fib4 {cliot}

Calculate Fibrosis-4 (FIB-4) Index for Liver Fibrosis

Description

Calculate the extent of liver fibrosis/scarring in HCV/HBV patients without biopsy or ultrasound, as deduced by Sterling et al. 2006. Patient validation has not been included in patients <35 or above 65. As validated by Kim et al. 2010 and McPherson et al. 2017, a FIB-4 score of <1.45 is a fibrosis stage of 0-1, FIB-4 1.45-3.25 is a stage of 2-3, and FIB-4 of >3.25 is a tage of 4-6.

Usage

fib4(age, ast, alt, plt)

Arguments

age

Numeric value of age in years.

ast

Numeric value of aspartate aminotransferase in U/L.

alt

Numeric value of alanine aminotransferase in U/L.

plt

Numeric value of platelets in 10^3/uL or 10^9/L.

Value

A numeric value/vector with predicted level of FIB-4 index liver fibrosis.

References

Sterling, R.K., Lissen, E., Clumeck, N., Sola, R., Correa, M.C., Montaner, J., S. Sulkowski, M., Torriani, F.J., Dieterich, D.T., Thomas, D.L., Messinger, D. and Nelson, M. (2006), Development of a simple noninvasive index to predict significant fibrosis in patients with HIV/HCV coinfection. Hepatology, 43: 1317-1325. https://doi.org/10.1002/hep.21178 Kim BK, Kim DY, Park JY, et al. Validation of FIB-4 and comparison with other simple noninvasive indices for predicting liver fibrosis and cirrhosis in hepatitis B virus-infected patients. Liver Int. 2010;30(4):546-553. doi:10.1111/j.1478-3231.2009.02192.x Mcpherson S, Hardy T, Dufour JF, et al. Age as a Confounding Factor for the Accurate Non-Invasive Diagnosis of Advanced NAFLD Fibrosis. Am J Gastroenterol. 2017;112(5):740-751.

Examples

# The function is defined as
fib4(40,15,7,175)