Can nonalcoholic steatohepatitis be diagnosed without liver biopsy?

Discrimination of Nonalcoholic Steatohepatitis Using Transient Elastography in Patients with Nonalcoholic Fatty Liver Disease

Background/aims

The accuracy of noninvasive markers to discriminate nonalcoholic steatohepatitis (NASH) is unsatisfactory. We investigated whether transient elastography (TE) could discriminate patients with NASH from those with nonalcoholic fatty liver disease (NAFLD).

Methods

The patients suspected of NAFLD who underwent liver biopsy and concomitant TE were recruited from five tertiary centers between November 2011 and December 2013.

Results

The study population (n = 183) exhibited a mean age of 40.6 years and male predominance (n = 111, 60.7%). Of the study participants, 89 (48.6%) had non-NASH and 94 (51.4%) had NASH. The controlled attenuation parameter (CAP) and liver stiffness (LS) were significantly correlated with the degrees of steatosis (r = 0.656, P<0.001) and fibrosis (r = 0.714, P<0.001), respectively. The optimal cut-off values for steatosis were 247 dB/m for S1, 280 dB/m for S2, and 300 dB/m for S3. Based on the independent predictors derived from multivariate analysis [P = 0.044, odds ratio (OR) 4.133, 95% confidence interval (CI) 1.037–16.470 for CAP>250 dB/m; P = 0.013, OR 3.399, 95% CI 1.295–8.291 for LS>7.0 kPa; and P<0.001, OR 7.557, 95% CI 2.997–19.059 for Alanine aminotransferase>60 IU/L], we developed a novel CLA model for discriminating patients with NASH. The CLA model showed good discriminatory capability, with an area under the receiver operating characteristic curve (AUROC) of 0.812 (95% CI 0.724–0.880). To assess discriminatory power, the AUROCs, as determined by the bootstrap method, remained largely unchanged between iterations, with an average value of 0.833 (95% CI 0.740–0.893).

Conclusion

This novel TE-based CLA model showed acceptable accuracy in discriminating NASH from simple steatosis. However, further studies are required for external validation.

The Wide and Complex Field of NAFLD Biomarker Research: Trends

Background. Nonalcoholic fatty liver disease is now acknowledged as a complex public health issue linked to sedentary lifestyle, obesity, and related disorders like type 2 diabetes and metabolic syndrome. Aims. We aimed to retrieve its trends out of the huge amount of published data. Therefore, we conducted an extensive literature search to identify possible biomarker and/or biomarker combinations by retrospectively assessing and evaluating common and novel biomarkers to predict progression and prognosis of obesity related liver diseases. Methodology. We analyzed finally 62 articles accounting for 157 cohorts and 45,288 subjects. Results. Despite the various approaches, most cohorts were considerably small and rarely comparable. Also, we found that the same standard parameters were measured rather than novel biomarkers. Diagnostics approaches appeared incomparable. Conclusions. Further collaborative investigations on harmonizing ways of data acquisition and identifying such biomarkers for clinical use are necessary to yield sufficient significant results of potential biomarkers.

The Fatty Liver Index has limited utility for the detection and quantification of hepatic steatosis in obese patients

PURPOSE

Noninvasive tools for the detection of hepatic steatosis are needed. The Fatty Liver Index (FLI), which includes body mass index (BMI), waist circumference, triglycerides, and γ-glutamyl-transferase, has been proposed as a screening tool for fatty liver. Our objective was to validate the FLI for the detection and quantification of hepatic steatosis in an obese population.

METHODS

Patients with chronic liver disease and BMI ≥ 28 kg/m(2) underwent liver biopsy and FLI determination. FLI performance for diagnosing steatosis compared with biopsy was assessed using areas under receiver operating characteristic curves (AUROCs), and a novel model for the prediction of significant steatosis (≥5 %) was derived.

RESULTS

Among 250 included patients, 65 % were male, and the median BMI was 33 kg/m(2); 48 % had nonalcoholic fatty liver disease, and 77 % had significant (≥5 %) steatosis. The FLI was weakly correlated with the percentage (ρ = 0.25, p = 0.0001) and grade of steatosis (ρ = 0.28, p < 0.00005). The median FLI was higher among patients with significant steatosis (91 vs. 80 with <5 % steatosis; p = 0.0001) and the AUROC for this outcome was 0.67 (95 % CI 0.59-0.76). At an optimal FLI cut-off of 79, the FLI was 81 % sensitive and 49 % specific, and had positive and negative predictive values of 84 and 43 %, respectively. A novel index including triglycerides, glucose, alkaline phosphatase, and BMI outperformed the FLI for predicting significant steatosis [AUROCs 0.78 vs. 0.68; p = 0.009 (n = 247)].

CONCLUSIONS

In obese patients, the FLI is a poor predictor of significant steatosis and has limited utility for steatosis quantification compared with liver histology. A novel index including triglycerides, glucose, alkaline phosphatase, and BMI may be useful, but requires validation.