[Current diagnosis in muscular dystrophies. New developments, methods of examination and case examples]

Recent progress in the field of molecular genetics revealed a broader spectrum of dystrophin-related disorders than previously assumed. In addition, the pathogenetic basis of other types of muscular dystrophies could be identified: some autosomal-recessive limb girdle dystrophies are caused by mutations of sarcoglycan genes, others are caused by deficiency of the sarcoplasmatic enzyme calpain-3. Emery-Dreifuss muscular dystrophy is due to the deficiency of the nuclear membrane protein emerin. About 50% of congenital muscular dystrophies are related to mutations of a extracellular matrix protein merosin (alpha-laminin). A series of monoclonal antibodies for immunohistochemistry is now available recognizing many cytoskeletal muscle proteins. In combination with molecular genetics a diagnostic flow chart can be developed which allows a definite diagnosis in most cases. In this review disease entities are illustrated by case reports. We discuss the significance of immunohistochemical and molecular methods for diagnosis.