West syndrome associated with mosaic Down syndrome
Madoka Kajimoto1, Takashi Ichiyama, Akiko Akashi
1Department of Pediatrics, Yamaguchi University Graduate School of Medicine, 1-1-1 Minamikogushi, Ube, Yamaguchi 755-8505, Japan. h003uc@yamaguchi-u.ac.jp
Brain & Development
|February 20, 2007
Summary
West syndrome, a severe epilepsy, can occur with mosaic Down syndrome. Chromosomal analysis is vital for diagnosing unexplained infantile epilepsy, as seen in this case where ACTH therapy proved effective.
Area of Science:
- Pediatric Neurology
- Clinical Genetics
- Epileptology
Background:
- West syndrome is an epilepsy syndrome characterized by infantile spasms, hypsarrhythmia on EEG, and developmental delay.
- Down syndrome is a genetic disorder caused by trisomy 21, typically associated with characteristic facial features and intellectual disability.
- Mosaic Down syndrome involves a mix of cells, some with trisomy 21 and some with a normal chromosome count.
Observation:
- A 6-month-old girl presented with West syndrome, including repetitive tonic spasms and hypsarrhythmia on electroencephalography (EEG).
- The patient exhibited a normal facial appearance and no minor anomalies, which are often associated with Down syndrome.
- Karyotype analysis revealed mosaic Down syndrome (46,XX/47,XX,+21).
Findings:
- Adrenocorticotropin (ACTH) therapy was administered and found to be effective in managing the infantile spasms.
- The patient achieved a developmental quotient of 76 at 17 months of age.
- This case highlights a rare presentation of West syndrome co-occurring with mosaic Down syndrome.
Implications:
- The findings underscore the importance of chromosomal analysis in infants presenting with unexplained epilepsy, even in the absence of typical Down syndrome features.
- Early diagnosis and appropriate treatment, such as ACTH therapy, can lead to improved developmental outcomes in children with complex genetic and neurological conditions.
- This case contributes to the understanding of the phenotypic variability in mosaic Down syndrome and its association with early-onset epileptic encephalopathies.
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