RESUMO
BACKGROUND: Obesity is a multifactorial disease characterized by fat accumulation, usually associated with non-alcoholic fatty liver disease, which can lead to advanced fibrosis or even cirrhosis. Bariatric surgery (BS) is a treatment approved for weight loss in morbidly obese patients. However, complications from this modality of treatment have been reported and liver cirrhosis connotes more risk procedure. AIMS: Evaluate non-invasive methods transient elastography (THE) and scores to establish the degree of liver fibrosis in patients submitted to BS, comparing their performance with liver histology. METHODS: We calculated liver fibrosis by non-invasive scores AST to platelet ration index (APRI), fibrosis-4 (FIB-4) and non-alcoholic fatty liver disease (NAFLD) score and THE before and 6 months after the bariatric surgery. The results were compared to liver histology. RESULTS: We included 85 patients, 69.4% females, with a mean age of 36 years, with a mean body mass index (BMI) of 41 kg/m2. The non-invasive scores were able to exclude clinically significant fibrosis in 85.9% (APRI) and advanced fibrosis in 96.5% (FIB-4) and 51.8% (NAFLD score). When comparing with the histological findings, the correlation with elastography was 45.9% for the same degree of fibrosis, with high negative predictive value (94.4%) in pre-surgical analysis. In the post-surgical analysis, the correlation with histology was 69.4% for THE and the negative predictive value to exclude clinically significant fibrosis was 98.5%. CONCLUSION: THE showed low correlation with histology in the pre-surgical analysis. All the methods had better results in post bariatric evaluation comparing with pre-bariatric data and the non-invasive FIB-4 score showed the best of them.
