Genetic, Clinical, and Biochemical Characterization of a Large Cohort of Palestinian Patients With Fanconi-Bickel Syndrome

This study aims to investigate the clinical, biochemical, and genetic characteristics of Fanconi-Bickel syndrome (FBS) in a cohort of 20 individuals from Palestine and to identify novel pathogenic variants. A retrospective analysis was conducted on medical records from Al-Makassed Hospital's pediatric department spanning 2015 to 2023. Individuals diagnosed with FBS via molecular genetic testing were included in the study. Among the 20 genetically confirmed FBS patients, hepatomegaly was prevalent in 95%, whereas 70% exhibited both developmental delay and hypophosphatemic rickets, and 68.4% experienced growth retardation. Hypertriglyceridemia (HTG) was universal. Elevated liver enzymes and alkaline phosphatase were common, along with hypophosphatemia (95%) and urinary abnormalities. Genetic analysis revealed five distinct SLC2A2 pathogenic variants, including three previously unreported variants: p.Gln23Arg (c.68A > G), p.Thr353Arg (c.1058_1059delinsGG), and an exon 7 deletion. This study presents the largest single-center cohort of FBS patients, expanding our understanding of the disorder's phenotypic and genotypic spectrum. Despite FBS generally carrying a favorable prognosis, timely diagnosis remains crucial to prevent severe complications.