The longest reported survival of a child with McCune–Albright syndrome and a severe early presenting phenotype consisting of neonatal cushing syndrome, cardiac and liver diseases

Neonatal cushing syndrome (NCS) is a rare disease that results from prolonged exposure to high cortisol levels. McCune–Albright syndrome (MAS) is an exceedingly rare genetic disorder characterized by cafe-au-lait skin spots, bone fibrous dysplasia and multiple endocrinopathies. We describe a case of a premature neonate with Intrauterine Growth Retardation who presented with hypercortisolemia, neonatal transaminitis and cardiac dysfunction. Further evaluation revealed significant bilateral adrenal hyperplasia leading to the diagnosis of NCS as part of MAS. Despite maximum medical therapy, including metyrapone, the baby’s refractory hypertension, hyperglycemia and persistent failure to thrive (weight of 1.4 kg at corrected age 38 weeks) necessitated bilateral adrenalectomy. This case did not initially demonstrate the classic MAS triad, notably, the absence of skeletal manifestations. There has been no previous description of a baby who has had all the early life-threatening features present and survived beyond 18 months. This case highlights the severity of the phenotype and the challenges involved in diagnosing and treating NCS and MAS in neonates.