Evaluation and improvement of a reliable diagnosis of cirrhosis by blood tests.
ABSTRACT To evaluate the rates of reliable diagnosis of cirrhosis by two usual blood tests.
Reliable diagnosis was mainly evaluated by comparing rates of positive (PPV) and negative (NPV) predictive values with FibroTest and FibroMeters, as either standard test or specifically designed for cirrhosis, in 1056 patients with chronic hepatitis C.
Using the diagnostic limits provided by fibrosis stage scales, the PPV for cirrhosis was: standard FibroMeters: 68.5% versus FibroTest: 37.1%. Using 95% PPV, the cirrhosis detection rate was: specific FibroMeter: 26.1% versus FibroTest: 2.0% (P<10(-3)). The cirrhosis detection rate increased from 26 to 65% by performing liver biopsy in 8% of patients with indeterminate results on specific FibroMeter between 95% NPV and PPV. On the other hand, specific FibroMeter provided three intervals of 95% reliable diagnosis with no biopsy: less than or equal to 95% NPV: no cirrhosis (threshold: diagnosis); significant fibrosis; and greater than or equal to 95% PPV: cirrhosis.
The detection rate and PPV for cirrhosis using fibrosis scales were fair for standard FibroMeter and poor for FibroTest. Around one-fourth of cases of cirrhosis are detected by the 95% PPV of specific FibroMeter, and around two-thirds by performing an additional liver biopsy in only 8% of patients. Finally, specific FibroMeter can avoid liver biopsy by classifying patients into three categories: no cirrhosis; significant fibrosis; and cirrhosis.
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ABSTRACT: Liver fibrosis is mainly evaluated by qualitative histological examination. Although histological semi-quantitative scores and quantitative determination with image analysis are now possible, these methods have not been fully validated and compared. Therefore, we evaluated these two methods prospectively in 243 patients with chronic liver disease. The semi-quantitative fibrosis score was evaluated by two independent pathologists, using the Knodell fibrosis score and a 6-grade score derived from the Metavir score; the area of fibrosis was measured by image analysis. The serum levels of hyaluronate, N-terminal peptide of procollagen III, laminin, transforming growth factor-beta1, alpha2-macroglobulin, apolipoprotein A1, PGA score and prothrombin index were measured. There was a good correlation between the semi-quantitative fibrosis score and the area of fibrosis (r=0.84, p<10(-4)). Using multiple regression analysis, the semi-quantitative score was predicted by the 8 serum markers with R2=0.69 (R2=0.59 for hyaluronate at the 1st step) while the area of fibrosis was predicted with R2=0.79 (R2=0.76 for hyaluronate at the 1st step), and the Knodell fibrosis score was predicted with R2=0.65 (R2=0.31 for hyaluronate at the 1st step). The area of fibrosis, as determined by image analysis, and the semi-quantitative score are well correlated. However, for serum markers the correlation is higher with the area of fibrosis than with the semi-quantitative score. Other characteristics such as reproducibility, rapidity, simplicity, adaptability, and exhaustiveness also favor image analysis.Journal of Hepatology 03/1998; 28(3):439-46. · 9.86 Impact Factor
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ABSTRACT: The objective was to develop new blood tests to characterize different fibrosis parameters in viral and alcoholic chronic liver diseases. Measurements included 51 blood markers and Fibrotest, Fibrospect, ELFG, APRI, and Forns scores. The clinically significant fibrosis was evaluated via Metavir staging (F2-F4), and image analysis was used to determine the area of fibrosis. In an exploratory step in 383 patients with viral hepatitis, the area under the receiving operator characteristic (AUROC) curve for stages F2-F4 in a test termed the "Fibrometer" test combining platelets, prothrombin index, aspartate aminotransferase, alpha2-macroglobulin (A2M), hyaluronate, urea, and age was 0.883 compared with 0.808 for the Fibrotest (P = .01), 0.820 for the Forns test (P = .005), and 0.794 for the APRI test (P < 10(-4)). The Fibrometer AUROC curve was 0.892 in the validating step in 120 patients. The AUROC curve for stages F2-F4 in a test combining prothrombin index, A2M, hyaluronate, and age was 0.962 in 95 patients with alcoholic liver diseases. The area of fibrosis was estimated in viral hepatitis by testing for hyaluronate, gamma-glutamyltransferase, bilirubin, platelets, and apolipoprotein A1 ((a)R(2) = 0.645), and in alcoholic liver diseases by testing for hyaluronate, prothrombin index, A2M, and platelets ((a)R(2) = 0.836). In conclusion, the pathological staging and area of liver fibrosis can be estimated using different combinations of blood markers in viral and alcoholic liver diseases. Whereas the Fibrometer has a high diagnostic accuracy for clinically significant fibrosis, blood tests for the area of liver fibrosis provide a quantitative estimation of the amount of fibrosis, which is especially useful in cirrhosis.Hepatology 12/2005; 42(6):1373-81. · 12.00 Impact Factor
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ABSTRACT: Inter-observer agreement on activity and fibrosis scores used in chronic viral hepatitis has only been studied under selected conditions. The aim of this study was to identify the sources of variability due to specimen characteristics and observers. This study included 254 liver specimens and 15 pathologists and used the Metavir score. In 44 specimens scored by 4 academic pathologists, agreement of Metavir score was good overall, but better for fibrosis (kappa = 0.59) than for activity (kappa = 0.43) and poor for lobular necrosis (kappa = 0.15). The mean agreement was better for senior (0.60 +/- 0.24) than junior pathologists (0.52 +/- 0.30, P < .05). Mean intrabserver agreement was better than inter-observer agreement (0.77 +/- 0.18 vs. 0.58 +/- 0.26, P < .01). In 157 specimens scored by 2 expert pathologists (one senior, one junior), agreement of Metavir score was only good but greatly improved after consensus reading (fibrosis: kappa = 0.48 and 0.77, activity: kappa = 0.44 and 0.70, respectively, before and after consensus). Several causes of disagreement were identified: specimen length, fibrosis class number, observer bias, and putative causes related to Metavir score or specimen. In an intercenter evaluation involving 59 specimens, 1 expert and 10 nonacademic pathologists, agreement was very poor and did not improve over 5 years for activity (kappa = 0.22-0.25) or fibrosis (kappa = 0.13-0.18). In conclusion, the level of experience (specialization, duration, and location of practice) has more influence on agreement than the characteristics of the specimen (length, fibrosis class number, miscellaneous factors). Agreement can be improved by experienced pathologist or consensus reading.Hepatology 03/2005; 41(2):257-64. · 12.00 Impact Factor