Endocrine Abstracts

It is well known that successful treatment of Cushing’s syndrome (CS) leads to transient adrenal insufficiency due to suppression of the hypothalamo–pituitary–adrenal (HPA) axis by the long-standing cortisol excess. Reports on HPA recovery in recent years including CS patients with less florid clinical features are scarce. Herein we report our findings in a series of patients with various forms of CS successfully treated in our department over the last 15 years.

We studied 59 patients with CS (11 men, 48 women, mean age 44.1±1.51 years) who underwent curative surgical resection: 20 had Cushing’s disease (CD), 34 adrenal adenomas (AA), and, five ectopic ACTH secretion (EAS). Cure was documented by low postoperative morning serum cortisol levels. Each patient received hydrocortisone replacement after surgery and was re-evaluated every 3–6 months with an ACTH stimulation test (250 μg Synacthen). Patients were also monitored carefully for symptoms and signs of adrenal insufficiency. Mean follow-up time from cure was 54.7±9.99 months. At the latest follow-up HPA axis has recovered in 33 patients (55.9%) while in 26 was still suppressed. The former group had significantly longer follow-up period (75.4±16.30 vs 28.5±6.7, P=0.0011). The mean time of HPA axis recovery was 23.4±3.2 months. At latest follow-up, HPA recovery was noted in 60% of CD, 50% of AA, and 80% of EAS patients. There was no correlation whatsoever between pretreatment morning ACTH/F/DHEAS, midnight F and UFC levels with the time-length of HPA suppression in the whole patient group, as well as in the subgroups of CD and AA patients.

In conclusion HPA axis recovery of patients with various forms of CS still requires a substantial time-length after the successful treatment of hypercotisolism. Pretreatment hormonal levels do not correlate with this time-length.