Positive Pattern Recognition System Using Alanine Aminotransferase, TypeIV Collagen 7S and E Value (Liver Stiffness) for the Diagnosis of Nonalcoholic Steatohepatitis Based on Natural History

Background: A simple diagnostic system for nonalcoholic fatty liver disease (NAFLD) instead of a biopsy is expected. We investigated the possibility of a positive pattern recognition system for evaluation of nonalcoholic fatty liver (NAFL) and the stages of nonalcoholic steatohepatitis (NASH). Methods: 68 Japanese patients with biopsy-proven NAFLD were enrolled. Serological biomarkers and markers obtained by medical imaging were investigated to explore candidates for diagnostic system. After selected markers were statistically evaluated, every patient was distributed in pattern combinations.Results: We selected three markers based on natural history and decided the critical values: alanine aminotransferase/ALT (persistent ≧ 45 IU/L) as hepatitis marker, type Ⅳ collagen 7S (≧ 5.1 ng/ml) as fibrosis one and E value (≧5.5 kPa) as stiffness one. After we statistically evaluated their accuracies, every patient was classified into their combination patterns. Major patterns were limited to four. Comparing relationships between histological classifications and positive patterns , the patients with NAFL were mainly distributed in pattern (ALT, type Ⅳ collagen , E value : -, -, -), those with NASH stage 0-1 in (+, -, +), those with NASH stage 2-3 in (+, +, +), and those with NASH stage 4 in (-, +, +).Conclusion: The positive patters changed with NAFL and NASH conditions. Our results showed a correlation between the positive patterns using three markers and histological results. Positive pattern recognition system based on natural history is useful in a differential diagnosis of NAFLD and for evaluation of the severity of fibrosis in patients with NASH.