Al-Shekhlee Amer, Robinson Jenice, Katirji Bashar
The Neurologic Institute, University Hospitals of Cleveland, Case School of Medicine, Cleveland, Ohio 44106-5040, USA.
Muscle Nerve. 2007 Feb;35(2):246-50. doi: 10.1002/mus.20660.
The relative preservation (sparing) of sural sensory nerve action potentials (SNAPs) is a useful diagnostic finding in patients with acute inflammatory demyelinating polyneuropathy (AIDP). However, recording of sural SNAPs is not always technically feasible, especially in obese, edematous, or elderly individuals. Hence, we systematically evaluated the predictive values of the commonly employed SNAPs in the diagnosis of AIDP within 2 weeks from onset of symptoms. Sensory sparing patterns and sensory ratios of the sural, radial, median, and ulnar SNAPs of AIDP patients were included in a retrospective and blinded analysis, and compared to patients with diabetic polyneuropathy (DPN) and controls. Logistic regression models for the sural plus radial SNAPs/median plus ulnar SNAPs (sensory ratio) were constructed. A sural sparing pattern was present only in the AIDP group (34.4%, P < 0.001). A radial sparing pattern did not discriminate the AIDP from the DPN groups. The sural/radial sensory ratio was useful to ascertain DPN, but did not discriminate AIDP from controls. The sensory ratio was higher in AIDP compared to DPN and controls and was an independent predictor for AIDP. This study implies that the sensory ratio is a useful predictor for the diagnosis of AIDP and may substitute for sural sparing in technically difficult situations.
腓肠感觉神经动作电位（SNAPs）相对保留（ spared ）是急性炎症性脱髓鞘性多发性神经病（AIDP）患者一项有用的诊断发现。然而，记录腓肠SNAPs在技术上并不总是可行的，尤其是在肥胖、水肿或老年个体中。因此，我们系统评估了发病2周内常用SNAPs对AIDP诊断的预测价值。将AIDP患者腓肠、桡、正中及尺神经SNAPs的感觉保留模式和感觉比率纳入回顾性盲法分析，并与糖尿病性多发性神经病（DPN）患者及对照组进行比较。构建了腓肠加桡神经SNAPs/正中加尺神经SNAPs（感觉比率）的逻辑回归模型。仅在AIDP组出现腓肠神经保留模式（34.4%，P<0.001）。桡神经保留模式不能区分AIDP组和DPN组。腓肠/桡感觉比率有助于确诊DPN，但不能区分AIDP组和对照组。AIDP组的感觉比率高于DPN组和对照组，是AIDP的独立预测指标。本研究表明，感觉比率是AIDP诊断的有用预测指标，在技术困难的情况下可替代腓肠神经保留情况。
