Clinical features and outcomes of holoprosencephaly in Korea.

The clinical spectrum of holoprosencephaly is broad, and its etiology is heterogeneous. To investigate the clinical spectrum of holoprosencephaly in Korea, we performed a database analysis of 55 cases of holoprosencephaly, including 12 diagnosed postnatally, all from a single institution. The 55 patients were categorized into several types: 37 alobar, eight semilobar, eight lobar, and two middle interhemispheric variant. Associated brain (41.8%) and craniofacial (74.5%) features varied substantially. Of 40 patients studied according to karyotype, chromosomal aberrations were detected in 18 (45.0%). Twenty-seven (49.1%) patients, diagnosed postnatally, exhibited milder types of holoprosencephaly and less profound craniofacial malformations than in prenatal diagnoses. Moreover, in postnatally diagnosed patients, the subgroup surviving longer than 1 month also exhibited a milder holoprosencephaly type and lower incidence of associated craniofacial malformations. The most frequent clinical signs in living children with holoprosencephaly included microcephaly, global developmental delay, and seizures. Holoprosencephaly represents a heterogeneous entity with different clinical manifestations and etiologies. A high index of suspicion, coupled with appropriate imaging studies, can enable accurate diagnoses and prognoses of holoprosencephaly.