Chang J F, Jong Y J, Mak S C, Chiang C H
Department of Pediatrics, Kaohsiung Medical College, Taiwan, R.O.C.
Zhonghua Min Guo Xiao Er Ke Yi Xue Hui Za Zhi. 1990 Nov-Dec;31(6):366-72.
Congenital fiber type disproportion (CFTD) is described clinically as muscle weakness and hypotonia with delayed motor development, usually from infancy. Muscle biopsy reveals that type 1 fibers predominate and smaller than type 2 fibers by a margin greater than 12% of the diameter of the type 2 fibers. There are no other subcellular abnormalities, and generally prognosis is good. The CFTD case is a six-month-old girl who manifested clinically as a floppy infant. A biopsied specimen from the left biceps brachii muscle revealed type 1 fiber predominance and hypoplasia with an increased number of undifferentiated type 2C fibers. Electromyogram, nerve conduction velocity and serum creatine kinase level were normal. The child learned to walk without assistance at 1 year 7 month old. Now 2-years and 10-months old, she can climb stairs without difficulty, although she cannot run fast.
先天性纤维类型比例失调（CFTD）在临床上表现为肌肉无力和肌张力减退，伴有运动发育迟缓，通常始于婴儿期。肌肉活检显示1型纤维占主导，且比2型纤维小，其直径差异大于2型纤维直径的12%。不存在其他亚细胞异常，总体预后良好。该CFTD病例为一名6个月大的女孩，临床上表现为软弱无力的婴儿。左肱二头肌活检标本显示1型纤维占主导且发育不全，未分化的2C型纤维数量增加。肌电图、神经传导速度和血清肌酸激酶水平均正常。该患儿在1岁7个月时学会了独立行走。现在2岁10个月大，她可以轻松爬楼梯，不过跑不快。
