[Inflammatory myopathies, autoimmune necrotizing myopathies and adult-onset genetic myopathies: differential diagnosis]

Abstract

The inflammatory myopathies are an important and treatable group of disorders. The diagnostic criteria and the classifications are complex and subject to debate. Furthermore, there is clinical and histopathological overlap between the features of inflammatory myopathies and those of adult-onset genetic myopathies. In this review, we will discuss the two more common pitfalls in inflammatory myopathies diagnosis: firstly, the misdiagnosis between different types of inflammatory myopathies and uncommon myopathies; secondly, the confusion between inflammatory myopathies and genetic myopathies. Among the group of limb-girdle dystrophies, dysferlinopathies are the more common confounding myopathies. An accurate diagnosis is essential for an optimal management in patients with myopathies.