Myositis with prominent B cell aggregates may meet classification criteria for sporadic inclusion body myositis.

The objective of this study was to report the clinical, serological and pathological features of patients with autoimmune myositis other than dermatomyositis, who displayed both muscle weakness on physical examination and prominent B cell aggregates on muscle pathology, defined as ≥ 30 CD20+ cells/aggregate. Specifically, the presence of a brachio-cervical inflammatory myopathies or a sporadic inclusion body myositis (sIBM) phenotype was recorded. Over a three-year period, eight patients were identified from two university neuropathology referral centers.

Molecular diagnosis of muscular diseases in outpatient clinics: A Canadian perspective.

Objective: To evaluate the diagnostic yield of an 89-gene panel in a large cohort of patients with suspected muscle disorders and to compare the diagnostic yield of gene panel and exome sequencing approaches.

Methods: We tested 1,236 patients from outpatient clinics across Canada using a gene panel and performed exome sequencing for 46 other patients with sequential analysis of 89 genes followed by all mendelian genes. Sequencing and analysis were performed in patients with muscle weakness or symptoms suggestive of a muscle disorder and showing at least 1 supporting clinical laboratory.

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%).

Diagnosis of late-onset Pompe disease and other muscle disorders by next-generation sequencing.

Background: Late-onset Pompe disease (LOPD) is a rare treatable lysosomal storage disorder characterized by progressive lysosomal glycogen accumulation and muscle weakness, with often a limb-girdle pattern. Despite published guidelines, testing for LOPD is often overlooked or delayed in adults, owing to its low frequency compared to other muscle disorders with similar muscle patterns. Next-generation sequencing has the capability to test concurrently for several muscle disorders.

Eosinophilic granulomatosis with polyangiitis (Churg-Strauss syndrome) presenting as diffuse myositis.

Background: Eosinophilic granulomatosis with polyangiitis is a complex multisystemic syndrome with heterogeneous presentation. Most often, there is a clinical history of asthma or other atopic conditions, and current presentation generally includes signs of cutaneous or pulmonary involvement. Very few reports described myalgia or weakness as the chief complaint.

Distal muscle involvement in granulomatous myositis can mimic inclusion body myositis.

The authors report on four patients aged over 50 with chronic myopathy suggestive of sporadic inclusion body myositis. They present progressive and selective weakness of the quadriceps femoris muscles. Asymmetrical and selective atrophy of the forearm muscles were noted in all, with more severe involvement of the flexors than the extensors.

[Dysimmune neuropathies: current diagnosis and therapy].

Dysimmune neuropathies encompass an acute form, Guillain-Barré syndrome (GBS), and mainly 3 chronic forms: chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), multifocal motor neuropathy, and polyneuropathy associated with anti-MAG (myelin-associated-glycoprotein) IgM monoclonal gammopathy. Recent concepts have concerned both incidence and mortality rates, and better scoring system for predict outcome in GBS, but new therapeutical strategy is needed for the so-called "benign" forms and for relapsing forms after first-line IVIg therapy. In chronic forms, criteria for diagnosis and guidelines for management have been edited in the recent years, together with recommendations for outcome measures.

A case of familial Creutzfeldt-Jakob disease presenting with dry cough.

Background: Clinical diagnosis of Creutzfeldt-Jakob disease (CJD) is based on the classical triad of rapidly progressive dementia, myoclonus and abnormal EEG. The 200k mutation within the gene encoding PrP, located on the short arm of chromosome 20, accounts for more than 70% of families with CJD worldwide.

Case Report: Herein, we report a patient who developed persistent dry cough and classical signs of CJD, including severe cognitive decline, cerebellar signs, and myoclonic jerks, leading to death a few weeks after disease onset.