Management of thyrotoxicosis occurring after surgery for Cushing's disease: a case series

Abstract

Background: Thyrotoxicosis is a rare complication of surgery for Cushing's disease (CD). In clinical practice, given the rarity of this condition, patients may be misdiagnosed, and thus not treated appropriately. This study describes the clinical features and management of thyrotoxicosis in this context. Methods: We retrospectively screened a pituitary database for CD patients who underwent surgery at Peking Union Medical College Hospital between 2010 and 2017. The electronic medical records and documentation of 732 patients were searched in order to identify instances of thyrotoxicosis. Results: Fourteen patients developed postoperative thyrotoxicosis after CD remission, representing 1.9% of all the CD patients who underwent surgery and 2.5% of the CD patients who were in remission after surgery. The onset of thyrotoxicosis occurred at a median of 3.5 months after surgery. At the onset, 13 patients (92.9%) were on a maintenance dose of hydrocortisone and were managed using a higher dose of hydrocortisone. One patient had normal adrenal function and was managed by observation first, then using anti-thyroid drugs. Thyrotoxicosis was transient in all but one patient, and lasted 1.9±0.7 months (range, 13.2 months). Conclusions: Thyrotoxicosis is a rare complication that develops during the recovery period following surgery for CD. It occurs only after the surgical resolution of hypercortisolism, and in particular alongside adrenal insufficiency during the 4 months following CD remission. Awareness of this situation should be promoted among physicians, and patients should be managed on the basis of the clinical setting and manifestation.