Central Core Disease (CCD)

The first ENMC workshop on central core disease (CCD) was held in Hilversum on 19th and 20th January 2001. Seventeen participants from Belgium, France, Germany and the United Kingdom attended this meeting. (The participants covered the various specialties working on central core disease: neurologists, paediatric neurologists, neuropathologists, geneticists, a physiopathologist and an anaesthesiologist). Central core disease is a congenital myopathy, clinically characterized by generalized muscle weakness and morphologically defined by the presence of cores on staining for oxidative enzymes. Autosomal dominant inheritance is highly predominant. However, several sporadic cases have been presented at the workshop. Clear autosomal recessive inheritance has not been reported yet. The association with malignant hyperthermia susceptibility, a well-established characteristic in this disease, has been reviewed. In asymptomatic individuals with malignant hyperthermia susceptibility, confirmed by an in vitro contracture test, core lesions as well as type 1 fibre predominance are occasionally visualized. It was agreed not to diagnose 'central core disease' in these subjects however, because of the absence of a clinical correlate. Linkage to the ryanodine receptor gene (RYR1) on chromosome 19q was demonstrated some 10 years ago. Recently, several RYR1 mutations, cosegretating with clinical and/or histological findings have been identified. A detailed update of available genetic data was realized. The importance of longitudinal sections, electron microscopy and possibly immunocytochemistry has been stressed especially to distinguish central cores from minicores. The guidelines for the diagnosis of central core disease, defined at a previous ENMC workshop on congenital myopathies, were reconsidered and revised, providing inclusion and exclusion criteria for forthcoming collaborative genetic studies. All centres present agreed upon collaborative projects e.g. the installation of a European databank on central core disease including documentation of sporadic cases, magnetic resonance imaging of the muscle, further study of ryanodine receptor gene (RYR1) mutations and histological, immunohistochemical and electronmicroscopic studies.
A summary of the results of the workshop will be presented at the annual meeting of the European Malignant Hyperthermia Group, Paris, May 2001.

An extended report of this meeting is published inNeuromuscular Disorders, Volume 12, No.6, August 2002.

Dr. H. De Cauwer, (Antwerp, Belgium)
Prof. Dr. L. Heytens (Antwerp, Belgium)