Endocrine Abstracts

Introduction: Pituitary adenomas represent 10 to 20% of intracranial tumors. In children, craniopharyngioma are the most common tumor of the sellar region. The symptoms can include headache, vomiting, pituitary deficiency and in pituitary adenomas, hormonal excess. The visual examination can find a visual field defect such as a bitemporal hemianopsia. We present a rare case of a pituitary adenoma in a 15-year-old girl with binasal hemianopsia.

Observation: A 15-year-old girl presented frontal headaches and vomiting occurring for a year before her referral to our department. At physical examination, she had a normal blood pressure, and clinical visual field assessment suggested an inferior and right nasal quadrianopsia. Firstline imaging investigations with cerebral tomography discovered a pituitary adenoma. A biopsy with immunohistochemistry was performed confirming the diagnosis of a plurihormonal LH and prolactin sparsely granulated pituitary adenoma. The magnetic resonance imaging confirmed intra and suprasellar adenoma measuring 26.4*20*21mm abutting optic chiasma and the third ventricule. On hormonal investigations, she had a corticotropin deficiency with a peak cortisol after insulin tolerance test at 300 nmol/l and ACTH levels at 26 pg/ml. She didn’t have thyrotropin deficiency nor diabetes insipidus. Her menses were irregular, with a secondary amenorrhea of one year at three years after menarche. There wasn’t any sign of hormonal excess, the prolactin levels were at 33µg/l, probably secondary to the pituitary stalk compression. A type 1 multiple endocrine neoplasia was excluded as there were no family history of endocrine disease and parathormone levels were normal. The visual field assessment concluded to bilateral defects with a pattern of an incomplete binasal hemianopsia. She was put on 15 mg of hydrocortisone and was referred to surgery.

Conclusion: The suprasellar extension of pituitary adenoma abutting the optic chiasma is responsible of a bitemporal hemianopsia as the optic nerves in the chiasma are responsible for the vision in those fields. A binasal defect can be seen in ophthalmologic pathology, but is extremely rare in pituitary adenoma. Pituitary adenoma prevalence in children and adolescents is less than 5%. This case represents an unusual clinical presentation of a pituitary tumor confirmed to be a pituitary adenoma in a 15-year-old girl with an exceptional optic defect.