Silent non-alcoholic fatty liver disease-a clinical-histological study

We studied the prevalence of non-alcoholic fatty liver disease and non-alcoholic-steatohepatitis in patients with metabolic-syndrome but normal liver enzymes. The histological findings of patients with normal liver enzymes and non-alcoholic-steatohepatitis were compared with those of a control-group with persistently abnormal liver enzymes.

Patients presenting with normal liver enzymes were enrolled in the study and underwent liver biopsy. Prevalence of non-alcoholic-steatohepatitis and risk factors for fibrosis and cirrhosis were evaluated. Data from a control-group with non-alcoholic-steatohepatitis and abnormal liver enzymes were used to compare the histological findings.

Fifty-eight of the 80 patients enrolled had varying degrees of non-alcoholic steatohepatitis, of these 26 had fibrosis and 8 silent cirrhosis. The association of metabolic-syndrome, female-sex, a long-history of obesity and body mass index>45 were considered to be independent risk-factors for fibrosis. Comparing the histological findings of cases and controls we found a similar severity of steatosis and fibrosis, with a greater prevalence of ballooning degeneration and glycogenated-nuclei rather than lobular-inflammation.

In the subjects selected according to our criteria, liver enzyme levels could not be used as surrogate markers of non-alcoholic-steatohepatitis. Histological hallmarks of patients with metabolic-syndrome, normal liver enzymes and non-alcoholic-steatohepatitis consist to a lesser degree of lobular-inflammation and a more severe ballooning and glycogenated-nuclei.