Cushing's syndrome due to Carney complex in two siblings

Carney complex (CNC), an inherited disorder, is rarely diagnosed in children. We present two siblings diagnosed with CNC. The younger sister presented with primary amenorrhoea, while the brother sought evaluation for weight gain. Both siblings were cushingoid. The sister displayed characteristic features of CNC, including facial lentigines, adrenocorticotropic hormone (ACTH)-independent Cushing's syndrome (CS), a paradoxical cortisol rise in response to dexamethasone and primary pigmented nodular adrenocortical disease (PPNAD). The second case was more challenging as he had CS but normal ACTH. Imaging was unremarkable, showing normal pituitary and adrenal glands. A previously unknown variant of the PRKAR1A gene mutation was found in both siblings. Given the sibling's history and genetic findings, bilateral adrenalectomy was performed, confirming PPNAD. The past 5 years of follow-up have been unremarkable. Although CNC often presents as CS, evaluating beyond is crucial, as CNC includes endocrine and non-endocrine tumours. Diagnosis is challenging, necessitating a thorough family history, examination and genetic testing.