Relationships between fibrosis amounts assessed by morphometry and liver stiffness measurements in chronic hepatitis or steatohepatitis

Noninvasive assessment of liver disease severity in patients with nonalcoholic fatty liver disease (NAFLD) and type 2 diabetes

BACKGROUND AND AIMS

We evaluated the diagnostic accuracy of simple, noninvasive tests (NITs) in NAFLD patients with type 2 diabetes (T2D).

METHODS AND RESULTS

This was an individual patient data meta-analysis of 1780 patients with biopsy-proven NAFLD and T2D. The index tests of interest were FIB-4, NAFLD Fibrosis Score (NFS), aspartate aminotransferase-to-platelet ratio index, liver stiffness measurement (LSM) by vibration-controlled transient elastography, and AGILE 3+. The target conditions were advanced fibrosis, NASH, and fibrotic NASH(NASH plus F2-F4 fibrosis). The diagnostic performance of noninvasive tests. individually or in sequential combination, was assessed by area under the receiver operating characteristic curve and by decision curve analysis. Comparison with 2278 NAFLD patients without T2D was also made. In NAFLD with T2D LSM and AGILE 3+ outperformed, both NFS and FIB-4 for advanced fibrosis (area under the receiver operating characteristic curve:LSM 0.82, AGILE 3+ 0.82, NFS 0.72, FIB-4 0.75, aspartate aminotransferase-to-platelet ratio index 0.68; p < 0.001 of LSM-based versus simple serum tests), with an uncertainty area of 12%-20%. The combination of serum-based with LSM-based tests for advanced fibrosis led to a reduction of 40%-60% in necessary LSM tests. Decision curve analysis showed that all scores had a modest net benefit for ruling out advanced fibrosis at the risk threshold of 5%-10% of missing advanced fibrosis. LSM and AGILE 3+ outperformed both NFS and FIB-4 for fibrotic NASH (area under the receiver operating characteristic curve:LSM 0.79, AGILE 3+ 0.77, NFS 0.71, FIB-4 0.71; p < 0.001 of LSM-based versus simple serum tests). All noninvasive scores were suboptimal for diagnosing NASH.

CONCLUSIONS

LSM and AGILE 3+ individually or in low availability settings in sequential combination after FIB-4 or NFS have a similar good diagnostic accuracy for advanced fibrosis and an acceptable diagnostic accuracy for fibrotic NASH in NAFLD patients with T2D.

Diagnostic accuracy of non-invasive tests for advanced fibrosis in patients with NAFLD: an individual patient data meta-analysis

OBJECTIVE

Liver biopsy is still needed for fibrosis staging in many patients with non-alcoholic fatty liver disease. The aims of this study were to evaluate the individual diagnostic performance of liver stiffness measurement by vibration controlled transient elastography (LSM-VCTE), Fibrosis-4 Index (FIB-4) and NAFLD (non-alcoholic fatty liver disease) Fibrosis Score (NFS) and to derive diagnostic strategies that could reduce the need for liver biopsies.

DESIGN

Individual patient data meta-analysis of studies evaluating LSM-VCTE against liver histology was conducted. FIB-4 and NFS were computed where possible. Sensitivity, specificity and area under the receiver operating curve (AUROC) were calculated. Biomarkers were assessed individually and in sequential combinations.

RESULTS

Data were included from 37 primary studies (n=5735; 45% women; median age: 54 years; median body mass index: 30 kg/m²; 33% had type 2 diabetes; 30% had advanced fibrosis). AUROCs of individual LSM-VCTE, FIB-4 and NFS for advanced fibrosis were 0.85, 0.76 and 0.73. Sequential combination of FIB-4 cut-offs (<1.3; ≥2.67) followed by LSM-VCTE cut-offs (<8.0; ≥10.0 kPa) to rule-in or rule-out advanced fibrosis had sensitivity and specificity (95% CI) of 66% (63-68) and 86% (84-87) with 33% needing a biopsy to establish a final diagnosis. FIB-4 cut-offs (<1.3; ≥3.48) followed by LSM cut-offs (<8.0; ≥20.0 kPa) to rule out advanced fibrosis or rule in cirrhosis had a sensitivity of 38% (37-39) and specificity of 90% (89-91) with 19% needing biopsy.

CONCLUSION

Sequential combinations of markers with a lower cut-off to rule-out advanced fibrosis and a higher cut-off to rule-in cirrhosis can reduce the need for liver biopsies.

Diagnostic accuracy of elastography and magnetic resonance imaging in patients with NAFLD: A systematic review and meta-analysis

BACKGROUND AND AIMS

Vibration-controlled transient elastography (VCTE), point shear wave elastography (pSWE), 2-dimensional shear wave elastography (2DSWE), magnetic resonance elastography (MRE), and magnetic resonance imaging (MRI) have been proposed as non-invasive tests for patients with non-alcoholic fatty liver disease (NAFLD). This study evaluated their diagnostic accuracy for liver fibrosis and non-alcoholic steatohepatitis (NASH).

METHODS

PubMED/MEDLINE, EMBASE and the Cochrane Library were searched for studies examining the diagnostic accuracy of these index tests, against histology as the reference standard, in adult patients with NAFLD. Two authors independently screened and assessed methodological quality of studies and extracted data. Summary estimates of sensitivity, specificity and area under the curve (sAUC) were calculated for fibrosis stages and NASH, using a random effects bivariate logit-normal model.

RESULTS

We included 82 studies (14,609 patients). Meta-analysis for diagnosing fibrosis stages was possible in 53 VCTE, 11 MRE, 12 pSWE and 4 2DSWE studies, and for diagnosing NASH in 4 MRE studies. sAUC for diagnosis of significant fibrosis were: 0.83 for VCTE, 0.91 for MRE, 0.86 for pSWE and 0.75 for 2DSWE. sAUC for diagnosis of advanced fibrosis were: 0.85 for VCTE, 0.92 for MRE, 0.89 for pSWE and 0.72 for 2DSWE. sAUC for diagnosis of cirrhosis were: 0.89 for VCTE, 0.90 for MRE, 0.90 for pSWE and 0.88 for 2DSWE. MRE had sAUC of 0.83 for diagnosis of NASH. Three (4%) studies reported intention-to-diagnose analyses and 15 (18%) studies reported diagnostic accuracy against pre-specified cut-offs.

CONCLUSIONS

When elastography index tests are acquired successfully, they have acceptable diagnostic accuracy for advanced fibrosis and cirrhosis. The potential clinical impact of these index tests cannot be assessed fully as intention-to-diagnose analyses and validation of pre-specified thresholds are lacking.

LAY SUMMARY

Non-invasive tests that measure liver stiffness or use magnetic resonance imaging (MRI) have been suggested as alternatives to liver biopsy for assessing the severity of liver scarring (fibrosis) and fatty inflammation (steatohepatitis) in patients with non-alcoholic fatty liver disease (NAFLD). In this study, we summarise the results of previously published studies on how accurately these non-invasive tests can diagnose liver fibrosis and inflammation, using liver biopsy as the reference. We found that some techniques that measure liver stiffness had a good performance for the diagnosis of severe liver scarring.

Serum cytokeratin-18 and its relation to liver fibrosis and steatosis diagnosed by FibroScan and controlled attenuation parameter in nonalcoholic fatty liver disease and hepatitis C virus patients

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) has emerged as the most common cause of chronic liver disease worldwide. Multiple diagnostic noninvasive methods for NAFLD were studied (both serological and imaging), either single or combined. Attention has been focused on cytokeratin-18 (CK18) as a novel serological marker for the diagnosis of steatosis/fibrosis in NAFLD and hepatitis C virus (HCV) patients.

AIM

The aim of this study was to evaluate serum CK18 in NAFLD and HCV fibrosis/steatosis and also to correlate its performance with the diagnostic accuracy of transient elastography (TE) and controlled attenuation parameter (CAP) in the diagnosis of fibrosis/steatosis in these patients.

PATIENTS AND METHODS

Three equal groups of participants were enrolled (n=135): group I included patients with chronic HCV, group II included NAFLD patients, and group III included control participants. For all groups, TE/CAP and labs including serum CK18 were performed. Liver biopsy was performed for the NAFLD group.

RESULTS

Serum CK18 was significantly higher in the NAFLD group (19.01±3.49 ng/ml) versus the HCV group (8.95±1.06 ng/ml) and the control group (4.83±1.6 ng/ml) (P<0.001). The CK18 levels in biopsy stages (steatosis, ballooning, inflammation, and fibrosis) and FibroScan/CAP degrees showed that CK18 increased significantly with steatosis and fibrosis stages (biopsy or FibroScan/CAP), but did not reach significance with ballooning or inflammation grades. CK18 was significantly different in nonalcoholic steatohepatitis versus non-nonalcoholic steatohepatitis patients (P=0.041). The best CK18 cutoff to detect steatosis (S≥2) in NAFLD and HCV was 11.65 and 6.84 ng/ml, respectively with an overall sensitivity and specificity over 97%. The CK18 cutoff for significant fibrosis (F≥2) by FibroScan in the NAFLD/HCV groups was 9.115 ng/ml, with 62.5%/69.2% sensitivity/specificity (P=0.031). However, inflammation had a cutoff with a marginal P value (P=0.080), and a reliable cutoff for ballooning was not attained (P=0.386). There was a positive correlation between CK18 and fibrosis (by FibroScan) in the NAFLD and HCV groups (P<0.05). The correlation between CK18 and steatosis in CAP and the nonalcoholic fatty liver disease activity score was very good (P<0.001).

CONCLUSION

Serum CK18 is related strongly to the development/progression of NAFLD and HCV-related fibrosis/steatosis. TE was correlated highly with liver biopsy results. The combination of CK18 with other noninvasive modalities increases the diagnostic yield of these tests.

Ultrasound elastography as an imaging biomarker for detection of early tumor response to chemotherapy in a murine breast cancer model: a feasibility study

OBJECTIVE

This study investigated the feasibility of using strain elastography (SE) and real time shear wave elastography (RT-SWE) to evaluate early tumor response to cytotoxic chemotherapy in a murine xenograft breast cancer tumor model.

METHODS

MCF-7 breast cancer-bearing nude mice were treated with either cisplatin 2 mg kg^-1 plus paclitaxel 10 mg kg^-1 (treatment group) or sterile saline (control group) once daily for 5 days. The tumor elasticity was measured by SE or RT-SWE before and after therapy. Tumor cell density was assessed by hematoxylin and eosin staining, and the ratio of collagen fibers in the tumor was evaluated by Van Gieson staining. The correlation between tumor elasticity, as determined by SE and SWE, as well as the pathological tumor responses were analyzed.

RESULTS

Chemotherapy significantly attenuated tumor growth compared to the control treatment (p < 0.05). Chemotherapy also significantly increased tumor stiffness (p < 0.05) and significantly decreased (p < 0.05) tumor cell density compared with the control. Moreover, chemotherapy significantly increased the ratio of collagen fibers (p < 0.05). Tumor stiffness was positively correlated with the ratio of collagen fibers but negatively correlated with tumor cell density.

CONCLUSION

The study suggests that ultrasound elastography by SE and SWE is a feasible tool for assessing early responses of breast cancer to chemotherapy in our murine xenograft model. Advances in knowledge: This study showed that the tumor elasticity determined by ultrasound elastography could be a feasible imaging biomarker for assessing very early therapeutic responses to chemotherapy.

Comparison of collagen proportionate areas in liver fibrosis quantification between chronic hepatitis B and C

Few studies have compared the distinct hepatic collagen morphometrics of chronic hepatitis B (CHB) and chronic hepatitis C (CHC). This study compared the discrepancies between CHB and CHC in liver fibrosis (F) quantification by using the collagen proportionate area (CPA) and liver stiffness (LS) measured with shear wave velocity (SWV).This study enrolled 274 eligible consecutive patients diagnosed with CHB (n = 137) or CHC (n = 137). Their ages ranged from 20 to 80 years (median = 50). In total, 154 patients (56.2%) were male. Participant LS was measured by using acoustic radiation force impulse elastography preceding an immediate percutaneous liver biopsy. The total proportion of the collagen stained with picrosirius red to the total tissue area was expressed as the CPA percentage, which was stratified into portal-bridging (PB) and perisinusoidal (PS) proportionate areas (PAs).Based on the METAVIR F staging system, 36 (26.3%), 36 (26.3%), 28 (20.4%), and 37 (27.0%) participants in the CHB group and 34 (24.8%), 45 (32.9%), 34 (24.8%), and 24 (17.5%) participants in the CHC group were staged as F1, F2, F3, and F4, respectively. Both the total CPAs and PBPAs were significantly (P < 0.05) higher in the CHC group than in the CHB group within all F-stratified subgroups. The SWVs were significantly (P < 0.05) higher in the CHC group than in the CHB group only within the F2, F3, and F4 subgroups. However, the PSPAs did not differ significantly between the CHC and CHB groups within all subgroups. Multiple regression analysis revealed that viral hepatitis etiology (P < 0.001), METAVIR F stages (P < 0.001), and platelet count (P = 0.007) were independent factors correlated with the CPA (R = 0.543, P < 0.001).In conclusion, both the F stage-stratified CPAs and SWVs tended to be higher in cases of CHC than in those of CHB. The type of viral hepatitis significantly affected both the CPA and SWV values. The PBPAs were more closely correlated with F stages and SWV than were the PSPAs.

Prospective comparison of magnetic resonance imaging to transient elastography and serum markers for liver fibrosis detection

BACKGROUND & AIMS

Establishing accurate non-invasive methods of liver fibrosis quantification remains a major unmet need. Here, we assessed the diagnostic value of a multiparametric magnetic resonance imaging (MRI) protocol including diffusion-weighted imaging (DWI), dynamic contrast-enhanced (DCE)-MRI and magnetic resonance elastography (MRE) in comparison with transient elastography (TE) and blood tests [including ELF (Enhanced Liver Fibrosis) and APRI] for liver fibrosis detection.

METHODS

In this single centre cross-sectional study, we prospectively enrolled 60 subjects with liver disease who underwent multiparametric MRI (DWI, DCE-MRI and MRE), TE and blood tests. Correlation was assessed between non-invasive modalities and histopathologic findings including stage, grade and collagen content, while accounting for covariates such as age, sex, BMI, HCV status and MRI-derived fat and iron content. ROC curve analysis evaluated the performance of each technique for detection of moderate-to-advanced liver fibrosis (F2-F4) and advanced fibrosis (F3-F4).

RESULTS

Magnetic resonance elastography provided the strongest correlation with fibrosis stage (r = 0.66, P < 0.001), inflammation grade (r = 0.52, P < 0.001) and collagen content (r = 0.53, P = 0.036). For detection of moderate-to-advanced fibrosis (F2-F4), AUCs were 0.78, 0.82, 0.72, 0.79, 0.71 for MRE, TE, DCE-MRI, DWI and APRI, respectively. For detection of advanced fibrosis (F3-F4), AUCs were 0.94, 0.77, 0.79, 0.79 and 0.70, respectively.

CONCLUSIONS

Magnetic resonance elastography provides the highest correlation with histopathologic markers and yields high diagnostic performance for detection of advanced liver fibrosis and cirrhosis, compared to DWI, DCE-MRI, TE and serum markers.

Transient elastography compared to liver biopsy and morphometry for predicting fibrosis in pediatric chronic liver disease: Does etiology matter?

AIM: To evaluate transient elastography (TE) as a noninvasive tool in staging liver fibrosis compared with liver biopsy and morphometry in children with different chronic liver diseases.

METHODS: A total of 90 children [50 with chronic hepatitis C virus (HCV), 20 with autoimmune hepatitis (AIH) and 20 with Wilson disease] were included in the study and underwent liver stiffness measurement (LSM) using TE. Liver biopsies were evaluated for fibrosis, qualitatively, by Ishak score and quantitatively by fibrosis area fraction (FAF) using digital image analysis (morphometry). LSM was correlated with fibrosis and other studied variables using spearman correlation. A stepwise multiple regression analysis was also performed to examine independent factors associated with LSM. Different cut-off values of LSM were calculated for predicting individual fibrosis stages using receiver-operating characteristic curve. Cut-off values with optimal clinical performance (optimal sensitivity and specificity simultaneously) were selected.

RESULTS: The majority of HCV group had minimal activity (80%) and no/mild fibrosis (72%). On the other hand, the majority of AIH group had mild to moderate activity (70%) and moderate to severe fibrosis (95%) and all Wilson disease group had mild to moderate activity (100%) and moderate to severe fibrosis (100%). LSM correlated significantly with both FAF and Ishak scores and the correlation appeared better with the latter (r = 0.839 vs 0.879, P < 0.0001 for both). LSM discriminated individual stages of fibrosis with high performance. Sensitivity ranged from 81.4% to 100% and specificity ranged from 75.0% to 97.2%. When we compared LSM values for the same stage of fibrosis, they varied according to the different etiologies. Higher values were in AIH (16.15 ± 7.23 kPa) compared to Wilson disease (8.30 ± 0.84 kPa) and HCV groups (7.43 ± 1.73 kPa). Multiple regression analysis revealed that Ishak fibrosis stage was the only independent variable associated with higher LSM (P < 0.0001).

CONCLUSION: TE appears reliable in distinguishing different stages of liver fibrosis in children. However, its values vary according to the disease type. For that, a disease-specific estimation of cut-off values for fibrosis staging is worthy.

Cytokeratin 18-Aspartate396 apoptotic fragment for fibrosis detection in patients with non-alcoholic fatty liver disease and chronic viral hepatitis

BACKGROUND

The combination of non-invasive markers for the detection of fibrosis in patients with chronic liver diseases is still a matter of debate.

AIMS

To test the performance of cytokeratin18-Aspartate396 alone or in combination with transient elastography as a marker of fibrosis, compared to liver biopsy as gold standard.

METHODS

In 259 prospectively enrolled patients with chronic liver diseases, clinical, biochemical, and histological features were assessed. Serum cytokeratin18-Aspartate396 and Fibroscan were performed within 6 months prior to liver biopsy.

RESULTS

Cytokeratin18-Aspartate396 levels predicted both significant and advanced fibrosis in non-alcoholic fatty liver disease group, correctly identifying 83.7% and 80.8% of cases, respectively. Liver stiffness performed best in predicting severe fibrosis in patients with chronic viral infection, correctly identifying 78.7% of chronic hepatitis B and 88.6% of chronic hepatitis C subjects. The combination of cytokeratin18-Aspartate396 and liver stiffness improved their diagnostic performance for the detection of significant and advanced fibrosis in non-alcoholic fatty liver disease group, only (sensitivity=78.3%, specificity=90.7%; sensitivity=91.7%, specificity=71.6%, respectively).

CONCLUSION

Cytokeratin18-Aspartate396 and liver stiffness can improve the non-invasive prediction of significant and advanced fibrosis in patients with non-alcoholic fatty liver disease, while in hepatitis B and C virus infected patients their combined use had no advantage over the diagnostic accuracy of transient elastography alone.

Noninvasive assessment of alcoholic liver disease using unidimensional transient elastography (Fibroscan®)

Unidimensional transient elastography (TE) is a noninvasive technique, which has been increasingly used in the assessment of diffuse liver diseases. This paper focuses on reviewing the existing data on the use of TE in the diagnosis of fibrosis and in monitoring disease progression in alcoholic liver disease, on the factors that may influence the result of fibrosis prediction, and last but not least, on its potential use in assessing the steatosis degree. Therefore, this field is far from being exhausted and deserves more attention. Further studies are required, on large groups of biopsied patients, in order to find answers to all the remaining questions in this field.

Head-to-Head Comparison between Collagen Proportionate Area and Acoustic Radiation Force Impulse Elastography in Liver Fibrosis Quantification in Chronic Hepatitis C

BACKGROUND

The aim of this study was to compare the diagnostic performances of the collagen proportionate area (CPA) and liver stiffness measurement (LSM) for liver fibrosis quantification in chronic hepatitis C (CHC).

METHODS

A total of 137 eligible consecutive Taiwanese patients (74 women and 63 men; age 21-80 years; median age 54 years), with CHC underwent LSM by using acoustic radiation force impulse (ARFI) elastography and an immediate percutaneous liver biopsy for METAVIR scoring. Liver tissue sections were stained using picrosirius red. Areas of the stained collagen and the tissue parenchyma were calculated in pixels. The ratio between the two areas was expressed as a CPA percentage. The result of LSM was presented as shear wave velocity (SWV).

RESULTS

METAVIR fibrosis (F) stages were dichotomized using the CPA (%) and SWV (m/s), and the optimal cut-off values were 7.47 and 1.59 for F1 versus F2-4; 12.56 and 1.73 for F1, 2 versus F3, 4; 15.32 and 1.96 for F1-3 versus F4. To dichotomize F1 versus F2-4, the areas under receiver operating characteristic curves for the CPA was 0.9349 (95% confidence interval: 0.8943-0.9755) and for SWV was 0.8434 (0.7762-0.9105) (CPA versus SWV, P = 0.0063). For F1, 2 versus F3, 4, the CPA was 0.9436 (0.9091-0.9781); SWV was 0.8997 (0.8444-0.9551) (P = 0.1587). For F1-3 versus F4, the CPA was 0.8647 (0.7944-0.9349); SWV was 0.9036 (0.8499-0.9573) (P = 0.2585). The CPA could be predicted in a linear regression formula by using SWV and platelet count (R2 = 0.524).

CONCLUSIONS

The CPA and ARFI elastography are promising tools for liver fibrosis evaluation. The CPA was superior to ARFI elastography in the diagnosis of significant fibrosis (≥ F2). The CPA may be independent of severe necroinflammation, which may augment liver stiffness.

Head-to-Head Comparison between Collagen Proportionate Area and Acoustic Radiation Force Impulse Elastography in Liver Fibrosis Quantification in Chronic Hepatitis C

BACKGROUND

The aim of this study was to compare the diagnostic performances of the collagen proportionate area (CPA) and liver stiffness measurement (LSM) for liver fibrosis quantification in chronic hepatitis C (CHC).

METHODS

A total of 137 eligible consecutive Taiwanese patients (74 women and 63 men; age 21-80 years; median age 54 years), with CHC underwent LSM by using acoustic radiation force impulse (ARFI) elastography and an immediate percutaneous liver biopsy for METAVIR scoring. Liver tissue sections were stained using picrosirius red. Areas of the stained collagen and the tissue parenchyma were calculated in pixels. The ratio between the two areas was expressed as a CPA percentage. The result of LSM was presented as shear wave velocity (SWV).

RESULTS

METAVIR fibrosis (F) stages were dichotomized using the CPA (%) and SWV (m/s), and the optimal cut-off values were 7.47 and 1.59 for F1 versus F2-4; 12.56 and 1.73 for F1, 2 versus F3, 4; 15.32 and 1.96 for F1-3 versus F4. To dichotomize F1 versus F2-4, the areas under receiver operating characteristic curves for the CPA was 0.9349 (95% confidence interval: 0.8943-0.9755) and for SWV was 0.8434 (0.7762-0.9105) (CPA versus SWV, P = 0.0063). For F1, 2 versus F3, 4, the CPA was 0.9436 (0.9091-0.9781); SWV was 0.8997 (0.8444-0.9551) (P = 0.1587). For F1-3 versus F4, the CPA was 0.8647 (0.7944-0.9349); SWV was 0.9036 (0.8499-0.9573) (P = 0.2585). The CPA could be predicted in a linear regression formula by using SWV and platelet count (R2 = 0.524).

CONCLUSIONS

The CPA and ARFI elastography are promising tools for liver fibrosis evaluation. The CPA was superior to ARFI elastography in the diagnosis of significant fibrosis (≥ F2). The CPA may be independent of severe necroinflammation, which may augment liver stiffness.

The severity of steatosis influences liver stiffness measurement in patients with nonalcoholic fatty liver disease

In nonalcoholic fatty liver disease, the influence of severity of steatosis on liver stiffness measurement (LSM) is poorly studied and still debated. We assessed the impact of steatosis severity and its ultrasonographic (US) sign, severe bright liver echo pattern, on LSM values and on transient elastography accuracy for the diagnosis of liver fibrosis in a cohort of consecutive patients with nonalcoholic fatty liver disease. Patients (n = 253) were assessed by clinical, US, and histological (Kleiner score) features. Transient elastography was performed using the M probe. Among patients with low amounts of fibrosis (F0-F1 and F0-F2), median LSM values, expressed in kilopascals, were significantly higher in subjects with severe steatosis (≥66% at liver biopsy) compared to those without (F0-F1 6.9 versus 5.8, P = 0.04; F0-F2 7.4 versus 6.0, P = 0.001) as well as in patients with severe bright liver echo pattern on US compared to their counterparts (F0-F1 7.3 versus 5.6, P = 0.001; F0-F2 7.6 versus 6.0, P < 0.001). In subjects without significant fibrosis (F0-F1) and without severe fibrosis (F0-F2), a higher rate of false-positive LSM results was observed in patients with steatosis ≥66% compared to those without (F0-F1 23.6% versus 14.9%, F0-F2 33.3% versus 13.2%) and in patients with severe bright liver echo pattern on US (F0-F1 22.2% versus 15.4%, F0-F2 28.8% versus 15.6%) compared to their counterparts.

CONCLUSIONS

In patients with nonalcoholic fatty liver disease, the presence of severe steatosis, detected by histology or by US, should always be taken into account in order to avoid overestimations of liver fibrosis assessed by transient elastography.

The diagnostic accuracy of transient elastography for the diagnosis of liver fibrosis in bariatric surgery candidates with suspected NAFLD

BACKGROUND

Severe obesity and metabolic syndrome have been implicated in the development of nonalcoholic fatty liver disease (NAFLD). We evaluated the diagnostic value of liver stiffness measurement (LSM), by transient elastography (FibroScan®) in bariatric surgery candidates with suspected NAFLD.

METHODS

A total of 100 prospectively included consecutive severely obese subjects underwent bariatric surgery with liver needle biopsy. LSM was performed in the 15 days preceding liver biopsy.

RESULTS

According to Kleiner's classification, 28 patients had no fibrosis, 50 had stage F1 fibrosis, 13 had stage F2 fibrosis, and nine had stage F3 fibrosis. LSMs were higher in patients with fibrosis stage F ≥2, than in patients with a fibrosis stage below F2 (p < 0.001). Fibrosis stage (p < 0.002), amount of steatosis (%) (p < 0.001), BMI (p < 0.02), and activity score (p = 0.027) were independently correlated with LSM. Homeostasis model assessment (HOMA) index was also significantly and independently correlated with LSM (p < 0.01). The area under the receiver operating characteristic curve (AUROC) generated by FibroScan® was 0.81 ± 0.05 for predicting fibrosis stage F ≥2 and 0.85 ± 0.04 for predicting F3 fibrosis. The decrease in LSM 1 year after bariatric surgery was significantly correlated with changes in HOMA index (r = 0.43, p = 0.01), but not with changes in BMI or weight.

CONCLUSION

FibroScan® allows the early diagnosis of fibrosis in severely obese patients. Our results also suggest that FibroScan® could identify a subgroup of NAFLD patients at high risk of progressive liver disease and that LSM could be used as a surrogate marker of insulin resistance. Further studies are required to evaluate the prognostic value of FibroScan®.

Non-invasive score system for fibrosis in chronic hepatitis: proposal for a model based on biochemical, FibroScan and ultrasound data

BACKGROUND & AIMS

We elaborate a non-invasive score system for liver fibrosis (NISF), exploring its diagnostic performance and comparing its accuracy to FibroScan in patients with chronic viral hepatitis (CH) and non-alcoholic fatty liver disease (NAFLD).

METHODS

Clinical, biochemical, elastographic and ultrasound parameters derived from patients with CH (n = 83) or NAFLD (n = 58), undergoing liver biopsy for fibrosis assessment, were prospectively collected as potential predictors of fibrosis. Each parameter was evaluated for its correlation with the liver biopsy (Gold Standard). Candidate predictors with good interobserver agreement and correlation with histological stages were combined into two algorithms (NISF) to predict fibrosis in chronic viral hepatitis and NAFLD.

RESULTS

The CH-NISF included six parameters: bluntness of liver edges, irregularity of left lobe surface, diameter of segment 4, liver stiffness measurement, platelet count and ALT values. The ability of the model to discriminate F3-F4 vs F0-F1 stages and F2 vs F0-F1 was high (AUROC of 0.95 and 0.83 respectively) and better than FibroScan alone, especially in intermediate stages (F2 vs F0-F1), AUROC 0.83 vs 0.57 (P = 0.003). The resulting algorithm is available as mathematical formula, nomogram or free online link. [http://health.mafservizi.it/NISF_Calculator/liver.htm] The NAFLD-NISF included liver stiffness, platelet count and AST levels, had good ability to discriminate F0-F1 vs F2-F3-F4 stages (AUROC 0.86), however, not significantly higher than FibroScan.

CONCLUSIONS

CH-NISF can be proposed as preliminary and easily available staging tool, superior to FibroScan alone in predicting histological fibrosis, especially in intermediate stages. Further validations are needed to improve NISF accuracy in NAFLD.

Evaluation of Histological and non-Invasive Methods for the Detection of Liver Fibrosis: The Values of Histological and Digital Morphometric Analysis, Liver Stiffness Measurement and APRI Score

Prognosis and treatment of liver diseases mainly depend on the precise evaluation of the fibrosis. Comparisons were made between the results of Metavir fibrosis scores and digital morphometric analyses (DMA), liver stiffness (LS) values and aminotransferase-platelet ratio (APRI) scores, respectively. Liver biopsy specimens stained with Sirius red and analysed by morphometry, LS and APRI measurements were taken from 96 patients with chronic liver diseases (56 cases of viral hepatitis, 22 cases of autoimmune- and 18 of mixed origin). The strongest correlation was observed between Metavir score and DMA (r = 0.75 p < 0.05), followed in decreasing order by LS and Metavir (r = 0.61), LS and DMA (r = 0.47) LS and APRI (r = 0.35) and Metavir and APRI (r = 0.24), respectively. DMA is a helpful additional tool for the histopathological evaluation of fibrosis, even when the sample size is small and especially in case of advanced fibrosis. The non-invasive methods showed good correlation with the histopathological methods; LS proved to be more accurate than APRI. The stronger correlation between LS values and Metavir scores, as well as the results of DMA in case of appropriate sample size were remarkable.

Non-invasive methods for the diagnosis of nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is the commonest chronic liver disease and includes simple steatosis and nonalcoholic steatohepatitis (NASH). Since NASH progresses to cirrhosis more frequently and increases liver-related and cardiovascular disease risk substantially more than simple steatosis, there is a great need to differentiate the two entities. Liver biopsy is the gold standard for the diagnosis of NAFLD but its disadvantages, including the risk of complications and sampling bias, stress the need for developing alternative diagnostic methods. Accordingly, several non-invasive markers have been evaluated for the diagnosis of simple steatosis and NASH, including both serological indices and imaging methods. The present review summarizes the current knowledge on the role of these markers in the diagnosis of NAFLD. Current data suggest that ultrasound and the fibrosis-4 score are probably the most appealing methods for detecting steatosis and for distinguishing NASH from simple steatosis, respectively, because of their low cost and relatively high accuracy. However, currently available methods, both serologic and imaging, cannot obviate the need for liver biopsy for diagnosing NASH due to their substantial false positive and false negative rates. Therefore, the current role of these methods is probably limited in patients who are unwilling or have contraindications for undergoing biopsy.

Nonalcoholic fatty liver disease: Noninvasive methods of diagnosing hepatic steatosis

Hepatic steatosis is the buildup of lipids within hepatocytes. It is the simplest stage in nonalcoholic fatty liver disease (NAFLD). It occurs in approximately 30% of the general population and as much as 90% of the obese population in the United States. It may progress to nonalcoholic steatohepatitis, which is a state of hepatocellular inflammation and damage in response to the accumulated fat. Liver biopsy remains the gold standard tool to diagnose and stage NAFLD. However, it comes with the risk of complications ranging from simple pain to life-threatening bleeding. It is also associated with sampling error. For these reasons, a variety of noninvasive radiological markers, including ultrasound, computed tomography, magnetic resonance spectroscopy, and the controlled attenuation parameter using transient elastography and Xenon-133 scan have been proposed to increase our ability to diagnose NAFLD, hence avoiding liver biopsy. The aim of this review is to discuss the utility and accuracy of using available noninvasive diagnostic modalities for fatty liver in NAFLD.

Quantification of portal-bridging fibrosis area more accurately reflects fibrosis stage and liver stiffness than whole fibrosis or perisinusoidal fibrosis areas in chronic hepatitis C

Morphometry provides an objective evaluation of fibrosis in liver diseases. We developed an image analysis algorithm using automated thresholding and segmentation to separately quantify the areas and the fractal dimensions of portal-bridging fibrosis and perisinusoidal fibrosis in chronic hepatitis C liver biopsies. We studied 427 digitized liver biopsies and compared the automated measures of the different fibrosis compartments with (1) the Metavir F (fibrosis) and A (activity) histological scores, (2) the digitally assessed area of steatosis, and (3) the liver stiffness measured by elastography (Fibroscan). The perisinusoidal fibrosis area was higher than that of portal fibrosis in stages ≤F2; it reached its highest value in F2 stage and stabilized thereafter. The F3 stage was characterized by equal proportions of portal-bridging and perisinusoidal fibrosis, whereas portal-bridging area was predominant in cirrhosis. Measurement of portal-bridging fibrosis showed highly significantly different values between contiguous F stages; the ratio of portal-bridging fibrosis/perisinusoidal fibrosis displayed less overlap between Metavir stages than did the whole fibrosis area values. Fractal dimension showed that portal-bridging fibrosis tended to display a homogeneous surface-like spatial organization, whereas perisinusoidal fibrosis appeared more heterogeneous according to stage and curvilinear. The portal-bridging fibrosis area was low in cases with low Metavir activity and little steatosis, and became predominant with increasing activity and steatosis. Using stepwise multiple linear regression analysis, the liver stiffness was independently correlated to the portal-bridging fibrosis area (first step, P<0.001), the steatosis area (second step, P<0.001), and the Metavir A grade (third step, P=0.001), but not to the perisinusoidal fibrosis area. Automated quantification in a large cohort of chronic hepatitis C showed that perisinusoidal fibrosis progressively grew in early fibrosis stages but did not increase in septal or cirrhotic stages and that the portal-bridging fibrosis area appeared as a more accurate tool to assess fibrosis progression than the whole fibrosis area.

Invasive and non-invasive diagnosis of cirrhosis and portal hypertension

With advances in the management and treatment of advanced liver disease, including the use of antiviral therapy, a simple, one stage description for advanced fibrotic liver disease has become inadequate. Although refining the diagnosis of cirrhosis to reflect disease heterogeneity is essential, current diagnostic tests have not kept pace with the progression of this new paradigm. Liver biopsy and hepatic venous pressure gradient measurement are the gold standards for the estimation of hepatic fibrosis and portal hypertension (PHT), respectively, and they have diagnostic and prognostic value. However, they are invasive and, as such, cannot be used repeatedly in clinical practice. The ideal noninvasive test should be safe, easy to perform, inexpensive, reproducible as well as to give numerical and accurate results in real time. It should be predictive of long term outcomes related with fibrosis and PHT to allow prognostic stratification. Recently, many types of noninvasive alternative tests have been developed and are under investigation. In particular, imaging and ultrasound based tests, such as transient elastography, have shown promising results. Although most of these noninvasive tests effectively identify severe fibrosis and PHT, the methods available for diagnosing moderate disease status are still insufficient, and further investigation is essential to predict outcomes and individualize therapy in this field.

Assessment of liver fibrosis with elastography point quantification technique in chronic hepatitis B virus patients: a comparison with liver pathological results

BACKGROUND AND AIM

Elastography point quantification (ElastPQ) was a newly non-invasive method for the assessment of liver fibrosis by measuring liver stiffness. We aimed at evaluating the reproducibility of ElastPQ technology in the determination of liver stiffness and to investigate the value of ElastPQ in liver fibrosis staging among chronic hepatitis B patients.

METHODS

A total of 291 successive patients who underwent liver partial hepatectomy or biopsy were examined with the ElastPQ technology for the measurement of liver stiffness. Ten ElastPQ measurements were obtained in the right lobe of the liver through the seventh to the tenth intercostal space for every patient. The reproducibility of ElastPQ technology was analyzed with intraclass correlation (ICC) of reliability analysis. Comparing the median of 10 measurements of ElastPQ with liver fibrosis, necroinflammatory activity, and steatosis pathologically, as well as gender and age, potential factors affecting liver stiffness were explored by multiple linear regression analysis, and the performances of ElastPQ were evaluated with repeated measures anova and receiver operating characteristic (ROC) curve.

RESULTS

The ICC of 10 measurements of liver stiffness with ElastPQ technique was 0.798, which indicated a good reproducibility. Liver fibrosis and necroinflammatory activity were positively correlated with ElastPQ (P = 0.00, 0.01 < 0.05) while other factors had no effect on ElastPQ. There was significant difference of ElastPQ between S1 (5.60 ± 2.55 kPa) and S2 (7.44 ± 3.43 kPa) (P = 0.01 < 0.05), and S3 (8.71 ± 3.14 kPa) and S4 (10.87 ± 5.25 kPa) (P = 0.01 < 0.05). The area under the ROC curve was 0.94 (6.99 kPa, the optimal cut-off value) for ElastPQ measured with ElastPQ between S0-1 and S2-3, 0.89 (9.00 kPa) for ElastPQ between S2-3 and S4.

CONCLUSION

ElastPQ is a valid and reproducible non-invasive technology in liver stiffness measurement among chronic hepatitis B patients. The stage of liver fibrosis and the grade of necroinflammatory activity are associated with values of ElastPQ while liver fibrosis is the dominating factor affecting liver stiffness measured by ElastPQ.

Precise evaluation of liver histology by computerized morphometry shows that steatosis influences liver stiffness measured by transient elastography in chronic hepatitis C

BACKGROUND

Liver stiffness evaluation (LSE) by Fibroscan is now widely used to assess liver fibrosis in chronic hepatitis C. Liver steatosis is a common lesion in chronic hepatitis C as in other chronic liver diseases, but its influence on LSE remains unclear. We aimed to precisely determine the influence of steatosis on LSE by using quantitative and precise morphometric measurements of liver histology.

METHODS

650 patients with chronic hepatitis C, liver biopsy, and LSE were included. Liver specimens were evaluated by optical analysis (Metavir F and A, steatosis grading) and by computerized morphometry to determine the area (%, reflecting quantity) and fractal dimension (FD, reflecting architecture) of liver fibrosis and steatosis.

RESULTS

The relationships between LSE and liver histology were better described using morphometry. LSE median was independently linked to fibrosis (area or FD), steatosis (area or FD), activity (serum AST), and IQR/LSE median. Steatosis area ≥4.0 % induced a 50 % increase in LSE result in patients with fibrosis area <9 %. In patients with IQR/LSE median ≤0.30, the rate of F0/1 patients misclassified as F ≥ 2 by Fibroscan was, respectively for steatosis area <4.0 and ≥4.0 %: 12.6 vs 32.4 % (p = 0.003). Steatosis level did not influence LSE median when fibrosis area was ≥9 %, and consequently did not increase the rate of F ≤ 3 patients misclassified as cirrhotic.

CONCLUSION

A precise evaluation of liver histology by computerized morphometry shows that liver stiffness measured by Fibroscan is linked to liver fibrosis, activity, and also steatosis. High level of steatosis induces misevaluation of liver fibrosis by Fibroscan.

The diagnostic accuracy of Fibroscan for cirrhosis is influenced by liver morphometry in HCV patients with a sustained virological response

BACKGROUND & AIMS

Transient elastography (TE) is a validated non-invasive tool to evaluate hepatic fibrosis in patients with hepatitis C virus (HCV) infection. Whether TE may sense changes of liver fibrosis following therapeutic HCV eradication has never been evaluated.

METHODS

37 HCV cirrhotics with paired pre- and post-sustained virological response (SVR) liver biopsies (LB) underwent TE at the time of post-SVR LB. Liver fibrosis was staged with the METAVIR scoring system and the area of fibrosis (%) was assessed morphometrically.

RESULTS

Thirty-three patients had valid TE measurements after 61 (48-104) months from an SVR, and 20 (61%) of them had cirrhosis regression. On post-SVR LB, the median area of fibrosis was 2.3%, being significantly reduced from baseline (p<0.0001). Median TE value was 9.8 kPa being lower in regressed vs. not regressed patients (9.1 kPa vs. 12.9 kPa, p=0.01). TE was <12 kPa in 5 (38%) F4 patients and in 19 (95%) ≤F3 patients (p=0.0007). The diagnostic accuracy of TE for diagnosing F4 after treatment was 61% sensitivity, 95% specificity, 12.3 LR+, 0.4 LR-, and AUROC 0.77. A significant correlation was found between TE and both fibrosis stage (r=0.56; p=0.001) and morphometry (r=0.56, p=0.001) as well as between fibrosis stage and area of fibrosis (r=0.72, p=0001).

CONCLUSIONS

Following therapeutic eradication of HCV, the predictive power of the viremic cut-off of 12 kPa was low as a consequence of liver remodelling and fibrosis reabsorption. LB still remains the only reliable approach to stage liver fibrosis following an SVR.

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.

Determination of reliability criteria for liver stiffness evaluation by transient elastography

Liver stiffness evaluation (LSE) is usually considered as reliable when it fulfills all the following criteria: ≥10 valid measurements, ≥60% success rate, and interquartile range / median ratio (IQR/M) ≤0.30. However, such reliable LSE have never been shown to be more accurate than unreliable LSE. Thus, we aimed to evaluate the relevance of the usual definition for LSE reliability, and to improve reliability by using diagnostic accuracy as a primary outcome in a large population. 1,165 patients with chronic liver disease from 19 French centers were included. All patients had liver biopsy and LSE. 75.7% of LSE were reliable according to the usual definition. However, these reliable LSE were not significantly more accurate than unreliable LSE with, respectively: 85.8% versus 81.5% well-classified patients for the diagnosis of cirrhosis (P = 0.082). In multivariate analyses with different diagnostic targets, LSE median and IQR/M were independent predictors of fibrosis staging, with no significant influence of ≥10 valid measurements or LSE success rate. These two reliability criteria determined three LSE groups: "very reliable" (IQR/M ≤0.10), "reliable" (0.10< IQR/M ≤0.30, or IQR/M >0.30 with LSE median <7.1 kPa), and "poorly reliable" (IQR/M >0.30 with LSE median ≥7.1 kPa). The rates of well-classified patients for the diagnosis of cirrhosis were, respectively: 90.4%, 85.8%, and 69.5% (P < 10(-3) ). According to these new reliability criteria, 9.1% of LSE were poorly reliable (versus 24.3% unreliable LSE with the usual definition, P < 10(-3) ), 74.3% were reliable, and 16.6% were very reliable.

CONCLUSION

The usual definition for LSE reliability is not relevant. LSE reliability depends on IQR/M according to liver stiffness median level, defining thus three reliability categories: very reliable, reliable, and poorly reliable LSE. (HEPATOLOGY 2013).

Liver stiffness measurements in patients with different stages of nonalcoholic fatty liver disease: diagnostic performance and clinicopathological correlation

BACKGROUND

The present study evaluated performance characteristics of liver stiffness measurement (LSM) by FibroScan in patients with different stages of nonalcoholic fatty liver disease (NAFLD).

PATIENTS AND METHODS

A total of 307 subjects (120 NAFLD, 85 NAFLD related cirrhosis, and 102 healthy controls) were studied.

RESULTS

In NAFLD patients, LSM had significant correlation with fibrosis (r = 0.68, p < 0.001), and increased progressively with increasing fibrosis (p < 0.001). However, the difference between stage 1 and stage 2 fibrosis was not significant (p = 0.07). The LSM in NAFLD without fibrosis and healthy controls was similar (p = 0.37). The areas under receiver-operating characteristics (AUROC) curve of LSM for stages ≥1, ≥2, ≥3, and 4 were 0.82, 0.85, 0.94, and 0.96, respectively. The best LSM (kPa) cut-offs for fibrosis stages ≥1, ≥2, ≥3 and 4 were 6.1, 7.0, 9.0, and 11.8, respectively. The negative predictive value of LSM for excluding advanced fibrosis was 95%. For advanced fibrosis, the AUROC curve of LSM was 0.94, followed by FIB-4 (0.75), BARD score (0.68), NAFLD fibrosis score (0.66), and aspartate platelet ratio index (0.60). In multivariate analysis, LSM was the only independent predictor of advanced fibrosis (odds ratio 1.47). In patients with NAFLD cirrhosis, LSM correlated significantly with Child-Pugh score (r = 0.40, p < 0.001), serum bilirubin (r = 0.34, p = 0.02), and grades of esophageal varices (r = 0.23, p = 0.04).

CONCLUSION

LSM is a useful tool for evaluation of patients with NAFLD, and is the best among other non-invasive predictors of liver fibrosis.

Analysis of discordance between transient elastography and liver biopsy for assessing liver fibrosis in chronic hepatitis B virus infection

BACKGROUND

Transient elastography (TE) is used to assess liver fibrosis in chronic hepatitis B virus (CHBV) infection. However, factors affecting liver stiffness (LS) values and discordance between TE and liver biopsy in CHBV infection remain to be evaluated.

AIM

The aim is to define the optimal cutoff values of LS for significant fibrosis (≥F2) and cirrhosis (F4) and to study the clinical and histological variables associated with LS values and discordance between TE and liver biopsy in assessing liver fibrosis in CHBV-infected subjects.

METHODS

Patients with CHBV infection (n = 200; 159 male; age 37.6 ± 3.7 years) underwent liver biopsy concomitantly with TE. Liver biopsy was scored for activity (Ishak score), fibrosis (METAVIR score), steatosis, cholestasis, and congestion. Hepatic fibrosis percentage was estimated by morphometry.

RESULTS

Liver stiffness values were significantly correlated with histological activity index (HAI) score, F score, and fibrosis percentage. Optimal cutoff values for prediction of significant fibrosis and cirrhosis were 7.05 kPa [sensitivity 81.2 %; specificity 74 %; area under the receiver operating characteristic curve (AUROC) 0.850] and 10.85 kPa (sensitivity 87 %; specificity 85.3 %; AUROC 0.907), respectively. A total of 47 (23.5 %) [overestimation of actual fibrosis by TE, 34 (17 %); underestimation, 13 (6.5 %)] and 28 (14 %) [overestimation, 25 (12.5 %); underestimation, 3 (1.5 %)] patients showed discrepant results for diagnosis of significant fibrosis and cirrhosis, respectively. HAI and interquartile range (IQR) were the factors predictive of overestimation in cirrhosis.

CONCLUSIONS

Fibrosis and necroinflammatory activity are the main determinants of TE in CHBV infection. Overestimation of actual fibrosis stage by TE is common and is influenced by necroinflammatory activity and IQR for estimation of cirrhosis.

Reliability of liver stiffness measurement in non-alcoholic fatty liver disease: the effects of body mass index

BACKGROUND

Liver stiffness measurement (LSM) using transient elastography (TE) is used to stage fibrosis in patients with liver disease, diagnostic reliability and the factors affecting its performance in patients with non-alcoholic fatty liver disease (NAFLD) are incompletely understood.

AIM

To assess LSM.

METHODS

Consecutive NAFLD patients (n = 169), assessed by liver biopsy (Kleiner score), anthropometrical, biochemical and metabolic features, underwent LSM using TE with standard M probe.

RESULTS

Liver stiffness measurement was not reliable in 23 patients (14%) due to obesity. Among patients with a reliable TE, a LSM value >7.25 kPa was the best cut-off for predicting significant fibrosis at biopsy (AUC 0.794); however, this cut-off still failed to rule out F2-F4 fibrosis in 31% (false-negative rate) or rule in F3-F4 in 29% (false-positive rate). Similarly a LSM value >8.75 kPa was the best cut-off for severe fibrosis (F3-F4) (AUC 0.870), with a rate of false-negatives 24% and of false-positives 2%. Body mass index was the major determinant of these diagnostic errors in predicting significant and severe fibrosis both by overestimating or underestimating the stage of fibrosis.

CONCLUSIONS

In NAFLD patients, even when liver stiffness measurement is feasible, high BMI values negatively affect the diagnostic reliability. Improved performance of transient elastography could be obtained using specifically designed probes.

Reliability of transient elastography for the detection of fibrosis in non-alcoholic fatty liver disease and chronic viral hepatitis

BACKGROUND & AIMS

Transient elastography (TE) is validated in chronic hepatitis C (CHC) to evaluate hepatic fibrosis; however, limited data are available in chronic hepatitis B (CHB) and non-alcoholic fatty liver disease (NAFLD). This prospective study is aimed to assess the accuracy and the efficacy of TE for the detection of fibrosis in patients with chronic liver disease of different etiology and to evaluate the effect of steatosis on the liver stiffness measurement (LSM).

METHODS

TE was performed in 219 consecutive patients with chronic liver disease (35% CHC, 32% CHB, and 33% NAFLD) within 6 months of the liver biopsy.

RESULTS

LSM was related to the fibrosis stage in each group (CHC: p = 0.596, p < 0.001; CHB: p = 0.418, p < 0.001; NAFLD: p = 0.573, p < 0.001), but the correlation was less strong in CHB and NAFLD than in CHC patients. In CHB patients with histological cirrhosis (F4), the median stiffness value was almost two times lower than in patients with severe fibrosis (F3). In NAFLD patients with advanced fibrosis (F3) and severe steatosis (> 33%), the LSM values were lower than expected and were similar to those of patients with initial fibrosis (F1) and fat < 33%. TE underestimated the stage of fibrosis in 75% of patients with F3 and steatosis > 33%. At multiple logistic regression analysis, in CHC and CHB patients, LSM was the only predictive variable of severe fibrosis/cirrhosis (OR = 1.42, p = 0.003 and OR = 1.354, p = 0.003, respectively), while in NAFLD subjects BMI and AST (OR = 1.433, p = 0.002 and OR = 1.053, p = 0.020, respectively) but not LSM were independently related with advanced fibrosis and cirrhosis.

CONCLUSIONS

This study confirms that TE can be considered a valid support to detect fibrosis in chronic liver disease related to HCV but it should be interpreted cautiously in CHB and NAFLD patients, where host or disease-related factors may modify its accuracy.

The Diagnostic Value of Ultrasound Elastography in Patients with Hepatitis B Virus Infection: A Prospective Study

The aim of this prospective study was to investigate the diagnostic value of ultrasound elastography for evaluating liver stiffness measurement (LSM) in 74 patients with hepatitis B virus (HBV) infection, treated with telbivudine (22 with chronic HBV infection, 32 with compensated cirrhosis and 20 with decompensated cirrhosis). Each patient underwent ultrasound elastography measurements and serum liver marker assays before and after 6 months' treatment with 600 mg telbivudine, orally, once daily. In the 22 patients with chronic HBV infection, LSM values measured by ultrasound elastography decreased significantly following the treatment period compared with baseline. The LSM values were significantly higher in the 20 patients with decompensated cirrhosis than in the 32 patients with compensated cirrhosis after treatment. Significant decreases in serum hepatic fibrosis indices occurred in all patients following treatment. The correlation between fibrosis index, hyaluronic acid level and LSM was statistically significant in all patients, whereas the correlation between alanine aminotransferase and LSM was not. The findings suggest that liver stiffness in patients with HBV can be measured simply with ultrasound elastography and that it is reduced within 6 months by treatment with telbivudine. The main adverse events noted during the study period were that creatine kinase levels were increased in seven patients and that seven patients had influenza-like symptoms.