FOR THE METAVIR COOPERATIVE STUDY GROUP histological classification of chronic hepatitis, and several Histological activity reflects the global assessment of propositions have recently been made by different groups of basic necroinflammatory lesions and is a criterion of mapathologists. [4][5][6][7] A consensual proposition was to separately jor importance in chronic hepatitis C. The aim of this assess, using scoring systems, the degree of liver fibrosis and study was to propose and test the accuracy of a simple that of activity. 4,6 Liver fibrosis is simple to precisely define algorithm that generates a single activity score based and thus to reproducibly score. 8 In contrast, the grading of on basic pathological features. A panel of 10 pathologists activity, which integrates the different basic necroinflammareviewed 363 chronic hepatitis C liver biopsies and tory lesions, is more difficult to assess; morever, it is of imporgraded the activity of hepatitis according to their own tance in the decision of whether or not to treat patients in experience (reference activity). Then, a consensual algomany therapeutic trials. Although not proven, inflammation rithm on the grading of activity was established by the and liver cell necrosis are the hallmarks of active disease 10 experts in a panel discussion. Finally, stepwise disthat may predict evolution toward fibrosis and cirrhosis. criminant analysis was performed to define which basic Several approaches have been proposed to assess histologifeatures had been intuitively used in the reference activcal activity. One of them is the semiquantitative scoring sysity (statistical activity). To test the accuracy of the algotem of Knodell et al., in which fibrosis and portal, periportal, rithm, concordance between the activity defined by the and lobular necrotic and inflammatory components are asalgorithm and the reference activity was assessed. It was sessed separately and their coding values added. 10 The global compared with concordance between the activity descore appears accurate because it varies over large ranges, fined by the statistical model and the reference activity.but its value may be limited by poor reproducibility, because The algorithm proposed by the panel for the grading of each feature has its own observer variation. 8 Another possible activity included piecemeal necrosis and lobular necroapproach is to consider that periportal and intralobular nesis. Concordance between reference activity and activity croinflammatory lesions are related to the same pathogenic defined by the algorithm was substantial (305 cases, 84%, mechanism and that they must be globally assessed. As prek Å .75). Discriminant analysis showed that piecemeal viously reported, assessment of activity must be separated necrosis, lobular necrosis, and portal inflammation were from staging of fibrosis.4 independently used to grade the activity. Concordance The aim of this study was to propose a simple algorithm between reference activity and activity defined by the that generates a single sco...

No abstract

No abstract

No abstract