Endocrine Abstracts

Purpose: Hypopituitarism is frequently associated with lifelong replacement therapy. However, it has been suggested that recovery from hypopituitarism after transsphenoidal surgery (TSS) for pituitary adenomas may occur during follow up. The aim of this study was to assess the frequency of hypothalamus-pituitary-adrenal (HPA) axis recovery after TSS in patients with non-functioning pituitary adenomas and acromegaly.

Methods: Over the 3-year observational study-period, 146 patients underwent transsphenoidal pituitary surgery. The metyrapone test was used to assess the HPA-integrity after 1 week and after 3–12 months after TSS. The pituitary-thyroid, -gonadal and growth hormone axis were measured one week after TSS.

Results: Patients with Cushing’s disease and panhypopituitarism were excluded from the study. 44 subjects had a sufficient HPA-axis one week after surgery. 14 subjects with an insufficient HPA-axis were excluded, as the 11-deoxycortisol after metyrapone was <100 nmol/l. Eighteen patients were eligible to re-assess the HPA-integrity. In 10 out of 18 patients, insufficiency of the HPA-axis appeared to be reversible. Eight patients had persistent secondary adrenal insufficiency. The number of other pituitary hormone insufficiencies one week after TSS was associated with recovery of the HPA-axis after TSS.

Conclusion: After TSS, recovery of the HPA-axis over time does occur in a proportion of subjects. Therefore it is recommended to re-assess the HPA-integrity during follow up to prevent unnecessary glucocorticoid replacement therapy. Pituitary adenoma, reversible hypopituitarism, recovery HPA-axis, pituitary surgery, adrenal insufficiency.

Key words: Pituitary adenoma, reversible hypopituitarism, recovery HPA-axis, pituitary surgery, adrenal insufficiency.