Névoret Marie-Laure, Vinik Aaron I
Impeto Medical, Inc., San Diego, CA.
Eastern Virginia Medical School, Norfolk, VA.
J Diabetes Complications. 2015 Mar;29(2):313-7. doi: 10.1016/j.jdiacomp.2014.10.012. Epub 2014 Nov 6.
Chronic inflammatory demyelinating polyneuropathy (CIDP) is eleven times more common among people with diabetes than the general population and is treatable with appropriate immunotherapy. Treatment response is usually measured clinically (symptomatic and functional improvement). We present a case of a patient with type 2 diabetes (T2D) and CIDP whose treatment response was measurable with the Sudoscan sudomotor function test. This test may represent a new objective evaluation of the treatment of CIDP.
The patient is a 60year old male initially referred to our center in August 2012, at which time he was diagnosed with CIDP based on AAN electrodiagnostic criteria (NCS). Autonomic functions were significant for low heart rate variability response to expiration/inspiration (E/I), Valsalva maneuver and the ratio of the RR interval for the 30th to the 15th beat upon standing (1.08, 1.12, 1.05 respectively), and frequency analysis of the total spectral power, the standard deviation of the normal RR intervals (sdNN) and their root mean squared (rmsSD). Sudoscan electrochemical skin conductances (ESC), measuring small nerve fiber function on the palms and soles, were very low: 23 μS in the feet and 32 μS in the hands. After one cycle of intravenous immunoglobulin (IVIG: 6 doses total, 75g each) the patient had no change in symptoms of burning, numbness, shooting pains, and gait impairment. However, E/I, Valsalva, and 30:15 ratios (1.19, 1.36, 1.39 respectively) were improved, as were NCS. Sudoscan scores for feet and hands were unchanged (23 μS and 32 μS). In March 2013, the patient's autonomic functions worsened (E/I, Valsalva, and 30:15 ratios 1.1, 1.07, 1.12 respectively), but feet and hand ESC started to show improvement (35 μS and 52 μS respectively). Azathioprine was started. Eight days after a second cycle of IVIG in January 2014, the patient reported for the first time less burning, shooting pains and tingling. E/I, Valsalva, and 30:15 ratios remained low (1.03, 1.07, and not analyzable, respectively), while foot and hand ESC scores continued to improve (43 μS and 55 μS respectively).
CIDP diagnosis and treatment response are difficult in the diabetic patient. We found that NCS and autonomic function tests did not correlate well with clinical status while numerical Sudoscan scores matched closely symptomatic changes. ESC have been found to correlate well with peripheral small fiber function and neuropathic symptoms in DPN. The findings in this patient warrant further investigation of the use of Sudoscan to monitor CIDP response to therapy.
慢性炎症性脱髓鞘性多发性神经病（CIDP）在糖尿病患者中的发病率是普通人群的11倍，可通过适当的免疫疗法进行治疗。治疗反应通常通过临床方法进行衡量（症状和功能改善）。我们报告了一例2型糖尿病（T2D）合并CIDP的患者，其治疗反应可通过Sudoscan汗腺运动功能测试进行测量。该测试可能代表了一种对CIDP治疗的新的客观评估方法。
该患者为60岁男性，于2012年8月首次转诊至我们中心，当时根据美国神经病学学会（AAN）的电诊断标准（神经传导速度测定）被诊断为CIDP。自主神经功能表现为对呼气/吸气（E/I）、瓦尔萨尔瓦动作以及站立时第30次与第15次心跳的RR间期比值（分别为1.08、1.12、1.05）的心率变异性反应较低，以及对总频谱功率、正常RR间期的标准差（sdNN）及其均方根（rmsSD）的频率分析。Sudoscan电化学皮肤电导率（ESC）用于测量手掌和脚底的小神经纤维功能，数值非常低：足部为23μS，手部为32μS。在进行一个周期的静脉注射免疫球蛋白（IVIG：共6剂，每剂75g）治疗后，患者的灼痛、麻木、刺痛和步态障碍症状没有变化。然而，E/I、瓦尔萨尔瓦动作以及30:15比值（分别为1.19、1.36、1.39）有所改善，神经传导速度测定结果也是如此。足部和手部的Sudoscan评分没有变化（分别为23μS和32μS）。2013年3月，患者的自主神经功能恶化（E/I、瓦尔萨尔瓦动作以及30:15比值分别为1.1、1.07、1.12），但足部和手部的ESC开始显示改善（分别为35μS和52μS）。开始使用硫唑嘌呤。在2014年1月进行第二个周期的IVIG治疗八天后，患者首次报告灼痛、刺痛和刺痛感减轻。E/I、瓦尔萨尔瓦动作以及30:15比值仍然较低（分别为1.03、1.07，且30:15比值无法分析），而足部和手部的ESC评分继续改善（分别为43μS和55μS）。
糖尿病患者的CIDP诊断和治疗反应较为困难。我们发现神经传导速度测定和自主神经功能测试与临床状态的相关性不佳，而Sudoscan的数值评分与症状变化密切匹配。ESC已被发现与糖尿病周围神经病变（DPN）中的外周小纤维功能和神经病变症状密切相关。该患者的研究结果值得进一步研究使用Sudoscan来监测CIDP对治疗的反应。
