Diagnóstico de esteatosis hepática por métodos clínicos, bioquímicos y por imágenes

Non-alcoholic fatty liver disease (NAFLD) includes a spectrum of liver diseases ranging from steatosis to steatohepatitis, fibrosis and cirrhosis. Its prevalence increases with age and with obesity, and is strongly associated with the presence of metabolic syndrome and increased cardiovascular and malignant diseases. It is caused by an accumulation of triglycerides in liver hepatocytes and muscles, and related to insulin resistance. Its presence is associated with the increase of alanine aminotransferase (alt), although it may not be elevated in advanced disease. There are 5 indexes used for the diagnosis of hepatic steatosis: SteatoTest, fatty liver index, NAFLD liver fat score, lipid accumulation product and hepatic steatosis index, whereas for esteatohepatitis the NASH test, NASH diagnostics, as well as the non-alcoholic steatohepatitis (NASH) score and HAIR (hypertension, ALT, and insulin resistance). In stages of fibrosis AST-ALT index increases as well as ferritin in blood and the NAFLD fibrosis score, which has a high specificity for diagnosis. Abdominal ultrasound is widely available, but its diagnostic sensitivity is lower when there are mild degrees of hepatic fatty infiltration. Computed tomography has a specificity of 100% when fat content is greater than 30%, but the radiation emitted prevents frequent use. Magnetic resonance spectroscopy is the method of choice for the detection and quantification of liver fat content. Liver biopsy is an invasive method that enables appropriate prognostic classification of the disease, but has some complications, and should only be performed in selected individuals: high risk of steatohepatitis or fibrosis risk of laboratory or clinical or other co-existing liver disease. Early identification of NAFLD allows early measures to be implemented in order to reduce morbidity and mortality associated with this condition.