Short stature in a patient with familial glucocorticoid deficiency

A 10.5-year-old Caucasian girl with familial glucocorticoid deficiency (FGD) is presented. She had a homozygous S74I mutation of the ACTH receptor and her parents were heterozygous for the same mutation. Around 4 years prior to the diagnosis of FGD, she was diagnosed with antibody positive primary hypothyroidism and was on thyroxin supplementation. FGD patients are considered to be tall. Our patient was only 146.5 cm (4' 9.25") tall at age 17 years (-2.21 standard deviations below the mean for her age). The possible mechanism for short stature in FGD is speculated.