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MRSA and VRSA

By mikethemadbiologist on December 26, 2006.

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.'

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antibiotics
microbiology
MRSA
public health
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Medicine

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So this is why I have a languishing inner ear infection that's gone on for months, even though I've taken:

Maxxide - did nothing but make the vertigo worse and tank my blood pressure.

Medrol - no effect

Ativan - useless

Prednison 60mg day - so far no effect.

Even had MRI done. Non-conclusive.

It's an infection - I know this because I know the source, my rotting wisdom teeth that were taken out not long ago.

But everyone is loathe to prescribe antibiotics. It's really starting to piss me off.

Given the medicines your doctor has tried, it is pretty clear that they do not believe it is infectious in nature.. Doctors are not against prescribing ABX, only prescribing ABX inappropriatly.

You could give tigacycline in an outpatient/ambulatory infusion clinic, since it's every 12 hours. It's not terribly convenient, and there are always insurance issues (hoops to jump through to get them to cover it, usually), but it's usually cheaper than a hospital stay.

VRE is a pretty big problem in many hospitals, but with the increase in CA-MRSA, not to mention overuse and misuse* of vanco, VRSA could be a big, nasty problem. I'd heard of maybe a half dozen incidents worldwide 2-3 years ago, but apparently it's gone up since.

*underdosing, continuing use when MRSA is ruled out, other uses without indications

I am currently receiving IV infusions of Tigacycline daily. Three days a week I also receive infusions of Amikacin. I have developed pitted edema in my ankles and wonder if this is caused by the Tigacycline.I never had it before. I have been on these medications for 1 month and the swelling started 3 days ago.

By Jackie Harrison (not verified) on 07 Feb 2007 #permalink

Don't you think daptomycin is also a reasonable treatment option for MRSA or perhaps VRSA? (Okay, maybe not hVISA) As long as it's not a respiratory infection I would probably prefer daptomycin to linezolid or tigecycline given its cidal in vitro activity.

I'm reluctant to give medical advice, so just consider this one bit of anecodotal data. I'm also not medically trained so this description may be poor.

I developed two sores on my legs which were originally suspected of being brown recluse bites, as the inflamation and necrosis were very similar to photographs of known bites. As it turns out, these were, evidently, wounds that had been infected with some sort of staph infection (MRSA, MSSA, VRSA).

A number of antibiotics were taken over the course of a year, with little to no change.

Frustrated at the prospect of never being able to wear shorts again (and, of course the natural health-related fears of having a persistent condition for well over a year), I tried a simpler approach.

One of the sores is now mostly healed, though a mildly ulcerated red patch is still visible. The other is nearly to that stage. Neither site is painful and there's only mild itching on rare occasions with the second sore.

The treatment? Scrub the area clean with hot water, removing any dead tissue and discoloration and then apply rubbing alcohol - liberally.

Any update of successfully used antibiotics against VRSA?

Trimethroprim/sulfamethoxazole, linezolid, quinupristin/dalfopristin and daptomycin "can be considered in treatment of VISA and VRSA". Tigecycline was found to be active against VISA. Ceftobiprole was active in MRSA and VRSA. These are reported cases so far.

Trimethroprim/sulfamethoxazole, linezolid, quinupristin/dalfopristin and daptomycin "can be considered in treatment of VISA and VRSA". Tigecycline was found to be active against VISA. Ceftobiprole was active in MRSA and VRSA. These are reported cases so far.