Myositis - Idiopathic inflammatory myopathies (IIM)

Myositis also called Idiopathic inflammatory myopathies (IIM), commonly referred to as “myositis,” are chronic diseases marked by muscle inflammation.

Summary points:

Can Covid bring on myositis?

SARS-CoV-2 mediates infection using the ACE-2 receptor as a host, suggesting that covid-19 can directly infect skeletal muscle causing the inflammatory response seen in myopathies such as covid-19-induced myositis. Thus, muscle weakness and myalgia are commonly reported symptoms of covid-19.

What are the three stages of myositis?

The process of myositis ossificans can be divided into three stages: early, intermediate, and mature. The early phase occurs in the first four weeks of injury with inflammatory phase of bone formation.

What is the age of onset for myositis?

Only about 5 new myositis cases per 1 million population in the United States are diagnosed every year. For PM and DM, the most common ages of onset cluster around two age groups: between 10 and 15 years of age and between 45 and 60 years of age.

What age is myositis most common?

Inclusion body myositis usually affects people over age 50. It may go undiagnosed for a long time before the symptoms of muscle weakness manifests. Juvenile myositis affects children between ages 5 and 15. It often causes a rash as well as fatigue and muscle weakness.

What is the final stage of myositis?

Sporadic inclusion body myositis is a chronic progressive disorder, leading to major disabilities at the end stage of the disease due to extensive muscle weakness.

What can be mistaken for myositis?

Myositis mimics: Clues for making the right diagnosis
    Myotonic dystrophies. These are more often type 2 than type 1. …
    Limb girdle muscular dystrophy type 2 B (dysferlinopathy). In the legs, this often affects the astrocnemius muscle, and this will be visible on MRI. ...
    Facioscapulohumeral muscular dystrophy (FSHD).

Where does myositis hurt?

Symptoms of Myositis:
Dermatomyositis, polymyositis, and other inflammatory myositis conditions tend to cause weakness that gets worse slowly over weeks or months. The weakness affects large muscle groups, including the neck, shoulders, hips, and back. Muscles on both sides are usually affected.

What are the first signs of myositis?

Symptoms:
    Difficulty standing up from a seated position.
    Difficulty climbing stairs.
    Difficulty lifting the arms.
    Fatigue after standing or walking a long time.
    Trouble swallowing or breathing.
    Muscle pain that does not subside within a few weeks.
    A red or purple colored rash on the eyelids, elbows, knees and knuckles.

Which muscle is most susceptible to myositis?

Usually, myositis ossificans develops after a traumatic injury. Most often, it affects large muscles, such as in your arms or legs.

Can stress cause myositis?

For those of us with chronic autoimmune diseases, such as the idiopathic inflammatory myopathies, generally referred to as myositis, stress can be even more damaging. It has been shown that stress can diminish our immune system, cause disease, and increase inflammation.

Does myositis affect the brain?

Myositis can cause “brain fog” and even memory loss, making concentration, organization, and other related tasks difficult. Myositis causes a variety of symptoms and affects each person differently.

Does myositis show up in blood work?

Blood Test:
Elevated levels may mean you have an inflammatory myopathy. Creatine kinase levels are usually very high in people with polymyositis and dermatomyositis but only slightly elevated or even normal in people with inclusion body myositis.

What vitamin is deficient in myositis?
Conclusions: Low serum levels of vitamin D were found in most patients with IIM and may confer a risk factor for developing adult myositis, similar to some other autoimmune diseases.

Common Pathways of Autoimmune Inflammatory Myopathies and Genetic Neuromuscular Disorders https://link.springer.com/article/10.1007/s12016-011-8286-7