Disorders of the NMJ present more of a challenge. NMJ disorders may present with proximal muscle weakness similar to myopathies. Postsynaptic disorders (e.g., MG) typically have normal CMAP amplitudes at rest. [clinicalgate.com]

Depending on the underlying defect, some patients may present in infancy or early childhood, whereas others may not present until well into adulthood. [the-rheumatologist.org]

Atrophy of muscles, when present, is proportionate to the weakness. The deep tendon reflexes diminish and disappear with the progression of weakness. About 30% of patients present with respiratory failure. [emedicine.medscape.com]

Very long chain acyl-co enzyme A deficiency presents clinicopathologically similar to CPT II deficiency. [annalsofian.org]

• Chest Deformity

  Musculoskeletal problems include joint contractures, chest deformities and spinal deformities, including scoliosis. Malignant hyperthermia can occur with central core disease. Prognosis This depends on the specific diagnosis. [patient.info]

However, a key diagnostic feature is the absence of a rise in serum venous lactate during the Forearm ischemic exercise test in Workup. Also, the cramp, when recorded by needle EMG, is silent (contracture). [emedicine.medscape.com]

Because these symptoms may be nonspecific and lack any clear temporal or anatomic pattern, their workup may entail costly and uninformative tests. [the-rheumatologist.org]

In general, treatment options for men and women are the same. [merckmanuals.com]

[…] of screening and treatment for dyslipidemia. [uspreventiveservicestaskforce.org]

Activation of PPARs, by treatment with fibrates rescued the phenotype and reduced mortality rates in these mice. These findings may have a major impact for patients with NLSDM if these results can be translated to humans. [clinicaltrials.gov]

In Gaucher disease, the effect of treatment on pulmonary disease depends on the case series and the type of Gaucher disease. [err.ersjournals.com]

In acquired myopathies, treatment is targeted toward the underlying cause. Treatment of statin myopathies is dependent on creatine phosphokinase levels and degree of muscle symptoms. Consider lower doses when initiating statin therapy. [clevelandclinicmeded.com]

Prognosis This depends on the specific diagnosis. The primary disorders are incurable conditions with varied prognosis. Secondary myopathy may be corrected by treating the underlying cause. [patient.info]

Prognosis: Most patients can pursue normal daily activities and do not develop progressive problems. Precautions regarding diet and exercise are an important component of a successful outcome. BIBLIOGRAPHY Martin A, Haller RG, Barohn R. [rheumaknowledgy.com]

Despite this, the age at onset of respiratory symptoms seems critical for the definition of lung disease severity, and patients with symptoms and signs in the first decade of life generally have worse pulmonary prognosis [ 72 ]. [err.ersjournals.com]

In cases suspected to be a primary inflammatory myopathy, specific autoantibodies can be considered to determine the prognosis and rule out associated conditions. [clevelandclinicmeded.com]

Rhabdomyolysis may also be seen with infectious etiologies, alcohol, and toxic exposures. [clevelandclinicmeded.com]

Not all muscle cramps, however, are related to metabolic muscle diseases and can be due to benign etiologies. When benign entities are ruled out and metabolic myopathy is suspected, the first diagnostic step is to perform an electromyogram. [bcm.edu]

Hyperparathyroidism Adrenal (Addisons or Cushings) disease Infection HIV Toxoplasmosis Trichinosis Cysticercosis Drug-Induced Alcohol Statins, fibrates Hydroxychloroquine Cyclosporin A Amiodarone Others Metabolic myopathies Periodic paralysis Hypokalemia Etiology [rheumaknowledgy.com]

Metabolic myopathies are the most clearly defined and etiologically understood muscle disorders because their fundamental biochemical defects are known through recent developments in molecular biology and biochemistry. [emedicine.medscape.com]

Epidemiology These are all relatively uncommon diseases: Duchenne muscular dystrophy is easily the most common childhood-onset muscular dystrophy and affects 1 in 3,300 boys. [ 6 ] The prevalence of Duchenne muscular dystrophy is 63 cases per million. [patient.info]

A genetic epidemiologic study of the carnitine transporter gene OCTN2 from Japan estimates the incidence of primary systemic carnitine deficiency as one in 40,000 births. [annalsofian.org]

Table 1 Clinical Features of Common Myopathies Myopathy Epidemiology Distribution of Weakness Other Systemic Manifestations Acquired Myopathies Dermatomyositis Female > male Peak incidence: children and ages 40–60 yr Symmetrical proximal muscle weakness [clevelandclinicmeded.com]

It appears that the general spectrum of myopathies described in the world literature is also seen in India, although the prevalence is difficult to ascertain, as there is very little published epidemiological data. [annalsofneurosciences.org]

The pathophysiological principles of metabolic myopathies may be simplified into a logical biochemical cascade. [emedicine.medscape.com]

Back to Top Pathophysiology Disruption of the structural integrity and metabolic processes of muscle cells can result from genetic abnormalities, toxins, inflammation, infection, and hormonal and electrolyte imbalances. [clevelandclinicmeded.com]

There is limited evidence about primary prevention of coronary heart disease using drugs in older populations; however, several secondary prevention trials that included individuals aged 65 and older showed a reduction in coronary heart disease events [uspreventiveservicestaskforce.org]

Rehabilitation specialists can help determine appropriate exercise and stretching regimens to prevent muscle loss and maximize activity. [kennedykrieger.org]

Prevention Genetic counselling is, in some of the most common myopathies such as Duchenne muscular dystrophy, the only intervention that can prevent disease. In general: Give genetic counselling early. [patient.info]

Treatment is indicated for all patients with ASCVD (secondary prevention) and for some without (primary prevention). [merckmanuals.com]

Statin therapy for primary prevention of cardiovascular disease. JAMA. 2013 ; 310:2451–2452. [jaha.ahajournals.org]