idiopathic hemochromatosis (IHC) at various stages of the disease and iron overload. Interestingly, we found normal levels of sPIIIP in 12 out of 16 patients examined (75%), despite clear histologic features of fibrosis or cirrhosis. The levels of sPIIIP exhibited no relationship to any of the clinical, laboratory, or histologic parameters of the disease. Thus, unlike other types of cirrhosis, in which sPIIIP is increased, the liver disease in IHC may be a fibrotic process unrelated to type III collagen stimulation. Accordingly, the determination of sPIIIP in these patients is of no value for monitoring the fibrosis associated with the liver disease.     

Hepatitic inherited metabolic disorders

Primary metabolic disorders are a disparate group of diseases that may or may not be accompanied by hepatic manifestations. Those with liver involvement may show a range of histopathologic changes. Proper histologic diagnosis requires correlation with clinical and laboratory data, including evaluation for mutations either via serum protein electrophoresis or through formal genetic analysis. This article is a review of the three most common inherited metabolic disorders which may present with a hepatitic pattern. In alpha1-antitrypsin disorder, there is a broad range of clinical presentations, age at presentation, and histological features ranging from "neonatal hepatitis" to a chronic progressive hepatitis in later childhood and adulthood. Hence, this disorder must be in the differential diagnosis of liver disease of the very young, and in older children and adults, with or without coexistent overt pulmonary symptoms. In Wilson disease, presentation tends to be in older childhood or the adult, with a progressive chronic hepatitis. Cystic fibrosis may feature a characteristic obstructive biliary syndrome, coexisting with the many extrahepatic manifestations of this debilitating disease. Lastly, the progressive familial intrahepatic cholestasis (PFIC) syndromes are given as examples of inherited metabolic conditions in which relentlessly progressive cholestatic liver disease eventuates over years in end-stage cholestatic liver disease with cirrhosis. Distinguishing features include absence of elevated serum gamma-glutamyl transpeptidase (GGT) in PFIC-1 and PFIC-2, and elevated GGT in PFIC-3. However, molecular studies are required for a confident diagnosis of the rare PFIC syndromes.     

化学发光法检测肝纤维化血清学指标的临床应用

目的探讨化学发光法检测肝纤维化指标包括三型前胶原N端肽（PⅢNP）、Ⅳ型胶原（CⅣ）、层粘蛋白（LN）及透明质酸（HA）对肝纤维化的诊断价值。方法用化学发光法检测132例乙型病毒性肝炎患者血清中肝纤维化四项指标的水平,评价四项指标鉴别诊断肝炎及肝硬化的价值。结果乙型肝炎组、肝癌组、肝硬化组血清中的四项指标依次升高,均与正常对照组差异有统计学意义（P〈0.01）。ROC曲线显示,PⅢNP、CIV、LN、HA的曲线下面积分别为0.680、0.825、0.716、0.825,灵敏度分别为39.1%、87.0%、87.0%、82.6%,特异性分别为89.8%、69.3%、53.4%、86.4%,准确性分别为79.09%、72.73%、78.18%、85.45%。在联合检测中,HA＋PⅢNP组合的灵敏度为83.0%,特异性为80.0%,准确性为80.1%。结论单个指标检测,HA是四项指标中鉴别诊断肝炎与肝硬化最有价值的一项,通过HA联合其他指标进行分析,其中HA＋PⅢNP组合特异性、准确性最高。     

病毒性肝炎后肝硬化住院患者感染状况调查及危险因素分析

目的 调查病毒性肝炎后肝硬化住院患者的感染率和感染源,评估感染的危险因素.方法 采用横断面研究,连续收集382例病毒性肝炎后肝硬化住院患者,查阅患者相关临床资料,采用单因素分析、逻辑回归分析等方法分析患者感染相关因素和独立危险因素,微生物培养和鉴定分析感染源.结果 通过调查统计肝硬化住院患者感染率20.2％,77名患者感染,最常见感染是自发性细菌性腹膜炎（27例）,感染显著增加患者的死亡（22.1％vs.4.3％,P≤0.001）和延长住院时间（10 d vs.22 d,P≤0.001）.逻辑回归分析显示胃肠道出血和低白蛋白血症是肝硬化住院患者感染独立危险因素;共分离出66株菌,革兰阴性菌38株,革兰阳性菌26株,真菌2株.结论 感染增加病毒性肝炎后肝硬化住院患者死亡;胃肠道出血和低白蛋白血症是导致肝硬化住院患者感染独立危险因素.     

Diagnostic des hépatopathies et de leur sévérité

Diagnosis and prognosis of liver diseases are considered here in the context of surgery. When a chronic liver disease is suspected by clinical signs or abnormal liver function tests, the degree of liver fibrosis has to be evaluated. The most accurate markers to assess clinically significant fibrosis in clinical practice are now prothrombin index and serum hyaluronate. The diagnostic accuracy for cirrhosis approaches 90% using non invasive means. The most accurate signs are in clinics: firm liver, in laboratory tests: thrombopenia, decreased prothrombin index and increased hyaluronate, with ultrasonography-Doppler: increased portal diameter and decreased portal velocity and with endoscopy: esophageal varices (but this not a true non-invasive tool). Improvement by blood fibrosis markers and ultrasonography-Doppler are awaited. Child-Pugh score is the most used prognostic score in clinical practice and trials. This is due to its simplicity but some limitations are known. Therefore, other scores are used: APACHE III ou MELD in surgery or resuscitation, Maddrey's score in alcoholic hepatitis and Mayo Clinic's scores in cholestatic diseases.     

Subgroup analysis of the predictive ability of aspartate aminotransferase to platelet ratio index (APRI) and fibrosis-4 (FIB-4) for assessing hepatic fibrosis among patients with chronic hepatitis C

BackgroundThere are many laboratory indices to assess liver fibrosis. Aspartate aminotransferase to platelet ratio index (APRI) and fibrosis-4 (FIB-4) index have been used as well-known serum markers of liver fibrosis. With the increasing use of non-invasive fibrosis assessment, it is important to recognize the limitations of these tests. The factors influencing the diagnostic accuracy to evaluate liver fibrosis are not well-established. This study aimed to perform a subgroup analysis of the predictive ability of laboratory indices.MethodsOverall, 113 patients with chronic hepatitis C infection who underwent liver biopsy were retrospectively examined. The histological assessment of liver fibrosis was performed using the METAVIR scoring system, and the values of several laboratory tests were also evaluated on the same day. We categorized our study population by treatment status, body mass index (BMI), and age.ResultsThe two laboratory indices APRI and FIB-4 index could predict advanced (F3-4) liver fibrosis and cirrhosis (F4), with the area under the receiver operating characteristic curve (AUROC) > 0.8 and accuracy >70%. The AUROCs and accuracies were higher among patients with sustained virological response (SVR) than among those without SVR. A higher predictive ability was also observed among patients with BMI <25 kg/m². Age did not appear to affect liver fibrosis predictability.ConclusionsThe laboratory indices APRI and FIB-4 index exhibit good diagnostic performance for determining advanced fibrosis and cirrhosis among patients with hepatitis C infection. The diagnostic accuracy appears better among patients with SVR and those with BMI <25 kg/m².     

Comparison of non-invasive fibrosis markers and classical liver biopsy in chronic hepatitis C

The aim of this study was to compare the results of nine non-invasive serum biomarkers with liver biopsies to predict liver fibrosis stage. HCV-RNA-positive, HCV genotype 1, treatment-naive patients with chronic HCV infections were included from 14 centers (n=77). The platelet count, AST/ALT ratio (AAR), cirrhosis discriminate score (CDS), FIB4, AST/platelet ratio index (APRI), age-platelet (AP) index, G?teborg University cirrhosis index (GUCI), FibroTest, and ActiTest were calculated and compared to histologic findings. All serum biomarkers, except AAR, were weakly or moderately correlated with liver biopsy results (ISHAK fibrosis score). The mean scores of FibroTest, FIB4, APRI, and AP index were significantly different between F0-F2 and F3-F4 groups and the negative predictive values (NPVs) of the F3-F4 group were 95%, 85%, 85%, and 83%, respectively, for these serum biomarkers. Our study suggests that serum biomarkers may help to diagnose significant fibrosis but inadequate to detect fibrosis in early stages. Although liver biopsy is still the gold standard to diagnose liver fibrosis, FibroTest, FIB4, APRI, or AP index may be used to exclude significant fibrosis with >80% NPV.     

HFE-associated hereditary hemochromatosis

In populations of northern European descent, the p.C282Y mutation in the HFE gene is highly prevalent, and HFE-associated hereditary hemochromatosis is the most common type of inherited iron overload disorder. Inappropriate low secretion of hepcidin, which negatively regulates iron absorption, is postulated to be the mechanism for iron overload in this condition. The characteristic biochemical abnormalities are elevated serum transferrin-iron saturation and serum ferritin. Typical clinical manifestations include cirrhosis, liver fibrosis, hepatocellular carcinoma, elevated serum aminotransferase levels, diabetes mellitus, restrictive cardiomyopathy and arthropathy of the second and third metacarpophalangeal joints. Most patients are now diagnosed before the development of these clinical features. Molecular genetic tests are currently available for genotypic diagnosis. In selected individuals, diagnosis might require liver biopsy or quantitative phlebotomy. Iron depletion by phlebotomy is the mainstay of treatment and is highly effective in preventing the complications of iron overload if instituted before the development of cirrhosis. Genetic testing is currently not recommended for population screening because of low yield as the majority of the healthy, asymptomatic p.C282Y homozygotes do not develop clinically significant iron overload. HFE gene testing remains an excellent tool for the screening of first-degree relatives of affected probands who are p.C282Y homozygotes.     

乙型肝炎肝硬化患者乙型肝炎病毒DNA水平与肝纤维化程度的关系

目的 探讨乙型肝炎肝硬化患者乙型肝炎病毒(HBV)DNA水平与肝纤维化程度的关系及其临床意义.方法 回顾性分析2004年至2006年本科室收治的263例乙型肝炎肝硬化住院患者的临床资料.所有患者均进行肝功能Child-Pugh分级,检测HBV DNA、HBV血清标志物、透明质酸(HA)、人Ⅲ型前胶原(Hpc-Ⅲ)、Ⅳ型胶原(Ⅳ-C)、层粘蛋白(LN);行腹部超声检测脾大小、门静脉内径、脾静脉内径;胃镜检查食管静脉曲张程度,并记录常见并发症.根据HBV DNA水平分为4组:G1组,HBV DNA＜103拷贝/ml;G2组,HBV DNA 103～＜105拷贝/ml;G3组,HBV DNA 105～＜107拷贝/ml;G4组,HBV DNA≥107拷贝/ml.比较各组间Child-Pugh分级、肝纤维化血清指标和门脉高压指标的差异以及各组肝硬化常见并发症的发生情况.结果 263例患者中217例(82.5%)HBV DNA阳性.不同HBV DNA水平患者之间的Child-Pugh评分分级、HA、Hpc-Ⅲ、Ⅳ-C、LN比较,差异无统计学意义(均P＞0.05).4组患者之间脾大小、门静脉内径、脾静脉内径及食管静脉曲张程度比较,差异无统计学意义(均P＞0.05).4组患者并发症如消化道出血、继发感染、腹水、肝性脑病、肝癌等发生率差异也无统计学意义(均P＞0.05).结论 绝大部分乙型肝炎肝硬化患者HBV DNA阳性,但血清HBV DNA水平高低与肝硬化严重程度及并发症的发生率无明显关联.     

骨髓间充质干细胞移植治疗肝硬化的研究进展

肝硬化是临床中常见的慢性进行性肝病,目前治疗晚期肝硬化最有效的方法是肝脏移植,但肝源缺乏、费用昂贵、移植排斥反应及长期应用免疫抑制剂引起并发症等成为限制其广泛应用的主要原因.干细胞移植有利于受损肝组织修复,能够代偿部分肝功能,已成为治疗肝病的一种新方法.就骨髓间充质干细胞移植治疗肝硬化的基础、临床研究进展、存在的问题以及发展前景作一综述,旨在为其进一步研究提供理论依据.     

Similar increased serum dipeptidyl peptidase IV activity in chronic hepatitis C and other viral infections.

BACKGROUND: Dipeptidyl peptidase IV is a transmembrane enzyme widely expressed in many cell types, but also present as a soluble form in biological fluids. Its abnormal activity is sometimes associated with liver disease related pathologies. OBJECTIVES: The aim of this study was to evaluate the clinical relevance of changes in serum DPPIV activity in hepatitis C and other viral infections. STUDY DESIGN: DPPIV activity was assessed by using a microplate-based colorimetric assay on serum from 88 subjects: 12 healthy uninfected controls, 10 patients with primary biliary cirrhosis (PBC) as a reference group, 36 HCV-infected patients, and patients suffering from viral infections of different etiologies. Levels of DPPIV activity were compared with: (1) those of other serum biochemical parameters such as alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma glutamyl transpeptidase (GGT), and bilirubin concentrations; and (2) criteria representative of liver histological status. RESULTS: Compared with healthy subjects, DPPIV activity was significantly increased during viral infections and in PBC (P<0.01). In HCV-infected patients, the median activity (interquartile range, IQR), 29.78 IU/l (24.66-35.95), differed significantly (P<0.05) from that of controls: 21.42 (19.76-24.93). No correlation was observed between DPPIV activity and either ALT, AST, bilirubin, or the stage of liver fibrosis and necroinflammatory activity, although GGT was moderately correlated (r=0.58, P<0.05). CONCLUSIONS: Although we confirmed an elevation of serum DPPIV activity in PBC, it seems to be a non-specific phenomenon common to viral infections. The absence of correlation between serum DPPIV and markers of liver disease in HCV-infected patients, suggests that this activity originates not only from the liver, but also from other sources such as peripheral blood cells involved in the control of viral infections.     

PULMONARY HYPERTENSION IN HEPATITIS B VIRUS CARRIERS

Two autopsy cases of pulmonary hypertension (PH) associated with liver cirrhosis are presented. Both patients were hepatitis B (HB) virus carriers and suffered from type B cirrhosis during the clinical course. The first patient was a 52-y-ear-old male with type B cirrhosis. He died of hepatic encephalopathy but did not have any specific symptoms for PH except abnormal laboratory findings. Chest roentgenograms displayed prominence of the central pulmonary artery. Cardiac catheterization indicated marked increment of pulmonary arterial pressure. Autopsy revealed dilatation and sclerosis of the main pulmonary artery and right ventricular hypertrophy. Microscopically, the pulmonary arteries showed intimal fibrosis, medial hypertrophy, and plexiform lesions throughout the lungs. The second patient, a 15-y-ear-old boy, had PH with juvenile liver cirrhosis which had existed for 8 years prior to the onset of PH. He complained of severe dyspnea and dizziness before death. Electrocardiogram indicated right ventricular hypertrophy. Autopsy disclosed cardiomegaly, type B cirrhosis and sclerotic pulmonary arteries. Grade VI pulmonary plexogenic arteriopathy including plexiform lesions and necrotizing arteritis was observed. HBsAg was detected in both the hepatocytes and the pulmonary arterial walls. We discuss the possible relationship between persistent HB viral infection and PH with liver cirrhosis.     

Hyaluronic acid concentration in liver diseases

The aim of this study was to evaluate the effect of liver diseases of different etiologies and clinical severity of liver cirrhosis on the serum level of hyaluronic acid. The results were compared with noninvasive markers of liver fibrosis: APRI, GAPRI, HAPRI, FIB-4 and Forn’s index. Serum samples were obtained from 20 healthy volunteers and patients suffering from alcoholic cirrhosis (AC)—57 patients, non-alcoholic cirrhosis (NAC)—30 and toxic hepatitis (HT)—22. Cirrhotic patients were classified according to Child–Pugh score. Hyaluronic acid concentration was measured by the immunochemical method. Non-patented indicators were calculated using special formulas. The mean serum hyaluronic acid concentration was significantly higher in AC, NAC and HT group in comparison with the control group. There were significant differences in the serum hyaluronic acid levels between liver diseases, and in AC they were significantly higher than those in NAC and HT group. The serum hyaluronic acid level differs significantly due to the severity of cirrhosis and was the highest in Child–Pugh class C. The sensitivity, specificity, accuracy, positive and negative predictive values and the area under the ROC curve for hyaluronic acid and all non-patented algorithms were high and similar to each other. We conclude that the concentration of hyaluronic acid changes in liver diseases and is affected by the severity of liver cirrhosis. Serum hyaluronic acid should be considered as a good marker for noninvasive diagnosis of liver damage, but the combination of markers is more useful.     

Pulmonary hypertension in hepatitis B virus carriers

Two autopsy cases of pulmonary hypertension (PH) associated with liver cirrhosis are presented. Both patients were hepatitis B (HB) virus carriers and suffered from type B cirrhosis during the clinical course. The first patient was a 52-year-old male with type B cirrhosis. He died of hepatic encephalopathy but did not have any specific symptoms for PH except abnormal laboratory findings. Chest roentgenograms displayed prominence of the central pulmonary artery. Cardiac catheterization indicated marked increment of pulmonary arterial pressure. Autopsy revealed dilatation and sclerosis of the main pulmonary artery and right ventricular hypertrophy. Microscopically, the pulmonary arteries showed intimal fibrosis, medial hypertrophy, and plexiform lesions throughout the lungs. The second patient, a 15-year-old boy, had PH with juvenile liver cirrhosis which had existed for 8 years prior to the onset of PH. He complained of severe dyspnea and dizziness before death. Electrocardiogram indicated right ventricular hypertrophy. Autopsy disclosed cardiomegaly, type B cirrhosis and sclerotic pulmonary arteries. Grade VI pulmonary plexogenic arteriopathy including plexiform lesions and necrotizing arteritis was observed. HBsAg was detected in both the hepatocytes and the pulmonary arterial walls. We discuss the possible relationship between persistent HB viral infection and PH with liver cirrhosis.     

慢性病毒性肝炎纤维化分期与血清学指标的关系

OBJECTIVE: To assess the correlation between serological fibrosis markers and staging of fibrosis in chronic hepatitis. METHODS: One hundred and fourteen (114) biopsy and 13 autopay liver specimen were reviewed pathohistologically. Serum samples for liver function tests and fibrosis marker assays including serum P-III-P, IV collagen, laminin (LN), hyaluronic acid (HA), h-TIMP-1 were collected simultaneously right before the biopsy or autopsy. HE, sirius red stains as well as staining for reticulum and elastic fiber were done. In besides, IV collagen, laminin, activated stellate cell were assayed by immunohistochemical methods. RESULTS: Among 127 patients, 92 cases of chronic viral hepatitis including early cirrhosis and 18 cases of hepatic cirrhosis were examined pathologically (17 alcoholic liver disease excluded). The overall inflammatory index and fibrotic scoring were noticed to be significantly correlated with each other (r = 0.82, p < 0.01); The markers, such as HA, P-III-P, LN, IV collagen, h-TIMP-1 were positively correlated with the fibrotic staging and scoring (r = 0.610, 0.575, 0.607, 0.641, 0.606 respectively). The higher the marker level, the more serious the fibrotic change. In addition, (18 cases) patients with active cirrhosis (16 cases) showed higher serum marker level than that of the early cirrhosis and the serum markers in the later were higher than that in the non-active cirrhosis. CONCLUSION: Serum fibrosis markers are fairly well correlated with the staging of fibrosis and are considered to be the valuable references for clinical diagnosis. The close correlation between inflammation process and fibrosis suggests that the inflammatory process plays an important role in fibrogenesis.     

Serum hyaluronan: a marker of liver fibrosis in patients with chronic liver disease

The aim of this study was to evaluate the clinical significance of serum hyaluronan (HA) as a marker of liver fibrosis in patients with chronic liver disease. Serum HA was measured by an ELISA-based method in 28 patients with chronic hepatitis (CH), 43 patients with liver cirrhosis (LC), 57 patients with hepatocellular carcinoma (HCC) and 60 healthy controls. Mean serum HA concentration in patients with LC was 1,376.80 +/- 2,568.85 ng/ml which was significantly higher than those in patients with CH, HCC and the controls (575.93 +/- 732.58, and 426.36 +/- 687.33, and 117.86 +/- 311.11 ng/ml, respectively). Based on a ROC curve analysis, a cut-off point of 354 ng/ml discriminated between LC and other groups with a sensitivity, specificity and accuracy of 82.4%, 78.2%, and 80.2%, respectively. Mean HA concentrations were correlated with the degree of liver fibrosis, but not the grade of necroinflammatory activity. In patients with LC, the mean serum HA level was significantly increased in the Child C group (3,977.96 +/- 4,906.21 ng/ml) in comparison with the Child B and A groups (1,002.63 +/- 448.55, and 537.90 +/- 424.16 ng/ml, respectively). We conclude that serum HA concentrations reflect the extent of liver fibrosis and severity of cirrhosis. Thus, serum HA can be a diagnostic marker of liver fibrosis and cirrhosis in patients with chronic liver disease.     

Prediction of fibrosis progression in chronic viral hepatitis

Prediction of liver fibrosis progression has a key role in the management of chronic viral hepatitis, as it will be translated into the future risk of cirrhosis and its various complications including hepatocellular carcinoma. Both hepatitis B and C viruses mainly lead to fibrogenesis induced by chronic inflammation and a continuous wound healing response. At the same time direct and indirect profibrogenic responses are also elicited by the viral infection. There are a handful of well-established risk factors for fibrosis progression including older age, male gender, alcohol use, high viral load and co-infection with other viruses. Metabolic syndrome is an evolving risk factor of fibrosis progression. The new notion of regression of advanced fibrosis or even cirrhosis is now strongly supported various clinical studies. Even liver biopsy retains its important role in the assessment of fibrosis progression, various non-invasive assessments have been adopted widely because of their non-invasiveness, which facilitates serial applications in large cohorts of subjects. Transient elastography is one of the most validated tools which has both diagnostic and prognostic role. As there is no single perfect test for liver fibrosis assessment, algorithms combining the most validated noninvasive methods should be considered as initial screening tools.