Endocrine Abstracts

Introduction: Neurofibromatosis type 1 (NF1) is the most common type of NF, and accounts for about 90% of all cases. Primary empty sella syndrome (ESS) results from herniation of arachnoid mater into the pituitary fossa. Since it has been demonstrated that the small anterior pituitary size reflects loss of neurofibromin expression in the hypothalamus, leading to reduced GHRH, pituitary GH and IGF1 production, we agree that IGF1 and GH increased in our patient can be challenging.

Case report: We report the case of a 33-year-old woman, diagnosed in childhood with NF1, with a single spontaneous menstrual cycle at 14 years, secondary amenorrhea and oestroprogestative substitution treatment ever since, diagnosed with primary ESS, hydrocephaly and central ventricular system malformation at 18 years. Physical examination revealed six café au lait macules on the trunk and neck, multiple cervical, supraclavicular and upper thorax plexiform neurofibromas. Blood pressure was 115/100 mm/Hg, without orthostatic hypotension. The fluid intake was normal. She had no hystory of head trauma, pregnancy or childbirth. Lab tests:IGF1=413 ng/ml (115–307 ng/ml) ACTH=12.6 pg/ml, TSH=0.893 μIU/ml, FT4=0.851 ng/dl, TPOAb<10 UI/ml (n<35), PTH=46.5 pg/ml, 0800 h serum cortisol=12.9 μg/dl, plasmatic metanephrines=15.1 pg/ml (n<90), plasmatic normetanephrines=35.8 pg/ml (n<180). Oral glucose tolerance test showed unsuppressed GH on glucose load (nadir GH=1.710 ng/ml). Thyroid, breast, abdominal and pelvic ultrasound were normal. Bone densitometry: z-score spine=−2.5 S.D. Pituitary MRI:empty sella without pituitary microadenoma. We consider that this is either infarction of a pituitary microadenoma or ectopic secretion of GHRH requiring further evaluation.

Conclusion: ESS is a rather frequent neuroradiological finding in the general population and can be associated with hypopituitarism. GH deficiency is more common in patients with NF. Since this rare case presents a young patient with NF, ESS and an uncommon excess of GH, careful evaluation, diagnosis and follow-up appears to be essential.