This refers to the muscle inflammation that can develop from a number of causes such as certain medicines, chronic disease or from exercise. In most cases, this can develop because of an underlying condition when the immune system accidentally attacks the healthy tissue of the body. The symptoms of myositis include tripping or falling, fatigue after walking and trouble swallowing or breathing. The muscle weakness can progressively deteriorate without treatment which could vary from week to week or month to month. There are various types of myositis; polymyositis, dermatomyositis, inclusion-body myositis and juvenile forms of myositis.
Polymyositis
This is an uncommon condition that can cause muscle weakness on both the sides of the body making it difficult to carry on regular tasks such as climbing stairs or lift objects. This condition commonly affects individuals in their 30s, 40s and 50s with the symptoms progressively developing over weeks or months. The muscle weakness affects the muscles closest to the trunk such as those of the shoulders, upper arms, neck and the hips. Some of the individuals can experience breathing problems and difficulty swallowing. There is no cure for polymyositis but the treatment can help improve the muscle strength and their functions.
Dermatomyositis
This is also an uncommon condition that mostly affects individuals from the age of late 40s to early 60s. It can also affect children between the ages of 5 and 15. The symptoms of this are similar to polymyositis but include the distinctive rash. Before the onset of the muscle symptoms, the red or purple-colored rash can appear in places such as the eyelids, cheeks, nose, elbows, upper chest and the knees. The rash can be painful or itchy with the presence of hard lumps called calcinosis.
Inclusion body myositis
This is characterized by the progressive muscle weakness and wasting that develops after the age of 50 although some of the individuals can present the symptoms as early as their 30s. This condition appears to be more common among men than women and a small number of cases have been identified to be hereditary although most of them are sporadic. The symptoms can appear slowly over months or years which can include muscle weakness on the thighs, wrists and fingers. The affected cases may frequently fall, present difficulty swallowing, weakened hand grip and trouble with climbing stairs.
Juvenile forms of myositis
This develops among children under the age of 18. The juvenile dermatomyositis is characterized by the muscle weakness and skin rash. The juvenile polymyositis is an extremely rare condition. Children with juvenile myositis can present muscle weakness most often appearing in the areas closest to the body such as the neck, stomach, legs and upper arms. They can also present reddish-purple rash, fatigue, irritability, complaints of tummy pain, problem climbing stairs, difficulty lifting their head, trouble swallowing and hoarse voice.
Treatment
There is no cure for the disease but the treatment can provide relief from the symptoms. The treatment can include physiotherapy and exercise so the joints don’t become stiff and to ensure their movement. The treatment can also include medications to control symptoms, physical therapy to maintain or improve the strength or the administration of intravenous immunoglobulin in the severe cases.
References
http://www.mayoclinic.org/diseases-conditions/polymyositis/basics/treatment/con-20020710
http://www.mayoclinic.org/diseases-conditions/dermatomyositis/basics/definition/con-20020727
https://www.hopkinsmyositis.org/myositis/inclusion-body-myositis/
