What is MRSA and Is it Dangerous?

There is a lot of information and concern in the community regarding MRSA. This overview is intended to give you some background information and general guidance. Please feel free to contact our office if you have additional questions or concerns.

MRSA stands for “Methicillin-Resistant Staphylococcus Aureus.” Staph aureus is a bacteria that has been around for decades. It often lives on the skin of normal, healthy people. Many people also carry this bacteria in their anterior nostrils. When someone has a breakdown in the integrity of their skin (from a scratch, injury, rash, etc.), the normal bacteria that live on the surface of their skin now have an opportunity to get deeper and set up an infection. The same thing can happen when children pick their nose and then scratch an itchy rash.

For many years, one of the most common causes of simple skin infections has been staph aureus. Those infections have been relatively easy to treat with a variety of antibiotics, including some in the penicillin and cephalosporin classes (Augmentin and Keflex, for example.) But all living organisms learn to adapt in order to survive. Now some of those staph aureus have become “Methicillin resistant.” That is to say, when you test the sensitivity of those bacteria to antibiotics in the laboratory, the growth of the bacteria is not hindered by methicillin.

Genetically, there are two distinct groups of MRSA bacteria. The first one to emerge was something we first saw in the health care setting (hospitals, nursing homes, etc.) This group of MRSA continues to be problematic in that it tends to be resistant to many antibiotics that are commonly used. Recently, there has been identification of a separate MRSA that is found in healthy patients in the community. We call this “Community acquired” MRSA or CA-MRSA. In some communities, if you did cultures of the skin or anterior nostril on healthy patients, 40% of the staph aureus would be CA-MRSA. Luckily, this form of MRSA is very sensitive to other common antibiotics like Trimethorpim/Sulfa (commonly also knows as Bactrim or Septra) and Clindamycin (commonly known as Cleocin.)

CA-MRSA are not “superbugs.” They are not more deadly than the regular staph aureus that has been around for a long time. We simply need to be on the look out for them, since it changes the way physicians choose antibiotics. You might ask why we don’t just treat all skin infections with Bactrim or Cleocin. There are actually two reasons not to use that tactic. One is that Streptococcus is a second bacteria that can cause skin infections and it has never been particularly sensitive to Bactrim. Secondly, we don’t want to overuse those medicines and create a problem where the bacteria are one step ahead of us, then we run out of antibiotic options.

If you have a superficial skin infection, you may notice us doing more cultures of the area and sending them to the lab. We want to have good information on what bacteria are causing your specific infection so that we can make the most appropriate antibiotic choices. If the infection is very mild or superficial, it is recommended that we attempt to treat with topical antibiotic creams only. Muciprocin (bactroban or altabax) is effective for many simple skin infections and even covers CA-MRSA.

What if someone in your family gets recurrent boils or superficial skin infections that have been identified as CA-MRSA? Most experts would agree that treating with topical muciprocin at the onset of symptoms is the best approach. Some would suggest that you also treat the skin in the inside of the nostrils, since the CA-MRSA might be “hiding” there as well. Appropriate oral antibiotics will be used if we are concerned that this infection is potentially deeper than just on the surface of your skin, or is not responding to topical therapy.

Some folks have tried all kinds of bleach baths, etc. In almost all patients, that only temporarily stops your skin from having CA-MRSA as its normal bacteria, and within months of stopping, those bacteria grow back. We believe schools that closed and cleaned all their surfaces did so unnecessarily. As soon as the regular student population returns to school, those areas will be re-colonized with MRSA since a certain portion of the student population is normally colonized with those bacteria. Having said that, it is always smart for patients to not share towels, sporting equipment, etc. because that promotes the sharing of bacteria.

If someone in your family has been identified as having MRSA, please mention that fact to any treating healthcare provider. It may change which antibiotics we use to treat an infection, and it may make us reach for a culture swab prior to starting antibiotics in the first place.