Neonatal presentation of familial glucocorticoid deficiency with a MRAP mutation: A case report

Familial glucocorticoid deficiency (FGD) is a rare autosomal recessive disorder in which the adrenal cortex fails to respond appropriately to stimulation by adrenocorticotropic hormone (ACTH) to produce cortisol. The disease is characterized in laboratory testing by glucocorticoid deficiency and markedly elevated ACTH levels. FGD may present in infancy or early childhood with symptoms related to low cortisol and high ACTH, such as hyperpigmentation, severe hypoglycemia, failure to thrive and recurrent infections. Mutations in the MC2R accessory protein (MRAP) cause FGD types 2, which accounts for approximately 15–20% of FGD cases. Here, we report a female neonate of Chinese Han origin, who presented with noted hyperpigmentation at birth. Laboratory investigations revealed hypocortisolaemia (cortisol