Abstract
Background
Chromosome 18q duplications are associated with a range of phenotypes often similar
to complete trisomy 18, variably including poor growth, feeding difficulties, congenital
malformations and dysmorphic facial features. Although 18q duplication patients may
have seizures and developmental impairment, brain MRI typically shows only variable
degrees of cerebral atrophy.
Patient
We present a boy with a 52.2 Mb 18q duplication in whom brain MRI in the neonatal
period showed striking white matter abnormalities, most notable in the frontal lobes.
His clinical presentation was otherwise in keeping with trisomy 18, including characteristic
facial features, hypotonia, cardiac malformation, rocker bottom feet, pectus excavatum,
short and broad thumbs and halluces, and diabetes insipidus.
Conclusion
Since not previously reported in association with 18q duplication, the observation
of cerebral white matter anomalies is particularly interesting. This radiologic pattern
is a well-recognized feature of 18q deletion syndrome, hypothesized by many to occur
due to haploinsufficiency of MBP, the gene encoding myelin basic protein. The mechanisms leading to the white matter
anomalies in this patient remain unexplained.
Keywords
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Article Info
Publication History
Published online: April 22, 2022
Accepted:
April 10,
2022
Received in revised form:
March 18,
2022
Received:
January 18,
2022
Identification
Copyright
© 2022 The Japanese Society of Child Neurology Published by Elsevier B.V. All rights reserved.
