Correlation between FIB- 4 Score and Liver Biopsy in Lean Egyptian Patients with Non-Alcoholic Fatty Liver Disease
Authors: Ali-Eldin Zainab Ahmed , Ali Hany , Raafat Khaled , Eldamhogy Yomna Nader Mohamed 
Published: August 2023

Background
Nonalcoholic fatty liver disease (NAFLD) is a worldwide epidemic with global prevalence estimated at 25%. Although NAFLD is usually associated with obesity, patients who are not obese can also present with NAFLD; this is known as “lean NAFLD.” Lean NAFLD is defined as NAFLD that develops in patients with a body mass index (BMI) &lt;25 kg/m2. The prevalence of lean NAFLD varies from 7% in the United States to as high as 19% in Asia. Unfortunately, being lean (not overweight) does not necessarily lead to better health. A recent large meta analysis by Sookoian and Pirola of almost 2,000 patients with NAFLD who were lean demonstrated that patients with NAFLD who are lean or obese share a common altered metabolic and cardiovascular profile, which in turn may lead to collective risk for adverse cardiometabolic outcomes, including diabetes and ischemic heart disease. Indeed, atherosclerotic cardiovascular disease remains the most common cause of death in all weight categories.
NAFLD comprises a wide pathological spectrum ranging from simple steatosis to steatohepatitis (NASH) with variable degrees of fibrosis and cirrhosis. The strongest predictor of fibrosis progression in NAFLD is the presence of steatohepatitis (Trenell et al., 2017).
The diagnosis of NASH mandates a liver biopsy, yet the risks and costs associated with a liver biopsy preclude its widespread use. Pain is almost universal, and there is bleeding in approximately 1 in 500 liver biopsies and death in 1 in 10,000, dissuading patients from undergoing the procedure. Moreover, the disproportionately increasing incidence of NAFLD calls for practical and costeffective care and monitoring (Estes et al.,2018). Methods for non-invasive assessment of fatty liver disease and studies in the field have exponentially appeared over the last three decades, offering a safe and more non-invasive practical approach to hepatic fibrosis and steatosis quantification (Castera et al.,2019).

Aim of the study
Determining the correlation of Fib-4 score and NAFL diagnosed by liver biopsy in lean Egyptian patients

Patients and Methods
This study had been carried out on 30 subjects, age range above 18 years old, with BMI (18.5-24.9) selected from transplantation donor outpatient clinic at Ain shams university specialized hospital in Cairo after informed consent were taken from the patients Subjects were divided as follow:
•Group I: 15 adult patients with NAFLD.
•Group II: 15 adult patient with normal liver biopsy who will be educated about lean NAFLD and how to prevent it.

Results
In the current study we concluded that FIB-4 score is not significant with degree of fibrosis while it has a negative correlation with steatosis assessed by biopsy. FIB-4 failed to discriminate advanced fibrosis. Conversely, it showed acceptable diagnostic performances in exclusion of advanced fibrosis in overweight, obese, and severely obese patients in other studies. (FATIH et al., 2020)

Conclusion
FIB-4 failed to discriminate advanced fibrosis. Conversely, it showed acceptable diagnostic performances in exclusion of advanced fibrosis in overweight, obese, and severely obese patients. FIB-4 was able to exclude advanced fibrosis with the highest diagnostic accuracy in the subgroup of overweight patients. so fib 4 score can’t be used as a marker of fibrosis nor steatosis in lean NAFLD patients but more like a prognostic value.