Adrenal myelolipoma(s) as presenting manifestation of subclinical Cushing’s disease (eutopic ACTH-dependent Cushing’s syndrome)

Abstract

Primary adrenal myelolipomas, relatively rare benign tumours of the adrenal cortex are typically unilateral, hormonally inactive and asymptomatic, hence often diagnosed as 'adrenal incidentaloma'. Bilateral adrenal myelolipomas, in particular, may be associated with underlying endocrinopathies associated with elevated circulating adrenocorticotropic hormone (ACTH) concentration. Subclinical cortisol hypersecretion, irrespective of its ACTH dependency, does not manifest typical clinical phenotype of hypercortisolemia, and thus termed subclinical Cushing's syndrome. In this article, hormonal evaluation in a middle-aged woman with diabetes, hypertension and incidentally discovered unilateral adrenal myelolipoma revealed underlying subclinical Cushing's disease. Abdominal CT revealed another tiny focus in the contralateral adrenal gland, probably representing incipient myelolipoma.

Bilateral adrenal myelolipomas presenting as acute adrenal insufficiency in an adult with congenital adrenal hyperplasia

“…It is hypothesised that AMs result from altered haematopoietic cell functioning and hormonal stimuli 1. Conditions with high circulating ACTH, such as is the case of untreated CAH, have been associated with AI, and AM specifically 2 3. Chronic stimulation of the adrenal tissue leads to adrenal cortex hyperplasia and subsequently the formation of adrenal tumours.…”

Bilateral Adrenal Myelolipomas Presenting as Acute Adrenal Insufficiency in an Adult With Congenital Adrenal Hyperplasia

“…The mature adipocytes then stimulate the adjacent adrenal cortex tissue to release granulocyte-colony stimulating factor to recruit circulating hematopoietic cells from blood stream to settle and form a myelolipoma. Conditions in which circulating ACTH is high, have been associated with AM, likely due to chronic stimulation of the adrenal tissue 3,4 . Bilateral AMs are frequently found in untreated patients with CAH who have high ACTH levels, supporting the role of hormonal stimulation on the development of these lesions.…”