A high FIB-4 score may be an early sign of severe liver involvement in patients with primary antibody deficiencies.

Background/aim: Liver damage is a significant complication that increases mortality and morbidity in primary immunodeficiencies (PIDs). Although biopsy is the gold standard, the fibrosis-4 (FIB-4) scoring system is a noninvasive method for diagnosing liver fibrosis. In this study, we investigated the value of the FIB-4 score as an early indicator of liver damage in patients with primary antibody deficiencies (PADs). Materials and methods: Of 52 patients, 40 had common variable immunodeficiency (CVID), 12 had immunoglobulin G subclass deficiency (IgG-SGD), and they were enrolled in the study. Patients were divided into hematology, rheumatology + dermatology, gastroenterology/hepatology, and respiratory diseases groups based on their clinical phenotypes. FIB-4 score calculation and transient elastography were used to detect liver complications. Results: FIB-4 scores were significantly higher in CVID patients than in those with SGD (p = 0.003), and were also elevated in PAD patients with hematology and gastroenterology/hepatology phenotypes compared with rheumatology + dermatology and respiratory phenotypes (p < 0.001). In the gastroenterology/hepatology group patients, FIB-4 scores showed a strong positive correlation with elastography values ( Conclusions: This study is the first to show that FIB-4 may serve as a practical and noninvasive indicator of liver damage in PADs.