From the archives, I’m reposting this article about MRSA and VRSA. I’ve made some changes because the science and medical practice have changed.
The Chicago Tribune reports that three children died from toxic shock syndrome caused by methicillin resistant Staphylococcus aureus (“MRSA”). Toxic shock syndrome is not typically associated with MRSA. What’s worse is that these infections were “community-acquired” (CA-MRSA) In other words, the kids were not infected in the hospital-many staph infections are hospital acquired due to puncturing the skin barrier (e.g., catheters, IVs, surgery). MRSA, because of hospital antibiotic use, is particularly prevalent in hospitals. However, these children came down with MRSA outside of the hospital. This means that the non-clinical environment is serving as a ‘reservoir’ of MRSA. CA-MRSA is not an isolated phenomenon; it’s becoming more and more common.
About 40-60% of staph infections can be treated with methicillin (or oxacillin; the success rate is much higher for community acquired staph). However, given the high level of both hospital MRSA and CA-MRSA, methicillin is often not used at all, particularly in critical situations.
This leaves vancomycin as the standard treatment for MRSA. Unfortunately, we are now seeing more incidents of VRSA (vancomycin resistant staph). Last week, I received a call from someone (not a medical professional) who was frantic because a friend had VRSA, and his doctors didn’t know how to treat it (note: these aren’t necessarily ‘bad’ doctors; the amount of information that a general practioner or a surgeon has to keep up with staggering. The accepted procedure for MRSA is treatment with vancomycin; tigecycline and linezolid have been recently introduced).
Currently, there are two antibiotics that could be used against VRSA: tigecycline and linezolid. While tigecycline can be used to treat some infections (skin and abdomindal), it is not used to treat bloodstream infections. Tigecycline also must be administered intravenously, requiring a hospital stay during the course of therapy (usually several days). This is very expensive–just the hospital stay alone can cost several thousand dollars.
Linezolid can also be used against VRSA, but it is not approved for use in children under 18, and can have serious side effects; linezolid resistance, while rare, is still observed at frequencies ‘higher than anecdote.’