What is post-infectious reactive myositis?
After some viral infections the body’s immune system, after killing the virus, may cause inflammation in parts of the body for a few months. If this occurs in muscle, the result is a short-lived myositis that is called ‘post-infectious reactive’. People with this condition develop widespread muscle pain and may get muscle weakness. Some of the tests for polymyositis may show positive, but the condition is usually mild and always settles without the need for specific treatment. Are there any other types of myositis? There is a disease called inclusion body myositis (IBM) which is similar to polymyositis and dermatomyositis. People with IBM have the symptoms of muscle weakness, a raised level of the enzyme creatine phosphokinase, and similar muscle biopsy results. It is, however, different in that the weakness most often affects muscles near the ends of the limbs (such as those of the hands, forearms and calves) and symptoms of muscle pain occur only rarely. Although most of the features
