MASLD-F Algorithm to the Rescue: Improving Noninvasive Diagnosis of Hepatic Fibrosis in Patients With Severe Obesity

The gold standard to stage hepatic fibrosis is with a liver biopsy. It is not without its drawbacks and is more challenging for patients with severe obesity. Noninvasive testing, including the fibrosis-4 (FIB-4) score and vibration-controlled transient elastography (VCTE), have begun to be increasingly used as initial screening methods.The applicability and accuracy of these noninvasive methods remain uncertain in patients with severe obesity and metabolic dysfunction-associated steatotic liver disease. Our study explored combining VCTE with lower FIB-4 cutoffs to improve concordance with biopsy in staging hepatic fibrosis in patients with metabolic dysfunction-associated steatotic liver disease and severe obesity undergoing bariatric surgery.

A total of 632 patients with severe obesity underwent preoperative VCTE and intraoperative liver biopsy during bariatric surgery from January 2020 to August 2021. Variables collected included patient demographics, laboratory values, abdominal ultrasound, VCTE, and liver biopsy results. Analysis of variance 1-way test, χ 2 tests, and Fisher exact tests were used for quantitative and qualitative variables, respectively. The 95% CIs for the mean FIB-4 scores were used to generate surrogate cutoff values. The VCTE and FIB-4 scores were integrated using an algorithm that utilized a dynamic decision-making process at each stage to find the values that would yield the highest concordance with liver biopsy.

VCTE alone was in concordance with liver biopsy results in 59.7% of cases. Combining the proposed FIB-4 cutoff scores with VCTE led to an improved concordance with a liver biopsy of 88%.

Our study demonstrated that accessible noninvasive testing has limitations alone but when combined, can improve staging of hepatic fibrosis.