Résumé :
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Desminopathies are familial or sporadic muscle disorders due to mutations in the desmin gene. The disease is autosomal dominant in most of the cases, but not infrequently results from de novo mutations. By contrast, recessive mutations have been described only in a few cases. Typically, the illness presents with lower and later upper limb muscle weakness slowly spreading to involve truncal, neck-flexor, facial, and bulbar muscles. The age of disease onset and rate of progression may vary depending on the type of inheritance and location of the causative mutation. Skeletal myopathy is often combined with cardiomyopathy manifested by conduction blocks, arrhythmias and chronic heart failure resulting in premature sudden death. Respiratory muscle weakness is a major complication in some patients. Muscle imaging studies show a characteristic pattern of muscle involvement with an early involvement of the semitendinosus, sartorious and gracilis at mid-thigh level, and peroneal group and anterior tibialis at the mid-leg. Sections of the affected skeletal and cardiac muscles typically show abnormal fiber areas containing protein aggregates consisting of desmin and many other proteins, and granulofilamentous material at electron microscopy level. More than forty desmin mutations are currently known. Most of them are located in the 2B alpha-helix of the desmin molecule. In our series of 30 patients with myofibrillar myopathy, 8 had a mutation in the desmin gene. We will summarize the clinical and myopathological characteristics of this series of patients illustrating the spectrum of manifestations associated with mutations in the desmin gene. Montse Olivé - Institut de Neuropatologia - IDIBELL-Hospital de Bellvitge - Feixa Llarga s/n 08907 Hospitalet de Llobregat, Barcelona, Spain - E-mail: 25169mop@comb.es
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