Wilcox P G, Stein H B, Clarke S D, Paré P D, Pardy R L
University of British Columbia Pulmonary Research Laboratory, Vancouver, Canada.
Chest. 1988 Feb;93(2):352-8. doi: 10.1378/chest.93.2.352.
Diaphragmatic weakness has been identified as one of the pulmonary manifestations of systemic lupus erythematosus. Whether this weakness results from a neuropathic or myopathic process has not been established. Thirty patients with SLE were screened for the presence of inspiratory muscle (IM) weakness. Detailed studies were performed in nine with IM weakness. All nine were found to have diaphragmatic weakness (mean +/- SD, maximal transdiaphragmatic pressure 50 +/- 12 cmH2O). Phrenic nerve latencies, evaluated using transcutaneous stimulation, were normal in all individuals excluding a demyelinating neuropathy. Compound diaphragm action potential (CDAP) with phrenic nerve stimulation was normal in six of these nine patients. Reduced CDAP in three of nine patients was consistent either with axonal degeneration of the phrenic nerve or diaphragm myopathy. Nerve conduction and electromyographic studies on peripheral nerves and muscles respectively failed to demonstrate an associated generalized neuropathy or myopathy. We conclude that diaphragmatic weakness in patients with SLE is both common and is very unlikely to be caused by a phrenic neuropathy.
膈肌无力已被确认为系统性红斑狼疮的肺部表现之一。这种无力是由神经病变还是肌病过程引起的尚未确定。对30例系统性红斑狼疮患者进行了吸气肌（IM）无力的筛查。对9例有IM无力的患者进行了详细研究。发现所有9例均有膈肌无力（平均±标准差，最大跨膈压50±12 cmH2O）。使用经皮刺激评估的膈神经潜伏期在所有个体中均正常，排除了脱髓鞘性神经病变。这9例患者中有6例膈神经刺激时复合膈肌动作电位（CDAP）正常。9例患者中有3例CDAP降低，这与膈神经轴索性变性或膈肌肌病一致。分别对外周神经和肌肉进行的神经传导和肌电图研究未能证实存在相关的全身性神经病变或肌病。我们得出结论，系统性红斑狼疮患者的膈肌无力很常见且极不可能由膈神经病变引起。
