Middle interhemispheric variant of holoprosencephaly associated with diffuse polymicrogyria
Jun-Ichi Takanashi1, A James Barkovich, Nancy J Clegg
1Neuroradiology Section, Department of Radiology, University of California San Francisco, USA.
Insights
A rare genetic factor may cause multiple birth defects, including holoprosencephaly, polymicrogyria, and developmental issues in an infant. This case highlights unusual brain abnormalities and associated congenital anomalies.
Area of Science:
- Neuroscience
- Developmental Biology
- Medical Genetics
Background:
- Congenital anomalies present complex diagnostic challenges.
- Holoprosencephaly (HPE) is a spectrum of brain malformations.
- Neuronal migration disorders contribute to neurological deficits.
Observation:
- An 11-month-old boy presented with cleft palate, club foot, hypospadias, and myoclonic seizures.
- No teratogenic exposures were identified during pregnancy.
- Brain MRI revealed a middle interhemispheric fusion variant of holoprosencephaly, diffuse polymicrogyria, and a hypoplastic brainstem.
Findings:
- The patient exhibited an unusual combination of craniofacial, genitourinary, and neurological abnormalities.
- Brain imaging demonstrated significant structural brain malformations, including HPE variant and polymicrogyria.
- The constellation of findings suggests a potential underlying genetic etiology impacting early brain development.
Implications:
- This case underscores the importance of comprehensive evaluation for syndromic presentations of congenital anomalies.
- Identifying the genetic factor could improve understanding of prosencephalon cleavage, neuronal migration, and organization.
- Further research into rare genetic disorders is crucial for advancing diagnostics and potential interventions.
Abstract:
An 11-month-old boy was discovered to have a cleft palate, club foot, hypospadias, and myoclonic seizures. No in utero exposure to teratogens was identified. Brain MR imaging revealed a middle interhemispheric fusion variant of holoprosencephaly, diffuse polymicrogyria, and a hypoplastic brain stem; this was a distinctly unusual association of findings. We hypothesize that an unknown genetic factor causes disturbances of cleavage of the prosencephalon as well as neuronal migration and organization.
