Myositis secondary to bacterial infection is common and is often associated with trauma or infection of the skin, fascia, or other adjacent organs. It is particularly frequent in immunocompromised patients in whom recovery tends to be delayed. Common bacteria causing myositis include Staphylococcus aureus, group A Streptococcus, and Escherichia coli. Although infection can usually be controlled with proper treatment, acute rhabdomyolysis can occur in a few cases. Gas gangrene caused by Clostridium perfringens is a severe condition that is occasionally associated with sepsis resulting in fatality. Mycoplasma pneumoniae infection is often widespread and involves the respiratory and nervous systems, as well as the skin and muscles.
Fungal infections are also known to occur in immunocompromised patients. Cryptococcus, Candida and Aspergillus are common causative organisms.
