Diagnostic performance of controlled attenuation parameter for predicting steatosis grade in chronic hepatitis B

Improved Ultrasound Attenuation Measurement Method for the Non-invasive Evaluation of Hepatic Steatosis Using FibroScan

Controlled attenuation parameter (CAP) is a measurement of ultrasound attenuation used to assess liver steatosis non-invasively. However, the standard method has some limitations. This study assessed the performance of a new CAP method by ex vivo and in vivo assessments. The major difference with the new method is that it uses ultrasound data continuously acquired during the imaging phase of the FibroScan examination. Seven reference tissue-mimicking phantoms were used to test the performance. In vivo performance was assessed in two cohorts (in total 195 patients) of patients using magnetic resonance imaging proton density fat fraction (MRI-PDFF) as a reference. The precision of CAP was improved by more than 50% on tissue-mimicking phantoms and 22%-41% in the in vivo cohort studies. The agreement between both methods was excellent, and the correlation between CAP and MRI-PDFF improved in both studies (0.71 to 0.74; 0.70 to 0.76). Using MRI-PDFF as a reference, the diagnostic performance of the new method was at least equal or superior (area under the receiver operating curve 0.889-0.900, 0.835-0.873). This study suggests that the new continuous CAP method can significantly improve the precision of CAP measurements ex vivo and in vivo.

Noninvasive Estimation of Hepatic Steatosis by Controlled Attenuation Parameter in Living Donor Liver Transplant

OBJECTIVES

Estimation of liver fat among living donor candidates is necessary before living donor liver transplant. This study aimed to investigate the usefulness of the controlled attenuation parameter compared with liver biopsy for pretransplant estimation of hepatic steatosis in living liver donors.

MATERIALS AND METHODS

In this retrospective study, we included all individuals who underwent transient elastography with controlled attenuation parameter and ultrasonography-guided liver biopsy as a part of donor evaluations before living donor liver transplant. Clinical and laboratory data of living donor candidates were reviewed and collected.

RESULTS

Of 49 donor candidates included in this study, 21 (42.9%) had different degrees of hepatic macrosteatosis. Of the 21 donor candidates who had hepatic steatosis in liver biopsy, 13 individuals were diagnosed to have steatosis in transient elastography. Of the 28 donor candidates without hepatic steatosis in liver biopsy, 26 individuals showed no steatosis in transient elastography (odds ratio: 21.12; 95% CI, 3.91- 114.08; P < .001). Controlled attenuation parameter was useful in discriminating presence (P = .001) and grade of hepatic steatosis (P = .009) compared with liver biopsy with good sensitivity and specificity.

CONCLUSIONS

The controlled attenuation parameter is a noninvasive method for detection of hepatic steatosis in living donor candidates and can be used as an adjunct to liver biopsy for screening of living donor candidates before liver transplant.

Liver Stiffness by Transient Elastography to Detect Porto-Sinusoidal Vascular Liver Disease With Portal Hypertension

BACKGROUND AND AIMS

Porto-sinusoidal vascular liver disease (PSVD) is a rare cause of portal hypertension. PSVD is still often misdiagnosed as cirrhosis, emphasizing the need to improve PSVD diagnosis strategies. Data on liver stiffness measurement using transient elastography (TE-LSM) in PSVD are limited. The aim of this study was to evaluate the accuracy of TE-LSM to discriminate PSVD from cirrhosis in patients with signs of portal hypertension.

APPROACH AND RESULTS

Retrospective multicenter study comparing TE-LSM in patients with PSVD, according to Vascular Liver Disease Interest Group criteria, with patients with compensated biopsy-proven cirrhosis associated with alcohol (n = 117), HCV infection (n = 110), or NAFLD (n = 46). All patients had at least one sign of portal hypertension among gastroesophageal varices, splenomegaly, portosystemic collaterals, history of ascites, or platelet count < 150 × 10⁹ /L. The 77 patients with PSVD included in the test cohort had lower median TE-LSM (7.9 kPa) than the patients with alcohol-associated, HCV-related, and NAFLD-related cirrhosis (33.8, 18.2, and 33.6 kPa, respectively; P < 0.001). When compared with cirrhosis, a cutoff value of 10 kPa had a specificity of 97% for the diagnosis of PSVD with a 85% positive predictive value. A cutoff value of 20 kPa had a sensitivity of 94% for ruling out PSVD with a 97% negative predictive value. Of the patients, 94% were well-classified. Even better results were obtained in a validation cohort including 78 patients with PSVD.

CONCLUSIONS

This study including a total of 155 patients with PSVD and 273 patients with cirrhosis demonstrates that TE-LSM < 10 kPa strongly suggests PSVD in patients with signs of portal hypertension. Conversely, when TE-LSM is >20 kPa, PSVD is highly unlikely.

The performance of M and XL probes of FibroScan for the diagnosis of steatosis and fibrosis on a Brazilian nonalcoholic fatty liver disease cohort

OBJECTIVES

Recently, controlled attenuation parameter (CAP) was incorporated for XL probe. However, its performance through M and XL probes has been scarcely evaluated in nonalcoholic fatty liver disease (NAFLD). The performance of probes regarding transient elastography by Fibroscan is still under debate.

AIM

Compare the performance of CAP and transient elastography in NAFLD patients obtained through XL with M probes using histological analysis as gold standard.

METHODS

NAFLD patients underwent liver biopsy and FibroScan/CAP with M and XL probes the same day. C-statistic evaluated CAP performance in the identification of moderate/severe (≥33%) and severe (≥66%) steatosis by both probes and transient elastography performance for identification of significant fibrosis (≥F2).

RESULTS

Eighty-one patients (74% female; age 54.2 ± 9.9 years; BMI 32.8 ± 5.2/ BMI ≥ 25 92.6%; 96% metabolic syndrome; 60% diabetes mellitus) were included. Mean CAP with M and XL probes was 314 ± 39 and 325 ± 47 dB/m, respectively. The areas under receiver operating characteristic curves (AUROCs) of the M and XL probes for steatosis detection ≥33% were 0.75 (0.64-0.84) and 0.76 (0.65-0.84) (P = 0.95) and for steatosis ≥66% 0.83 (0.73-0.90) and 0.82 (0.71-0.89) (P = 0.73), respectively, with similar performances for both degrees of steatosis. Regarding transient elastography, AUROCs of M and XL probes for ≥F2 were 0.82 (0.71-0.93) and 0.80 (0.69-0.92) (P = 0.66).

CONCLUSION

Performance of M and XL probes is similar for the diagnosis of moderate and severe steatosis and significant fibrosis even on a overweight population with NAFLD.

Noninvasive and Convenient Screening of Metabolic Syndrome Using the Controlled Attenuation Parameter Technology: An Evaluation Based on Self-Paid Health Examination Participants

Background: There is a medical need for an easy, fast, and non-invasive method for metabolic syndrome (MetS) screening. This study aimed to assess the ability of FibroScan to detect MetS, in participants who underwent a self-paid health examination. Methods: A retrospective cohort study was conducted on all adults who underwent a self-paid health examination comprising of an abdominal transient elastography inspection using FibroScan 502 Touch from March 2015 to February 2019. FibroScan can assess the level of liver fibrosis by using a liver stiffness score, and the level of liver steatosis by using the controlled attenuation parameter (CAP) score. The logistic regression analysis and receiver operating characteristic curve were applied to select significant predictors and assess their predictability. A final model that included all significant predictors that are found by univariate analysis, and a convenient model that excluded all invasive parameters were created. Results: Of 1983 participants, 13.6% had a physical status that fulfilled MetS criteria. The results showed that the CAP score solely could achieve an area under the curve (AUC) of 0.79 (0.76–0.82) in predicting MetS, and the AUC can be improved to 0.88 (0.85–0.90) in the final model. An AUC of 0.85 (0.83–0.88) in predicting MetS was obtained in the convenient model, which includes only 4 parameters (CAP score, gender, age, and BMI). A panel of predictability indices (the ranges of sensitivity, specificity, positive and negative likelihood ratio: 0.78–0.89, 0.66–0.82, 2.64–4.47, and 0.17–0.26) concerning gender- and BMI-specific CAP cut-off values (range: 191.65–564.95) were presented for practical reference. Conclusions: Two prediction systems were proposed for identifying individuals with a physical status that fulfilled the MetS criteria, and a panel of predictability indices was presented for practical reference. Both systems had moderate predictive performance. The findings suggested that FibroScan evaluation is appropriate as a first-line MetS screening; however, the variation in prediction performance of such systems among groups with varying metabolic derangements warrants further studies in the future.

New diagnostic technique to evaluate hepatic steatosis using the attenuation coefficient on ultrasound B mode

Purpose

We have developed a diagnostic technique to evaluate hepatic steatosis using the attenuation coefficient (ATT) in ultrasound B mode imaging. A controlled attenuation parameter (CAP) by vibration-controlled transient elastography (VCTE) has also been used to evaluate hepatic steatosis. As that method uses ultrasound A mode, visualizing the liver in real time is difficult. We designed this clinical study to evaluate the diagnostic advantage of our technique using ATT compared to CAP.

Materials and methods

The study group included 94 patients with chronic liver disease who had undergone both ATT and CAP assessment at the time of liver biopsy. The M-probe and XL-probe were used for CAP measurement. Data for ATT and CAP were compared as a function of the steatosis grade.

Results

The area under the receiver operating characteristic curve (AUC-ROCs) for ATT and PAC as a function of the steatosis grade were as follows: grade 1, 0.74 and 0.81; grade 2, 0.80 and 0.85; and grade 3, 0.96 and 0.98, respectively.

Conclusion

The accuracy of steatosis grade diagnosis using ATT was the same as that using CAP, with no significant differences and with the added advantage of B mode ultrasound being more convenient and rapid, compared to A mode ultrasound, particularly for patients with subcutaneous fat thickness ≥2 cm.

Controlled attenuation parameter in NAFLD identifies risk of suboptimal glycaemic and metabolic control

AIMS

To examine the relationship between steatosis quantified by controlled attenuation parameter (CAP) values and glycaemic/metabolic control.

METHODS

230 patients, recruited from an Endocrine clinic or primary care underwent routine Hepatology assessment, with liver stiffness measurements and simultaneous CAP. Multivariable logistic regression was performed to identify potential predictors of Metabolic Syndrome (MetS), HbA1c ≥ 7%, use of insulin, hypertriglyceridaemia and CAP ≥ 300 dB/m.

RESULTS

Patients were 56.7 ± 12.3 years of age with a high prevalence of MetS (83.5%), T2DM (81.3%), and BMI ≥ 40 kg/m² (18%). Median CAP score was 344 dB/m, ranging from 128 to 400 dB/m. BMI (aOR 1.140 95% CI 1.068-1.216), requirement for insulin (aOR 2.599 95% CI 1.212-5.575), and serum ALT (aOR 1.018 95% CI 1.004-1.033) were independently associated with CAP ≥ 300 dB/m. Patients with CAP interquartile range < 40 (68%) had a higher median serum ALT level (p = 0.029), greater prevalence of BMI ≥ 40 kg/m² (p = 0.020) and higher median CAP score (p < 0.001). Patients with higher CAP scores were more likely to have MetS (aOR 1.011 95% CI 1.003-1.019), HBA1c ≥ 7 (aOR 1.010 95% CI 1.003-1.016), requirement for insulin (aOR 1.007 95% CI 1.002-1.013) and hypertriglyceridemia (aOR 1.007 95% CI 1.002-1.013).

CONCLUSIONS

Our data demonstrate that an elevated CAP reflects suboptimal metabolic control. In diabetic patients with NAFLD, CAP may be a useful point-of-care test to identify patients at risk of poorly controlled metabolic comorbidities or advanced diabetes.

EInterferon α combined with oxymatrine injection for treatment of chronic viral hepatitis B: Efficacy and effect on hepatic fibrosis and immune function

AIM

To evaluate the efficacy of interferon α (IFN-α) combined with oxymatrine injection in the treatment of chronic viral hepatitis B and its effect on hepatic fibrosis and immune function.

METHODS

Ninety-six patients with chronic hepatitis B treated at the Zhuji Central Hospital from March 2015 to June 2017 were randomly divided into either an experimental group or a control group, with 48 cases in each group. Patients in the control group were treated with IFN-α alone, while patients in the experimental group were given IFN-α combined with oxymatrine injection. After 6 mo of continuous treatment, liver function, liver fibrosis, cellular immunity, and the incidence of adverse reactions were compared between the two groups.

RESULTS

After treatment, the negative rate of HBV DNA was 83.33% in the experimental group, which was significantly higher than that of the control group (47.92%, P < 0.05). There was no significant difference in the levels of aspartate transaminase (AST), alanine transaminase (ALT), laminin (LN), hyaluronic acid (HA), or procollagen Ⅲ (PCⅢ) between the two groups before treatment (P > 0.05). After treatment, the levels of AST, ALT, LN, HA, and PCⅢ significantly decreased in both groups (P < 0.05), and the decrease in the experimental group was significantly greater than that in the control group (P < 0.05). There was no significant difference in the levels of NK cells, CD4⁺ T cells, or CD8⁺ T cells between the two groups before treatment (P > 0.05). After treatment, the levels of NK cells and CD4⁺ T cells in both groups were increased, and the level of CD8⁺ T cells in the experimental group was significantly decreased (P < 0.05), but there was no significant change in the level of CD8⁺ in the control group (P > 0.05). After treatment, the levels of NK cells, CD4⁺ T cells, and CD8⁺ T cells in the experimental group were significantly better than those in the control group (P < 0.05). The incidence of adverse reactions was 10.42% in the experimental group and 8.33% in the control group, there was no significant difference between the two groups (P > 0.05).

CONCLUSION

IFN-α combined with oxymatrine has good efficacy in the treatment of chronic hepatitis B patients and can significantly improve liver function, fibrosis, and cellular immune function.

Individual patient data meta-analysis of controlled attenuation parameter (CAP) technology for assessing steatosis

BACKGROUND & AIMS

The prevalence of fatty liver underscores the need for non-invasive characterization of steatosis, such as the ultrasound based controlled attenuation parameter (CAP). Despite good diagnostic accuracy, clinical use of CAP is limited due to uncertainty regarding optimal cut-offs and the influence of covariates. We therefore conducted an individual patient data meta-analysis.

METHODS

A review of the literature identified studies containing histology verified CAP data (M probe, vibration controlled transient elastography with FibroScan®) for grading of steatosis (S0-S3). Receiver operating characteristic analysis after correcting for center effects was used as well as mixed models to test the impact of covariates on CAP. The primary outcome was establishing CAP cut-offs for distinguishing steatosis grades.

RESULTS

Data from 19/21 eligible papers were provided, comprising 3830/3968 (97%) of patients. Considering data overlap and exclusion criteria, 2735 patients were included in the final analysis (37% hepatitis B, 36% hepatitis C, 20% NAFLD/NASH, 7% other). Steatosis distribution was 51%/27%/16%/6% for S0/S1/S2/S3. CAP values in dB/m (95% CI) were influenced by several covariates with an estimated shift of 10 (4.5-17) for NAFLD/NASH patients, 10 (3.5-16) for diabetics and 4.4 (3.8-5.0) per BMI unit. Areas under the curves were 0.823 (0.809-0.837) and 0.865 (0.850-0.880) respectively. Optimal cut-offs were 248 (237-261) and 268 (257-284) for those above S0 and S1 respectively.

CONCLUSIONS

CAP provides a standardized non-invasive measure of hepatic steatosis. Prevalence, etiology, diabetes, and BMI deserve consideration when interpreting CAP. Longitudinal data are needed to demonstrate how CAP relates to clinical outcomes.

LAY SUMMARY

There is an increase in fatty liver for patients with chronic liver disease, linked to the epidemic of the obesity. Invasive liver biopsies are considered the best means of diagnosing fatty liver. The ultrasound based controlled attenuation parameter (CAP) can be used instead, but factors such as the underlying disease, BMI and diabetes must be taken into account. Registration: Prospero CRD42015027238.

Diagnostic Accuracy of Controlled Attenuation Parameter for Detecting Hepatic Steatosis in Patients with Chronic Liver Disease

Introduction

Controlled attenuation parameter (CAP), measured by transient elastography, has been suggested as a noninvasive method for the detection and quantification of steatosis. We aimed to assess the accuracy of CAP to detect steatosis in patients with chronic liver disease (CLD) compared with liver histology and to evaluate factors that correlate with the CAP value.

Methods

Patients with CLD who underwent liver biopsy and simultaneous CAP determination were consecutively enrolled. CAP was measured using the M probe of FibroScan® (Echosens, Paris, France). Histologically, steatosis was categorized as absent (S0: <5%), mild (S1: 5-33%), moderate (S2: 34-66%) and severe (S3: >66% of all hepatocytes).

Results

We analyzed 159 patients with CLD (61% men, mean age 47.9 ± 12.9 years). We found a positive correlation between CAP and steatosis in histology (r_s = 0.869, p < 0.001), arterial hypertension (r_s = 0.222, p = 0.005), type 2 diabetes mellitus (r_s = 0.279, p < 0.001), body mass index (BMI; r_s = 0.533, p < 0.001), total cholesterol (r_s = 0.442, p < 0.001), triglycerides (r_s = 0.272, p = 0.001), and non-alcoholic fatty liver disease (NAFLD; r_s = 0.588, p < 0.001). In the multivariate analysis, BMI >25 (odds ratio [OR] 48.4, 95% confidence interval [CI] 23.78-72.95, p < 0.001), serum total cholesterol (OR 3.803, 95% CI 2.203-13.889, p = 0.008), and NAFLD etiology (OR 40.8, 95% CI 15.01-66.66, p = 0.002) were independently associated with higher CAP values. We did not find any significant correlation between CAP and the grade of necroinflammatory activity (r_s = 0.063, p = 0.808) or fibrosis (r_s = 0.071, p = 0.713) in histology and with alanine aminotransferase (r_s = 0.190, p = 0.356) or aspartate aminotransferase (r_s = 0.117, p = 0.142). Optimal CAP cutoff values for detecting steatosis ≥S1, ≥S2, and ≥S3 were 206.5, 232.5, and 282.5 dB/m, respectively. CAP performance was 0.822, 0.956, and 0.976 for diagnosing steatosis ≥S1, ≥S2, and ≥S3, respectively.

Conclusions

CAP had an excellent diagnostic accuracy for the detection of steatosis in diverse CLD patients. A CAP value cutoff of <282.5 dB/m excludes severe steatosis ≥S3 with an accuracy of 98%.

Non-invasive diagnosis of hepatic steatosis

Non-invasive diagnosis and quantification of hepatic steatosis rely on two different but complementary approaches: biomarkers or imaging techniques, either ultrasound-based such as liver ultrasonography and controlled attenuation parameter (CAP), or computed tomography (CT) and magnetic resonance imaging (MRI). Scores for the detection of steatosis have not gained much popularity in clinical practice so far. CAP, using the M probe, is the most promising technique but needs to be implemented with the XL probe and compared to ultrasound that, despite its limitations, remains the most widely used method. CT, owing to its low sensitivity and the fact that it involves a potential radiation hazard, is inappropriate. Finally, proton density fat fraction measurement by MRI is currently the most accurate and sensitive imaging method, simpler and more practical than magnetic resonance spectroscopy, but restricted, up to now, just to research and clinical trials.

Factors associated with significant liver steatosis and fibrosis as assessed by transient elastography in patients with one or more components of the metabolic syndrome

BACKGROUND/AIMS

We examined the relationship between controlled attenuation parameter (CAP) and liver stiffness measurements (LSM), as assessed by transient elastography (TE), and different clinical and biochemical parameters in patients with one or more components of the metabolic syndrome (MetS). The hypothesis of the study was that LSM and CAP values correlate with the number of MetS components.

METHODS

In this cross-sectional study a total of 648 consecutive patients were recruited during the years 2013-2015. Significant liver steatosis was defined as a CAP value≥238dB/m, whereas significant fibrosis was defined as an LSM value>7.0 kPa.

RESULTS

The prevalences of patients with CAP≥238dB/m and LSM>7.0 kPa were 88.3% and 16.5%, respectively. Patients with CAP≥238dB/m (n=572) had a markedly higher prevalence of the MetS and all its individual components, as well as higher levels of serum liver enzymes and uric acid compared with those with normal CAP. Moreover, CAP measurements increased progressively with the number of MetS components. Similarly, among patients with CAP≥238dB/m, those with LSM>7.0 kPa (n=103) had higher serum liver enzymes and a greater prevalence of the MetS and its individual components than those with LSM≤7.0 kPa. In multivariable regression analysis the factors independently associated with elevated CAP were the presence of the MetS (or its individual components), insulin resistance (defined by HOMA-IR score), increased serum uric acid and LSM>7 kPa. Similarly, the MetS (or its individual components), insulin resistance and increased serum uric acid levels were also independently associated with LSM>7.0 kPa.

CONCLUSIONS

Patients with one or more MetS components have a high prevalence of NAFLD and advanced liver fibrosis. LSM and CAP correlate with the number of MetS components.