Clinical and pathological differences in common subtypes of Charcot-Marie-Tooth disease / 中华神经科杂志

ABSTRACT

Objective To analyze the differences of the clinical and neuropathological features among the common Charcot-Marie-Tooth disease (CMT) subtypes.Methods There were 81 CMT patients confirmed by genetic testing from 2005 to 2015 in Department of Neurology,Peking University First Hospital,including 31 cases of CMT1A (38.3％),19 cases of CMTX1 (23.5％),16 cases of CMT2A2 (19.8％) and 15 cases of 9 rare types of CMT (1.2％-4.9％).We compared the onset age,duration,muscles weakness of legs,frequency of pes cavus,and main pathological changes of the sural nerve biopsy in 48 cases of the common CMT subtypes.Results The mean age of the onset was (12.00 ± 6.77) years in CMT1A patients,(11.81 ±4.65) years in CMTX1 patients and (5.00 ±2.68) years in CMT2A2 patients (Brown-Forsythe test,P =0.001).The duration was (12.00 ± 6.75) years in CMT1A patients,(8.50 ± 4.75) years in CMTX1 patients and (5.00 ± 2.73) years in CMT2A2 patients (Brown-Forsythe test,P =0.001).The muscle force of the dorsi flexors was Ⅳ (0,Ⅴ) in CMT1A patients,Ⅲ + (0,Ⅳ) in CMTX1 patients and 0 (0,Ⅳ) in CMT2A2 patients (H =11.359,P =0.020).The pes cavus appeared in 15/23 cases of CMT1A,10/16 cases of CMTX1 and 1/9 cases of CMT2A2 (Fisher test,P=0.017).The leukoencephalopathy appeared only in 3 cases of CMTX1 and the visual loss appeared only in 3 cases of CMT2A2.The onion-bulb formations of myelinated fibers appeared in 23/23 cases of CMT1 A,5/16 cases of CMTX1 and 2/9 cases of CMT2A2(Fisher test,P =0.000).The axonal regeneration appeared in 16/23 cases of CMT1A,16/16 cases of CMTX1 and 9/9 cases of CMT2A2 (x2 =7.666,P =0.016).There were significant differences among the three common CMT subtypes in the above parameters.Conclusions CMT1A,CMT2A2 and CMTX1 are the most common subtypes of CMT in the present study.For the clinical diagnosis,more attention should be paid to the onset of the disease,duration,muscles weakness,pes cavus,cerebral symptoms and visual loss.The present frequency of onion-bulb and the axonal regeneration of myelinated fibers help the different pathological diagnosis among them.