胃腸および消化器系

抽象的な

A Caution in the use of the NAFIC Scoring System as a Diagnostic Screening Tool for Nonalcoholic Steatohepatitis

Akinobu Nakamura, Masato Yoneda, Yoshio Sumida, Hideaki Miyoshi, Atsushi Nakajima, Tatsuya Atsumi and Yasuo Terauchi

Objective: We reinvestigated the clinical usefulness of the NAFIC and modified NAFIC scoring systems in Japanese patients with nonalcoholic fatty liver disease (NAFLD) according to the presence/absence of obesity. Methods: A total of 141 Japanese patients with liver-biopsy-confirmed NAFLD were enrolled. All patients were classified as having nonalcoholic fatty liver (NAFL) or nonalcoholic steatohepatitis (NASH) on the basis of Matteoni’s classification. Obesity was defined as a body mass index of ≥25. To evaluate the overall accuracy of the NAFIC and modified NAFIC scoring systems, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of these scoring systems for the diagnosis of NASH were calculated. Results: In the obese group, the sensitivity, specificity, PPV and NPV of the NAFIC scoring system for the diagnosis of NASH were 67.3%, 76.2%, 77.8% and 65.3%, respectively, while the corresponding values for the modified NAFIC scoring systems were 78.8%, 69.0%, 75.9% and 72.5%. On the other hand, in the nonobese group, the sensitivity, specificity, PPV and NPV of the NAFIC scoring system were 47.1%, 86.7%, 66.7% and 74.3%, respectively, while those of the modified NAFIC scoring system were 58.8%, 83.3%, 66.7% and 78.1%, respectively. When the patients were divided by sex, the sensitivity of the NAFIC and modified NAFIC scoring systems in the female nonobese group were 53.8% and 69.2%, respectively. However, surprisingly, in the male nonobese group, the sensitivity of both the scoring systems was only 25.0%. Conclusion: The sensitivity of both the NAFIC and modified NAFIC scoring systems for the diagnosis of NASH was lower in the male nonobese group than in all the other groups. These findings suggest that caution should be exercised in the use of the NAFIC scoring system as a diagnostic screening tool for NASH in Japanese patients with NAFLD, especially male nonobese patients.