Development and Validation of a 0.5 mg Dexamethasone Suppression Test as an Initial Screening Test for the Diagnosis of ACTH-dependent Cushing’s Syndrome

Endocrine Journal

Kozo HASHIMOTO³  Masaru DOI⁴  Yukio HIRATA⁴  Toshihiro SUDA²  Satoru SAKIHARA²  Yasumasa IWASAKI³  Kazunori KAGEYAMA²  Yutaka OKI¹  Takeshi NIGAWARA² 

[1] Second Division, Department of Medicine, Hamamatsu University School of Medicine, Shizuoka, Japan;Department of Endocrinology and Metabolism, Hirosaki University Graduate School of Medicine, Aomori, Japan;Department of Endocrinology, Metabolism and Nephrology, Kochi Medical School, Kochi University, Kochi, Japan;Department of Clinical and Molecular Endocrinology, Tokyo Medical and Dental University Graduate School, Tokyo, Japan

关键词: ACTH-dependent Cushing’s syndrome;    Cushing’s disease;    Dexamethasone suppression test;    Screening;   

DOI  :  10.1507/endocrj.K09E-194

学科分类：内分泌与代谢学

来源: Japan Endocrine Society

【 摘 要 】

References(34)Cited-By(6)For the diagnosis of Cushing’ s syndrome (CS), the overnight 1 mg dexamethasone suppression test (DST) has been widely used as a standard low-dose DST. However, it is evident that 1 mg DST may not be sensitive enough to detect CS when the cortisol cut-off concentration is 5 μg/dL. Therefore, we developed and validated 0.5 mg DST as a new screening method for diagnosis of ACTH-dependent CS. To compare 0.5 mg DST with 1 mg DST, 110 patients with ACTHdependent CS were enrolled, including 88 with Cushing’ s disease (CD), 8 with subclinical CD and 14 with ectopic ACTH syndrome, as well as 134 control subjects. Subjects were given either 0.5 mg or 1 mg dexamethasone orally at 23:00 on different days, with blood samples collected the following morning between 8:00 and 9:00 to determine plasma cortisol concentration. The area under the receiver operator characteristics curve observing the 0.5 mg DST was higher than that of the 1 mg DST. The most sensitive and specific cut-off value of plasma cortisol concentration using 0.5 mg DST was found to be 3.05 μg/dL with 99.1% sensitivity and 98.4% specificity, identical to the 3 μg/dL cut-off currently used in the Japanese guideline for diagnosis of subclinical CD. In conclusion, 0.5 mg DST is a sensitive and specific screening test for diagnosis of ACTH-dependent CS. We recommend 0.5 mg DST with a cortisol cut-off concentration of 3 μg/dL to be used as the initial step in diagnosing ACTH-dependent CS.

【 授权许可】

Unknown