Overview
Contiguous ABCD1 DXS1357E deletion syndrome involves a genetic deletion on the Xp21 region, often encompassing genes responsible for glycerol kinase deficiency (GKD), Duchenne muscular dystrophy (DMD), and congenital adrenal hypoplasia (CAH). This syndrome presents with a constellation of symptoms including metabolic disturbances, muscular dystrophy features, and adrenal insufficiency 1.Diagnosis
Clinical Presentation: Pseudohypertriglyceridemia, hypoadrenalism (hyponatremia, hyperpotasemia, dehydration), elevated creatine phosphokinase levels, and hypotonia 1.
Laboratory Tests:
- Elevated blood triglyceride levels (e.g., >1244 mg/dL) 1.
- Hyponatremia (e.g., <124 mmol/L) and hyperpotasemia (e.g., >6.9 mg/dL) 1.
- High creatine phosphokinase levels (e.g., >7019 IU/L) 1.
- Elevated glycerol concentrations in blood and urine indicative of GKD 1.
Genetic Testing: Array comparative genomic hybridization (CGH) to identify deletions in Xp21 involving DMD, GKD, and DAX1/NROB1 genes 1.Management
Glycerol Kinase Deficiency: Dietary management to control triglyceride levels; specific dietary recommendations may include low-fat diet and close monitoring 1.
Congenital Adrenal Hypoplasia: Hormone replacement therapy, typically glucocorticoids and mineralocorticoids (e.g., hydrocortisone and fludrocortisone) to manage hypoadrenalism 1.
Muscular Dystrophy: Supportive care including physical therapy and monitoring for respiratory complications; specific DMD treatments like corticosteroids may be considered based on clinical progression 1.Special Populations
Pediatrics: Early diagnosis and multidisciplinary management are crucial for optimal outcomes, including nutritional support and regular monitoring of adrenal function and muscle health 1.Key Recommendations
Perform array CGH to confirm contiguous gene deletions in Xp21 involving DMD, GKD, and DAX1/NROB1 genes for accurate diagnosis (Evidence: Moderate) 1.
Initiate hormone replacement therapy with glucocorticoids and mineralocorticoids for managing hypoadrenalism in patients with confirmed CAH (Evidence: Moderate) 1.
Implement dietary management strategies to control hypertriglyceridemia associated with GKD, including low-fat diets and regular monitoring (Evidence: Weak) 1.References
1 Sevim U, Fatma D, Ihsan E, Gulay C, Nevin B. A neonate with contiguous deletion syndrome in XP21. Journal of pediatric endocrinology & metabolism : JPEM 2011. link