Non-invasive tests for liver fibrosis: encouraging or discouraging results?

Evaluation of liver fibrosis with a monoexponential model of intravoxel incoherent motion magnetic resonance imaging

To evaluate hepatic fibrosis with a monoexponential model of intravoxel incoherent motion magnetic resonance imaging, and assess the potential application value of intravoxel incoherent motion (IVIM) in diffusion-weighted imaging (IVIM-DWI) in determining staging of liver fibrosis. 28 patients with hepatic fibrosis and 25 volunteers with healthy livers had IVIM examination and conventional MRI. All standard apparent diffusion coefficient (ADC) values of IVIM raw data were post-processed off-line after completion of data collection. All regions of interest (ROIs) were manually positioned by two experienced radiologists. All values of the different fibrosis stages in the study group were compared using independent sample t tests. Using ROC analysis, both AUC values of ADC_total and ADC_{0-400-600-800} from study and control group were found to be between 0.8 and 1 for staging fibrosis. The mean ADC_total and ADC_{0-400-600-800} values of the liver in the study group were significantly lower than the values in the control group (P < 0.05). Spearman rho correlation analysis was used to determine the relationship among fibrosis stages and the ADC_total and ADC_{0-400-600-800} in the study group. As the stage of the fibrosis increased, the values decreased. Significant differences between the two subgroups of liver fibrosis stages were found (P < 0.05). The monoexponential model of IVIM-DWI adopted multiple b values for quantitative analysis of the water molecules diffused in the tissue. It could be used as a noninvasive and valuable method for assessment of liver fibrosis.

Basement Membrane Type IV Collagen and Laminin: An Overview of Their Biology and Value as Fibrosis Biomarkers of Liver Disease

Basement membranes provide structural support to epithelium, endothelium, muscles, fat cells, Schwann cells, and axons. Basement membranes are multifunctional: they modulate cellular behavior, regulate organogenesis, promote tissue repair, form a barrier to filtration and tumor metastasis, bind growth factors, and mediate angiogenesis. All basement membranes contain type IV collagen (Col IV), laminin, nidogen, and perlecan. Col IV and laminin self-assemble into two independent supramolecular networks that are linked to nidogen and perlecan to form a morphological discernable basement membrane/basal lamina. The triple helical region, 7S domain and NCI domain of Col IV, laminin and laminin fragment P1 have been evaluated as noninvasive fibrosis biomarkers of alcoholic liver disease, viral hepatitis, and nonalcoholic fatty liver disease. Elevated serum Col IV and laminin are related to degrees of fibrosis and severity of hepatitis, and may reflect hepatic basement membrane metabolism. But the serum assays have not been linked to disclosing the anatomical sites and lobular distribution of perisinusoidal basement membrane formation in the liver. Hepatic sinusoids normally lack a basement membrane, although Col IV is a normal matrix component of the space of Disse. In liver disease, laminin deposits in the space of Disse and codistributes with Col IV, forming a perisinusoidal basement membrane. Concomitantly, the sinusoidal endothelium loses its fenestrae and is transformed into vascular type endothelium. These changes lead to capillarization of hepatic sinusoids, a significant pathology that impairs hepatic function. Accordingly, codistribution of Col IV and laminin serves as histochemical marker of perisinusoidal basement membrane formation in liver disease. Anat Rec, 300:1371-1390, 2017. © 2017 Wiley Periodicals, Inc.

Evaluation of liver fibrosis: "Something old, something new…"

Hepatic fibrogenesis may gradually result to cirrhosis due to the accumulation of extracellular matrix components as a response to liver injury. Thus, therapeutic decisions in chronic liver disease, regardless of the cause, should first and foremost be guided by an accurate quantification of hepatic fibrosis. Detection and assessment of the extent of hepatic fibrosis represent a challenge in modern Hepatology. Although traditional histological staging systems remain the “best standard”, they are not able to quantify liver fibrosis as a dynamic process and may not accurately substage cirrhosis. This review aims to compare the currently used non-invasive methods of measuring liver fibrosis and provide an update in current tissue-based digital techniques developed for this purpose, that may prove of value in daily clinical practice.

Management of patients with hepatitis B in special populations

The development of effective nucleos(t)ide analogs (NAs) against hepatitis B virus (HBV) has improved the outcome of patients with chronic hepatitis B (CHB). This review updates issues related to the management of CHB patients included in special populations. Entecavir (ETV) and tenofovir (TDF) represent the currently recommended first-line NAs in patients with HBV decompensated cirrhosis. The combination of HBV immunoglobulin (usually for a finite duration) and NA is considered the standard of care for prophylaxis against HBV recurrence after liver transplantation. TDF is the best choice for hemodialysis patients and in patients with chronic kidney disease with nucleoside resistance. ETV and telbivudine are the preferred options in naïve renal transplant recipients and with low viremia levels, respectively. All hepatitis B surface antigen (HBsAg)-positive candidates should be treated with NAs before renal transplantation to achieve undetectable HBV DNA at the time of transplantation. Conventional interferon or NAs can also be used in children, on the basis of well-established therapeutic indication. Pregnant women at high risk of perinatal transmission could be treated with lamivudine, telbivudine or TDF in the last trimester of pregnancy. HBsAg-positive patients under immunosuppression should receive NA pre-emptively (regardless of HBV DNA levels) up to 12 mo after its cessation. In HBsAg negative, anti-HBc positive patients under immunosuppression, further studies are needed to form a final conclusion; however, it seems that anti-HBV prophylaxis is justified in such patients with hematological diseases and/or for those receiving rituximab-containing regimens, regardless of their anti-HBs or serum HBV DNA status.

The relationship between transient elastography and histological collagen proportionate area for assessing fibrosis in chronic viral hepatitis

BACKGROUND

Collagen proportionate area (CPA) has a better correlation with hepatic venous pressure gradient (HVPG) than with Ishak stage. Liver stiffness measurement (LSM) is proposed as non invasive marker of portal hypertension/disease progression. Our aim was to compare LSM and CPA with Ishak staging in chronic viral hepatitis, and HVPG in HCV hepatitis after transplantation.

METHODS

One hundred and sixty-nine consecutive patients with chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infections pre/post liver transplantation (LT), had a liver biopsy combined with LSM (transient elastography), CPA (biopsies stained with Sirius Red and evaluated by digital image analysis and expressed as CPA) and HVPG (measured contemporaneously with transjugular biopsies in LT HCV patients).

RESULTS

LSM was dependent on CPA in HBV (r (2) = 0.61, p < 0.0001), HCV (r (2) = 0.59, p < 0.0001) and LT groups (r (2) = 0.64, p < 0.0001). In all three groups, CPA and Ishak were predictors of LSM, but multivariately CPA was better related to LSM (HBV: r (2) = 0.61, p < 0.0001; HCV: r (2) = 0.59, p < 0.0001; post-LT: r (2) = 0.68, p < 0.0001) than Ishak stage. In the LT group, multiple regression analysis including HVPG, LSM, aspartate aminotransferase to platelet ratio index (APRI) and Ishak stage/grade, showed that only CPA was related to HVPG (r (2) = 0.41, p = 0.01), both for HVPG ≥6 mmHg (OR 1.34, 95 % CI 1.14-1.58; p < 0.0001) or ≥10 mmHg (OR 1.25, 95 % CI 1.06-1.47; p = 0.007).

CONCLUSION

CPA was related to LSM in HBV or HCV hepatitis pre/post-LT. CPA was better related to LSM than Ishak stage. In the LT HCV group, CPA was better related to HVPG than Ishak stage/grade, LSM or APRI. CPA may represent a better comparative histological index for LSM, rather than histological stages.

Liver collagen proportionate area predicts decompensation in patients with recurrent hepatitis C virus cirrhosis after liver transplantation

BACKGROUND AND AIMS

Current histological scoring systems do not subclassify cirrhosis. Computer-assisted digital image analysis (DIA) of Sirius Red-stained sections measures fibrosis morphologically producing a fibrosis ratio (collagen proportionate area [CPA]). CPA could have prognostic value within a disease stage, such as cirrhosis. The aim of the present study was to evaluate CPA in patients with recurrent hepatitis C virus (HCV) allograft cirrhosis and assess its relationship with hepatic venous pressure gradient (HVPG).

METHODS

In 121 consecutively-transplanted HCV patients with HVPG, measured contemporaneously with transjugular liver biopsies, 65 had Ishak stage 5 or 6 disease (43 with HVPG measurement). Biopsies were stained with Sirius Red for DIA, and the collagen content was expressed as a CPA. In three cases, a tissue for Sirius Red staining was not obtained, and the patients were excluded.

RESULTS

Sixty-two patients were analyzed. The median HVPG was 8 mmHg (interquartile range [IQR]: 5-10). Portal hypertension (HVPG ≥ 6 < 10 mmHg) was present in 30 (69.8%), and HVPG ≥ 10 mmHg in 13 (30.2%). The median CPA was 16% (IQR 10.75-23.25). Median Child-Pugh score and HVPG were not significantly different between Ishak fibrosis stage 5 or 6, whereas CPA was statistically different: 13% in stage 5 (IQR 8.3-12.4) versus 23% in stage 6 (IQR 17-33.7, P < 0.001). In the multivariate analysis, CPA was the only variable significantly associated with clinically-significant portal hypertension (HVPG ≥ 10 mmHg, odds ratio: 1.085, confidence interval: 1.004-1.172, P = 0.040). A CPA of 14% was the best cut-off value for clinically-significant portal hypertension (CSPH) and liver decompensation, which occurred in 24 patients. Event-free survival was significantly shorter in patients with CSPH or with a CPA value ≥ 14%, or with a combination of both.

CONCLUSION

In Ishak stages 5 and 6, CPA correlated with HVPG, but had a wider range of values, suggesting a greater sensitivity for distinguishing "early" from "late" severe fibrosis/cirrhosis. CPA was a unique, independent predictor of HVPG ≥ 10 mmHg. CPA can be used to subclassify cirrhosis and for prognostic stratification.

Markers of inflammation and fibrosis in alcoholic hepatitis and viral hepatitis C

High levels of profibrinogenic cytokine transforming factor beta (TGF-β), metalloprotease (MMP2), and tissue inhibitor of matrix metalloprotease 1 (TIMP1) contribute to fibrogenesis in hepatitis C virus (HCV) infection and in alcohol-induced liver disease (ALD). The aim of our study was to correlate noninvasive serum markers in ALD and HCV patients with various degrees of inflammation and fibrosis in their biopsies. Methods. Serum cytokines levels in HCV-infected individuals in the presence or absence of ALD were measured. Student's-t-test with Bonferroni correction determined the significance between the groups. Results. Both tumor-necrosis-factor- (TNF)-α and TGF-β levels increased significantly with the severity of inflammation and fibrosis. TGF-β levels increased significantly in ALD patients versus the HCV patients. Proinflammatory cytokines' responses to viral and/or toxic injury differed with the severity of liver inflammation. A combination of these markers was useful in predicting and diagnosing the stages of inflammation and fibrosis in HCV and ALD. Conclusion. Therapeutic monitoring of TGF-β and metalloproteases provides important insights into fibrosis.

Serum surrogate markers of liver fibrosis in primary biliary cirrhosis

BACKGROUND

Hyaluronan, leptin, laminin and collagen IV have been used extensively for the assessment of liver fibrosis. The aim of this study was to assay these markers in the peripheral and hepatic vein blood of primary biliary cirrhosis (PBC) patients and to study their ability to discriminate early from advanced disease.

METHODS

Sera from 62 PBC patients were compared to 60 controls, 44 chronic Hepatitis C, 38 hepatocellular carcinoma and 34 viral cirrhosis patients. Serum from the hepatic vein of 15 cirrhotic PBC patients and 17 patients with viral cirrhosis was also assayed.

RESULTS

All disease groups had significantly increased levels of hyaluronan and collagen IV, compared to controls, while laminin was significantly increased only in viral cirrhosis. Hyaluronan levels were statistically different between early (54.5 ng/ml; 95%CI 27.3-426.9) and late PBC (154.5 ng/ml; 95%CI 55.3-764.4, p<0.05). The area under the curve (AUC) for the identification of late PBC was 0.74 for hyaluronan, 0.63 for leptin, 0.59 for laminin and 0.70 for collagen IV. Hyaluronan had high sensitivity and NPV in identifying late stages of PBC (96% and 90%, respectively). Short term UDCA had no effect on these markers.

CONCLUSION

No single measurement can differentiate between advanced and early fibrosis in PBC. However serum hyaluronan is a promising single serum marker for longitudinal studies in PBC.

Noninvasive tests for evaluation of fibrosis in HCV recurrence after liver transplantation: a systematic review

Noninvasive tests (NIT) for evaluation of hepatic fibrosis have not been evaluated extensively in liver transplantation. We systematically reviewed the literature regarding NIT after liver transplantation. We identified 14 studies evaluating NIT based on serum markers and/or liver imaging techniques: 10 studies assessed NIT in recipients with recurrent HCV infection for fibrosis and four studies evaluated predictors of progression of fibrosis in recurrent HCV. Transient Elastography (TE) had good discrimination for significant fibrosis (median AUROC: 0.88). Among the serum NIT, APRI had good performance (median AUROC: 0.75). TE performed better than serum (direct and indirect) NIT for significant fibrosis with median AUROC 0.88 (vs. 0.66, P < 0.001), median sensitivity 0.86 (vs. 0.56, P = 0.002), median NPV 0.90 (vs. 0.74, P = 0.05) and median PPV 0.80 (vs. 0.63, P = 0.02). TE compared to indirect serum NIT, had better performance, but was not superior to APRI score. Finally, direct, compared to indirect NIT, were not significantly different except for specificity: median: 0.83 vs. 0.69, respectively, P = 0.04. In conclusion, NIT could become an important tool in clinical management of liver transplant recipients, but whether they can improve clinical practice needs further evidence. Their optimal combination with liver biopsy and assessment of collagen content requires investigation.

A fourth dimension in decision making in hepatology

Today, the assessment of liver function in patients suffering from acute or chronic liver disease is based on liver biopsy and blood tests including synthetic function, liver enzymes and viral load, most of which provide only circumstantial evidence as to the degree of hepatic impairment. Most of these tests lack the degree of sensitivity to be useful for follow-up of these patients at the frequency that is needed for decision making in clinical hepatology. Accurate assessment of liver function is essential to determine both short- and long-term prognosis, and for making decisions about liver and non-liver surgery, TIPS, chemoembolization or radiofrequency ablation in patients with chronic liver disease. Liver function tests can serve as the basis for accurate decision-making regarding the need for liver transplantation in the setting of acute failure or in patients with chronic liver disease. The liver metabolic breath test relies on measuring exhaled (13) C tagged methacetin, which is metabolized only by the liver. Measuring this liver-specific substrate by means of molecular correlation spectroscopy is a rapid, non-invasive method for assessing liver function at the point-of-care. The (13) C methacetin breath test (MBT) is a powerful tool to aid clinical hepatologists in bedside decision-making. Our recent findings regarding the ability of point-of-care (13) C MBT to assess the hepatic functional reserve in patients with acute and chronic liver disease are reviewed along with suggested treatment algorithms for common liver disorders.

The relationship between liver disease stage and liver fibrosis: a tangled web

The structural consequences of chronic liver disease are described as a series of liver disease 'stages' with scarring and architectural change that eventually destroys and replaces the normal lobular structure of the liver. Fibrosis ('excess collagen') and stage have been confused in histological staging systems. Fibrosis is part of increasing liver disease stage, but fibrosis and stage are different. Staging liver disease is important in routine histopathological assessment. Measurement of liver fibrosis is another process. The collagenous proportion of a liver biopsy [collagen proportionate area (CPA)] correlates with hepatic venous pressure gradient (HVPG), which is of recognized prognostic value. CPA at 1 year post-transplantation in hepatitis C virus-infected patients predicts subsequent clinical decompensation. CPA in cirrhotic patients predicts decompensation more accurately than staging or HVPG. The 'cirrhosis' stage category has poor prognostic power, and CPA effectively substages cirrhosis. CPA improves the description of liver disease stage. Proper validation of antifibrotic treatments and 'non-invasive markers of liver fibrosis' requires measurement of liver fibrosis (and not liver biopsy stage scores). It is unacceptable for the words 'fibrosis' and 'score' to remain next to each other. There are benefits to properly understanding liver fibrosis and liver disease stage and properly assessing each of them.

Noninvasive markers of fibrosis and inflammation in clinical practice: prospective comparison with liver biopsy

BACKGROUND

The efficiency of transient elastography for the assessment of liver fibrosis has been evaluated mainly in patients with chronic hepatitis C and chronic hepatitis B, with few studies with nonviral chronic liver disease (CLD) such as autoimmune hepatitis, alcoholic liver disease and nonalcoholic steatohepatitis. In this study, we examined the value of transient elastography in a number of groups in comparison with the Fibrotest/Actitest (FT/AT), using the liver biopsy (LB) as the reference standard.

METHODS

An unselected and consecutive group of 65 patients had an LB either as part of an initial diagnosis or of a follow-up assessment, and in addition had a transient elastography measurement [Fibroscan (FS)] and serum blood tests FT/AT performed before the LB. The group consisted of patients diagnosed with a variety of CLD: chronic hepatitis C (n=27), chronic hepatitis B (n=8), alcoholic liver disease (n=14), autoimmune hepatitis (n=13) and nonalcoholic steatohepatitis (n=4).

RESULTS

FS optimal cutoff values were 9.70 kPa for F at least 2, 13.00 kPa for F at least 3, and 16.00 kPa for F=4. The areas under the receiver operating characteristic curve of FS and FT for F at least 2 were 0.88 versus 0.78 in the viral CLD group and 0.81 versus 0.70 in the nonviral CLD group and 0.87 versus 0.80 in all patients. The areas under the receiver operating characteristic curve for A at least 2 in all patients was 0.83. The optimal cutoff for A at least 2 was 0.50.

CONCLUSION

FT/AT is a reliable method for predicting significant liver fibrosis and necroinflammation in both viral and nonviral CLD patients with a value measurement comparable with that of the FS.

Assessment of liver function in acute or chronic liver disease by the methacetin breath test: a tool for decision making in clinical hepatology

Patients suffering from acute or chronic liver disease require on-going assessment of disease progression in terms of the degree of hepatic fibrosis and overall liver impairment. This assessment is pivotal for determining the prognosis and for making decisions about medical treatment and liver transplantation. Currently available methods are either invasive, lack diagnostic accuracy or are limited by technical difficulties such as obesity or biochemical confounders. The metabolic breath test relies on the measurement of tagged metabolites of an organ-specific substrate in the exhaled breath. (13)C-methacetin is metabolized uniquely by the liver, and (13)CO(2) is measured continuously in the exhaled breath. Measuring this liver-specific substrate using molecular correlation spectroscopy provides a rapid, point-of-care, non-invasive method to assess liver function. The use of the (13)C-methacetin breath test (MBT) may provide a powerful tool for clinical hepatologists in decision making at the bedside. This paper reviews recent findings regarding the ability of the point-of-care (13)C-MBT to assess fibrosis, cirrhosis and hepatic functional reserve in patients with acute and chronic liver disease.

Review article: the therapeutic and prognostic benefit of portal pressure reduction in cirrhosis

BACKGROUND

Hepatic venous pressure gradient (HVPG) measurement is not a routinely used technique, despite its therapeutic and prognostic value.

AIM

To review the role of HVPG from published literature.

METHODS

Systematic literature review.

RESULTS

In acute variceal bleeding, HVPG is prognostic identifying 'difficult to treat' group, which now has defined clinical correlations. In secondary prevention of portal hypertensive bleeding, a reduction to < or = 12 mmHg confers near complete protection against rebleeding. The target of > or = 20% HVPG reduction from baseline needs prospective assessment to test a change of therapy, if no reduction occurs. The acute HVPG response to beta-blockade needs further assessment. In primary prevention, the cost-effectiveness of HVPG measurement is not favourable given the efficacy of medical therapy. In chronic liver disease, wedge hepatic venous pressure (WHVP) is prognostic for survival. Pharmacological reduction in portal pressure decreases complications and improves survival, possibly independent of a concomitant improvement in liver function. This latter requires urgent confirmation as it is clinically very relevant. HVPG monitoring can be used to assess anti-viral therapy particularly in cirrhosis, ergonomically combined with transjugular biopsy.

CONCLUSIONS

The prognostic and therapeutic value of HVPG is established beyond portal hypertensive bleeding for which there are some clinical surrogates. HVPG measurement should now be part of everyday clinical practice.

A continuous 13C methacetin breath test for noninvasive assessment of intrahepatic inflammation and fibrosis in patients with chronic HCV infection and normal ALT

Up to 30% of patients with hepatitis C virus (HCV) infection and normal serum alanine aminotransferase (NALT) have significant liver disease. Currently, many of these patients undergo a liver biopsy to guide therapeutic decisions. The BreathID continuous online (13)C-methacetin breath test (MBT) reflects hepatic microsomal function and correlates with hepatic fibrosis. To assess its role in identifying intrahepatic inflammation and fibrosis in NALT patients, we tested 100 patients with untreated chronic HCV infection, and 100 age- and sex-matched healthy volunteers using (13)C MBT following ingestion of 75 mg methacetin. All HCV patients had undergone a liver biopsy within 12 months of performing the MBT. Patients with a necroinflammatory grade <or=4 or >4, based on Ishak (modified HAI) score, HAIa + HAIb + HAIc + HAId, were defined as having low or high inflammation, respectively. Patients with a histological activity fibrosis stage <or=2 or >2, were defined as having nonsignificant or significant fibrosis, respectively. A proprietary algorithm to differentiate intrahepatic inflammation within chronic HCV patients with NALT achieved an area under the curve (AUC) of 0.90. Setting a threshold on the point of best agreement (at 83%) results in 82% sensitivity and 84% specificity. With application of another proprietary algorithm to differentiate patients with nonsignificant or significant fibrosis, 67% of liver biopsies performed in the patient group could have been avoided. This algorithm achieved an AUC of 0.92, with a sensitivity of 91% and a specificity of 88%. There was no correlation between body mass index (BMI) and MBT scores for patients with the same histological score. The continuous BreathID(13)C MBT is an accurate tool for measuring the degree of inflammation and fibrosis in patients with chronic HCV infection and NALT. As such, it may prove to be a powerful, noninvasive alternative to liver biopsy in the management of this patient population.

Bioelectrical impedance analysis for the evaluation of hepatic fibrosis in patients with chronic hepatitis C infection

Bioelectrical impedance analysis (BIA) is a non-invasive technique that measures electrical resistance (R) and reactance (Xc), which are then used to calculate phase angle (PA). The aim of this pilot study was to assess whether BIA can differentiate between minimal and advanced hepatic fibrosis in patients with chronic hepatitis C (HCV) infection. Twenty patients with HCV participated in this study, and were divided into minimal (Metavir 1) and advanced (Metavir 3 or 4) fibrosis groups. We obtained BIA measurements (R and Xc) in several axes and calculated PA from each pair of measurements. We found no statistically significant differences between the two groups with respect to PA, R, or Xc for the whole body, the trunk or the right upper quadrant measurements in any axis. Mean whole body PA was 7.0 and 7.1 (P = 0.9) in the minimal and advanced fibrosis groups, respectively. Bioelectrical impedance analysis did not demonstrate the ability to distinguish between minimal and advanced degrees of hepatic fibrosis in patients with chronic HCV infection.

A clinical and histopathologic perspective on evolving noninvasive and invasive alternatives for liver biopsy

Noninvasive or minimally invasive alternatives are proposed as substitutes for liver biopsy and include clinical indices, cross-sectional imaging, serum biomarkers, liver stiffness measurement, and portal pressure measurement. Most alternatives to liver biopsy assess one aspect of liver disease and translate this into a numeric score. Overlap between categories may limit applications. Liver biopsy provides information about numerous variables: tissue architectural changes; necroinflammatory injury; fibrotic stage; alterations of parenchyma and bile duct epithelium; accumulation of fat, copper, and iron; and molecular and genetic changes. Liver biopsy may identify multiple disease etiologies. A single numeric score cannot be a substitute for complete histologic assessment. However, within defined clinical contexts, noninvasive assessment is an attractive alternative for many patients given the ease, avoidance of risk from invasive procedures, and validated contribution to clinical management. Serum biomarkers and liver stiffness assessment may become indispensable in longitudinal studies and to document outcome of treatments. The accuracy of the more reliable techniques is typically around 80%. Neither liver biopsy nor any single alternative option represents an absolute assessment of liver disease. Biopsy and alternatives are not mutually exclusive options. Liver biopsy and the noninvasive alternatives require a clear understanding of significance and limitations of each investigation. This places a responsibility on the clinician to consider fully the results of any of the investigative options used within the diagnostic and prognostic context of each individual patient, and to choose critically the most appropriate investigations for the patient's needs.

Value of fibrosis markers for staging liver fibrosis in patients with precirrhotic alcoholic liver disease

BACKGROUND

Our aim was to identify markers predictive of fibrosis in alcoholic liver disease (ALD). Percutaneous liver biopsy is the recommended standard for histologic assessment of liver fibrosis. Seven serum markers (tissue inhibitor of matrix metalloproteinase 1 [TIMP1], tenascin, collagen VI, amino-terminal propeptide of type III collagen [PIIINP], matrix metalloproteinases [MMP2], laminin, and hyaluronic acid [HA]) representing various aspects of collagen and extracellular matrix deposition and degradation, have been proposed as noninvasive surrogates for liver biopsy. Moreover, a diagnostic algorithm including 3 serum markers (TIMP1, PIIINP, HA) and age has been proposed to accurately detect fibrosis with acceptable levels of sensitivity/specificity in a chronic hepatitis C subgroup.

METHODS

To determine variability of these markers in liver fibrosis with different etiologies, we conducted an evaluation of their correlative properties in a subgroup of patients (n = 247) with biopsy confirmed liver fibrosis resulting from long-term heavy alcohol consumption. Patients were participants in a recently completed VA multicenter clinical trial followed over 2 years with liver biopsy at baseline and 24 months, and with markers assessed every 3 months.

RESULTS

Among the markers measured in this alcoholic subgroup all except collagen VI displayed significant correlation with degrees of fibrosis. Three markers, TIMP1, PIIINP and HA adjusted for age, emerged as the most promising predictors of the degree of fibrosis in a population of alcoholics. However, there was little change over time as related to change in fibrosis. The lower than expected accuracy of these markers based on receiver operating curves (ROC) also showed their limited use in this etiologic subgroup.

CONCLUSION

In alcoholic patients, various markers have limited value in predicting and diagnosing the stages of fibrosis compared to liver biopsy. Thus, further prospective studies are required to better define the usefulness of each marker or their combination which are possibly affected by alcohol metabolism.

Separation of advanced from mild fibrosis in diffuse liver disease using 31P magnetic resonance spectroscopy

31P-MRS using DRESS was used to compare absolute liver metabolite concentrations (PME, Pi, PDE, gammaATP, alphaATP, betaATP) in two distinct groups of patients with chronic diffuse liver disorders, one group with steatosis (NAFLD) and none to moderate inflammation (n=13), and one group with severe fibrosis or cirrhosis (n=16). All patients underwent liver biopsy and extensive biochemical evaluation. A control group (n=13) was also included. Absolute concentrations and the anabolic charge, AC=[PME]/([PME]+[PDE]), were calculated. Comparing the control and cirrhosis groups, lower concentrations of PDE (p=0.025) and a higher AC (p<0.001) were found in the cirrhosis group. Also compared to the NAFLD group, the cirrhosis group had lower concentrations of PDE (p=0.01) and a higher AC (p=0.009). No significant differences were found between the control and NAFLD group. When the MRS findings were related to the fibrosis stage obtained at biopsy, there were significant differences in PDE between stage F0-1 and stage F4 and in AC between stage F0-1 and stage F2-3. Using a PDE concentration of 10.5mM as a cut-off value to discriminate between mild, F0-2, and advanced, F3-4, fibrosis the sensitivity and specificity were 81% and 69%, respectively. An AC cut-off value of 0.27 showed a sensitivity of 93% and a specificity of 54%. In conclusion, the results suggest that PDE is a marker of liver fibrosis, and that AC is a potentially clinically useful parameter in discriminating mild fibrosis from advanced.