Disease that is characterized clinically by neonatal hyperpigmentation, hypoglycemia, failure to thrive, and recurrent infections and biochemically by glucocorticoid deficiency without mineralocorticoid deficiency. The disease usually presents in infancy or early childhood. Hypoglycemic crises resulting in convulsions can lead to coma or death if untreated and recurrent hypoglycemia may lead to neurological sequelae. Most cases are caused by defects in the adrenocorticotropin receptor, or its signaling pathway resulting in a failure of the cells of zona fasciculata in the adrenal cortex to respond appropriately to adrenocorticotrophic hormone, leading to a glucocorticoid deficiency. These defects are most commonly caused by mutations in MC2R (18p11.2) and MRAP (21q22.1). Other mutations reported include MCM4 (8q12-q13), NNT (5p12) and TXNRD2 (22q11.21). Inherited in an autosomal recessive manner.