Endocrine Abstracts

Cushing’s disease (CD) is the most common cause of endogenous Cushing’s syndrome in children and adolescents and represents a rare cause of short stature. A 14-year-old boy came to our attention for progressive weight gain and short stature. Birth length and weight were normal; clinical history was negative for use of glucocorticoids. At examination, height was 140 cm (3th centile), weight was 37.7 kg (10th centile). Tanner stage was: G2, PH 3, testis 3 ml. Hypothyroidism and growth hormone deficiency were excluded. A marked increase of urinary free cortisol, a nonsuppressible serum cortisol after Liddle 1 test and an elevated ACTH value confirmed the diagnosis of ACTH dependent Cushing’s syndrome. Pituitary MRI showed a left microadenoma and an other right focal area of lesser enhancement. Therefore, bilateral inferior petrosal sinus sampling (BIPSS) with CRH stimulation was performed to obtain an accurate preoperative localization of the adenoma: the interpetrosal sinus ACTH gradient indicated lateralization of ACTH secretion to the left side. The patient underwent transsphenoidal surgery with selective microadenomectomy, with an immediate ACTH decline in the postoperative phase. Histology confirmed the diagnosis of corticotrophic pituitary adenoma. Glucocorticoid replacement therapy was instituted. Clinical examination demonstrated a rapid catch-up growth (10th centile), with a normalization of body mass index and an adequate pubertal development.

This is a rare case of pediatric Cushing disease: one of the most reliable indicators of hypercortisolism in these patients is growth failure associated with weight gain while laboratory data and pituitary MRI are very important tools to confirm the clinical suspicion. In our case, BIPSS was necessary to lateralise the site of ACTH production, because of the co-existence of an ACTH secreting microadenoma and a pituitary ‘incidentaloma’. Transsphenoidal surgery allowed a successful remission of hypercortisolism, with a dramatic improvement of auxological parameters.