Severe neonatal asphyxia due to X-linked centronuclear myopathy.

Severe neonatal centronuclear myopathy is inherited as an X-linked condition characterized by primary asphyxia, extreme muscular hypotonia and absent spontaneous movements. We report seven cases from three families to point out the importance of diagnosis with regard to prognosis, outcome and genetic counselling. In hypotonic diseases, analysis of cerebrospinal fluid, electromyography, nerve conduction velocity creatine kinase and a skin biopsy for fibroblast cultures for metabolic investigations are usually carried out. Needle muscle biopsy is an additional valuable investigation to establish diagnosis. In all our patients we found an increased number of centrally located nuclei with perinuclear halos confirming the diagnosis of centronuclear myopathy. The diagnosis of this disorder will become of greater importance as soon as carrier detection and prenatal diagnosis by DNA-technology are routinely available.