Quantification of fibrosis by collagen proportionate area predicts hepatic decompensation in hepatitis C cirrhosis

The prediction of liver decompensation using hepatic collagen deposition assessed by computer-assisted image analysis with Masson's trichrome stain

BACKGROUND & AIM

The current pathologic system classifies structural deformation caused by hepatic fibrosis semi-quantitatively, which may lead to a disagreement among pathologists. We measured hepatic fibrosis quantitatively using collagen proportionate area (CPA) in compensated cirrhotic patients and assessed its impact on predicting the development of liver decompensation.

METHOD

From January 2010 to June 2018, we assessed 101 patients who went through liver biopsy and received diagnosis as compensated cirrhosis with digital image analysis of CPA. Clinical and laboratory data were collected at the baseline and at the time of the last follow-up or progression to liver decompensation (LD).

RESULT

The mean age was 50.8 ± 10.5 years, and the most common etiology of liver disease was chronic hepatitis B (48.5%), followed by alcoholic hepatitis (18.8%). The mean CPA was 16.91 ± 9.60%. The mean CPA values were different in patients with and without LD development (21.8 ± 11.1 vs. 15.2 ± 8.5). During the median follow-up of 60.0 months, 26 out of 101 patients experienced LD. Older age (hazard ratio [HR],1.069; p = 0.015), prolonged international normalized ratio (HR, 6.449; p = 0.019) and higher CPA (HR, 1.049; p = 0.040) were independent predictors of liver decompensation on multivariate cox-regression analysis. When patients were divided according to the optimal CPA threshold (26.8%), higher CPA predicted LD better than lower CPA. (Log-rank test: p < 0.001).

CONCLUSION

CPA could be a useful quantitative prognostic value for patients with compensated cirrhosis.

Biased Quantification of Rat Liver Fibrosis-Meta-Analysis with Practical Recommendations and Clinical Implications

For liver fibrosis assessment, the liver biopsy is usually stained with Masson's trichrome (MT) or picrosirius red (PSR) to quantify liver connective tissue (LCT) for fibrosis scoring. However, several concerns of such semiquantitative assessments have been raised, and when searching for data on the amount of LCT in healthy rats, the results vastly differ. Regarding the ongoing reproducibility crisis in science, it is necessary to inspect the results and methods, and to design an unbiased and reproducible method of LCT assessment. We searched the Medline database using search terms related to liver fibrosis, LCT and collagen, rat strains, and staining methods. Our search identified 74 eligible rat groups in 57 studies. We found up to 170-fold differences in the amount of LCT among healthy Wistar and Sprague-Dawley rats, with significant differences even within individual studies. Biased sampling and quantification probably caused the observed differences. In addition, we also found incorrect handling of liver fibrosis scoring. Assessment of LCT using stereological sampling methods (such as systematic uniform sampling) would provide us with unbiased data. Such data could eventually be used not only for the objective assessment of liver fibrosis but also for validation of noninvasive methods of the assessment of early stages of liver fibrosis.

The compound annual growth rate of the fibrosis-4 index in chronic hepatitis B patients

Chronic hepatitis B (CHB) patients with low disease activity are at risk of liver fibrosis. The age-adjusted fibrosis-4 index (FIB4-AA), developed in our previous publication, and was implemented to evaluate the tendency of liver fibrosis in these patients. We aimed to investigate the rate of liver fibrosis in CHB patients with low disease activity. Resuming our previous study, the FIB-4 changes of 244 antiviral treatment-naïve CHB patients, with a total of 1243.48 person-years, were reviewed. Among the cohort, patients were categorized as FIB4-AA positive or negative according to the results of their last FIB4-AA minus their initial FIB-4 during at least 18 months of observation time. The compound annual growth rate (CAGR) of FIB-4 was calculated for the FIB4-AA positive and negative groups. The assumed healthy controls had an FIB-4 CAGR calculated to be 2.34% for both men and women, while the FIB-4 CAGR of the whole study cohort was 2.84% ± 6.01%. FIB4-AA positive effectively identifies CHB patients with higher mean FIB-4 CAGR (7.11% ± 3.88% vs. -2.36% ± 3.52%, p < 0.0001). Overweight CHB patients had 10 times smaller mean FIB-4 CAGR than lean ones (0.38% ± 10.35% vs. 3.83% ± 8.88%, p = 0.009). An increase in FIB4-AA over at least 18 months in CHB patients with relatively low disease activity meant they were at greater risk of liver fibrosis, and these patients had a mean FIB-4 CAGR of 7.11%. The FIB-4 CAGR was compatible with the findings of previous studies on the collagen proportionate area in viral hepatitis patients.

Collagen proportionate area predicts long-term mortality in patients with alcoholic hepatitis

BACKGROUND AND AIMS

There are several short-term prognostic scores for alcoholic hepatitis (AH) that combine demographical and biochemical parameters. The extent of liver fibrosis may also be relevant to the prognosis of AH with potential added value. We evaluated collagen proportionate area (CPA) as a predictor of short and long-term mortality in AH.

METHODS

We retrospectively included patients with biopsy-verified AH. Clinical, laboratory and outcome data were collected. CPA and five AH scores were calculated: Maddrey's DF, MELD, GAHS, ABIC, and the Lille Model. Predictors of short and long-term all-cause mortality were assessed using Cox regression analysis.

RESULTS

We included 140 patients with AH. In total, 67 (48%) patients died after a median follow-up of 66 (IQR 102) months, with 17 (12%) dying within the first 90-days. CPA was not a predictor of 90-days mortality and had no additional value to the prognostic AH scores on short-term mortality. However, CPA predicted long-term mortality independently of prognostic AH scores. Importantly, CPA and abstinence from alcohol were independent predictors of long-term mortality in patients alive 90 days after the biopsy.

CONCLUSION

CPA predicts long-term mortality in patients with AH independently of abstinence from alcohol but has no prognostic value on short-term mortality.

Collagen proportionate area correlates with histological stage and predicts clinical events in primary sclerosing cholangitis

BACKGROUND & AIMS

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease in need of accurate biomarkers for stratification and as surrogates for clinical endpoints in trials. Quantitative liver fibrosis assessment by collagen proportionate area (CPA) measurement has been demonstrated to correlate with clinical outcomes in chronic hepatitis C, alcohol-related and non-alcoholic fatty liver disease. We aimed to investigate the ability of CPA to quantify liver fibrosis and predict clinical events in PSC.

METHODS

Biopsies from 101 PSC patients from two European centres were retrospectively assessed by two expert pathologists in tandem, using grading (Ishak and Nakanuma) and staging (Ishak, Nakanuma, Ludwig) systems recently validated to predict clinical events in PSC. CPA was determined by image analysis of picro-Sirius red-stained sections following a standard protocol. We assessed the correlations between CPA, staging and grading and their associations with three outcomes: (1) time to PSC-related death, liver transplant or primary liver cancer; (2) liver transplant-free survival; (3) occurrence of cirrhosis-related clinical manifestations.

RESULTS

CPA correlated strongly with histological stage determined by each scoring system (P < .001) and was significantly associated with the three endpoints. Median time to endpoint-1, endpoint-2 and endpoint-3 was shorter in patients with higher CPA, on Kaplan-Meier analyses (P = .011, P = .034 and P = .001, respectively).

CONCLUSION

Quantitative fibrosis assessment by CPA has utility in PSC. It correlates with established histological staging systems and predicts clinical events. CPA may be a useful tool for staging fibrosis and for risk stratification in PSC and should be evaluated further within prospective clinical trials.

High-Throughput, Machine Learning-Based Quantification of Steatosis, Inflammation, Ballooning, and Fibrosis in Biopsies From Patients With Nonalcoholic Fatty Liver Disease

BACKGROUND & AIMS

Liver biopsy is the reference standard for staging and grading nonalcoholic fatty liver disease (NAFLD), but histologic scoring systems are semiquantitative with marked interobserver and intraobserver variation. We used machine learning to develop fully automated software for quantification of steatosis, inflammation, ballooning, and fibrosis in biopsy specimens from patients with NAFLD and validated the technology in a separate group of patients.

METHODS

We collected data from 246 consecutive patients with biopsy-proven NAFLD and followed up in London from January 2010 through December 2016. Biopsy specimens from the first 100 patients were used to derive the algorithm and biopsy specimens from the following 146 were used to validate it. Biopsy specimens were scored independently by pathologists using the Nonalcoholic Steatohepatitis Clinical Research Network criteria and digitalized. Areas of steatosis, inflammation, ballooning, and fibrosis were annotated on biopsy specimens by 2 hepatobiliary histopathologists to facilitate machine learning. Images of biopsies from the derivation and validation sets then were analyzed by the algorithm to compute percentages of fat, inflammation, ballooning, and fibrosis, as well as the collagen proportionate area, and compared with findings from pathologists' manual annotations and conventional scoring systems.

RESULTS

In the derivation group, results from manual annotation and the software had an interclass correlation coefficient (ICC) of 0.97 for steatosis (95% CI, 0.95-0.99; P < .001); ICC of 0.96 for inflammation (95% CI, 0.9-0.98; P < .001); ICC of 0.94 for ballooning (95% CI, 0.87-0.98; P < .001); and ICC of 0.92 for fibrosis (95% CI, 0.88-0.96; P = .001). Percentages of fat, inflammation, ballooning, and the collagen proportionate area from the derivation group were confirmed in the validation cohort. The software identified histologic features of NAFLD with levels of interobserver and intraobserver agreement ranging from 0.95 to 0.99; this value was higher than that of semiquantitative scoring systems, which ranged from 0.58 to 0.88. In a subgroup of paired liver biopsy specimens, quantitative analysis was more sensitive in detecting differences compared with the nonalcoholic steatohepatitis Clinical Research Network scoring system.

CONCLUSIONS

We used machine learning to develop software to rapidly and objectively analyze liver biopsy specimens for histologic features of NAFLD. The results from the software correlate with those from histopathologists, with high levels of interobserver and intraobserver agreement. Findings were validated in a separate group of patients. This tool might be used for objective assessment of response to therapy for NAFLD in practice and clinical trials.

Correlation analysis of collagen proportionate area in Budd-Chiari syndrome: A preliminary clinicopathological study

BACKGROUND

Collagen proportionate area (CPA) is an important index for assessing the severity of liver fibrosis. Budd-Chiari syndrome can frequently progress to liver fibrosis and cirrhosis. CPA might play an important role in the pathological progress of Budd-Chiari syndrome.

AIM

To explore the role of CPA in predicting the outcomes of patients with Budd-Chiari syndrome.

METHODS

Nine patients with Budd-Chiari syndrome undergoing transjugular intrahepatic portosystemic shunt (TIPS) were included. The median CPA level and correlation of CPA and prognosis of TIPS were determined.

RESULTS

Median CPA was 23.07% (range: 0%-40.20%). Pearson’s χ² test demonstrated a significant correlation of CPA with history of gastrointestinal bleeding (Pearson’s coefficient: 0.832, P = 0.005), alanine aminotransferase (Pearson’s coefficient: -0.694, P = 0.038), and prothrombin time (Pearson’s coefficient: 0.68, P = 0.044). Although CPA was not significantly correlated with shunt dysfunction or hepatic encephalopathy after TIPS, the absolute CPA was relatively larger in patients who developed shunt dysfunction or hepatic encephalopathy after TIPS.

CONCLUSION

This preliminary clinicopathological study found a marginal effect of CPA on the outcomes of Budd-Chiari syndrome patients treated with TIPS.

Diagnosis and staging of fibrosis in patients with chronic hepatitis C: comparison and critical overview of current strategies

In the past years, what has always been considered undisputed true in liver fibrosis staging has been challenged. Diagnostic performance of histological evaluation has proven to be significantly influenced by sample- and observer-related variabilities. Differentiation between lower levels of fibrosis remains difficult for many, if not all, test modalities, including liver biopsy but, perhaps, such a distinction is not indispensable in light of current therapeutic approaches. Biomarkers and elastography offer, nonetheless, high predictive values for advanced fibrosis and cirrhosis and correlate well with liver-related outcomes. Necroinflammation, steatosis, and hemodynamic changes may significantly interfere with elastography-based techniques, and longitudinal follow-up strategies must be tailored in light of these findings. Knowledge of different test modalities and diagnostic performance indicators can allow for better clinical decision-making and resource allocation.

Elastogram quality assessment score in vibration-controlled transient elastography: Diagnostic performance compared to digital morphometric analysis of liver biopsy in chronic hepatitis C

Vibration-controlled transient elastography (VCTE) is widely used for noninvasive fibrosis staging in chronic hepatitis C. However, internal validation is based solely on variability and success rate and lacks reproducible quality indicators. We analysed the graphic representation of shear wave propagation in comparison with morphometric results of liver biopsy, eliminating observer variability bias. Individual elastograms were classified according to two morphologic criteria: extension of wave propagation (length of the graphic representation) and shear wave dispersal (level of parallelism displayed in the elastogram). Then, a score based on these criteria stratified the elastogram in classes I through III (highest to lowest technical quality). Liver stiffness results of each measurement were compared with collagen contents in liver biopsy by morphometric analysis. A total of 3243 elastograms were studied (316 patients). Digital morphometry in liver biopsy showed significant fibrosis in 66% of samples and advanced fibrosis in 31%. Elastogram quality analysis resulted in 1438 class I measurements (44%), 1070 class II (34%) and 735 class III. Area under the receiver operating curve (AUROC) for severe fibrosis according to class (I, II and III) was 0.941, 0.887 and 0.766, respectively. For advanced fibrosis, AUROCs were 0.977, 0.883 and 0.781, respectively. Spearman's correlation testing for all classes and levels of fibrosis demonstrated significant independent association (r²  = -.95, P < .01). Our study is the first to propose measurable quality criteria for VTCE and to validate them against objective assessment of liver biopsy through digital morphometric imaging analysis. We concluded that VCTE performance is significantly influenced by quality assessment of individual measurements. Considering these criteria in clinical practice may improve accuracy.

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.

Development of an in vitro model to test antifibrotic drugs on primary human liver myofibroblasts

We have developed a culture model to assess antifibrotic drugs using normal human liver myofibroblasts (HLMFs) obtained from 31 subjects. Activation was evaluated in terms of α-smooth muscle actin (α-SMA) and collagen 1 (Coll1) expression using RT-PCR, and proliferation as the uptake of 5-ethynil-2'-deoxyuridine. Under analysis of variance, between-subject differences accounted for 70% of all variability and inter-experiment differences for 30%. The sensitivity of the model was determined by quantifying the effects in terms of relative expression, which were 0.74±0.03 for cyclosporine A (CsA) and 2.4±0.10 for transforming growth factor-beta (TGF-β) (P<0.0001 vs no treatment) for α-SMA expression. Inter-subject variations in α-SMA and Coll1 expression enabled the classification of subjects as potentially low or high fibrosers. Finally, we observed that pirfenidone (which has beneficial effects in vivo) significantly reduced the expressions of α-SMA and Coll1, whereas the angiotensin-converting enzyme inhibitor losartan (which has no effect in vivo) had no significant effect. Our model may thus detect the antifibrotic properties of drugs. Antifibrotic drugs with promising clinical relevance could possibly be selected using a bank of HLMFs from high fibrosers.

Ultrasound elastographic techniques in focal liver lesions

Elastographic techniques are new ultrasound-based imaging techniques developed to estimate tissue deformability/stiffness. Several ultrasound elastographic approaches have been developed, such as static elastography, transient elastography and acoustic radiation force imaging methods, which include point shear wave and shear wave imaging elastography. The application of these methods in clinical practice aims at estimating the mechanical tissues properties. One of the main settings for the application of these tools has been liver stiffness assessment in chronic liver disease, which has been studied mainly using transient elastography. Another field of application for these techniques is the assessment of focal lesions, detected by ultrasound in organs such as pancreas, prostate, breast, thyroid, lymph nodes. Considering the frequency and importance of the detection of focal liver lesions through routine ultrasound, some studies have also aimed to assess the role that elestography can play in studying the stiffness of different types of liver lesions, in order to predict their nature and thus offer valuable non-invasive methods for the diagnosis of liver masses.

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.