Assessment of PABPN1 nuclear inclusions on a large cohort of patients and in a human xenograft model of oculopharyngeal muscular dystrophy.

Oculopharyngeal muscular dystrophy (OPMD) is a rare muscle disease characterized by an onset of weakness in the pharyngeal and eyelid muscles. The disease is caused by the extension of a polyalanine tract in the Poly(A) Binding Protein Nuclear 1 (PABPN1) protein leading to the formation of intranuclear inclusions or aggregates in the muscle of OPMD patients. Despite numerous studies stressing the deleterious role of nuclear inclusions in cellular and animal OPMD models, their exact contribution to human disease is still unclear.

Myositis with prominent B-cell aggregates causing shrinking lung syndrome in systemic lupus erythematosus: a case report.

Background: Shrinking lung syndrome (SLS) is a rare manifestation of systemic lupus erythematosus (SLE) characterized by decreased lung volumes and diaphragmatic weakness in a dyspneic patient. Chest wall dysfunction secondary to pleuritis is the most commonly proposed cause. In this case report, we highlight a new potential mechanism of SLS in SLE, namely diaphragmatic weakness associated with myositis with CD20 positive B-cell aggregates.

A National Spinal Muscular Atrophy Registry for Real-World Evidence.

Background: Spinal muscular atrophy (SMA) is a devastating rare disease that affects individuals regardless of ethnicity, gender, and age. The first-approved disease-modifying therapy for SMA, nusinursen, was approved by Health Canada, as well as by American and European regulatory agencies following positive clinical trial outcomes. The trials were conducted in a narrow pediatric population defined by age, severity, and genotype.

Statin-induced anti-HMGCR myopathy: successful therapeutic strategies for corticosteroid-free remission in 55 patients.

Objective: To describe successful therapeutic strategies in statin-induced anti-HMGCR myopathy.

Methods: Retrospective data from a cohort of 55 patients with statin-induced anti-HMGCR myopathy, sequentially stratified by the presence of proximal weakness, early remission, and corticosteroid and IVIG use at treatment induction, were analyzed for optimal successful induction and maintenance of remission strategies.

Results: A total of 14 patients achieved remission with a corticosteroid-free induction strategy (25%).

Lower motor neuron syndrome due to cauda equina hypertrophy with onion bulbs.

Introduction: Hypertrophy of the nerve roots of the cauda equina may occur with both acquired and inherited neuropathies. Although selective nerve root involvement of the sensory roots has been described and termed chronic inflammatory sensory polyradiculoneuropathy (CISP), selective involvement of the proximal motor roots has not been described.

Methods: Clinical, electrophysiological, MRI, and pathological findings are reported.

Demyelinating symmetric motor polyneuropathy with high titers of anti-GM1 antibodies.

High titers of anti-GM1 ganglioside antibodies have been associated with multifocal motor neuropathy, a chronic asymmetric and exclusively motor disorder. We describe a patient with a progressive selective motor but symmetric polyneuropathy, followed over 5 years, with markedly elevated titers of anti-GM1 antibodies. The electrophysiological changes suggestive of motor demyelination were widespread, beyond conduction block alone, and involved contiguous nerve segments with complete sparing of sensory conduction.

The role of muscle biopsy in the age of genetic testing.

Purpose Of Review: The purpose of this review is to discuss the role of muscle biopsy in the current age of genetic testing.

Recent Findings: The diagnostic approach to patients with suspected genetically determined myopathies has been altered by recent advances in molecular diagnostic technologies and by the increased number of conditions for which the genetic alterations have been identified. Myopathological aspects can narrow down the differential diagnosis when the clinical phenotype is not informative enough and can help guide the molecular investigation.

Sporadic inclusion body myositis: pathogenic considerations.

Sporadic inclusion body myositis is the commonest acquired disease of skeletal muscles after 50 years of age, and as such it has commanded a great deal of attention of investigators over the past 25 years. As a result, a large amount of information has accumulated concerning its clinical profile, myopathology, and immunopathology. In the myopathology and immunopathology, there is general agreement that the characteristic features could be divided into a degenerative and an inflammatory group.