Review
Copyright ©The Author(s) 2017.
World J Gastroenterol. Sep 28, 2017; 23(36): 6571-6592
Published online Sep 28, 2017. doi: 10.3748/wjg.v23.i36.6571
Table 1 Main features and differences between Nonalcoholic Steatohepatitis Activity score and Steatosis, Activity, and Fibrosis score
NASSAF
Scoring systemSteatosis + Lobular Inflammation + Ballooning: 0-8Steatosis, Activity (Lobular Inflammation + Ballooning), Fibrosis: S0-3, A0-4, F0-4
Details of scoringSteatosisSteatosis
0: < 5%0: < 5%
1: 5%-33%1: 5%-33%
2: 34%-66%2: 34%-66%
3: > 67%3: > 67%
Lobular inflammationLobular inflammation
0:000:00
1: < 2/20X1: < 2/20X
2: 2-4/20X2: ≥ 2/20X
3: > 4/20X
Ballooning (number of ballooned hepatocytes)Ballooning (size and shape of hepatocytes)
0: None0: normal hepatocytes
1: Few1: clusters, reticulated cytoplasm
2: Many2: enlarged hepatocytes
Fibrosis stageFibrosis stage
F0: NoneF0: 0
F1a: zone 3 perisinusoidal, delicateF1: zone 3 perisinusoidal (all), or portal only
F1b: perisinusoidal, denseF2: zone 3 + portal
F1c: portal onlyF3: bridging
F2: 1a or 1b + portalF4: cirrhosis
F3: bridging
F4: cirrhosis