Background: Holoprosencephaly (HPE) is the most common developmental defect of the forebrain and mid-face in humans. It is a disorder of neural induction in which a genetic programming defect results in noncleavage of the forebrain in the sagittal plane and variable hypoplasia of paramedian structures. It occurs in 5-12/10,000 live births. Clinically, there is a nearly continuous spectrum of malformations consistent with HPE. Endocrinopathies, such as diabetes insipidus, hypothyroidism, hypocorticism, and growth hormone deficiency, are frequently associated with HPE. Seizures may occur.
Case report: We report a new case of semilobar-HPE complicated by neurogenic hypernatremia and no signs of dehydration in a child with microcephaly, spasticity, mental and psychomotor retardation, frontal bones hypoplasia, and mild facial dysmorphism.