Marsha is a 53 year old female whom you know well and is your patient for the last 10 years. You are following up with her after receiving lab results showing an AST of 39 IU/L and ALT 45 IU/L respectively. Bilirubin and alkaline phosphatase were normal. You had checked these labs as part of your yearly evaluation for use of statin. The patient is a type 2 diabetic but is controlled on metformin with last HgB A1c of 6.8. Her BMI is 33 kg/m2, platelets are 200 x10⁹/µL, and albumin is 4.0 g/dL. You were out on vacation last week and your partner ordered a RUQ ultrasound on Marsha which showed steatosis. You recall that Marsha told you at the last visit that she drinks 1 glass of wine about every 2 weeks and never binge drinks. She does not have a history of alcohol overuse. Calculate Marsha’s NAFLD-FS and decide would you proceed to evaluate Marsha’s elevated AST/ALT?
This case illustrates the use of the NAFLD-FS and algorithm in this clinical toolkit. Her calculated NAFLD-FS is 0.14 which places her in the indeterminate range. Therefore, she will need to be referred to a gastroenterologist or hepatologist where a Fibroscan will be used to evaluate potential for advanced fibrosis further. If her fibroscan is greater than 7.0 kpa, she would likely need a liver biopsy. If it was below 7.0 kpa, she would likely be monitored with serial fibroscan/NAFLD-FS by the specialist. Of note, we need to check a hepatitis panel on Marsha to rule out viral hepatitis. This is especially true since Marsha was born in 1965 and the CDC guidelines note an increased change of Hepatitis C in patients born between 1945 and 1965. Her AUDIT-C score is 2 which argues against concern for alcoholic steatosis/steatohepatitis. If there is any doubt whether this is alcoholic versus non-alcoholic fatty liver disease, an ANI (click for link to calculator) can be calculated. It is also reasonable to exclude other differentials with the below labs
- ceruloplasmin
- ANA, IgG, & Antismooth muscle antibodies to rule out Autoimmune hepatitis
- anti mitochondrial antibody to rule out Primary biliary cholangitis
- alpha-1 antitrypsin to rule out alpha-1 antitrypsin deficiency
- IgA and tissue transglutaminase antibody to rule out celiac disease