[Cushing's syndrome: special issues].

The present article reviews: Corticotrophin (ACTH) independent bilateral macronodular adrenal hyperplasia, which is characterized by aberrant adrenal receptors due to either ectopic expression or to overexpression (eutopic expression). Micronodular adrenal hyperplasia, which provokes small pigmented nodules in the adrenal gland with atrophy of the internodal tissue. These nodules may not be visible on imaging tests. The term subclinical Cushing's syndrome, coined in 1981, should be used in patients with clinically non-functioning adrenal adenomas but who show autonomous cortisol production that is insufficient to generate overt Cushing's syndrome. This entity must be distinguished from preclinical Cushing's syndrome, given that the subclinical form does not necessarily herald the development of symptoms of hypercortisolism. Cushing's syndrome is uncommon in children and adolescents. Regarding the general incidence of the disease, only 10% of cases are diagnosed in this age group. The most common cause of endogenous Cushing's disease in children older than 7 years is ACTH-dependent Cushing's disease (85%). The association of Cushing's syndrome and pregnancy is highly uncommon, since hypercortisolism usually causes amenorrhea, oligomenorrhea and infertility due to inhibition of gonadotropin secretion. One hundred thirty-six pregnancies have been described in 122 women, with a gestational age at diagnosis of 18.4+/-1 weeks.