A previously healthy 6 week old female infant is found unresponsive in her crib. In the emergency depament, she is noted to be well developed and well nourished with normal blood pressure and appearance of the genitalia but with increased pigmentation of her skin. Blood glucose level is 30 mg/dL. The most likely diagnosis is aEUR'

Familial glucocoicoid deficiency Familial glucocoicoid deficiency is a rare autosomal recessive condition. It is characterized by adrenal insufficiency. The pathological examination of the adrenal gland reveals that:- This causes low coisol concentration because the zona fasciculata is primarily responsible for glucocoicoid production. Because the zona glomerulosa is well preserved mineralocoicoid action is usually unaffected. Low circulating serum coisol results in lack of feedback inhibition to the hypothalamus which results in increased ACTH secretion from pituitary. Clinical features Zona glomerulosa --> well preserved Zona fasciculata atrophied Zona reticularis --> atrophied Patients with familial glucocoicoid deficiency generally presents with signs and symptoms of "adrenal insufficiency" with the impoant distinction that mineralocoicoid production is always normal. The most common initial presenting sign is "deep hyperpigmentation" of the skin, mucous membrane or both as a result of the action of adrenocoicotrophic hormone (ACTH) on cutaneous melanocyte stimulating hormone (MSH) receptors. The symptoms are compatible with glucocoicoid deficiency. Many patients presents with recurrent hypoglycemia or severe infections. - In the neonatal period, frequent presenting signs include - feeding problems, failure to thrive, regurgitation and hypoglycemia manifesting as seizures