Wear Referrals Veterinary Hospital, Bradbury, Stockton-on-Tees, UK.
School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, UK.
J Am Vet Med Assoc. 2022 Oct 25;261(1):111-117. doi: 10.2460/javma.22.08.0346.
To assess the diagnostic performance of a benchtop fluorescent enzyme immunoassay analyzer (AIA-360; Tosoh Bioscience Inc) for the measurement of serum cortisol concentration as a screening test for hypoadrenocorticism in dogs.
173 client-owned dogs (20 with hypoadrenocorticism and 153 with nonadrenal illness).
Medical records of all dogs that underwent an ACTH stimulation test between June 2015 and October 2019 were reviewed retrospectively. Dogs were excluded if the ACTH stimulation test was performed on the basis of a suspicion of hypercortisolism, serum cortisol concentrations were measured using an analyzer other than the one assessed in the present study, or dogs had received medication known to affect the pituitary-adrenal axis in the 4 weeks1,2 preceding ACTH stimulation testing. The diagnostic performance of the benchtop analyzer was evaluated by calculating sensitivity, specificity, and likelihood ratios at various cutoff points.
Serum resting cortisol cutoff point concentrations of 0.8 μg/dL (22 nmol/L), 1 μg/dL (28 nmol/L), and 2 μg/dL (55 nmol/L) had a sensitivity of 100%. An optimal serum resting cortisol cutoff point of 0.58 μg/dL (16 nmol/L) had a sensitivity, specificity, and positive and negative likelihood ratios of 100%, 97%, and 30.6 and 0.0, respectively.
Findings indicated that previously derived cutoff points could be used with excellent sensitivity to exclude hypoadrenocorticism in this population of dogs when serum cortisol concentration was measured with the evaluated benchtop analyzer. An ACTH stimulation test may need to only be performed to diagnose hypoadrenocorticism if resting serum cortisol concentration is ≤ 0.58 μg/dL when measured with the evaluated benchtop analyzer.
评估台式荧光酶免疫分析仪（AIA-360；Tosoh Bioscience Inc）测量血清皮质醇浓度作为犬肾上腺皮质功能减退症筛查试验的诊断性能。
173 只患畜犬（20 只为肾上腺皮质功能减退症，153 只为非肾上腺疾病）。
回顾性分析 2015 年 6 月至 2019 年 10 月间接受 ACTH 刺激试验的所有犬的病历。如果 ACTH 刺激试验是基于怀疑皮质醇过多、使用本研究中未评估的分析仪测量血清皮质醇浓度、或在 ACTH 刺激试验前 4 周内使用已知影响垂体-肾上腺轴的药物，则将排除这些犬。通过计算不同临界值的敏感性、特异性和似然比来评估台式分析仪的诊断性能。
血清基础皮质醇临界值浓度为 0.8μg/dL（22nmol/L）、1μg/dL（28nmol/L）和 2μg/dL（55nmol/L）时，敏感性为 100%。血清基础皮质醇最佳临界值为 0.58μg/dL（16nmol/L），其敏感性、特异性、阳性和阴性似然比分别为 100%、97%、30.6 和 0.0。
结果表明，当使用评估的台式分析仪测量血清皮质醇浓度时，以前得出的临界值可用于排除该犬种人群的肾上腺皮质功能减退症，具有极佳的敏感性。如果使用评估的台式分析仪测量时血清基础皮质醇浓度≤0.58μg/dL，则可能仅需进行 ACTH 刺激试验以诊断肾上腺皮质功能减退症。
