Which clinical and sonographic parameters may be useful to discriminate NASH from steatosis?

Background: The natural history of nonalcoholic steatohepatitis (NASH) includes the passage through steatosis.

Goal: To retrospectively evaluate the usefulness of sonographic parameters compared to histological diagnosis when differentiating steatosis from NASH.

Study: This retrospective study reviewed records of patients with steatosis from databases of our Departments, selecting only those who had been diagnosed by sonography and liver biopsy [64 males (63.82%); 30 females (36.18%)].

Results: Attenuation of the echo amplitude (P<0.05; odds ratio (OR): 3.43; confidence interval (CI): 1.02-11.57), focal fat sparing (P<0.05; OR: 3; CI: 1.02-11.88) and splenic diameter (P<0.05; OR: 1.66; CI: 1.04-3.26) were independent predictors of NASH. A significantly higher association of attenuation of the echo amplitude, enlarged splenic diameter, and presence of focal fat sparing was observed in NASH patients (P<0.01).

Conclusions: It is very difficult to build a predictive system to distinguish NASH from steatosis based on sonographic scores. However, it is already possible to differentiate NASH from steatosis by combining 3 simple sonographic parameters: attenuation of the echo amplitude, enlarged splenic diameter, and presence of focal fat sparing.