Hereditary hepatic fibrinogen storage disease with a novel fibrinogen variant FGG c.1113T>A (fibrinogen Seoul III)

Hereditary hepatic fibrinogen storage disease (HHFS) is an extremely rare genetic disorder caused by mutations in the fibrinogen gamma (FGG) gene. Clinical presentations range from asymptomatic cases to severe symptoms. We present the case of a 9-year-old boy with persistently elevated liver enzymes who exhibited no clinical symptoms. A liver biopsy revealed hepatic fibrinogen storage disease, and genetic testing identified a heterozygous mutation, c.1113T>A, p.(Asn371Lys) in FGG. This is the first reported case of HHFS in Korea, as well as the first report of this novel mutation. Multigene panel testing played a crucial role in diagnosing this rare condition. Following three months of ursodeoxycholic acid medication, liver enzyme levels normalized, and the patient is currently under follow-up.