Inclusion-body myositis is the most frequent and disabling myopathy seen in patients over 50 years of age. The distinct clinical features that lead to correct diagnosis and inclusion-body myositis mimics are highlighted. Inclusionbody myositis has a complex pathogenesis in which autoimmune and inflammatory features coexist with elements of degeneration and abundant accumulations of various stre...

Inclusion body myositis is an insidious, slowly progressive myopathy of middle-aged and older individuals. Because of these characteristics, diagnosis is often delayed. Affected muscle is marked by the presence of rimmed vacuoles, inclusions, and an inflammatory infiltrate largely made up of CD8 T lymphocytes and macrophages. The inclusions contain beta-amyloid and phosphorylated tau protein, a...

The histochemical and ultrastructural study of muscle biopsies of two patients with a chronic muscle weakness and wasting showed particular changes in muscle fibers: (1) peripheral lined vacuoles, containing whorls of membranes and cytoplasmic debris; (2) collections of intranuclear and intrasarcoplasmic tubular filaments (16-18 nm in external diameter and 6.5 nm in inner diameter). These chang...

PURPOSE OF REVIEW To examine new developments in sporadic inclusion body myositis (IBM), including updated clinical and prognostic factors, novel autoantibody associations, unique histopathologic findings, proposed new clinical diagnostic criteria, and novel therapeutic agents. RECENT FINDINGS IBM is a slowly progressive disease, leading to wheelchair use, on average, 12-20 years after onset ...

PURPOSE OF REVIEW Inclusion body myositis (IBM) is an enigmatic progressive disease of skeletal muscle. This review provides a summary of the clinical and pathophysiologic aspects of IBM. RECENT FINDINGS The development of diagnostic blood testing for IBM followed from the discovery of a B-cell pathway in IBM muscle and circulating autoantibodies against NT5C1A, further establishing IBM's sta...

Sporadic inclusion body myositis (IBM) is a muscle disease with two separate pathogenic components, degeneration and inflammation. Typically, nonnecrotic myofibers are focally surrounded and invaded by CD8(+) T cells and macrophages. Both attacked and nonattacked myofibers express high levels of human leukocyte antigen class I (HLA-I) molecules, a prerequisite for antigen presentation to CD8(+)...

Inclusion body myositis is a form of inflammatory myopathy. We identified 4 cases of inclusion body myositis showing granuloma formation in muscle tissue and aimed to assess the features of this atypical form of inclusion body myositis. We retrospectively reviewed consecutive patients who satisfied European Neuromuscular Centre IBM Research Diagnostic Criteria 2011. Then, we assessed clinical p...

The idiopathic inflammatory myopathies (IIMs) are a heterogeneous group of rare disorders that share many similarities. In addition to sporadic inclusion body myositis (IBM), these include dermatomyositis, polymyositis, and autoimmune necrotizing myopathy. IBM is the most common IIM after age 50 years. Muscle histopathology shows endomysial inflammatory exudates surrounding and invading nonnecr...