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Hydrocephalus in an infant with trisomy 22
F Fahmi1, S Schmerler, R G Hutcheon
1Department of Pediatrics, St Joseph's Hospital and Medical Center, Paterson, New Jersey 07503.
Journal of Medical Genetics
|February 1, 1994
Summary
This study details a rare case of true trisomy 22 in an infant, confirmed by karyotype analysis. The patient exhibits known features of this condition, plus novel findings like macrocephaly and hydrocephalus.
Area of Science:
- Genetics
- Developmental Biology
- Pediatrics
Background:
- Trisomy 22 is a rare chromosomal abnormality.
- Accurate diagnosis requires karyotype analysis to rule out mosaicism.
Observation:
- A neonate presented with features consistent with trisomy 22.
- Karyotype analysis confirmed a 47,XX,+22 karyotype from multiple germ layers, excluding mosaicism.
Findings:
- The infant displayed developmental delay, ear abnormalities, micrognathia, clefting, and congenital heart disease.
- New observations include macrocephaly and hydrocephalus, previously unreported in true trisomy 22.
- The patient also presented with holoprosencephaly, a rare occurrence in this condition.
Implications:
- This case expands the phenotypic spectrum of true trisomy 22.
- Highlights the importance of comprehensive genetic and physical evaluations in infants with suspected chromosomal abnormalities.
- Further research is needed to understand the genotype-phenotype correlations in trisomy 22.
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