Abstract：
Diabetes insipidus (DI) is a group of disorders that lead to inappropriate production of large volumes of dilute urine. The three main forms are central DI (CDI), nephrogenic DI (NDI) and primary polydipsia (PP). Differentiating CDI/NDI from PP is important as patients with true DI are at risk of severe dehydration without treatment. Biochemical testing is key in the diagnosis of DI. The indirect water deprivation test (WDT) is commonly used in the investigation of DI but has drawbacks including being cumbersome and sometimes producing equivocal results. Direct measurement of AVP has theoretical advantages but has generally only been used in specialist centres. Disadvantages include the requirement to measure AVP under hypertonic stimulation and pre-analytical/analytical challenges. Copeptin (CT-proAVP) is a proxy marker for AVP that is more stable, easier to measure and has been studied more widely in recent years. Historically, the evidence supporting the diagnostic performance of these tests has been relatively poor, being based on a few small, usually single-centre studies. However more recent, well-designed prospective studies are improving the evidence base for investigation of DI. These studies have focused on the utility of copeptin measurements during stimulation tests. There is evidence that measurement of copeptin under stimulation offers improved diagnostic performance compared to the WDT. There is currently a lack of systematic, evidence-based guidelines on the diagnosis of DI, but as the quality of the evidence defining the diagnostic performance of tests for DI continues to improve, a clearer consensus on the optimal approach should become achievable.
摘要：
尿崩症（DI）是一组导致大量稀释尿液不适当产生的疾病。三种主要形式是中央DI(CDI)，肾性DI（NDI）和原发性烦渴（PP）。区分CDI/NDI与PP是重要的,因为具有真正DI的患者在未经治疗的情况下处于严重脱水的风险中。生化检测是DI诊断的关键。间接缺水测试（WDT）通常用于DI的调查，但存在缺点，包括繁琐且有时会产生模棱两可的结果。AVP的直接测量具有理论优势，但通常仅在专科中心使用。缺点包括需要在高渗刺激下测量AVP和分析前/分析挑战。和肽素（CT-proAVP）是AVP的替代标记，更稳定，更容易测量，近年来得到了更广泛的研究。历史上,支持这些测试的诊断性能的证据相对较差，基于几个小的，通常是单中心研究。然而最近，精心设计的前瞻性研究正在改善DI调查的证据基础。这些研究集中在刺激测试期间和肽素测量的实用性上。有证据表明，与WDT相比，刺激下和肽素的测量可改善诊断性能。目前缺乏系统性,基于证据的DI诊断指南，但是随着定义DI测试诊断性能的证据质量不断提高，就最佳方法达成更清晰的共识应该是可以实现的。
