A neonate with contiguous deletion syndrome in XP21
Unal Sevim1, Demirel Fatma, Esen Ihsan
1Ankara Child Disease, Hematology and Oncology Training Hospital - Neonatalogy, Ankara, Turkey. sevimunal@yahoo.com
Journal of Pediatric Endocrinology & Metabolism : JPEM
|February 8, 2012
Summary
This case highlights contiguous gene deletion syndrome in Xp21, presenting with pseudohypertriglyceridemia and hypoadrenalism in an infant. Early diagnosis and treatment of metabolic complications are crucial for affected infants.
Area of Science:
- Genetics
- Pediatrics
- Endocrinology
Background:
- Contiguous gene deletion syndrome in Xp21 is a rare genetic disorder.
- It can present with a constellation of symptoms including muscular dystrophy, glycerol kinase deficiency, and hypoadrenalism.
Observation:
- A male infant presented with failure to gain weight, dehydration, hypotonia, and scrotal hyperpigmentation.
- Laboratory findings revealed hyponatremia, hyperkalemia, elevated creatine phosphokinase, and pseudohypertriglyceridemia.
Findings:
- Muscle biopsy showed nonspecific atrophic findings, and dystrophin gene analysis was negative.
- Further tests indicated glycerol kinase deficiency (GKD).
- Array comparative genomic hybridization (CGH) confirmed a deletion in Xp21 encompassing genes for Duchenne muscular dystrophy (DMD), GKD, and congenital adrenal hypoplasia (DAX1/NROB1).
Implications:
- Early recognition of Xp21 contiguous gene deletion syndrome is vital for infants with myopathic symptoms and metabolic derangements.
- Prompt diagnosis and management, including mineralocorticoid therapy, can prevent severe metabolic complications and improve outcomes.
- Geneticists should consider comprehensive deletion studies for this syndrome.
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