瞬时弹性扫描诊断肝纤维化准确性研究

目的验证瞬时弹性扫描（FibroScan）诊断肝纤维化的准确性。方法选取141例慢性肝病患者,每例均进行肝脏活体组织检查,并应用瞬时弹性扫描仪测量肝脏硬度,以病理检查结果为金标准,验证FibroScan诊断肝纤维化的准确性。结果肝脏硬度与肝纤维化程度密切相关,Kendall相关系数为0．74（P=0．001）。FibroScan诊断肝纤维化F1～F4、F2～F4、F3～F4、F4期的受试者工作特征曲线下面积分别为0．97、O．96、0．99、0．97。结论FibroScan诊断肝纤维化有较好的准确性。     

Feasibility of liver transient elastography with FibroScan® using a new probe for obese patients

Background & Aims: Liver stiffness measurement (LSM) failure when using transient elastography occurs in 2–10% of patients, and is generally related to obesity. The aim of this prospective study was to assess the feasibility of LSM when using a new XL probe on patients with a body mass index (BMI)≥30 kg/m². Methods: For each patient, LSM was performed using both M probe (currently available and dedicated to patients with standard morphology) and XL probe (dedicated to overweighed patients). A blood sample was taken to assess usual biological variables and simple readily available fibrosis blood tests. Results: Ninety‐nine patients were included (27 men, mean age 52 years, mean BMI 40.5 kg/m²). LSM was successful (10 valid measurements) in 45% of the cases with the M probe, vs 76% of the cases with the XL probe (P<0.001). Fifty‐nine percent of those who could not be measured (<10 valid measurements) using the M probe could successfully be measured using the XL probe. In the 44 patients successfully measured with both probes, LSM was correlated with the platelet count, prothrombin time, γ‐glutamyltransferase, aspartate aminotransferase, fasting glucose, AST platelet ratio index, Forns score and FIB‐4. Conclusion: The new XL probe allows providing a higher rate of LSM than the M probe in patients with an increased BMI and shows promising results for the evaluation of liver fibrosis.     

The effect of caffeine and alcohol consumption on liver fibrosis – a study of 1045 Asian hepatitis B patients using transient elastography

Background: Role of caffeine consumption in chronic hepatitis B virus (HBV)‐infected patients and the interaction with alcohol consumption is unclear. Aim: This study aimed to investigate the relationship between caffeine and alcohol consumption and liver stiffness in chronic HBV‐infected patients. Methods: Chronic HBV‐infected patients who underwent transient elastography examination in 2006–2008 were studied. Advanced fibrosis was defined as liver stiffness >9 kPa for patients with normal alanine aminotransferase (ALT) or >12 kPa for those with elevated ALT according to previous validation study. Caffeine and alcohol consumption was recorded using a standardized questionnaire. Excessive alcohol intake was defined as 30 g/day in men and 20 g/day in women. Results: The liver stiffness of 1045 patients who completed the questionnaire was 8.3 ± 6.2 kPa. Two hundred and sixteen (20.7%) patients had advanced fibrosis. Ninety‐five (19.0%) patients who drank ≥1 cup of coffee had advanced fibrosis, compared with 121 (22.2%) patients who drank <1 cup (P=0.21). The amount of caffeine intake had positive correlation with the amount of alcohol intake (r_s=0.167, P<0.001). Although 231 (22.1%) patients reported alcohol consumption, only 11 (1%) had excessive alcohol intake. The prevalence of advanced fibrosis among patients with mild to moderate alcohol intake (26, 18.8%) was comparable to that among non‐drinkers (190, 21.0%) (P=0.57). Conclusion: Caffeine intake does not affect liver stiffness in chronic HBV‐infected patients. Patients who drink coffee regularly tend to drink alcohol. Most chronic HBV‐infected patients do not have excessive alcohol consumption. The prevalence of advanced fibrosis among mild to moderate alcohol drinkers was low in this population.     

Interobserver discrepancy in liver fibrosis using transient elastography

Summary. Transient elastography is a useful method to assess liver fibrosis, but uncertainties still exist regarding reliability and reproducibility of the technique. We aimed to improve knowledge on interobserver variability with the procedure and tried to find factors associated with such variability. This was a cross‐sectional study to compare the results of transient elastography performed by two different operators, one test made just after the other. We assessed both results with correlation tests and with repeated parametric or nonparametric tests, as needed. We also carried out a multivariate analysis to find factors associated with discrepancy in the results obtained by the two operators. We included a total of 333 pairs of transient elastography tests, belonging to 274 different patients. A total of 325 pairs of tests (97.6%) were valid. Results of the first and the second tests were, respectively, median (and interquartile range) of direct measurement 6.2 (4.6–10.6) and 6.0 (4.4–10.1) kPa (P = 0.012), and mean ± standard deviation of log₁₀ of direct measurement 0.892 ± 0.316 and 0.871 ± 0.324 (P = 0.001). In 87 pairs of tests (26.7%), a discrepancy of at least 2 kPa between both results was found, and in 15 pairs of tests (4.6%), a discrepancy of at least 10 kPa was found. Discordance of at least one stage between both measurements was noted in 74 pairs of tests (22.8%). An association was found between higher stiffness and discrepancy between both operators (P < 0.001). Although transient elastography is a very convenient test to assess liver fibrosis in clinical practice, interobserver discrepancy in results is common and represents a significant problem with the technique. Discrepant results are more common in patients with higher values of stiffness.     

Assessment of liver stiffness in patients after living donor liver transplantation by transient elastography

Objective. Recurrence of hepatitis and progression of fibrosis are major problems in liver transplantation (LT) for patients with hepatitis C. Liver stiffness measurement (LSM) by transient elastography correlates well with histologic liver fibrosis stages in chronic liver diseases. The aim of this study was to evaluate the usefulness of transient elastography for the assessment of fibrosis in patients after living donor LT. Material and methods. Seventy-nine patients who visited our institution, and in whom LSM was successfully evaluated, were enrolled in the study. The patients were divided into three groups according to positivity for hepatitis C antibody and hepatitis B surface antigen as the hepatitis C virus (HCV) group (n=37), the hepatitis B virus (HBV) group (n=10), and the NBNC (negative for both hepatitis B and C) group (n=32). The correlation between LSM and histologic fibrosis stage was assessed in 36 patients. LSM was also compared with regard to the effect of interferon therapy in HCV patients. Results. The median value for liver stiffness was 6.8 kPa and the median time from LT was 3.1 years. In patients who underwent liver biopsy, stiffness was significantly correlated with the stages of fibrosis (p<0.001, rho = 0.848). In patients who received interferon therapy after LT, the LSM decreased over time in those with a sustained virological response, whereas LSM increased in patients without a response. Conclusion. Transient elastography may be an appropriate non-invasive procedure to sequentially assess the progression of liver fibrosis in patients after LT.     

Applicability and accuracy improvement of transient elastography using the M and XL probes by experienced operators

Transient elastography (TE) is the reference method to obtain liver stiffness measurements (LSM), but no results are obtained in 3.1% and unreliable in 15.8%. We assessed the applicability and diagnostic accuracy of TE re‐evaluation using M and XL probes. From March 2011 to April 2012 868 LSM were performed with the M probe by trained operators (50–500 studies) (LSM1). Measurements were categorized as inadequate (no values or ratio <60% and/or IQR/LSM >30%) or adequate. Inadequate LSM1 were re‐evaluated by experienced operators (>500 explorations) (LSM2) and inadequate LSM2 using XL probe (LSMXL). Inadequate LSM1 were obtained in 187 (21.5%) patients, IQR/LSM >30% in 97 (51%), ratio <60% in 24 (13%) and TE failed to obtain a measurement in 67 (36%). LSM2 achieved adequate registers in 123 (70%) of 175 registers previously considered as inadequate. Independent variables (OR, 95%CI) related to inadequate LSM1 were body mass index (1.11, 1.04–1.18), abdominal circumference (1.03, 1.01–1.06) and age (1.03, 1.01–1.04) and to inadequate LSM2 were skin‐capsule distance (1.21, 1.09–1.34) and abdominal circumference (1.05, 1.01–1.10). The diagnostic accuracy (AUROC) to identify significant fibrosis improved from 0.89 (LSM1) to 0.91 (LSM2) (P = 0.046) in 334 patients with liver biopsy or clinically significant portal hypertension. A third evaluation (LSMXL) obtained adequate registers in 41 (93%) of 44 patients with inadequate LSM2. Operator experience increases the applicability and diagnostic accuracy of TE. The XL probe may be recommended for patients with inadequate values obtained by experienced operators using the M probe. http://clinicaltrials.gov (NCT01900808).     

Liver stiffness measurement using transient elastography and hepatocellular carcinoma

Liver fibrosis has been gaining noticeable attention because it may lead to end-stage liver cirrhosis and ultimately to hepatocellular carcinoma. Thus, a precise estimation of the degree of liver fibrosis is crucial for predicting prognosis and deciding management of patients with chronic liver diseases. Many non-invasive approaches for the evaluation of liver fibrosis have been developed. Among these procedures, transient elastography has recently drawn great attention. Transient elastography has been reported to be well correlated with the degree of liver fibrosis by many investigators and various institutions. Since the degree of liver fibrosis is considered as a strong predictor of risk for hepatocellular carcinoma development, several trials have been performed to verify the usefulness of measurement of liver stiffness to predict the emergence of hepatocellular carcinoma. From these studies, transient elastography seems to be a promising procedure to predict the risk of hepatocellular carcinoma; however, further cohorts with long-term monitoring of liver stiffness are needed to confirm the usefulness of this method.