A Case of Congenital Fiber Type Disproportion with Multiple Anomalies.

Seo,  Su Young; Lee,  Young Mock; Kim,  Se Hoon; Kim,  Tai Seung; Lee,  Joon Soo; Kim,  Heung Dong

Case Report

Journal of the Korean Child Neurology Society 2006;14(2):328-332.
Published online November 30, 2006.

A Case of Congenital Fiber Type Disproportion with Multiple Anomalies.

Su Young Seo, Young Mock Lee, Se Hoon Kim, Tai Seung Kim, Joon Soo Lee, Heung Dong Kim

¹Departments of Pediatrics, Institute for Handicapped Children, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea.
²Departments of Pathology, Institute for Handicapped Children, Severance Children's Hospital, Yonsei University College of Medicine, Seoul, Korea. hdkimmd@yumc.yonsei.ac.kr

Abstract

Congenital fiber type disproportion (CFTD) is a rare form of congenital myopathy characterized by the smallness and the marked predominance of type 1 fibers, which presents congenital hypotonia, delayed motor milestones, joint contractures, and skeletal deformities. The muscle biopsy reveals the type 1 fibers are more than 12% smaller than the type 2 fibers in size. We describe a 24-month-old boy who presented muscle hypotonia, delayed motor milestones, mental retardation with generalized tonic clonic seizures, and the muscle pathologic findings of CFTD. Additional findings included left cryptorchidism, congenital subluxation of the hip, contractures of ankle joints, diffuse brain atrophy, and optic nerve atrophy. We should consider CFTD as a differential diagnosis of early onset myopathy.

Key Words: Congenital fiber type disproprtion (CFTD), Congenital myopathy, Mental retardation, Seizure