The diagnosis of nonalcoholic steatohepatitis (NASH) is defined by the presence and pattern of specific histological abnormalities on liver biopsy. A separate system of scoring the features of nonalcoholic fatty liver disease (NA) called the NAFLD Activity Score (NAS) was developed as a tool to measure changes in NAFLD during therapeutic trials. However, some studies have used threshold values of the NAS, specifically NAS ≥ 5, as a surrogate for the histologic diagnosis of NASH. To evaluate whether this unintended use of the NAS is valid, biopsy and clinical data from the 976 adults in NASH CRN studies were reviewed. Biopsies were evaluated centrally by the NASH CRN Pathology Committee. Definite steatohepatitis (SH) was diagnosed in 58.1%, borderline SH in 19.5% and “not SH” in 22%. The NAS was ≥ 5 in 50% and ≤ 4 in 49%; in this cohort only 75% of biopsies with definite SH had a NAS ≥ 5, while 28% of borderline SH and 7% of "not SH" biopsies had NAS ≥ 5. Of biopsies with a NAS ≥ 5, 86% had SH and 3% "not SH". NAS ≤ 4 did not indicate benign histology; 29% had SH and only 42% had "not SH". Higher values of the NAS were associated with higher levels of ALT and AST, while the diagnosis of SH was associated with features of the metabolic syndrome. Conclusions The diagnosis of definite SH or the absence of SH based on evaluation of patterns as well as individual lesions on liver biopsies does not always correlate with threshold values of the semiquantitative NAS. Clinical trials and observational studies should take these different performance characteristics into account.

No abstract

Serum ferritin (SF) levels are commonly elevated in patients with nonalcoholic fatty liver disease (NAFLD), due to systemic inflammation, increased iron stores or both. The aim of this study was to examine the relationship between elevated SF and NAFLD severity. Demographic, clinical, histologic, laboratory and anthropometric data were analyzed in 628 adult patients with NAFLD (age≥18 years) with biopsy-proven NAFLD and a serum ferritin measurement within six months of their liver biopsy. A threshold SF>1.5XULN (i.e. >300 ng/ml in women and >450 ng/ml in men) was significantly associated with male sex, elevated serum ALT, AST, iron, transferrin-iron saturation, iron stain grade and decreased platelets (p<0.01). Histologic features of NAFLD were more severe among patients with SF>1.5XULN including steatosis, fibrosis, hepatocellular ballooning and diagnosis of NASH (p<0.026). On multiple regression analysis, SF>1.5XULN was independently associated with advanced hepatic fibrosis (OR, 1.66, 95% CI, 1.05-2.62, p=0.028) and increased NAFLD Activity Score (NAS) (OR, 1.99, 95% CI, 1.06-3.75, p=0.033). Conclusions A SF >1.5XULN is associated with hepatic iron deposition, a diagnosis of NASH, and worsened histologic activity, and is an independent predictor of advanced hepatic fibrosis among patients with NAFLD. Furthermore, elevated SF is independently associated with higher NAS even among patients without hepatic iron deposition. We conclude that serum ferritin is useful to identify NAFLD patients at risk for NASH and advanced fibrosis.

Adult nonalcoholic fatty liver disease (NAFLD) is characterized by absent or mild portal chronic inflammation (CI); in children, portal CI may be predominant. This study correlated clinical features with portal CI. Centrally-graded biopsies and temporally-related clinical parameters from 728 adults and 205 children. From the Nonalcoholic Steatohepatitis Clinical Research Network (NASH CRN) were evaluated. Mild, more than mild and no portal CI were found in 60%, 23% and 16% of adult biopsies and 76%, 14% and 10% of pediatric biopsies. Autoantibodies, and elevated alanine aminotransferase were not associated with portal CI. Clinical features associated with "more than mild" in adults were older age (P < 0.0001), female gender (P ‫؍‬ 0.001), higher body mass index (P < 0.0001), elevated insulin levels (P ‫؍‬ 0.001), higher homeostasis model assessment of insulin resistance score (HOMA-IR) (P < 0.0001), and medications used for NAFLD (P ‫؍‬ 0.0004), diabetes (P < 0.0001), and hypertension (P < 0.0001). "More than mild" in the pediatric biopsies correlated with younger age (P ‫؍‬ 0.01), but not with body mass index, insulin or HOMA-IR. In both groups, lobular and portal inflammation scores had no association, but there was an association with definite steatohepatitis (P < 0.0001). Features associated in the adult biopsies with "more than mild" were steatosis amount (P ‫؍‬ 0.01) and location (P < 0.0001), ballooning (P < 0.0001), and advanced fibrosis (P < 0.0001). In the pediatric biopsies, "more than mild" was associated with steatosis location (P ‫؍‬ 0.0008) and fibrosis score (P < 0.0001), specifically, the portal/periportal fibrosis or greater fibrosis) (P < 0.01). Conclusion: Increased portal CI is associated with many clinical and pathologic features of progressive NAFLD in both adults and children, but not with ALT, autoantibodies, or lobular inflammation. More than mild portal CI in liver biopsies of untreated NAFLD may be considered a marker of advanced disease. (HEPATOLOGY 2009;49:809-820.)