Terashima I

Guillain-Barrésyndrome associated with high anti-GQ1b antibody titers

Congenital hypomyelination polyneuropathy a study of two cases Sumimasa Yamashita ‘, Shota Miyake a, Michiko Yamada ‘, Hiroko Iwamoto a and Nobuko Misugi b (” Diuision of Child Neurology and b Division of Orthopedics, Kanagawa Children’s Medical Center, Yokohama, Kanagawa, Japan) This disorder was described by Lyon in 1969 for the first time, and proposed to be a new disease entity by Kennedy in 1977. We present two cases of the disorder. Case 1: A lo-year-old boy was born to healthy parents but suffered from severe neonatal asphyxia. He was discharged from hospital at the age of 3 months. He needed N-G tube feeding until the age of 1 year. His motor development was delayed in infancy. He could walk with support at the age of 3 years. He was admitted to our hospital for complete examination at 10 years of age. His intelligence was normal. He exhibited hypotonia, muscle weakness with distal dominance, total areflexia, and mild sensory disturbance. The motor nerve conduction velocity (MCV) of the median nerve was 3.0 m/s and that of the peroneal nerve was unmeasurable. Needle electrode examination revealed neurogenic muscle activities. His cerebrospinal fluid (CSF) protein level was 167.8 mg/dl. Case 2: A 6-year-old girl was born uneventfully. Her feeding, however, was poor and she was a floppy infant. She could sit alone at the age of 1 and walk with support at 2. Her mental development was normal. At age 6, her neurological status comprised hypotonia, muscle weakness with distal dominance, and total areflexia. Finger oscillation on finger to nose examination and mild sensory disturbance were also found. MCV of individual nerves was not detectable. The CSF protein level was 103.9 mg/dl. A sural nerve biopsy in both cases showed typical histological findings. An electron microscopic study revealed many large axons with very thin myelin sheaths, axons with absent myelin sheaths which were termed naked axons, and many atypical onion bulbs comprised by a concentric arrangement of double layered basement membranes without a Schwann cell cytoplasm. The fiber density of large axons was also decreased. Schwann cells formed irregular cytoplasmic processes and collagen pockets. Congenital hypomyelination polyneuropathy can be considered to be a disease entity separate from HSMN type III. The outstanding clinical feature of this condition is a nonprogressive course.