Sensory and Motor Peripheral Nerve Findings in Patients with Diabetes Mellitus Referred for Electrodiagnosis

Abstract

Background: Diabetes mellitus (DM) is the most prevalent endocrine disease and the most common cause of peripheral neuropathy, which is one of the important long-term complications of diabetes. Careful neurologic examination and electrodiagnosis are essential and valuable to the early diagnosis of neuropathy and prevention of its consequences. The aim of this study was to assess electroneurographic findings in patients with diabetes.

Methods: This study was conducted on 103 randomly selected patients with diabetes who referred for electroneurographic studies. Neurologic and electroneurographic examination were performed in all patients. Moreover, 3 motor nerves (M-median, deep peroneal, and tibial) and 3 sensory nerves (S-median, sural and superficial peroneal) were evaluated and in each nerve its conduction velocity, distal latency, and amplitude were assessed. Furthermore, bilateral H-reflex was measured in the soleus muscle.

Results: Among the 103 studied subjects, 30 patients (29.1%) had type I DM and 73 (70.9%) had type II DM. The overall incidence of diabetic neuropathy was 79.6%. There was a direct correlation between disease duration and prevalence of diabetic neuropathy. The most common complaint was numbness and tingling of distal parts (72.0%) (P < 0.0001). The most common physical finding was abnormal ankle jerk (94.0%) (P < 0.0010). The most sensitive finding in electroneurographic examination was absent or prolonged H-reflex (92.5%) (P < 0.0001). Overall, the amplitude was a more sensitive parameter than distal latency.

Conclusion: Nerve conduction parameters especially H-reflex study and amplitude of sensory responses are valuable in the early diagnosis of diabetic neuropathy. There is a good correlation between clinical and electroneurographic findings; thus, clinical examination is highly recommended in order to prevent unnecessary work-ups, and help prevent untoward complications.