LAUSR

Introduction Electrodiagnostic testing (EDx) is widely used in the diagnosis of nerve and muscle diseases. The utility of EDx has mostly been studied retrospectively with varying overall compatibility rates between EDx results and clinical diagnosis reported. This study examined the diagnostic utility of EDx in the evaluation of patients with a neuromuscular disorder and compared the EDx results to the final clinical diagnosis. Methods Records from 57 consecutive patients referred to EDx on suspicion of polyneuropathy (26), motor neuron disorder (MND) (25), or myopathy (6) were prospectively analysed. The clinical follow-up diagnosis obtained from the patients’ electronic charts after 6–8 months served as diagnostic reference standard. Results The follow-up diagnosis was polyneuropathy in 16 patients, amyotrophic lateral sclerosis (ALS) in 15 patients, miscellaneous disorders in 14 patients, while 14 patients had no pathological findings. The EDx diagnosis confirmed the referral diagnosis in 30 patients (53%), suggested a new diagnosis in 13 (23%), and was normal in 14 (25%). The EDx diagnosis was confirmed by the final follow-up diagnosis in 88% of the patients and overruled in 9%. The remaining 5% was lost for follow-up. Conclusion EDx highly impacts the working diagnosis of neuromuscular disorders by providing new diagnostic information or consolidating a suspected diagnosis. In this study EDx changed the clinical referral diagnosis in almost half the patients with the EDx results validated by the long-term follow-up diagnosis in most cases.