Endocrine Abstracts

JOINT585

Introduction: Prolonged corticosteroid therapy exerts a negative feedback control on the hypothalamic-pituitary axis, resulting secondary adrenal insufficiency. Recovery of normal adrenocortical axis function is most often spontaneous. We report here a case of non-secreting pituitary adenoma revealed by corticosteroid therapy.

Observation: A 20-year-old woman was referred to us for the management of a pituitary microadenoma evolving in the context of Cushing’s syndrome. During questioning, a skin allergy is reported for which long-term corticosteroid therapy had been prescribed. Not having been properly informed, the patient abruptly interrupted her treatment and consulted her doctor because of the sudden onset of asthenia and arterial hypotension, in which case a requested hormonal assessment revealed a low cortisol level at 40.19 nmol/lwith non-increasing ACTH level at 9.67 pg/ml. Having been convinced of the central origin of the adrenal insufficiency, and disregarding corticosteroid intake notion, magnetic resonance imaging was requested, revealed a 4 mm pituitary microadenoma left side. It should be noted that the rest of pituitary assessment did not objectify any hypo or hypersecretion of the other axes. After a withdrawal protocol, cortisol levels at 3 months had returned to 339.50 nmol/l, and the patient was still being followed-up.

Discussion: Pituitary adenomas of any type are rare. intrasellar lesions prevalence in the general population is 6-10%, mainly microadenomas. Non-functional pituitary adenomas are pituitary tumours that do not secrete any hormone. Since 1948, synthetic corticosteroids are widely used in medical practice due to their anti-inflammatory, anti-allergic and immunosuppressive properties. Addition to their therapeutic effects, corticosteroids exert a negative feedback effect on the corticotropic axis, inhibiting the secretion of ACTH and cortisol. This phenomenon is also called iatrogenic or exogenous Cushing’s syndrome.

Conclusion: Better management of prolonged corticosteroid therapy will help us to assess the real adrenal insufficiency incidence, and to propose adequate prevention of this side effect.