CushieBlog

Introduction

Endogenous Cushing´s syndrome (CS) is a rare disorder with an incidence of 0.2–5.0 per million people per year (1, 2). The predominant subtype (accounting for about 80%) is adrenocorticotropic hormone (ACTH)-dependent CS. The vast majority of this subtype is due to an ACTH-secreting pituitary adenoma [so called Cushing´s disease (CD)], whereas ectopic ACTH-secretion (e.g. through pulmonary carcinoids) is much less common. In contrast, ACTH-independent CS can mainly be attributed to cortisol-producing adrenal adenomas. Adrenocortical carcinomas, uni-/bilateral adrenal hyperplasia, and primary pigmented nodular adrenocortical disease (PPNAD) may account for some of these cases as well (3, 4).

Coexistence of different subtypes of endogenous CS in single individuals is even rarer but has been described in few reports. These cases were usually observed in the context of prolonged ACTH stimulation on the adrenal glands, resulting in micronodular or macronodular hyperplasia (5–9). A sequence of CD and PPNAD was also described in presence of Carney complex, a genetic syndrome characterized by the loss of function of the gene encoding for the regulatory subunit type 1α of protein kinase A (PRKAR1A) (10). Moreover, another group reported the case of a patient with Cushing’s disease followed by ectopic Cushing’s syndrome more than 30 years later (8). To our knowledge, however, we here describe the first case report on a single patient with a cortisol-producing adrenocortical adenoma and subsequent CD.

Read the rest of the article at https://www.frontiersin.org/articles/10.3389/fendo.2021.731579/full