Fetal hydantoin syndrome
Causes and risk factors
It occurs in babies whose mothers have taken phenytoin (diphenylhydantoin) during pregnancy as an anticonvulsant. There are no precise data on the incidence and prevalence of this syndrome; however, it is believed that fetal hydantoin syndrome in various clinical manifestations affects approximately 4-7% of newborns exposed to the drug in the womb.
Which are the symptoms?
Intrauterine exposure to this drug can cause: - the presence of certain dimorphisms at birth (low-set hairline, short neck with pterygia, ugly ears, small nose, sunken bridge of the nose, epicanthus, hypertelorism, macrosomia, distal phalanges of hypoplastic hands and feet and a digitized thumb);- possible growth retardation; - possible delay in psychomotor development with neurological deficit (about 1-11% of cases); - the risk of cleft mouth and heart defects; - an increased risk of developing benign or malignant tumors, such as neuroblastoma or other types of cancer in children (ependymoma, ectodermal tumors, Wilms tumor).
How is it diagnosed?
How is it treated?
As a preventive measure against malformations, women who are taking phenytoin and planning to become pregnant should be given a folic acid supplement and started taking the vitamin before conception. Unfortunately, the damage done by phenytoin during pregnancy is irreversible; that's why prevention is important. After the identification of children with fetal hydantoin syndrome, supportive therapy is carried out to minimize the manifested somatic or intellectual impairments.