FIB-4 With Reflex to NASH FibroSure® Plus

Serum and whole blood

Serum: 4 mL divided into two tubes, 0.5 mL for initial testing and 3.5 mL for possible reflex

Whole blood: tube filled to capacity

Serum: 3 mL divided into two tubes, 0.5 mL for initial testing and 2.5 mL for possible reflex

Whole blood: tube filled to capacity

Gel-barrier tube or red-top tube and lavender-top (EDTA) tube

Patient should be fasting for at least eight hours.

FIB-4 index is reported to be a simple, accurate, non-invasive and readily available laboratory test index that can help in evaluation of patients with HCV and Non-Alcoholic Fatty Liver Disease (NAFLD), now known as metabolic dysfunction-associated steatotic liver disease (MASLD), for the presence of liver fibrosis indication for liver biopsy, and other liver-related complications.

Clumping may cause false low platelet count. Platelet satellitism around neutrophils will cause a pseudothrombocytopenia. RBC or WBC fragments including fragmented fragile leukemic cells and neutrophil pseudoplatelets may cause falsely elevated counts. NASH FibroSure® Plus is recommended for patients with suspected nonalcoholic fatty liver disease, now known as metabolic dysfunction-associated steatotic liver disease (MASLD). It is not recommended for patients with other liver diseases. It is also not recommended in patients with Gilbert disease, acute hemolysis, acute hepatitis, acute inflammation of the liver, autoimmune hepatitis, extrahepatic cholestasis, transplant patients, and/or renal insufficiency patients. Any of these clinical situations may lead to inaccurate quantitative predictions of fibrosis.

This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration. The FDA has determined that such clearance or approval is not necessary.

See individual test components.

FIB-4 index is calculated first; if FIB-4 index value is between 0 and 1.29, testing stops; if FIB-4 index value is greater than 1.29, testing is reflexed to NASH FibroSure® Plus at an additional cost.

NASH FibroSure® Plus test is a noninvasive assessment of liver status in patients with nonalcoholic fatty liver disease (NAFLD). Quantitative results of 10 biochemicals in combination with age and gender are analyzed using a computational algorithm to provide a quantitative surrogate marker (0.0-1.0) of liver fibrosis (Metavir F0-F4), hepatic steatosis (0.0-1.0, S0-S3), and nonalcoholic steatohepatitis (NASH) (0.0-0.75, N0-N2). The absence of steatosis (S<0.41) precludes the diagnosis of NASH, now known as metabolic dysfunction-associated steatohepatitis (MASH).

The FIB-4 index value is calculated using the 4 parameters formula: FIB-4 = [Age(Years) x AST(IU/L)]/[Platelets(10E3/L) x ALT^.5 (IU/L)]