Inclusion body myositis pathogenesis: Steady progress

What is in the Myopathy Literature?

This review is focused on recent reports of sporadic inclusion body myositis (sIBM), myopathy in patients with human immunodeficiency virus type 1 (HIV) infection, and necrotizing autoimmune myopathy with antibodies to signal recognition particle. The sIBM articles cover associations with certain genetic polymorphisms, the possible pathogenic role of anti-cytosolic 5'-nucleotidase 1A antibody, and disease-related burden and health care costs. Another article addressed the possible pathogenic role of signal recognition particle antibody in necrotizing myopathy. A series of HIV patients with overlapping features of sIBM and polymyositis are highlighted as is a report of a patient with HIV and late-onset rod-body myopathy that may have improved with immunotherapy.

Advances in the early diagnosis and therapy of inclusion body myositis

PURPOSE OF REVIEW

To describe recent advancements in diagnostic and therapeutic approaches to inclusion body myositis (IBM).

RECENT FINDINGS

Our understanding of the implications of anti-cytosolic 5'-nucleotidase 1A autoantibody status in IBM and other diseases is increasing. Muscle imaging using magnetic resonance techniques and ultrasound is increasingly being performed and characteristic patterns of muscle involvement may help with diagnosis. Longitudinal imaging studies are likely to help with monitoring and as an outcome measure in clinical trials. Recent small-scale studies of Arimoclomol and Rapamycin have shown promising results and further investigation of these medications is ongoing. Exercise is likely to form an increasingly important facet of management of patients with IBM, but the optimal type of exercise programme to enrol patients in is not yet determined.

SUMMARY

Antibody testing and muscle imaging results may improve our ability to diagnose IBM and the availability of effective disease modifying treatments targeting novel non-inflammatory pathways could soon become a reality. It remains the duty of those involved in the management of patients with IBM to facilitate involvement in clinical trials and other research studies.