Acoustic Radiation Force Impulse (ARFI) and Transient Elastography (TE) for evaluation of liver fibrosis in HIV-HCV co-infected patients

Extracellular vesicle-mediated approaches for the diagnosis and therapy of MASLD: current advances and future prospective

Metabolic dysfunction-associated steatotic liver disease (MASLD) is an asymptomatic, multifaceted condition often associated with various risk factors, including fatigue, obesity, insulin resistance, metabolic syndrome, and sleep apnea. The increasing burden of MASLD underscores the critical need for early diagnosis and effective therapies. Owing to the lack of efficient therapies for MASLD, early diagnosis is crucial. Consequently, noninvasive biomarkers and imaging techniques are essential for analyzing disease risk and play a pivotal role in the global diagnostic process. The use of extracellular vesicles has emerged as promising for early diagnosis and therapy of various liver ailments. Herein, a comprehensive summary of the current diagnostic modalities for MASLD is presented, highlighting their advantages and limitations while exploring the potential of extracellular vesicles (EVs) as innovative diagnostic and therapeutic tools for MASLD. With this aim, this review emphasizes an in-depth understanding of the origin of EVs and the pathophysiological alterations of these ectosomes and exosomes in various liver diseases. This review also explores the therapeutic potential of EVs as key components in the future management of liver disease. The dual role of EVs as biomarkers and their therapeutic utility in MASLD essentially highlights their clinical integration to improve MASLD diagnosis and treatment. While EV-based therapies are still in their early stages of development and require substantial research to increase their therapeutic value before they can be used clinically, the diagnostic application of EVs has been extensively explored. Moving forward, developing diagnostic devices leveraging EVs will be crucial in advancing MASLD diagnosis. Thus, the literature summarized provides suitable grounds for clinicians and researchers to explore EVs for devising diagnostic and treatment strategies for MASLD.

Evaluating M2BPGi as a Marker for Liver Fibrosis in Patients with Chronic Hepatitis B

BACKGROUND

The accurate evaluation of liver fibrosis is crucial for the treatment and follow up of chronic hepatitis B (CHB) patients.

AIM

We examined the efficiency of serum Mac-2 Binding Protein Glycosylation isomer (M2BPGi) in diagnosing liver fibrosis stages in CHB patients.

METHODS

A cross-sectional study was conducted on 177 adult CHB patients visiting the University Medical Center Ho Chi Minh City, Vietnam between October 2019 and December 2021. M2BPGi, ARFI, APRI, and FIB-4 were tested against FibroScan® for sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The optimal M2BPGi cut-off values were identified based on the area under the receiver operating characteristic (AUROC) curve.

RESULTS

There was a strong agreement between M2BPGi and FibroScan® (r = 0.77, P < 0.001). The optimal M2BPGi cut-off index (C.O.I) for detecting significant fibrosis (F ≥ 2) was 0.79 with an AUROC of 0.77, 67.3% sensitivity, 70% specificity, 60.6% NPV, and 75.3% PPV. Compared with APRI (61%) and FIB-4 (47%), M2BPGi had the greatest sensitivity for diagnosing F ≥ 2. M2BPGi combined with APRI yielded highest diagnosis performance for F ≥ 2 with an AUROC of 0.87. The optimal cut-off index of M2BPGi for diagnosing cirrhosis (F4) was 1.3 with an AUROC of 0.91, 88% sensitivity, 87.4% specificity, 97% NPV, and 61% PPV. The AUROC of M2BPGi for diagnosing F4 was comparable to that of ARFI (0.93).

CONCLUSIONS

With cut-off values of 0.79 C.O.I and 1.3 C.O.I, M2BPGi could be an effective method for diagnosing significant fibrosis and cirrhosis in CHB patients, respectively.

Diagnostic Performance of Acoustic Radiation Force Impulse Imaging in Evaluating Liver Fibrosis in Patients with Chronic Hepatitis B Infection: A Cross-Sectional Study

Background  Acoustic radiation force impulse point shear wave elastography (ARFI-pSWE), measuring shear-wave velocity (SWV), has been utilized to examine the liver stiffness caused by different etiologies. However, information on its reliability in staging liver fibrosis in chronic hepatitis B (CHB) patients is scarce.

Purpose  The aim of the study is to examine the diagnostic performance of ARFI-pSWE and determine the optimal SWV cut-off values to predict significant fibrosis ( F ≥2) and cirrhosis (F4) in CHB patients.

Material and Methods  All 114 adult CHB patients visiting the University Medical Center, Ho Chi Minh City, Vietnam between February 2019 and March 2021 underwent liver stiffness measurement using ARFI-pSWE and FibroScan. SWV results were tested against FibroScan for sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). The area under the receiver operating characteristic (AUROC) curve was used to identify the optimal SWV cut-off values.

Results  There was a strong agreement between ARFI-pSWE and FibroScan ( r  = 0.92, p <0.001). The optimal SWV cut-off value for detecting significant fibrosis was 1.37 m/s with an AUROC of 0.975, sensitivity of 83.3%, specificity of 100%, PPV of 100%, and NPV of 81%. The optimal cut-off value for predicting cirrhosis was 1.70 m/s with an AUROC of 0.986, sensitivity of 97%, specificity of 93%, PPV of 95%, and NPV of 96%.

Conclusion  ARFI-pSWE could be an effective technique for evaluating liver fibrosis in CHB patients. SWV cut-off values of 1.37 and 1.70 m/s could be used to diagnose significant fibrosis and cirrhosis, respectively.

Ultrasound elastography for the detection of capsular fibrosis in breast implants: First results

BACKGROUND

Capsular contractures around breast implants usually develop leading to pain and aesthetically inadequate results and ultimately often requires the replacement of the implants. Textured silicone implants are the most commonly placed implant, but polyurethane-coated implants are increasingly being used in an attempt to ameliorate the long-term complications associated with implant insertion.

AIM

Capsular contracture is traditionally classified using the Baker scale, a subjective classification system based upon clinical findings. Aim of this study was to evaluate the association between pain due capsular contraction, Baker score and different techniques of US elastography.

MATERIAL AND METHODS

Patients were contacted who had undergone an implant replacement due to capsular contracture. Inclusion criterion was the re-implantation of a PU-coated implant. In the third year after changing the implant a follow-up examination was performed in 16 patients with 23 implants. A conventional examination with anamnesis, tactile and visual findings to obtain a Baker score, and ultrasound examinations including shear wave elastography, ARFI and compound elastography were performed. In addition, pain was evaluated using a visual analogue scale (VAS).

RESULTS

The pain data showed a significant improvement (before implant exchange: 4.1±2.8 score points) with significance in favor of the current state (1.7±1.0 pain score points; p = 0.002). All patients suffered from less or no pain three years after exchange of the implant. Pain values and elastography (ARFI values) correlated well (r = 0,873), with increasing Baker score the ARFI values increased. US elastography evaluations can locally determine tissue density but correlate only to a limited extent with the test findings according to Baker. US elastography values of mammary gland tissue without implant did not differ from mammary gland tissue around implants.

CONCLUSION

Preoperative Baker scores prior to exchange and the current Baker scores at the follow-up showed significantly lower score points three years after exchange of the implants. Ultrasound elastography seems to be an objective classification of capsular fibrosis. These first results motivate to initiate a prospective multicenter investigation.

Hepatocellular Carcinoma and Non-Alcoholic Fatty Liver Disease: A Step Forward for Better Evaluation Using Ultrasound Elastography

Simple Summary

Non-alcoholic fatty liver disease (NAFLD) attracts a lot of attention, due to the increasing prevalence and progression to fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Consequently, new non-invasive, cost-effective diagnostic methods are needed. This review aims to explore the diagnostic performance of ultrasound (US) elastography in NAFLD and NAFLD-related HCC, adding a new dimension to the conventional US examination—the liver stiffness quantification. The vibration controlled transient elastography (VCTE), and 2D-Shear wave elastography (2D-SWE) are effective in staging liver fibrosis in NAFLD. VCTE presents the upside of assessing steatosis through the controlled attenuation parameter. Hereby, we critically reviewed the elastography techniques for the quantitative characterization of focal liver lesions (FLLs), focusing on HCC: Point shear wave elastography and 2D-SWE. 2D-SWE presents a great potential to differentiate malignant from benign FLLs, guiding the clinician towards the next diagnostic steps. As a disease-specific surveillance tool, US elastography presents prognostic capability, improving the NAFLD-related HCC monitoring.

Abstract

The increasing prevalence of non-alcoholic fatty liver disease (NAFLD) in the general population prompts for a quick response from physicians. As NAFLD can progress to liver fibrosis, cirrhosis, and even hepatocellular carcinoma (HCC), new non-invasive, rapid, cost-effective diagnostic methods are needed. In this review, we explore the diagnostic performance of ultrasound elastography for non-invasive assessment of NAFLD and NAFLD-related HCC. Elastography provides a new dimension to the conventional ultrasound examination, by adding the liver stiffness quantification in the diagnostic algorithm. Whilst the most efficient elastographic techniques in staging liver fibrosis in NAFLD are vibration controlled transient elastography (VCTE) and 2D-Shear wave elastography (2D-SWE), VCTE presents the upside of assessing steatosis through the controlled attenuation parameter (CAP). Hereby, we have also critically reviewed the most important elastographic techniques for the quantitative characterization of focal liver lesions (FLLs), focusing on HCC: Point shear wave elastography (pSWE) and 2D-SWE. As our paper shows, elastography should not be considered as a substitute for FLL biopsy because of the stiffness values overlap. Furthermore, by using non-invasive, disease-specific surveillance tools, such as US elastography, a subset of the non-cirrhotic NAFLD patients at risk for developing HCC can be detected early, leading to a better outcome. A recent ultrasomics study exemplified the wide potential of 2D-SWE to differentiate benign FLLs from malignant ones, guiding the clinician towards the next steps of diagnosis and contributing to better long-term disease surveillance.

MR-Based Electrical Conductivity Imaging of Liver Fibrosis in an Experimental Rat Model

BACKGROUND

Liver fibrosis is characterized by the excessive accumulation of extracellular matrix proteins. Electrical conductivity imaging at low frequency can provide novel contrast because the contrast mechanisms originate from the changes in the concentration and mobility of ions in the extracellular space.

PURPOSE

To evaluate the feasibility of an MR-based electrical conductivity imaging that can detect the changes in a tissue condition associated with the progression of liver fibrosis.

STUDY TYPE

Prospective phantom and animal study.

ANIMAL MODEL

Fibrosis was induced by weekly intraperitoneal injection of dimethylnitrosamine (DMN) in 45 male Sprague-Dawley rats.

FIELD STRENGTH/SEQUENCE

3T MRI with a multispin-echo pulse sequence.

ASSESSMENT

The percentage change of conductivity (Δσ, %) in the same region-of-interest (ROI) was calculated from the DMN-treated rats based on the values of the normal control rats. The percentage change was also calculated between the ROIs in each DMN-treated group.

STATISTICAL TESTS

One-way analysis of variance (ANOVA) and a two-sample t-test were performed.

RESULTS

Liver tissues in normal control rats showed a uniform conductivity distribution of 56.6 ± 4.4 (mS/m). In rats more than 5 weeks after induction, the fibrous region showed an increased conductivity of ≥12% compared to that of the corresponding normal control rats. From regional comparisons in the same liver, the fibrous region showed an increased conductivity of ≥11% compared to the opposite, less induced region of rats more than 5 weeks after induction. Liver samples from the fibrous region represent tissue damages such as diffuse centrilobular congestion with marked dilatation of central veins from the histological findings. Immunohistochemistry revealed significant levels of attenuated fibrosis and increased inflammatory response.

DATA CONCLUSION

The increased conductivity in the fibrous region is related to the changes of the extracellular space. The correlation between the collagen deposition and conductivity changes is essential for future clinical studies. Level of Evidence 2 Technical Efficacy Stage 2 J. MAGN. RESON. IMAGING 2021;53:554-563.

Wisteria floribunda agglutinin-positive human Mac-2-binding protein as a predictive marker of liver fibrosis in human immunodeficiency virus/hepatitis C virus coinfected patients

AIM

In human immunodeficiency virus (HIV) and hepatitis C virus (HCV) coinfected patients, the progression of liver failure is reported to be more aggressive than that in HCV mono-infected patients. Wisteria floribunda agglutinin-positive human Mac-2-binding protein (WFA⁺ -M2BP) is well recognized as a liver fibrosis glycobiomarker with a unique fibrosis-related glycoalteration. We analyzed HIV/HCV coinfected patients' M2BP levels as a possible marker for predicting liver fibrosis.

METHODS

M2BP was measured in 31 HIV/HCV coinfected patients, and we analyzed the correlation between WFA⁺ -M2BP and several markers of fibrosis, liver function, and tumor markers. We compared the WFA⁺ -M2BP levels in HIV/HCV coinfected patients with those of HCV mono-infected patients by performing a propensity score matching analysis.

RESULTS

In the HIV/HCV coinfected patients, the serum level of WFA⁺ -M2BP was well correlated with the markers type IV collagen, hyaluronic acid, and alpha-fetoprotein, but not protein induced by vitamin K absence-II. In the propensity score matching with HCV mono-infected patients, the WFA⁺ -M2BP levels were significantly higher in the HIV/HCV coinfected patients compared with the levels in the HCV mono-infected patients.

CONCLUSION

In conclusion, WFA⁺ -M2BP might be a feasible predictive marker of fibrosis in HIV/HCV coinfected patients.

Skin-Liver Distance and Interquartile Range-Median Ratio as Determinants of Interoperator Concordance in Acoustic Radiation Force Impulse Imaging

Context and Aims:

The accuracy of acoustic radiation force impulse (ARFI) ultrasound compared to liver biopsy is higher when there is concordance between F-scores of two or more operators. We hypothesized that when the first operator interquartile range/median-velocity ratio (IMR) is <0.3 and skin-liver distance (SLD) is <2.5 cm, there is greater interoperator concordance and a second operator is not necessary.

Subjects and Methods:

Two-operator ARFI ultrasound measurements (F-score, SLD, and IMR) were recorded for 927 consecutive patients. Chi-squared testing compared interoperator concordance for SLD <2.5 cm versus SLD ≥2.5 cm and IMR <0.3 versus IMR ≥0.3 when SLD <2.5 cm, in each of the F-score groups of 0/1, 2, 3, and 4.

Results:

Statistically significant differences were demonstrated between SLD <2.5 cm and SLD ≥2.5 cm groups for F-scores 0/1 or 4 (P = 0.005) and F-scores 2 or 3 (P < 0.001). Concordance, when SLD measured <2.5 cm, was more than 85% for all F-score groups. In the SLD <2.5 cm group, concordance fell below 85% when IMR ≥0.3, for all F-scores except F2. Specifically, P values comparing IMR <0.3 and IMR ≥0.3 in the various first operator F-score groups were P = 0.040 for F0/F1, P = 0.580 for F2, P = 0.342 for F3, and P < 0.001 for F4.

Conclusions:

ARFI measurements from one operator can be considered acceptable when SLD <2.5 cm and IMR <0.3. Otherwise, adding a second operator can improve confidence in the result.

Performance of common imaging techniques vs serum biomarkers in assessing fibrosis in patients with chronic hepatitis B: A systematic review and meta-analysis

BACKGROUND

Noninvasive biomarkers have been developed to predict hepatitis B virus (HBV) related fibrosis owing to the significant limitations of liver biopsy. Both serum biomarkers and imaging techniques have shown promising results and may improve the evaluation of liver fibrosis. However, most of the previous studies focused on the diagnostic effects of various imaging techniques on fibrosis in all chronic liver diseases.

AIM

To compare the performance of common imaging methods and serum biomarkers for prediction of significant fibrosis caused only by HBV infection.

METHODS

A systematic review was conducted on the records available in PubMed, EMBASE, and the Cochrane Library electronic databases until December 2018. We systematically assessed the effectiveness of two serum biomarkers and three imagine techniques in predicting significant fibrosis solely caused by HBV infection. The serum biomarkers included aspartate aminotransferase-to-platelet ratio index (APRI) and fibrosis index based on the 4 factors (FIB-4). The three imaging techniques included acoustic radiation force impulse (ARFI), FibroScan, and magnetic resonance elastography (MRE). Three parameters, the area under the summary receiver operating characteristic curve (AUSROC), the summary diagnostic odds ratio, and the summary sensitivity and specificity, were used to examine the accuracy of all tests for liver fibrosis.

RESULTS

Out of 2831 articles evaluated for eligibility, 204 satisfied the predetermined inclusion criteria for this current meta-analysis. Eventually, our final data contained 81 studies. The AUSROCs of serum biomarkers of APRI and FIB-4 were both 0.75. For imaging techniques (ARFI, FibroScan, and MRE), the areas were 0.89, 0.83, and 0.97, respectively. The heterogeneities of ARFI and FibroScan were statistically significant (I² > 50%). The publication bias was not observed in any of the serum biomarkers or imaging methods.

CONCLUSION

These five methods have attained an acceptable level of diagnostic accuracy. Imaging techniques, MRE in particular, demonstrate significant advantages in accurately predicting HBV-related significant fibrosis, while serum biomarkers are admissible methods.

Liver Disease in Human Immunodeficiency Virus Infection

Liver disease in human immunodeficiency virus (HIV) remains a main cause of morbidity and mortality. Liver-related morbidity and mortality can be caused by multiple etiologic factors, including opportunistic infections, direct and indirect effects of antiretrovirals, direct and indirect effects of HIV, and viral hepatitides. These factors present with varied liver pathophysiologic mechanisms that lead to abnormalities in liver enzymes and synthetic function test, followed by distinct clinical presentations. This article elucidates the direct effects on HIV in the liver and explores the diagnostic and management challenges in patients with HIV in the era of highly active antiretroviral treatment.

Optimal Use of Transient Elastography and Acoustic Radiation Force Impulse to Stage Liver Fibrosis in HIV/HCV-Coinfected Patients in Clinical Practice

OBJECTIVES

Liver fibrosis (LF) is crucial for the individualized management of patients with hepatitis C virus (HCV). We evaluated the concordance between two noninvasive methods for staging LF, transient elastography (TE) and acoustic radiation force impulse (ARFI), in patients coinfected with human immunodeficiency virus and HCV. We propose an algorithm for optimal use of both techniques in routine clinical practice.

METHODS

A total of 89 human immunodeficiency virus/HCV-coinfected patients underwent TE and ARFI on the same day. The kappa index was used to assess concordance between the techniques. An algorithm combining ARFI and TE was proposed based on the independent factors associated with a kappa index greater than or equal to 0.70, obtained from a multiple regression analysis. We performed a cost-effectiveness analysis. The study was approved by our institutional review board and all patients signed the informed consent.

RESULTS

Concordance between TE and ARFI for F2, F3, and F4 was 0.55, 0.59, and 0.69, respectively. Ultrasound normal spleen size (odds ratio [OR], 0.20; 95% confidence interval [CI], 0.05-0.91) and high viral load (OR, 0.36; 95% CI, 0.17-0.77) reduced the probability of agreement between TE and ARFI, whereas ultrasound normal left liver lobe size (OR, 3.32; 95% CI, 1.21-9.10) increased this probability. The algorithm revealed that LF was adequately assessed in 74.16%, with 25.84% of patients misclassified. The incremental cost-effectiveness ratio of TE compared with ARFI to increase concordance by 1% was €8.86.

CONCLUSIONS

Concordance between TE and ARFI was moderate. In the algorithm we proposed, ARFI was cost-effective as a first technique for the staging of LF in the study population.

Aspartate transaminase-platelet ratio and Fibrosis-4 indices as effective markers for monitoring esophageal varices in HIV/hepatitis C virus co-infected patients due to contaminated blood products for hemophilia

AIM

We examined the feasibility of the aspartate transaminase (AST)-platelet ratio index (APRI) and Fibrosis-4 (FIB4) score, which are well-established markers for liver fibrosis, as indicators for monitoring esophageal varices in patients who were co-infected with HIV and hepatitis C virus (HCV) due to contaminated blood products for hemophilia in Japan.

METHODS

Forty-three HIV/HCV co-infected patients were enrolled. All were hemophilic men (median age 41 years; range, 29-66 years). We analyzed the correlations between fibrosis indices (APRI, FIB4) and various liver function tests, fibrosis markers, liver stiffness measured by acoustic radiation force impulse elastography, and the findings of gastrointestinal endoscopy.

RESULTS

Both APRI and FIB4 were well correlated with several of the factors related to liver fibrosis and the existence of esophageal varices in the patients. The cut-off values for detecting esophageal varices estimated as the area under the receiver operating characteristic curve were 0.85 for APRI and 1.85 for FIB4.

CONCLUSION

In patients co-infected with HIV/HCV due to contaminated blood products for hemophilia, APRI and FIB4 are effective for monitoring esophageal varices, even among patients who are apparently doing well with good liver function as Child-Pugh grade A.

Acoustic Radiation Force Impulse Imaging for Assessing Liver Fibrosis Preoperatively in Infants With Biliary Atresia: Comparison With Liver Fibrosis Biopsy Pathology

OBJECTIVES

The purpose of this study was to investigate the diagnostic performance of acoustic radiation force impulse (ARFI) in assessing liver fibrosis preoperatively in infants with biliary atresia (BA).

METHODS

A total of 50 consecutive infants with BA and 50 healthy infants who underwent ARFI examination were recruited. Siemens Acuson S2000 in Virtual Touch Quantification mode (Siemens Medical Solutions, Mountain View, CA) was used to measure shear wave speeds (SWSs). All infants with BA underwent a liver biopsy within 3 days after ARFI imaging. The liver fibrosis stages of specimens were defined according to the Batts-Ludwig scoring system. The correlation analysis was performed between SWSs and pathological findings. Cut-off values were determined using receiver operating characteristic (ROC) curves.

RESULTS

The mean SWS in the BA group was significantly higher than controls (mean ± standard deviation): 1.89 ± 0.45 versus 1.12 ± 0.06 m/s; P < .001). A significant correlation was found between the SWSs and fibrosis stages (r = 0.719, P < .001). The cut-off value for predicting significant fibrosis (F ≥ 2), severe fibrosis (F ≥ 3), and cirrhosis (F = 4) was 1.53, 1.80 and 2.16 m/s, respectively, and the area under the ROC curve was 0.823, 0.884 and 0.917, respectively.

CONCLUSIONS

Acoustic radiation force impulse imaging showed significant correlation with the severity of liver fibrosis by comparing it with liver fibrosis biopsy pathology. It may be an effective method for liver fibrosis assessment, prognosis prediction, and clinical management in infants with BA.

Clinical usefulness and performance of acoustic radiation force impulse in patients with chronic hepatitis B

AIM

The aim of this study was to evaluate the performance of acoustic radiation force impulse (ARFI) compared with liver biopsy in quantifying fibrosis levels in patients with chronic hepatitis B (CHB).

PATIENTS AND METHODS

The study was approved by the institutional review board at our hospital. One hundred CHB patients and 30 healthy controls (130 individuals) were included in the study. ARFI measurements were performed on all of these cases. CHB was diagnosed when serum hepatitis surface antigen was positive for more than 6 months and when persistent or intermittent elevations in alanine aminotransferase and aspartate aminotransferase levels and histopathological changes in liver biopsy were present. Liver biopsies were taken as a reference standard for 100 CHB patients. Liver biopsy samples were examined using the Ishak scoring system and compared with ARFI velocity values.

RESULTS

Of the 130 participants, 107 (82.3%) were men and 23 (17.7%) were women. Thirty of these participants were healthy controls and their fibrotic score was evaluated as an Ishak fibrosis score of 0. A gradual increase in the mean velocity value was obtained for fibrosis scores F0-F6 (Ishak fibrosis score) in our study. A strong positive correlation was found between the mean velocity values and fibrosis scores of liver biopsy that were performed on liver segment 8. The area under the receiver operating characteristic curve was used to detect the best cutoff velocity values, and no or mild fibrosis (F≤2), significant fibrosis (F≥3), and severe fibrosis (F≥5) were calculated to be 0.95, 1.75, and 2.55 m/s, respectively. When a cutoff value of 1.75 m/s was used, ARFI had a sensitivity of 83% and a specificity of 98% in differentiating patients with fibrosis score F≤2 versus F≥3.

CONCLUSION

ARFI elastography in patients with CHB can be considered an easy-to-use and accurate noninvasive tool to evaluate the severity of liver fibrosis.

Concordance of non-invasive mechanical and serum tests for liver fibrosis evaluation in chronic hepatitis C

AIM

To determine the sensitivity and specificity of liver stiffness measurement (LSM) and serum markers (SM) for liver fibrosis evaluation in chronic hepatitis C.

METHODS

Between 2012 and 2014, 81 consecutive hepatitis C virus (HCV) patients had METAVIR score from liver biopsy compared with concurrent results from LSM [transient elastography (TE) [FibroScan^®/ARFI technology (Virtual Touch^®)] and SM [FIB-4/aspartate aminotransferase-to-platelet ratio index (APRI)]. The diagnostic performance of these tests was assessed using receiver operating characteristic curves. The optimal cut-off levels of each test were chosen to define fibrosis stages F ≥ 2, F ≥ 3 and F = 4. The Kappa index set the concordance analysis.

RESULTS

Fifty point six percent were female and the median age was 51 years (30-78). Fifty-six patients (70%) were treatment-naïve. The optimal cut-off values for predicting F ≥ 2 stage fibrosis assessed by TE were 6.6 kPa, for acoustic radiation force impulse (ARFI) 1.22 m/s, for APRI 0.75 and for FIB-4 1.47. For F ≥ 3 TE was 8.9 kPa, ARFI was 1.48 m/s, APRI was 0.75, and FIB-4 was 2. For F = 4, TE was 12.2 kPa, ARFI was 1.77 m/s, APRI was 1.46, and FIB-4 was 3.91. The APRI could not distinguish between F2 and F3, P = 0.92. The negative predictive value for F = 4 for TE and ARFI was 100%. Kappa index values for F ≥ 3 METAVIR score for TE, ARFI and FIB-4 were 0.687, 0.606 and 0.654, respectively. This demonstrates strong concordance between all three screening methods, and moderate to strong concordance between them and APRI (Kappa index = 0.507).

CONCLUSION

Given the costs and accessibility of LSM methods, and the similarity with the outcomes of SM, we suggest that FIB-4 as well as TE and ARFI may be useful indicators of the degree of liver fibrosis. This is of particular importance to developing countries.

Non-invasive evaluation of liver fibrosis by acoustic radiation force impulse and aminotransferase:platelet ratio index in chronic hepatitis C

In a previous issue of the World Journal of Gastroenterology, we have read the article by Li et al with great interest. We would like to thank the authors for their comprehensive contribution. However, it is our wish to make minor criticism over the present study from the perspective of methodology.

Learning curve and intra/interobserver agreement of transient elastography in chronic hepatitis C patients with or without HIV co-infection

BACKGROUND AND OBJECTIVES

Liver stiffness measurement (LSM) by transient elastography has been validated as a noninvasive method to stage liver fibrosis. Few studies have evaluated the learning curve of this method and its reproducibility has led to controversy results. We aimed to evaluate the intra- and interobserver agreement of transient elastography as well as its learning curve for definition of an experimented operator.

METHODS

We retrospectively analyzed 922 examinations performed in 544 patients during a training program of transient elastography. Patients with chronic hepatitis C with or without HIV co-infection that had two examinations by the training operator (intraobserver analysis; n=125) or examination by both training and experimented operators (interobserver analysis; n=151) in the same day were included. LSM was converted to METAVIR score: <7.1 as F0F1, 7.1-9.4 as F2, 9.5-12.4, as F3 and >12.4 kPa as F4.

RESULTS

The overall intra- and interobserver intraclass correlation coefficient [ICC 95% CI] were 0.926 (0.901-0.951) and 0.912 (0.885-0.939), respectively. Measurements were correlated [Spearman's] in intra- [0.906, P<0.0001] and interobserver [0.907, P<0.0001] analysis. Reliability values [kappa (SE)] were k=0.74 (0.09) and k=0.85 (0.08) for fibrosis stages F ≥ 2 and k=0.77 (0.09) and k=0.75 (0.08) for cirrhosis in intra- and interobserver analysis, respectively. Agreement was improved when operator's experience was higher than 100 exams. However, it was observed discordance for fibrosis staging between examinations in a quarter of patients.

CONCLUSION

Although there was a considerable discrepancy on fibrosis staging between examinations and a small power, transient elastography had an acceptable reproducibility in our population. Performance of at least 100 examinations should be used to define an experimented operator.

Liver fibrosis in human immunodeficiency virus/hepatitis C virus coinfection: Diagnostic methods and clinical impact

Several non-invasive surrogate methods have recently challenged the main role of liver biopsy in assessing liver fibrosis in hepatitis C virus (HCV)-monoinfected and human immunodeficiency virus (HIV)/HCV-coinfected patients, applied to avoid the well-known side effects of liver puncture. Serological tests involve the determination of biochemical markers of synthesis or degradation of fibrosis, tests not readily available in clinical practice, or combinations of routine tests used in chronic hepatitis and HIV/HCV coinfection. Several radiologic techniques have also been proposed, some of which commonly used in clinical practice. The studies performed to compare the prognostic value of non-invasive surrogate methods with that of the degree of liver fibrosis assessed on liver tissue have not as yet provided conclusive results. Each surrogate technique has shown some limitations, including the risk of over- or under-estimating the extent of liver fibrosis. The current knowledge on liver fibrosis in HIV/HCV-coinfected patients will be summarized in this review article, which is addressed in particular to physicians involved in this setting in their clinical practice.

Circulating miRNA-122 levels are associated with hepatic necroinflammation and portal hypertension in HIV/HCV coinfection

BACKGROUND

Introduction of combined antiretroviral therapy (cART) has improved survival of HIV infected individuals, while the relative contribution of liver-related mortality increased. Especially in HIV/HCV-coinfected patients hepatic fibrosis and portal hypertension represent the main causes of liver-related morbidity and mortality. Circulating miRNA-122 levels are elevated in HIV patients and have been shown to correlate with severity of liver injury. However, the association of miRNA-122 levels and hepatic fibrosis and portal hypertension remains to be explored in HIV/HCV coinfection.

METHODS

From a total of 74 (31% female) patients with HIV/HCV coinfection were included. Serum levels of miRNA-122 were analyzed by quantitative polymerase chain reaction (PCR) and normalized to SV-40 spike-in RNA. Hepatic venous pressure gradient (HVPG) was measured in 52 (70%) patients and the fibrosis stage was determined in 63 (85%) patients using transient elastography.

RESULTS

The levels of circulating miRNA-122 were increased in HIV/HCV coinfected patients and significantly correlated with the alanine aminotransferase (ALT) (rs = 0.438; p<0.001) and aspartate transaminase AST values (rs = 0.336; p = 0.003), but not with fibrosis stage (p = n.s.). Interestingly, miRNA-122 levels showed an inverse correlation with hepatic venous pressure gradient (HVPG) (rs = -0.302; p = 0.03).

CONCLUSION

Elevated miRNA-122 levels are associated with liver injury, and with low HVPG. Though, miRNA-122 levels are not suitable to predict the degree of fibrosis, they might function as indicators for portal hypertension in HIV/HCV coinfected patients.