Diagnostic accuracy of an identification tool for localized neuropathic pain based on the IASP criteria

Objective: Based on the clear neuroanatomical delineation of many neuropathic pain (NP) symptoms, a simple tool for performing a short structured clinical encounter based on the IASP diagnostic criteria was developed to identify NP. This study evaluated its accuracy and usefulness. Methods: A case-control study was performed in 19 pain clinics within Spain. A pain clinician used the experimental screening tool (the index test, IT) to assign the descriptions of non-neuropathic (nNP), non-localized neuropathic (nLNP), and localized neuropathic (LNP) to the patients’ pain conditions. The reference standard was a formal clinical diagnosis provided by another pain clinician. The accuracy of the IT was compared with that of the Douleur Neuropathique en 4 questions (DN4) and the Leeds Assessment of Neuropathic Signs and Symptoms (LANSS). Results: Six-hundred and sixty-six patients were analyzed. There was a good agreement between the IT and the reference standard (kappa =0.722). The IT was accurate in distinguishing between LNP and nLNP (83.2% sensitivity, 88.2% specificity), between LNP and the other pain categories (nLNP + nNP) (80.0% sensitivity, 90.7% specificity), and between NP and nNP (95.5% sensitivity, 89.1% specificity). The accuracy in distinguishing between NP and nNP was comparable with that of the DN4 and the LANSS. The IT took a median of 10 min to complete. Conclusions: A novel instrument based on an operationalization of the IASP criteria can not only discern between LNP and nLNP, but also provide a high level of diagnostic certainty about the presence of NP after a short clinical encounter.研究目的：基于众多神经性疼痛（neuropathic pain, NP）症状明确的神经解剖学划分，本研究开发了一款基于国际疼痛研究协会（International Association for the Study of Pain, IASP）诊断标准的简短结构化临床问诊简易工具，用于识别神经性疼痛。本研究对该工具的诊断准确性与临床实用性进行了评估。研究方法：在西班牙境内的19家疼痛专科诊所开展了一项病例对照研究。疼痛科医师使用本实验性筛查工具（即指标测试，index test, IT）对患者的疼痛状况进行分类，将其划分为非神经性疼痛（non-neuropathic, nNP）、非局限性神经性疼痛（non-localized neuropathic, nLNP）以及局限性神经性疼痛（localized neuropathic, LNP）。参照标准为另一名疼痛科医师作出的正式临床诊断。将该指标测试的诊断准确性与Douleur Neuropathique en 4 questions（DN4）量表以及利兹神经性疼痛体征与症状评估量表（Leeds Assessment of Neuropathic Signs and Symptoms, LANSS）进行了对比。研究结果：本研究共纳入666例患者进行数据分析。指标测试与参照标准之间具有良好的一致性（kappa值=0.722）。该工具在区分局限性神经性疼痛与非局限性神经性疼痛（灵敏度83.2%，特异度88.2%）、局限性神经性疼痛与其余疼痛类别（非局限性神经性疼痛+非神经性疼痛）（灵敏度80.0%，特异度90.7%），以及神经性疼痛与非神经性疼痛（灵敏度95.5%，特异度89.1%）时均表现出良好的准确性。该工具在区分神经性疼痛与非神经性疼痛方面的准确性与DN4量表及LANSS量表相当。完成该指标测试所需的中位时间为10分钟。研究结论：一款基于IASP诊断标准操作化的新型工具，不仅能够有效区分局限性神经性疼痛与非局限性神经性疼痛，还可在简短的临床问诊后对神经性疼痛的存在提供较高水平的诊断确定性。