Kim Hee Kyung, Yoon Jee Hee, Jeong Yun Ah, Kang Ho Cheol
Department of Internal Medicine, Chonnam National University Medical School, Gwangju, Korea.
Endocrinol Metab (Seoul). 2016 Dec;31(4):592-597. doi: 10.3803/EnM.2016.31.4.592.
In subclinical Cushing syndrome (SC), it is assumed that glucocorticoid production is insufficient to cause a clinically recognizable syndrome. Differences in hormonal levels or recovery time of the hypothalamic-pituitary-adrenocortical (HPA) axis after adrenalectomy between patients with overt Cushing syndrome (OC) and SC remain unknown.
Thirty-six patients (10 with OC and 26 with SC) with adrenal Cushing syndrome who underwent adrenalectomy from 2004 to 2014 were reviewed retrospectively. Patients were treated with glucocorticoid after adrenalectomy and were reevaluated every 1 to 6 months using a rapid adrenocorticotropic hormone (ACTH) stimulation test.
Levels of basal 24-hour urine free cortisol (UFC), serum cortisol after an overnight dexamethasone suppression test (DST), and serum cortisol and 24-hour UFC after low-dose DST and high-dose DST were all significantly lower in patients with SC compared with OC. Basal ACTH levels showed significantly higher in patients with SC compared with OC. The probability of recovering adrenal function during follow-up differed significantly between patients with OC and SC (P=0.001), with significant correlations with the degree of preoperative cortisol excess. Patients with OC required a longer duration of glucocorticoid replacement to recover a normal ACTH stimulation test compared with patients with SC (median 17.0 months vs. 4.0 months, P<0.001).
The HPA axis recovery time after adrenalectomy in patients with SC is rapid and is dependent on the degree of cortisol excess. More precise definition of SC is necessary to achieve a better management of patients and to avoid the risk of under- or over-treatment of SC patients.
在亚临床库欣综合征（SC）中，假定糖皮质激素的分泌量不足以引发临床上可识别的综合征。显性库欣综合征（OC）患者与SC患者在肾上腺切除术后下丘脑-垂体-肾上腺皮质（HPA）轴的激素水平或恢复时间的差异尚不清楚。
回顾性分析了2004年至2014年间接受肾上腺切除术的36例肾上腺库欣综合征患者（10例OC患者和26例SC患者）。患者在肾上腺切除术后接受糖皮质激素治疗，并使用快速促肾上腺皮质激素（ACTH）刺激试验每1至6个月进行一次重新评估。
与OC患者相比，SC患者的基础24小时尿游离皮质醇（UFC）水平、过夜地塞米松抑制试验（DST）后的血清皮质醇水平、低剂量DST和高剂量DST后的血清皮质醇和24小时UFC水平均显著降低。与OC患者相比，SC患者的基础ACTH水平显著更高。OC患者和SC患者在随访期间肾上腺功能恢复的概率差异显著（P = 0.001），与术前皮质醇过量程度显著相关。与SC患者相比，OC患者需要更长时间的糖皮质激素替代治疗才能使ACTH刺激试验恢复正常（中位数17.0个月对4.0个月，P < 0.001）。
SC患者肾上腺切除术后HPA轴的恢复时间较快，且取决于皮质醇过量的程度。为了更好地管理患者并避免SC患者治疗不足或过度治疗的风险，有必要对SC进行更精确的定义。
