Study: Muscle Infections Caused By CA-MRSA

U.S. researchers say they have determined antibiotic-resistant bacteria are responsible for an increase in muscle infections.

Physicians at Texas Children’s Hospital in Houston found two bacterial muscle infections common in tropical countries are becoming more frequent occurrences — along with the emergence of community-acquired methicillin-resistant Staphylococcus aureus, or CA-MRSA.

Pyomyositis is an acute bacterial infection of skeletal muscle that produces an abscess within the muscle. Myositis is also a muscle infection, but does not form an abscess.

The study’s authors investigated 45 cases of pyomyositis or myositis in otherwise healthy children hospitalized at the hospital from 2000 through 2005. Sixteen of the cases were caused by CA-MRSA and 10 by CA-MSSA (methicillin-susceptible Staphylococcus aureus).

We’re seeing an increasing number of muscle infections that is clearly associated with an increase in MRSA, said lead author Dr. Pia Pannaraj. Physicians need to be aware that this is a possibility and consider initial treatment with an antibiotic that covers MRSA, particularly if they live in a region where methicillin resistance is present.

The study appears online in advance of publication in the Oct. 15 issue of the journal Clinical Infectious Diseases.