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Objective: To provide an additional contribution to the differential diagnosis of Charcot-Marie-Tooth disease type 1A (CMT1A) and chronic inflammatory demyelinating polyneuropathy (CIDP) by analyzing distal duration and proximal/distal amplitude and duration ratios on different nerves in these diseases that show demyelinating peripheral neuropathy features.
Material and Methods: We retrospectively reviewed the electromyography (EMG) findings of patients aged 18-80 years who were followed up with a diagnosis of acquired and hereditary demyelinating type polyneuropathy in the neuromuscular diseases outpatient clinic in our center. We analyzed the distal CMAP duration and amplitude, proximal and distal compound muscle action potential, and duration ratios on each nerve in the patient groups, separately.
Results: The CIDP group had significantly longer Peroneal nerve distal duration than the CMT1A group (p=0.04). Median, ulnar, and tibial nerve distal durations were similar between the groups (p=0.84, p=0.86, and p=0.13, respectively). The median nerve, ulnar nerve, and peroneal nerve proximal/distal amplitude ratios were not different between the CMT1A and CIDP groups (p=0.99, p=0.38, and p=0.16, respectively). The tibial nerve proximal/distal amplitude ratio in the CIDP group was lower than in the CMT1A group (p=0.003). Median, ulnar, peroneal, and tibial nerve proximal/distal duration ratios were statistically similar among the groups (p=0.21, p=0.66, p=0.62, and p=0.46, respectively).
Conclusion: This study may help to improve the management of challenging patients where there is an overlap between hereditary and inflammatory neuropathies. The different electrodiagnostic models of various acquired and hereditary demyelinating polyneuropathies should be clinically recognized.
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2. Rajabally YA, Adams D, Latour P, Attarian S. Hereditary and inflammatory neuropathies: a review of reported associations, mimics and misdiagnoses. J Neurol Neurosurg Psychiatry. 2016;87(10):1051-60.
3. Potulska-Chromik A, Ryniewicz B, Aragon-Gawinska K, Kabzinska D, Seroka A, Lipowska M, vd. Are electrophysiological criteria useful in distinguishing childhood demyelinating neuropathies? J Peripher Nerv Syst JPNS. 2016;21(1):22-6.
4. CL, Leger JM, Nebil-Orazio E, Pollard J, Sommer C, van Doorn PA, van Schaik IN. European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) guideline on management of chronic inflammatory demyelinating polyradiculoneuropathy: report of a joint task force of the European Federation of Neurological Societies and the Peripheral Nerve Society-first revision. Eur J Neurol. 2010;17: 356-363.
5. Tankisi H, Otto M, Pugdahl K, Johnsen B, Fuglsang-Frederiksen A. Correlation between compound muscle action potential amplitude and duration in axonal and demyelinating polyneuropathy. Clin Neurophysiol Off J Int Fed Clin Neurophysiol. 2012;123(10):2099-105.
6. Daniel Dumitru, Anthony A. Amato, Machiel J. Zwarts. Electrodiagnostic medicine. Second edition. Philadelphia.2002.
7. David C. Preston, Barbara E. Shapiro. Electromiyography and neuromuscukar disorders. Clinical-electrophysiologic correlations. Second edition. Philadelphia. 2005.
8. Thaisetthawatkul P., Logigian E.L., Herrmann D.N.: Dispersion of the distal compound muscle action potential as a diagnostic criterion for chronic inflammatory demyelinating polyneuropathy. Neurology 2002; 59: pp. 1526-1532.
9. Isose S., Kuwabara S., Kokubun N., Sato Y., Mori M., Shibuya K., et. al.: The Tokyo Metropolitan Neuromuscular Electrodiagnosis Study Group. Utility of the distal compound muscle action potential duration for diagnosis of demyelinating neuropathies. J Peripher Nerv Syst 2009; 14: pp. 151-158.
10. Nodera H, Latov N, Carey B, Langsdorf J, Bedoya V, Tacheva S, Chin RL. Prolongation of the tibialis anterior duration in chronic inflammatory demyelinating polyneuropathy. Clin Neurophysiol.2012; 12382):393-398
11. Stanton M, Pannoni V, Lewis RA, Logigian EL, Naguib D, Shy ME, vd. Dispersion of compound muscle action potential in hereditary neuropathies and chronic inflammatory demyelinating polyneuropathy. Muscle Nerve. 2006;34(4):417-22.
12. Raynor EM, Ross MH, Shefner JM, Preston DC. Differentiation between axonal and demyelinating neuropathies: identical segments recorded from proximal and distal muscles. Muscle Nerve. 1995;18(4):402-8.
13. Kang JH, Kim HJ, Lee ER. Electrophysiological evaluation of chronic inflammatory demyelinating polyneuropathy and charcot-marie-tooth type 1: dispersion and correlation analysis. J Phys Ther Sci. 2013;25(10):1265-8.