Adaway Joanne E, Dobson Rebecca, Walsh Jennifer, Cuthbertson Daniel J, Monaghan Phillip J, Trainer Peter J, Valle Juan W, Keevil Brian G
Department of Clinical Biochemistry, University Hospital South Manchester NHS Foundation Trust, Manchester, UK The University of Manchester, Manchester Academic Health Science Centre, University Hospital South Manchester NHS Foundation Trust, Manchester, UK
Department of Obesity and Endocrinology, University Hospital Aintree and University of Liverpool, Liverpool, UK.
Ann Clin Biochem. 2016 Sep;53(Pt 5):554-60. doi: 10.1177/0004563215613109. Epub 2015 Oct 5.
Neuroendocrine tumours are slow growing tumours known to secrete a variety of vasoactive peptides which give rise to symptoms of the carcinoid syndrome. The diagnosis and monitoring of patients with neuroendocrine tumours is undertaken in many centres using 24 h urinary measurement of 5-hydroxyindoleacetic acid. However, 5-hydroxyindoleacetic acid can also be quantified in plasma and serum.
We measured 5-hydroxyindoleacetic acid concentration in 134 paired EDTA plasma and urine samples from 108 patients with known neuroendocrine tumours and 26 healthy volunteers. We also compared 5-hydroxyindoleacetic acid concentrations in paired serum and plasma samples (n = 63), then analysed paired urine and serum samples (n = 97). Furthermore, we examined the impact of renal impairment on serum 5-hydroxyindoleacetic acid by analysing 5-hydroxyindoleacetic acid in patients without neuroendocrine tumours in different stages of chronic kidney disease, as indicated by the estimated glomerular filtration rate.
Plasma and urine 5-hydroxyindoleacetic acid had very similar diagnostic sensitivities and specificities, with areas under the curve on ROC analysis of 0.917 and 0.920, respectively. Serum and plasma 5-hydroxyindoleacetic acid values showed good correlation but serum results demonstrated a positive bias, indicating the necessity for different serum and plasma reference intervals. There was an inverse correlation between estimated glomerular filtration rate and serum 5-hydroxyindoleacetic acid concentration, with 5-hydroxyindoleacetic acid increasing once the estimated glomerular filtration rate falls below 60 mL/min/1.73 m(2).
The measurement of both serum and plasma 5-hydroxyindoleacetic acid can be used for the diagnosis and monitoring of patients with neuroendocrine tumours. Provided renal function is taken into consideration, either of these tests should be incorporated into standard practice as an alternative assay to urinary 5-hydroxyindoleacetic acid.
神经内分泌肿瘤是生长缓慢的肿瘤，已知其会分泌多种血管活性肽，从而引发类癌综合征的症状。许多中心通过24小时尿液中5-羟吲哚乙酸的测定来对神经内分泌肿瘤患者进行诊断和监测。然而，血浆和血清中也可对5-羟吲哚乙酸进行定量。
我们测定了108例已知神经内分泌肿瘤患者和26名健康志愿者的134对乙二胺四乙酸（EDTA）血浆和尿液样本中的5-羟吲哚乙酸浓度。我们还比较了配对血清和血浆样本（n = 63）中的5-羟吲哚乙酸浓度，然后分析了配对尿液和血清样本（n = 97）。此外，我们通过分析不同慢性肾脏病阶段（根据估算的肾小球滤过率指示）且无神经内分泌肿瘤患者的5-羟吲哚乙酸，研究了肾功能损害对血清5-羟吲哚乙酸的影响。
血浆和尿液中的5-羟吲哚乙酸具有非常相似的诊断敏感性和特异性，在ROC分析中的曲线下面积分别为0.917和0.920。血清和血浆中的5-羟吲哚乙酸值显示出良好的相关性，但血清结果显示出正偏差，表明血清和血浆需要不同的参考区间。估算的肾小球滤过率与血清5-羟吲哚乙酸浓度呈负相关，一旦估算的肾小球滤过率降至低于60 mL/min/1.73 m²，5-羟吲哚乙酸就会升高。
血清和血浆5-羟吲哚乙酸的测定均可用于神经内分泌肿瘤患者的诊断和监测。如果考虑到肾功能，这些检测中的任何一种都应纳入标准实践，作为尿液5-羟吲哚乙酸检测的替代方法。
