A rare genetic disorder causing persistent severe neonatal hypoglycaemia the diagnostic workup
Gaia Francescato1, Alessandro Salvatoni, Luca Persani
1Department of Neonatology and NICU, Ospedale Filippo Del Ponte, Varese, Italy. gaia.francescato@yahoo.it
BMJ Case Reports
|July 21, 2012
Summary
Familial glucocorticoid deficiency (FGD) is a rare genetic disorder. Early blood sample collection during hypoglycemia is crucial for diagnosing FGD, especially in newborns presenting with seizures and respiratory issues.
Area of Science:
- Genetics
- Endocrinology
- Pediatrics
Background:
- Familial glucocorticoid deficiency (FGD) is a rare autosomal-recessive disorder.
- Key features include skin hyperpigmentation, severe hypoglycemia, seizures, feeding difficulties, and infections.
- A newborn presented with seizures and respiratory insufficiency, complicating initial diagnosis.
Observation:
- A newborn presented with seizures and respiratory insufficiency.
- Hyperpigmentation was not apparent due to ethnic background.
- Initial presentation suggested a broad differential diagnosis.
Findings:
- Laboratory results and molecular analysis confirmed FGD.
- A known MC2R:p.Y254C mutation associated with type 1 FGD was identified.
- Two novel heterozygous polymorphisms in the melanocortin 2 receptor accessory protein-α gene were discovered, with an unknown role in FGD.
Implications:
- This case highlights the diagnostic challenges of FGD, particularly when typical signs like hyperpigmentation are absent.
- Early identification and management of hypoglycemia are critical in affected newborns.
- The discovery of novel polymorphisms warrants further investigation into their potential contribution to FGD pathogenesis.
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