RESUMEN
BACKGROUND AND RATIONALE: Insulin resistance (IR), adipocytokines, oxidative stress and hepatic apoptosis play a pathogenetic role in nonalcoholic fatty liver disease (NAFLD). AIMS: The evaluation of specific adipocytokines and markers of IR, oxidative stress and apoptosis in NAFLD patients; the introduction of a combined non-invasive index for nonalcoholic steatohepatitis (NASH). MATERIAL AND METHODS: Thirty patients with biopsy-proven NAFLD (15 with simple nonalcoholic fatty liver [NAFL], 15 with NASH) and 24 controls were recruited. Blood samples for total and high molecular weight (HMW) adiponectin, visfatin and tumor necrosis factor (TNF)-α, the apoptotic by-product cytokeratin (CK)-18, the reactive oxygen metabolites (ROMs) and standard biochemical tests were measured. Homeostatic model of assessment - insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI) were calculated. MAIN RESULTS: Total and HMW adiponectin were significantly lower and TNF-α higher in either NAFL or NASH group compared to control group; CK-18 was significantly higher in NASH compared to either NAFL or control group. CHAI (an acronym of CK-18, HOMA-IR, AST Index) was calculated as the product of parameters being significantly different between NAFL and NASH groups. CHAI was significantly higher in NASH (24.2 [15.1-214.0]) compared to either NAFL (15.7 [6.8-22.7]) or control (5.1 [2.4-7.6]) group (p < 0.001) and significantly higher as the severity of steatosis, fibrosis, ballooning, lobular and portal inflammation advanced. CONCLUSION: CHAI was escalating from controls to NAFL and NASH and was higher by increasing the severity of all the main histological lesions. However, a validation study is needed before introducing CHAI in clinical practice.