[Usefulness of liver stiffness measurement for predicting the presence of esophageal varices in patients with liver cirrhosis]

Meta-analysis of the accuracy of transient elastography in measuring liver stiffness to diagnose esophageal varices in cirrhosis

BACKGROUD

To assess the diagnostic performance of transient elastography (TE) in detecting the presence and size of esophageal varices (EV) in cirrhotic patients.

METHODS

We searched PubMed, Web of Science, Wiley Online Library, Science Direct, China National Knowledge Infrastructure, WeiPu, WanFang database, and Baidu Scholar to identify studies that evaluated the diagnostic accuracy of TE in liver stiffness measurement, compared with esophagogastroduodenoscopy (EGD), for the detection of the presence and degree of EV in cirrhosis.

RESULTS

We included 32 studies in the presence of any EV (grade 1-3; n = 4082), 27 studies on substantial EV (grade 2-3; n = 5221) and 5 studies on large EV (grade 3). The pooled sensitivity, specificity, and diagnostic odds ratio (DOR) were 0.8 (95% CI, 0.78-0.86), 0.68 (95% CI, 0.62-0.74), and 10 (95% CI, 7-14) for any EV; 0.81 (95% CI, 0.77-0.85), 0.72 (95% CI, 0.66-0.77), and 11 (95% CI, 8-15) for substantial EV; and 0.92 (95% CI, 0.83-0.96), 0.78 (95% CI, 0.70-0.85), and 40 (95% CI, 15-107) for large EV. Subgroup analysis revealed that the heterogeneity among studies on any EV could potentially be explained by study location, proportion of Child A, and time interval between TE and EGD; for substantial EV, the proportion of Child A, etiology of cirrhosis, and the time interval between TE and EGD were important heterogeneity factors. Publication bias was found among studies evaluating diagnostic performance of TE for any EV.

CONCLUSION

TE is a good tool for detecting the presence and degree of EV; however, in determination of the liver stiffness cutoff values means that TE is only cautiously used in clinical practice.

Elastography methods for the non-invasive assessment of portal hypertension

The gold standard to assess the presence and severity of portal hypertension remains the hepatic vein pressure gradient, however the recent development of non-invasive assessment using elastography techniques offers valuable alternatives. In this review, we discuss the diagnostic accuracy and utility of such techniques in patients with portal hypertension due to cirrhosis. Areas covered: A literature search focused on liver and spleen stiffness measurement with different elastographic techniques for the assessment of the presence and severity of portal hypertension and oesophageal varices in people with chronic liver disease. The combination of elastography with parameters such as platelet count and spleen size is also discussed. Expert commentary: Non-invasive assessment of liver fibrosis and portal hypertension is a validated tool for the diagnosis and follow-up of patients. Baveno VI recommended the combination of transient elastography and platelet count for ruling out varices needing treatment in patients with compensated advanced chronic liver disease. Assessment of aetiology specific cut-offs for ruling in and ruling out clinically significant portal hypertension is an unmet clinical need. The incorporation of spleen stiffness measurements in non-invasive algorithms using validated software and improved measuring scales might enhance the non-invasive diagnosis of portal hypertension in the next 5 years.

Diagnostic accuracy of transient elastography (FibroScan) in detection of esophageal varices in patients with cirrhosis: A meta-analysis

AIM

To investigate the diagnostic accuracy of FibroScan (FS) in detecting esophageal varices (EV) in cirrhotic patients.

METHODS

Through a systemic literature search of multiple databases, we reviewed 15 studies using endoscopy as a reference standard, with the data necessary to calculate pooled sensitivity (SEN) and specificity (SPE), positive and negative LR, diagnostic odds ratio (DOR) and area under receiver operating characteristics (AUROC). The quality of the studies was rated by the Quality Assessment of Diagnostic Accuracy studies-2 tool. Clinical utility of FS for EV was evaluated by a Fagan plot. Heterogeneity was explored using meta-regression and subgroup analysis. All statistical analyses were conducted via Stata12.0, MetaDisc1.4 and RevMan5.

RESULTS

In 15 studies (n = 2697), FS detected the presence of EV with the summary sensitivities of 84% (95%CI: 81.0%-86.0%), specificities of 62% (95%CI: 58.0%- 66.0%), a positive LR of 2.3 (95%CI: 1.81-2.94), a negative LR of 0.26 (95%CI: 0.19-0.35), a DOR of 9.33 (95%CI: 5.84-14.92) and an AUROC of 0.8262. FS diagnosed the presence of large EV with the pooled SEN of 0.78 (95%CI: 75.0%-81.0%), SPE of 0.76 (95%CI: 73.0%-78.0%), a positive and negative LR of 3.03 (95%CI: 2.38-3.86) and 0.30 (95%CI: 0.23-0.39) respectively, a summary diagnostic OR of 10.69 (95%CI: 6.81-16.78), and an AUROC of 0.8321. A meta-regression and subgroup analysis indicated different etiology could serve as a potential source of heterogeneity in the diagnosis of the presence of EV group. A Deek’s funnel plot suggested a low probability for publication bias.

CONCLUSION

Using FS to measure liver stiffness cannot provide high accuracy for the size of EV due to the various cutoff and different etiologies. These limitations preclude widespread use in clinical practice at this time; therefore, the results should be interpreted cautiously given its SEN and SPE.

Liver stiffness measurement, better than APRI, Fibroindex, Fib-4, and NBI gastroscopy, predicts portal hypertension in patients with cirrhosis

Liver stiffness measurement (LSM) is frequently used as non-invasive alternative for liver fibrosis including cirrhosis, which can lead to portal hypertension. This study was conducted to evaluate the predictive value of LSM in cirrhosis-induced portal hypertension patients. Between July 2011 and December 2013, 153 participants were enrolled into a single-center, prospective, cross-sectional study. Each subject received both gastroscopy and LSM. Baseline biochemical, APRI, Fibroindex, and Fib-4 were also performed. LSM of cirrhosis patients with portal hypertension was significantly higher compared to those without portal hypertension (P < 0.05). A LSM ≥ 13.6 kPa had a sensitivity of 83.87 % and a specificity of 72.53 % with an accuracy of 77.1 for the prediction of portal hypertension, which are higher than those of APRI, Fib-4, and Fibroscan separately. A combination of Fibroscan combined with Fib-4 achieved a maximum AUC of 0.833 and accuracy of 77.8. Discriminant and internal validation analysis showed that Fibroscan plus APRI obtained a lower false negative rate compared to Fibroscan plus Fib-4 and Fibroscan plus Fibroindex (9.68, 17.74, and 11.29 %, respectively). A good relationship was found between LSM and NBI mean optical density both by linear and polynomial correlation analysis (r = 0.5533 and r = 0.7349, both P < 0.001). There was a trend toward a better performance of LSM for assessing portal hypertension compared with NBI gastroscopy mean optical density (P = 0.028 and P = 0.05, respectively). Better than APRI, Fibroindex, Fib-4, and NBI gastroscopy, LSM can predict portal hypertension in cirrhosis patients. A LSM of 13.6 kPa can be considered to be the predictive value for portal hypertension.

Assessment of risk of complications in cirrhosis using portal thallium scans

AIM: To investigate the usefulness of a novel thallium scan shunt index for assessing portosystemic shunt-related cirrhotic complications.

METHODS: We enrolled 209 chronic hepatitis B-related cirrhosis patients. After rectal thallium instillation, radioactive isotope activity in the heart and liver was measured. The ratio of radiation uptake between the heart and the liver was calculated (the shunt index). This value indicates the degree of portosystemic circulation shunting. Blood tests, serum biochemistry tests, abdominal ultrasonography, gastroscopy and examination of clinical features such as the occurrence of varices, bleeding and hepatic encephalopathy were performed. Multivariate analysis was used to identify independent risk factors for complications. We compared the cumulative incidence rates of complications during the follow-up period.

RESULTS: The thallium scan shunt index was significantly higher in the decompensated liver cirrhosis group than in the compensated liver cirrhosis group (0.91 ± 0.39 vs 0.39 ± 0.32, P < 0.001). It was also higher in the varices group, the hepatic encephalopathy group, and the variceal bleeding group than in the control group (P < 0.001). Multivariate analysis showed that the index was an independent risk factor for predicting decompensated liver cirrhosis. When the cut-off value was 0.75, the shunt index had a sensitivity of 82.6%, a specificity of 84%, a positive predictive value of 61.5%, and a negative predictive value of 94.4% in diagnosing decompensated cirrhosis. When the shunt index was greater than 0.75, there was a significant increase in the number of decompensated events.

CONCLUSION: The thallium shunt index is a good predictor of cirrhosis-related complications.

Can transient elastography, Fib-4, Forns Index, and Lok Score predict esophageal varices in HCV-related cirrhotic patients?

BACKGROUND

Gastroesophageal varices are present in approximately 50% of patients with liver cirrhosis. The aim of this study was to evaluate liver stiffness measurement (LSM), Fib-4, Forns Index and Lok Score as noninvasive predictors of esophageal varices (EV).

METHODS

This prospective study included 65 patients with HCV-related liver cirrhosis. All patients underwent routine laboratory tests, transient elastograhy (TE) and esophagogastroduodenoscopy. FIB-4, Forns Index and Lok Score were calculated. The diagnostic performances of these methods were assessed using sensitivity, specificity, positive predictive value, negative predictive value, accuracy and receiver operating characteristic curves.

RESULTS

All predictors (LSM, FIB-4, Forns Index and Lok Score) demonstrated statistically significant correlation with the presence and the grade of EV. TE could diagnose EV at a cutoff value of 18.2kPa. Fib-4, Forns Index, and Lok Score could diagnose EV at cutoff values of 2.8, 6.61 and 0.63, respectively. For prediction of large varices (grade 2, 3), LSM showed the highest accuracy (80%) with a cutoff of 22.4kPa and AUROC of 0.801. Its sensitivity was 84%, specificity 72%, PPV 84% and NPV 72%. The diagnostic accuracies of FIB-4, Forns Index and Lok Score were 70%, 70% and76%, respectively, at cutoffs of 3.3, 6.9 and 0.7, respectively. For diagnosis of large esophageal varices, adding TE to each of the other diagnostic indices (serum fibrosis scores) increased their sensitivities with little decrease in their specificities. Moreover, this combination decreased the LR- in all tests.

CONCLUSION

Noninvasive predictors can restrict endoscopic screening. This is very important as non invasiveness is now a major goal in hepatology.

Clinical application of liver stiffness measurement using transient elastography in chronic liver disease from longitudinal perspectives

Accurate determination of the presence and degree of fibrosis in liver is of great importance, because the prognosis and management strategies for chronic liver disease depend mainly on these factors. To date, liver biopsy (LB) remains the “gold standard” for assessing the severity of liver fibrosis; however, LB is often limited by its invasiveness, sampling error, and intra/inter-observer variability in histological interpretation. Furthermore, repeated LB examinations within a short time interval are indeed ineligible in a real clinical practice. Thus, due to the pressing need for non-invasive surrogates for liver fibrosis, transient elastography (TE), as a novel ultrasound based technology, has allowed a noninvasive measurement of liver stiffness and has gained in popularity over recent years. In the past few years, additional roles for transient TE beyond the initial purpose of a non-invasive surrogate for LB have included the prediction of the most two critical consequences of fibrosis progression: the development of portal hypertension-related complications and hepatocellular carcinoma. This indicates that the role of transient TE is not merely limited to reducing the need for LB, but transient TE can enable the establishment of tailored management strategies by providing more detailed prognostic information. In particular, under the concept in which the clinical course of liver fibrosis is dynamic and bidirectional, especially when appropriate intervention is commenced, transient TE can be used to track the dynamic changes in fibrotic burden during antiviral or antifibrotic treatment. This review discussed extended applications of transient TE in prediction of the development of real clinical endpoints from a longitudinal perspective.

Liver and spleen stiffness measured by acoustic radiation force impulse elastography for noninvasive assessment of liver fibrosis and esophageal varices in patients with chronic hepatitis B

OBJECTIVES

To evaluate the performance of liver and spleen stiffness measured by acoustic radiation force impulse (ARFI) elastography for noninvasive assessment of liver fibrosis and esophageal varices in patients with chronic hepatitis B virus.

METHODS

Two hundred sixty-four participants, of whom 60 were healthy volunteers (classified as stage 0), 66 were patients with chronic hepatitis B who had undergone liver biopsy, and 138 were patients with hepatitis B-related cirrhosis, were enrolled in this study. Median liver and spleen stiffness values (meters per second) from 10 successful measurements per participant were obtained. Patients with cirrhosis were examined by upper endoscopy.

RESULTS

Significant linear correlations were found between liver (Spearman ρ = 0.87; P < .001) and spleen (Spearman ρ = 0.76; P < .001) stiffness and the fibrosis stage. Liver and spleen stiffness values increased as fibrosis progressed; however, overlaps in liver stiffness were detected in stages 0 and 1 and 1 and 2, and overlaps in spleen stiffness were observed in stages 0 and 1, 1 and 2, and 2 and 3. Liver stiffness cutoff values were 1.69 m/s for predicting stage 3 or greater (area under the receiver operating characteristic curve [AUROC] = 0.99) and 1.88 m/s for stage 4 (AUROC = 0.97). The spleen stiffness cutoff value was 2.72 m/s for stage 4 (AUROC = 0.96). Liver stiffness was not correlated with the varix grade, whereas a significant linear correlation (Spearman ρ = 0.65; P < .001) between spleen stiffness and the varix grade was found. The optimal spleen stiffness cutoff value for predicting varices was 3.16 m/s (AUROC = 0.83).

CONCLUSIONS

Liver and spleen stiffness values measured by ARFI elastography are reliable predictors of liver fibrosis. Spleen stiffness measured by ARFI can be used as a non-invasive method for determining the presence and severity of esophageal varices; however, evidence to support a similar role for liver stiffness is lacking.

Towards noninvasive detection of oesophageal varices

Current guidelines recommend that all cirrhotic patients should undergo screening endoscopy at diagnosis to identify patients with varices at high risk of bleeding who will benefit from primary prophylaxis. This approach places a heavy burden upon endoscopy units and the repeated testing over time may have a detrimental effect on patient compliance. Noninvasive identification of patients at highest risk for oesophageal varices would limit investigation to those most likely to benefit. Upper GI endoscopy is deemed to be the gold standard against which all other tests are compared, but is not without its limitations. Multiple studies have been performed assessing clinical signs and variables relating to liver function, variables relating to liver fibrosis, and also to portal hypertension and hypersplenism. Whilst some tests are clearly preferable to patients, none appear to be as accurate as upper GI endoscopy in the diagnosis of oesophageal varices. The search for noninvasive tests continues.

[Changes in liver stiffness after acute or chronic liver injury due to viral hepatitis--does fibrosis exist after recovery from acute viral hepatitis?]

BACKGROUND/AIMS

Liver stiffness (LS) measurement by transient elastography can estimate the degrees of liver fibrosis in patients with chronic liver disease. However, longitudinal data of LS after recovery of acute viral hepatitis are still lacking. In the present study, we aimed to evaluate among LS of patients at various stages of viral hepatitis and normal control.

METHODS

Patients who had admitted at Korea University Ansan Hospital between January 2006 and January 2007 due to acute viral hepatitis and recovered were recruited (group A, n=22). We compared the liver biochemistry and LS of group A with those of healthy control group (group B, n=23), current acute viral hepatitis group (group C, n=49), and chronic viral hepatitis group (group D, n=66).

RESULTS

Mean ALT, total bilirubin, and LS level of group A were not different from group B (p=0.318, p=0.116, p=0.125, respectively). However, group A had lower ALT, total bilirubin, and LS values compared to group C (all p<0.001), and lower ALT and LS values compared to group D (p=0.007, p<0.001). The mean total bilirubin was not significantly different from group D (p=0.117).

CONCLUSIONS

Our data suggest that liver fibrosis is a long-term sequela of chronic hepatitis, and not developed in patients who recovered from acute viral hepatitis.

A review of the natural history of chronic hepatitis B in the era of transient elastography

Understanding the natural history of chronic hepatitis B is important in order to predict the prognosis, to stratify the risk of hepatocellular carcinoma and to select appropriate candidates for antiviral treatment. Liver fibrosis is the pathogenic process that leads to liver cirrhosis. The study of liver fibrosis in the past has largely been hampered by the invasive nature of a liver biopsy. Most liver biopsy series represent biased populations with more active disease. Transient elastography is a reliable and non-invasive measurement of liver fibrosis that allows the study of liver fibrosis among patients without clinical indication for liver biopsy. Large studies using transient elastography in patients with predominantly normal alanine aminotransferase levels have been reported recently. The different roles of patient age, hepatitis B virus DNA and alanine aminotransferase levels in the risk stratification for advanced liver fibrosis have been defined in hepatitis B e antigen-positive and hepatitis B e antigen-negative chronic hepatitis B patients. The relationship between metabolic syndrome and chronic hepatitis B is also explored. In this review, new insights from studies using transient elastography on the natural history of chronic hepatitis B with special focus on liver fibrosis will be summarized and discussed.