Forstenpointner Julia, Ruscheweyh Ruth, Attal Nadine, Baron Ralf, Bouhassira Didier, Enax-Krumova Elena K, Finnerup Nanna B, Freynhagen Rainer, Gierthmühlen Janne, Hansson Per, Jensen Troels S, Maier Christoph, Rice Andrew S C, Segerdahl Märta, Tölle Thomas, Treede Rolf-Detlef, Vollert Jan
Division of Neurological Pain Research and Therapy, Department of Neurology, Universitätsklinikum Schleswig-Holstein, Campus Kiel, Germany.
Department of Neurology, Ludwig-Maximilians-University Hospital, Munich, Germany.
Pain. 2021 Mar 1;162(3):718-727. doi: 10.1097/j.pain.0000000000002058.
The pathophysiology of pain in neuropathy is complex and may be linked to sensory phenotypes. Quantitative sensory testing, a standardized method to evaluate sensory profiles in response to defined stimuli, assesses functional integrity of small and large nerve fiber afferents and central somatosensory pathways. It has revealed detailed insights into mechanisms of neuropathy, yet it remains unclear if pain directly affects sensory profiles. The main objective of this study was to investigate sensory profiles in patients with various neuropathic conditions, including polyneuropathy, mononeuropathy, and lesions to the central nervous system, in relation to self-reported presence or absence of pain and pain sensitivity using the Pain Sensitivity Questionnaire. A total of 443 patients (332 painful and 111 painless) and 112 healthy participants were investigated. Overall, loss of sensation was equally prevalent in patients with and without spontaneous pain. Pain thresholds were equally lowered in both patient groups, demonstrating that hyperalgesia and allodynia are just as present in patients not reporting any pain. Remarkably, this was similar for dynamic mechanical allodynia. Hypoalgesia was more pronounced in painful polyneuropathy, whereas hyperalgesia was more frequent in painful mononeuropathy (compared with painless conditions). Self-reported pain sensitivity was significantly higher in painful than in painless neuropathic conditions. Our results reveal the presence of hyperalgesia and allodynia in patients with central and peripheral lesions of the somatosensory system not reporting spontaneous pain. This shows that symptoms and signs of hypersensitivity may not necessarily coincide and that painful and painless neuropathic conditions may mechanistically blend into one another.
神经病变中疼痛的病理生理学很复杂，可能与感觉表型有关。定量感觉测试是一种评估对特定刺激的感觉特征的标准化方法，可评估小神经纤维和大神经纤维传入以及中枢体感通路的功能完整性。它揭示了神经病变机制的详细见解，但疼痛是否直接影响感觉特征仍不清楚。本研究的主要目的是使用疼痛敏感性问卷，调查各种神经病变患者（包括多发性神经病、单神经病和中枢神经系统病变）的感觉特征，以及自我报告的疼痛存在与否和疼痛敏感性。共调查了443例患者（332例有疼痛，111例无疼痛）和112名健康参与者。总体而言，有和无自发痛的患者中感觉丧失的发生率相同。两组患者的疼痛阈值均同样降低，表明痛觉过敏和异常性疼痛在未报告任何疼痛的患者中同样存在。值得注意的是，动态机械性异常性疼痛也是如此。痛觉减退在疼痛性多发性神经病中更明显，而痛觉过敏在疼痛性单神经病中更常见（与无痛情况相比）。自我报告的疼痛敏感性在疼痛性神经病变患者中显著高于无痛性神经病变患者。我们的结果显示，在未报告自发痛的体感系统中枢和外周病变患者中存在痛觉过敏和异常性疼痛。这表明超敏反应的症状和体征不一定同时出现，疼痛性和无痛性神经病变情况在机制上可能相互交融。
