A female newborn delivered at 32 weeks of gestation presented with multiple joint
contractures consistent with arthrogryposis multiplex congenita (AMC). The girl died
after a four days course of severe respiratory distress. Autopsy revealed slightly
hypoplastic and immature lungs with acute necrotizing bronchopneumonia, and marked
consecutive hypoxic brain lesions with severe periventricular haemorrhages. The peripheral
nerves including the cranial and spinal nerve roots showed a hypomyelination radiculoneuropathy
with well preserved axons and a normal content of Schwann cells. In the skeletal muscles
of the arms and legs some fascicles of the extensors were replaced by lipomatous tissue.
Since myelination of the white matter in the central nervous system was adequate to
the age, this case represents an exclusive maturation disorder of the peripheral myelin
sheaths that may be considered causal for AMC.
Arthrogryposis multiplex congenita - Polyradiculoneuropathy - Hypomyelination
