Case Presentation: A 90 year old woman presented with weakness for one month. Atorvastatin 80mg was newly prescribed for a myocardial infarction. On exam proximal muscle strength on all extremities was 3/5. [shmabstracts.com]

An inflammatory exudate was present in perivascular regions in perimysium especially where the necrotic fibers were present. Myositis specific antibodies including Jo-1, Mi-2, PL-7, PL-12, SRP, EJ and OJ were negative. [bmcearnosethroatdisord.biomedcentral.com]

Abstract A 73-year-old male presented with jaundice and severe muscle weakness. He was diagnosed with distal cholangiocarcinoma and paraneoplastic necrotizing autoimmune myopathy (NAM). [karger.com]

All patients presented with painless proximal weakness of varying severity. Investigations. Investigation findings demonstrated elevated CK in all patients. These results ranged from 2,700 to 16,200 IU/L at presentation. [nn.neurology.org]

The case presented is that of a 51-year-old female patient who developed progressive, proximal muscle weakness with bulbar involvement after treatment with statin. [neurologyindia.com]

• Weakness

  Neurological exam revealed symmetrical bilateral proximal shoulder girdle and thigh weakness. [lipid.org]

  Complete resolution of weakness may be difficult to achieve. Conclusions: When discontinuation of statin therapy does not lead to resolution of weakness or elevated CPK, hospitalists should consider IMNM. [shmabstracts.com]

  Despite cessation of the statin, her weakness progressed such that her mobility was impaired within 2 months of onset, with examination demonstrating shoulder abduction and adduction weakness and hip flexion and extension weakness (graded 3/5). [nn.neurology.org]

  Bulbar and limb weakness improved gradually and she went home walking with support. [neurologyindia.com]

  RESULTS: Lower extremity weakness predominated (46 [73%]). Distal weakness (26 [41%]), dysphagia (22 [35%]), and dyspnea (23 [37%]) were common. [ncbi.nlm.nih.gov]

• Progressive Dysphagia

  Progressive dysphagia is associated with a poorer prognosis and a poorer quality of life. [patient.info]

• Myopathy

  In the list of rare diseases of Orphanet [12], immune-mediated necrotizing myopathy appears at n. 206569 and has several synonyms: anti-HMG-CoA myopathy, anti-SRP myopathy, autoimmune necrotizing myositis, IMNM, immune myopathy with myocyte necrosis, [journals.seedmedicalpublishers.com]

  The 3 most common inflammatory myopathies are polymyositis (PM), dermatomyositis (DM), and inclusion body myositis. This review details the clinical findings noted in PM, DM, and the emerging entity of autoimmune necrotizing myopathy. [ncbi.nlm.nih.gov]

  Necrotizing myopathy (also called necrotizing autoimmune myopathy [ NAM ] or immune-mediated necrotizing myopathy [ IMNM ]) is a newly defined form of idiopathic inflammatory myopathy. [myositis.org]

  Metabolic and mitochondrial myopathies; Sporadic inclusion body myositis; Toxic myopathies; Idiopathic Inflammatory myopathies; Approach to muscle disease. [books.google.de]

• Muscle Weakness

  Our patient showed fast progression of muscle weakness preoperatively. [karger.com]

  In the past, all patients who presented with muscle weakness, elevated creatine kinase levels, and other symptoms of myopathy, but who didn’t have skin involvement, were classified as having polymyositis. [myositis.org]

  It typically presents with distal upper extremity weakness accompanied by proximal lower extremity muscle weakness. [patient.info]

  HMGCR IMNM is associated with dysphagia in up to 35 % of patients, symmetric proximal muscle weakness in 95 %, distal muscle weakness in 41 %, and dyspnea in 37 %. CKs over 6000 and significant necrosis on muscle biopsy are commonly seen [ 6 – 8 ]. [bmcearnosethroatdisord.biomedcentral.com]

  Diagnosis: Clinical features plus positive antibodies and usually with necrotizing myopathy on biopsy Clinical features: Age range 30-60, progressive myopathy with profound proximal muscle weakness. [learningneurology.com]

• Proximal Muscle Weakness

  Diagnosis: Clinical features plus positive antibodies and usually with necrotizing myopathy on biopsy Clinical features: Age range 30-60, progressive myopathy with profound proximal muscle weakness. [learningneurology.com]

  The combined incidence of polymyositis and dermatomyositis is 4 to 10 cases per million population per year. 2 The idiopathic inflammatory myopathies share common features, including proximal muscle weakness, elevated muscle enzymes (creatinine phosphokinase [clinicaladvisor.com]

  The case presented is that of a 51-year-old female patient who developed progressive, proximal muscle weakness with bulbar involvement after treatment with statin. [neurologyindia.com]

  Case Presentation: A 90 year old woman presented with weakness for one month. Atorvastatin 80mg was newly prescribed for a myocardial infarction. On exam proximal muscle strength on all extremities was 3/5. [shmabstracts.com]

  […] of proximal muscle weakness, with neck flexor rather than extensor weakness, associated with an elevated serum CK level, and no ocular weakness. 4 NAM can also be associated with dysphagia, dyspnoea and myalgia, 1,3,5,9 and there have been reports of [acnr.co.uk]

• Muscular Atrophy

  He is currently involved in multiple clinical trials of novel genetic interventions for the treatment of spinal muscular atrophy and Duchenne muscular dystrophy. Dr. H. [books.google.de]

  Rimmed vacuoles with b-amyloid and ubiquitinated filamentous deposits in the muscles of patients with long-standing denervation (post-poliomyelitis muscular atrophy): similarities with inclusion body myositis Hum Pathol 1998 ; 29 : 1128-1133 [cross-ref [em-consulte.com]

• Polyneuropathy

  […] clinical entities is then discussed in detail, the coverage including, for example, myasthenia gravis, polymyositis, immune-mediated neuropathies, multifocal motor neuropathies, amyotrophic lateral sclerosis, paraneoplastic neuropathies, and diabetic polyneuropathy [books.google.de]

  Semin Neurol 24:155–163 PubMed CrossRef Google Scholar Dalakas MC (2013) Pathophysiology of autoimmune polyneuropathies. [link.springer.com]

  Sensory or autonomic changes only tend to occur if there is also a concurrent polyneuropathy, such as may occur with diabetes. [patient.info]

• Paresis

  J Rheumatol 40:550–564 PubMed CrossRef Google Scholar Lefaucheur J, Nordine T, Rodriguez P, Brochard L (2006) Origin of ICU acquired paresis determined by direct muscle stimulation. [link.springer.com]

• Asthenia

  Practical Applications Patients taking high dose statins, over the age of 50, who develop myopathy with muscular asthenia associated with increased CPK > 5 times the upper limit are at risk of developing autoimmune necrotizing myopathy In subjects taking [journals.seedmedicalpublishers.com]

• Lymphocytic Infiltrate

  Some macrophage infiltration can occur but typically no lymphocytic infiltration. [learningneurology.com]

  Of note, ∼20% of anti-SRP and anti-HMGCR positive patients have significant lymphocytic infiltrates on muscle biopsy and thus would not be formally categorized as having IMNM; aside from this, these patients are clinically indistinguishable from other [journals.lww.com]

  Macrophage infiltration was noted, with a relative paucity of lymphocytic infiltration. Major histocompatibility complex (MHC) class I expression was not upregulated at the time of this biopsy. [nn.neurology.org]

  Muscle biopsy did not reveal interstitial lymphocytic infiltration to suggest polymyositis. She was diagnosed to be having statin-triggered immune-mediated necrotizing myopathy. [neurologyindia.com]

  Clonal restriction of T-cell receptor expression by infiltrating lymphocytes in inclusion body myositis persists over time. [em-consulte.com]

Medical treatment is mostly based on more frequently arising IIMs. Prednisone treatment is the first choice on an empiric basis [ 16 ]. [karger.com]

Some IMNM patients respond very well to treatment, while others may not. Finding the right treatment, or a combination of treatments can take months-to-years. Long-term steroid use may be a major source of morbidity. [understandingmyositis.org]

Muscle Nerve Myopathywithantibodiestothesignalrecognition particle: clinicalandpathological features AlfughamNB,Mahler M,MiloneM(2015)Clinical features and treatment outcomes of Necrotizing AutoimmuneMyopathy Clinical features and treatment outcomes of [semanticscholar.org]

This book provides state of the art information on the pathogenesis, diagnosis, and treatment of a range of inflammatory, autoimmune, and idiopathic neuromuscular disorders. [books.google.de]

SUMMARY: It is important to recognize and distinguish NAM from other causes of myocyte necrosis, because it has the potential of being amenable to treatment. [ncbi.nlm.nih.gov]

Progressive dysphagia is associated with a poorer prognosis and a poorer quality of life. [patient.info]

Scientists continue to learn more about how these autoantibodies shape pathophysiology, diagnosis, disease monitoring, prognosis and optimum treatment. [the-rheumatologist.org]

Correct subtype identification and the distinction of these conditions from other diseases that have similar characteristics are fundamental in differing prognosis and differing responses to therapy. [pathologicallyspeaking.blogspot.com]

IMNM Prognosis The prognosis of Immune-Mediated Necrotizing Myopathy depends on many varying factors including patient response to treatment, the severity of disease and its manifestations, the presence of pulmonary or cardiac involvement, and associated [understandingmyositis.org]

The Message Aside from the distinctive biopsy and antibody findings with immune-mediated necrotizing myopathy, the prognosis also differs from that of the more typical statin-associated myopathy. [medpagetoday.com]

A muscle biopsy was performed and revealed a necrotizing myopathy with high probability of autoimmune etiology. [scopemed.org]

Clues to these other etiologies are often apparent in the history. [clinicaladvisor.com]

Data are limited concerning differences among etiologic subgroups and treatment outcomes in NAM. [ncbi.nlm.nih.gov]

Etiology The disease is thought to be related to an immune response possibly triggered by drug therapy (statins), connective tissue diseases, or cancer. [orpha.net]

100,000 ( Ann Rheum Dis 2009;68:1192 ), but only 3.8 per 100,000 in US ( Muscle Nerve 2012;45:676 ) Peak incidence is in older patients, with a mean age of 56 years and a male to female ratio of 1.6 : 1 Extremely rare in younger patients and childhood Etiology [pathologyoutlines.com]

Summary Epidemiology The prevalence and annual incidence of NAM are not known but the disorder is very rare. About 300 cases have been reported to date. Clinical description Age of onset ranges from 30 to 70 years of age in reported cases. [orpha.net]

Skeletal muscle shows myopathic changes with evidence of myofiber degeneration and regeneration with lymphocytes invading non necrotic myofibers Predominant inflammatory cell is the CD8+ T lymphocyte Terminology Polymyositis or idiopathic polymyositis Epidemiology [pathologyoutlines.com]

Interest has been stimulated by the finding that substances deposited in muscle are similar to those found in the brain in Alzheimer's disease - eg, amyloid precursor proteins. [ 7, 8 ] Epidemiology [ 1 ] Most cases present in patients aged over 50 years [patient.info]

The present article summarizes the main features of statin-related IMNM, describing diagnosis, classification, epidemiology, treatment, and the main autoantibodies detected. [journals.seedmedicalpublishers.com]

Epidemiology of adult idiopathic inflammatory myopathies in a U.S. Managed care plan. Muscle Nerve 2012; 45 (5):676-83. [ Links ] 4. Needham M, Corbett A, Day T, Christiansen F, Fabian V, Mastaglia F. [scielo.cl]

Clinical features, pathophysiology, and treatment of polymyositis and dermatomyositis; inclusion body myositis; metabolic myopathies; drug-induced myopathies; muscular dystrophies and neurologic diseases; laboratory testing and imaging; electrophysiological [books.google.de]

Scientists continue to learn more about how these autoantibodies shape pathophysiology, diagnosis, disease monitoring, prognosis and optimum treatment. [the-rheumatologist.org]

In most subjects with statin-associated musculoskeletal side effects, discontinuing the offending medication will halt the pathophysiologic process, and the subsequent regeneration of myofibers will restore muscle function. [neurologyindia.com]

MD, FAAN National University of Athens Medical School, Department of Pathophysiology,75, Mikras Asias street, 11527 Athens, Greece. [em-consulte.com]

Statin-associated autoimmune myopathies: A pathophysiologic spectrum. Can J Neurol Sci 2014; 41: 638-47; https://doi.org/10.1017/cjn.2014.22 20. Musset L, Allenbach Y, Benveniste O, et al. [journals.seedmedicalpublishers.com]

Proper recognition of this ominous complication is important to prevent further damage from statin use. [mdedge.com]

Discussion Statins are among the most prescribed medications in the world because of the excellent evidence demonstrating efficacy in primary and secondary prevention of cardiovascular events. [lipid.org]

Some treat newly diagnosed patients with immunosuppression on the basis that early suppression of the inflammatory cascade may prevent downstream effects leading to muscle degeneration. [patient.info]

We want to prevent this autoimmune disease.” Although statins are tolerated by most patients, about 5 percent who take them experience muscle pain and/or weakness severe enough to warrant stopping the medication. [hopkinsmedicine.org]

From the American Heart Association: 2013 ACC/AHA Guideline on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults Clinical Practice Guidelines for Prevention Vencovsky and colleagues reported no financial disclosures [medpagetoday.com]