ISSN 1470-3947 (print) | ISSN 1479-6848 (online)

Endocrine Abstracts (2019) 63 P674 | DOI: 10.1530/endoabs.63.P674

First and second day cortisol levels as predictors of long-term hypocortisolism after pituitary surgery

Nunzia Prencipe1, Valentina Gasco1, Filippo Gatti1, Marina Caputo2, Valentina D’Angelo1, Chiara Bona1, Mirko Parasiliti Caprino1, Alessandro Maria Berton1, Valeria Cambria1, Federica Penner3, Roberta Giordano1, Ezio Ghigo1, Francesco Zenga3 & Silvia Grottoli1

1S.C.D.U. Endocrinology, Diabetology and Metabolism, University of Turin, Turin, Italy; 2Endocrinology Department of Translational Medicine, Università del Piemonte Orientale, Novara, Italy; 3Section of Neurosurgery, Division of Neuroscience, Turin, Italy.

Introduction: Prediction of HPA (hypothalamus-pituitary-adrenal) activity after trans-sphenoidal pituitary surgery (NS) is essential for post-operative management. There is not unique behavior in this setting: most of specialists suggests 4-6 weeks of glucocorticoid supplementation and treatment interruption after demonstration of normal endogenous response. Some authors suggest early cortisol detection for the identification of patients requiring glucocorticoid therapy. Aim of study is to evaluate the ability of cortisol in first (FC) and second day (SC) after NS in predicting HPA axis function. Methods: we evaluated 71 patients (56±14.8 years old, mean±SD; 27 F) who underwent a 3D endoscopic endonasal approach to the sella between April 2013 and April 2018 in Neurosurgical Department of San Giovanni Battista Hospital for pituitary benign diseases (36 non-functioning pituitary adenoma; 20 GH-secreting; 3 PRL-secreting, 3 GH/PRL secreting, 5 FSH/LH positive and 4 Rathke cleft cysts). We excluded Cushing disease patients, those in antiallergic prophylaxis and those with hypocortisolism before surgery. For each patient we evaluated FC and SC levels (h. 8:00) after procedure and at 3 months. In all patients with cortisol levels <18 μg/dl, HPA axis was further assessed with a stimulation test (the ACTH 1 μg test or the Insulin Tolerance Test) at 3 months.

Results: None of the 71 patients had peri-procedural complications. At the discharge, 36 patients were on glucocorticoid therapy, 13 had indication to take glucocorticoid only in stress condition and 22 were dismissed without any specific therapy. At 3 months, 17 patients (23.9%) had a diagnosis of hypocortisolism (HP; 55.59±14.53 years old, F6) whilst 54 (76.1%) normal HPA activity (NP: 55.78±16.07 years old, F 21). FC levels (median; range: 25.7 μg/dl; 4.39 – 63.5 μg/dl) resulted higher than SC (15.75 μg/dl; 2.19–45 μg/dl, P<0.001). FC levels were significantly lower in HP compared with NP (P<0.02), also SC levels (HP lower than NP; P<0.001). Considering 15 μg/dl as the limit value to rule out hypocortisolism, we calculated ΔFC (FC-15) and ΔSC (SC-15). Only ΔFC resulted significantly higher in NP compared to HP (P 0.02), while no difference was detected in ΔSC (P 0.1).

Conclusion: in our study FC and SC levels have a significant strength in predicting hypocortisolism. Also ΔFC (but not in second day) could have a role in suggesting to clinicians the need of glucocorticoid treatment in patients who underwent pituitary surgery.