Endocrine Abstracts

Introduction: Pituitary adenomas are rare in infants and adolescents. Prolactinomas account for 50% of these pituitary adenomas. In adolescent girls, it is usually a microprolactinoma revealed by puberty delay or amenorrhea. We report a rare case of a macroprolactinoma in an adolescent girl revealed by visual impairment.

Case presentation: A 15-year-old adolescent girl presented with loss of vision over a long period of time. Magnetic resonance imaging revealed an expansive sellar and suprasellar mass measuring 48x47x37 mm consisting of cystic and solid components in favor of craniopharyngioma. Patient underwent transsphenoidal surgery for tumor resection. Post operative labroratory findings were in favor of a hyperprolactinemia with prolactine of 600 ng/ml and a thyrotrope deficiency. Histological assessment confirmed diagnosis of prolactinoma. Pituitary MRI control revealed a 20x9x17mm residual macroadenoma. Patient was started on cabergoline resulting in lowering prolactin levels and tumor shrinkage.

Discussion: Prolactinomas are rarely found in adolescents. Tumoral syndrome with visual impairment can be seen in large tumors in males. In girls, the most frequent presentation is a microprolactinoma revealed by amenorrhea. Less frequently, it can be revealed by pubertal delay or short stature. In our case, the patient presented with a macroprolactinoma revealed by visual impairment that was initially accounted for a craniopharyngioma. Medical treatment by dopamine agonists like in adults is the first line therapy as it’s effective in up to three quarters of cases.

Conclusion: Prolactin levels should be measured in every child or adolescent with visual impairment and a large suprasellar tumor to rule out a prolactinoma that can be successfully managed by medical therapy.