Odagiri Emi, Naruse Mitsuhide, Tanabe Akiyo, Ohmura Masao, Oki Takashi, Katabami Takuyuki, Saitoh Jun, Nishika Tetsuo, Shibata Hirotaka, Doi Masaru, Hirata Yukio
Tokyo Women's Medical University, Shinjuku-ku, Tokyo.
Rinsho Byori. 2007 Jun;55(6):549-54.
Cortisol assay is used for the diagnosis of hypothalamo-pituitary adrenal disorders. The Incidence of adrenal incidentaloma has been increasing with advances in imaging tools. The criteria for the diagnosis of preclinical Cushing's syndrome in Japan was made by the Nawata group supported by the Ministry of Health and Welfare in 1995. The presence of adrenal adenoma, a lack of overt signs of Cushing's syndrome and autonomic cortisol secretion are essential for the diagnosis of preclinical Cushing's syndrome. For the diagnosis of autonomy of cortisol secretion, cortisol should not be suppressed by either low dose dexamethasone (DEX) of 1 mg (cortisol > or =3 microg/dl) or high dose DEX of 8 mg (cortisol > or =1 microg/dl). We have reported that two doses of DEX suppression tests revealed a discrepancy in several cases of adrenal incidentaloma; therefore, we studied the cortisol values of DEX suppression tests in 47 cases with adrenal incidentaloma using four different cortisol kits (TFB, SPAC, TDX and TOSOH). Correlation between the kits was good; however, correlation coefficient in the low range (< or =5 microg/dl) among kits declined. In the inter assay, discrepant results of the cortisol level were seen in six cases after 1 mg of DEX and 18 cases after 8 mg of DEX. In the intra assay, discrepant results of cortisol after 1 mg of DEX and 8 mg of DEX were seen in 31 in TFB, 23 in SPAC, 24 in TDX and 25 in TOSOH. These results revealed that the clinical diagnosis varies according to the cortisol kit used. It is suggested that standardization of the cortisol assay is necessary for the accurate diagnosis of adrenal incidentaloma.
皮质醇测定用于诊断下丘脑 - 垂体 - 肾上腺疾病。随着成像工具的进步，肾上腺偶发瘤的发病率一直在上升。1995年，在厚生省的支持下，Nawata小组制定了日本临床前库欣综合征的诊断标准。肾上腺腺瘤的存在、缺乏明显的库欣综合征体征以及自主性皮质醇分泌是临床前库欣综合征诊断的关键。对于皮质醇分泌自主性的诊断，皮质醇不应被1毫克低剂量地塞米松（DEX）（皮质醇≥3微克/分升）或8毫克高剂量DEX（皮质醇≥1微克/分升）抑制。我们曾报道，两剂量DEX抑制试验在几例肾上腺偶发瘤病例中显示出差异；因此，我们使用四种不同的皮质醇检测试剂盒（TFB、SPAC、TDX和TOSOH）研究了47例肾上腺偶发瘤患者DEX抑制试验的皮质醇值。试剂盒之间的相关性良好；然而，试剂盒之间低范围（≤5微克/分升）的相关系数下降。在批间分析中，1毫克DEX后有6例皮质醇水平结果不一致，8毫克DEX后有18例结果不一致。在批内分析中，1毫克DEX和8毫克DEX后皮质醇结果不一致的情况在TFB中有31例，SPAC中有23例，TDX中有24例，TOSOH中有25例。这些结果表明，临床诊断因所使用的皮质醇检测试剂盒而异。建议对皮质醇测定进行标准化，以准确诊断肾上腺偶发瘤。
