Familial glucocorticoid deficiency type 2 (FGD2) is a rare autosomal disorder caused by an melanocortin 2 receptor accessory protein ( MRAP ) mutation, typically presenting with hyperpigmentation, recurrent hypoglycemia, and preserved mineralocorticoid function. We describe a 2-year-old male child with tall stature, diffuse hyperpigmentation, recurrent infections, and hypoglycemic seizures. Endocrine evaluation confirmed isolated cortisol deficiency with markedly elevated adrenocorticotropic hormone, and genetic testing identified a pathogenic MRAP variant. Hydrocortisone replacement led to improved pigmentation and stabilization of glucose. This case highlights the importance of considering FGD2 in atypical presentation of primary adrenal insufficiency and emphasizes that early genetic confirmation and timely steroid therapy improve outcomes.
Arora et al. (Mon,) studied this question.