Validation and Performance of FibroScan®-AST (FAST) Score on a Brazilian Population with Nonalcoholic Fatty Liver Disease.

BACKGROUND AND AIM: FAST score has a good performance for diagnosing the composite of NASH + NAS ≥ 4 + F ≥ 2. However, it has not been evaluated in Latin American individuals with nonalcoholic fatty liver disease (NAFLD). We aimed to analyze the performance of the FAST score in a Brazilian NAFLD population. METHODS: Cross-sectional study was held in ≥ 18 years NAFLD patients diagnosed by ultrasonography and submitted to liver biopsy (LB). Liver stiffness (LSM) and CAP measurements were performed with FibroScan®, using M (BMI < 32 kg/m2) or XL probes. Area under receiver operating characteristic (AUROC) curves were calculated as well as sensitivity (S), specificity (Spe), positive predictive value (VPP) and negative predictive value (NPV) for the previously established FAST score cut-offs. RESULTS: Among 287 patients included (75% female; mean age 55 ± 10 years), NASH + NAS ≥ 4 + F ≥ 2 was reported in 30% of LB. For the FAST cut-off of 0.35, the S and NPV to rule out NASH + NAS ≥ 4 + F ≥ 2 were 78.8% and 87.8%, respectively. Regarding the cut-off of 0.67, the Spe and PPV to rule-in NASH + NAS ≥ 4 + F ≥ 2 were 89.1%, 61.8%, respectively. The AUROC of FAST for all included patients was 0.78 (95% CI 0.72-0.84) and for those with ≥ 32 kg/m2 was 0.81 (95% CI 0.74-0.88). CONCLUSION: FAST score has a good performance in a Brazilian NAFLD population, even in patients with higher BMI when the XL probe is adopted. Therefore, FAST can be used as a noninvasive screening tool mainly for excluding the diagnosis of progressive NASH, reducing the number of unnecessary liver biopsies.

Evaluation of thrombocytopenia in patients with non-alcoholic fatty liver disease without cirrhosis.

INTRODUCTION AND OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disorder in western countries. It is often related to metabolic syndrome, presenting an increased risk of advanced liver disease and cardiovascular-related death. In some etiologies of chronic liver disease, thrombocytopenia has been associated not only with advanced stages of fibrosis but also with autoimmune disease. In NAFLD, however, its prevalence and related factors are still unknown. The aim of this study is to evaluate the prevalence of thrombocytopenia in NAFLD patients without cirrhosis and to investigate its related risk factors. PATIENTS AND METHODS: This was a retrospective study carried out in two tertiary hospitals in the South and Southeast regions of Brazil. Patients diagnosed with NAFLD by liver biopsy were included. Those with other causes of liver disease and/or cirrhosis were excluded. For analysis, patients were divided into two groups, with and without thrombocytopenia. Data was analyzed using a significance level of 5%. RESULTS: 441 non-cirrhotic patients with NAFLD (evaluated by liver biopsy) were included in the study. The prevalence of thrombocytopenia was 3.2% (14/441 patients). In the comparative analysis between groups, thrombocytopenia was associated with male sex (p=0.007) and level of hemoglobin (p=0.023). CONCLUSION: Thrombocytopenia is an infrequent event in NAFLD patients without cirrhosis and is related with male sex and higher hemoglobin levels.

Transient hepatic elastography has the best performance to evaluate liver fibrosis in non-alcoholic fatty liver disease (NAFLD).

INTRODUCTION AND AIM: The gold-standard for fibrosis diagnosis in non-alcoholic fatty liver disease (NAFLD) is liver biopsy, despite its invasive approach, sampling limitations and variability among observers. The objective was to validate the performance of non-invasive methods (Fibroscan™; APRI, FIB4 and NAFLD score) comparing with liver biopsy in the evaluation of liver fibrosis in patients with NAFLD. MATERIAL AND METHODS: NAFLD patients ≥18 years of age who were submitted to liver biopsy were included and evaluated at two reference tertiary hospitals in Brazil with transient hepatic elastography (THE) assessment through Fibroscan™, APRI, FIB4 and NAFLD scores were determined. Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values for the diagnosis of advanced fibrosis were calculated to evaluate the performance of these non-invasive methods in NAFLD patients, adopting liver biopsy as the gold standard. RESULTS: A total of 104 patients were studied. At three different cutoff values (7.9, 8.7 and 9.6kPa) THE presented the highest sensitivity values (95%, 90% and 85% respectively), and the highest NPV (98%, 96.4% and 95.1% respectively) for the diagnosis of advanced fibrosis. It also presented the highest AUROC (0.87; CI 95% 0.78-0.97). CONCLUSION: When compared to the gold standard, transient hepatic elastography presented the best performance for the diagnosis and exclusion of advanced fibrosis in patients with NAFLD, overcoming APRI, FIB4 and NAFLD score.

The performance of M and XL probes of FibroScan for the diagnosis of steatosis and fibrosis on a Brazilian nonalcoholic fatty liver disease cohort.

OBJECTIVES: Recently, controlled attenuation parameter (CAP) was incorporated for XL probe. However, its performance through M and XL probes has been scarcely evaluated in nonalcoholic fatty liver disease (NAFLD). The performance of probes regarding transient elastography by Fibroscan is still under debate. AIM: Compare the performance of CAP and transient elastography in NAFLD patients obtained through XL with M probes using histological analysis as gold standard. METHODS: NAFLD patients underwent liver biopsy and FibroScan/CAP with M and XL probes the same day. C-statistic evaluated CAP performance in the identification of moderate/severe (≥33%) and severe (≥66%) steatosis by both probes and transient elastography performance for identification of significant fibrosis (≥F2). RESULTS: Eighty-one patients (74% female; age 54.2 ± 9.9 years; BMI 32.8 ± 5.2/ BMI ≥ 25 92.6%; 96% metabolic syndrome; 60% diabetes mellitus) were included. Mean CAP with M and XL probes was 314 ± 39 and 325 ± 47 dB/m, respectively. The areas under receiver operating characteristic curves (AUROCs) of the M and XL probes for steatosis detection ≥33% were 0.75 (0.64-0.84) and 0.76 (0.65-0.84) (P = 0.95) and for steatosis ≥66% 0.83 (0.73-0.90) and 0.82 (0.71-0.89) (P = 0.73), respectively, with similar performances for both degrees of steatosis. Regarding transient elastography, AUROCs of M and XL probes for ≥F2 were 0.82 (0.71-0.93) and 0.80 (0.69-0.92) (P = 0.66). CONCLUSION: Performance of M and XL probes is similar for the diagnosis of moderate and severe steatosis and significant fibrosis even on a overweight population with NAFLD.