How is MRSA diagnosed?

The first step in diagnosing MRSA is noticing that an infection is present. This infection may appear as an abscess (a tender mass, surrounded by pink or red coloring of the skin), surrounding a wound, where there's pus, or could present as sepsis (systemic infection). Signs of infection include redness, tenderness, presence of pus, swelling and warmth. Once an infection is found, antibiotics are usually given to fight the bacteria causing the infection. If the infection persists and does not make any improvements, a sample of fluid from the area will be tested to see if MRSA is present. 

What a MRSA infection may look like: 

                                 

For more details about how the swab is tested, take a look at this website: 

http://www.emedicinehealth.com/mrsa_infection/page7_em.htm

Certain laws require hospitals to do routine screening for MRSA upon admittance, and/or before discharge. This screening is not to find an active MRSA infection, but to see if patients are carriers of MRSA. As we talked about previously, many people carry MRSA on their skin, or in their nose and it's completely harmless. However, the screening is done to prevent transmission of MRSA to people with weakened immune systems, pregnant patients, or to yourself through a surgical wound for example. This website explains what one hospital (UCSF Medical Center) does with the knowledge from a routine MRSA swab. 

http://www.ucsfhealth.org/education/mrsa_testing/

Here's a great video showing how a swab from your nose is used to find MRSA: 

References: 

MRSA Causes, Symptoms, Treatment - MRSA Infection Diagnosis - eMedicineHealth. (n.d.). Retrieved April 23, 2015, from http://www.emedicinehealth.com/mrsa_infection/page7_em.htm

MRSA Testing. (n.d.). Retrieved April 23, 2015, from http://www.ucsfhealth.org/education/mrsa_testing/

The pathophysiology of MRSA (But what in the world does that mean!?)

What does pathophysiology mean? Here's the definition from Merriam- Webster: "the physiology of abnormal states; specifically :  the functional changes that accompany a particular syndrome or disease". So, when we say what is the pathophysiology of MRSA, we're asking about the changes in the body that happen with a MRSA infection. 

Although the second half of the video goes into a bit of a tangent around medical waste and picking your nose, the first half gives a simplistic view of what a bacterial infection looks like. 

As the video shows, MRSA is especially concerning because of its resistant nature. Well, how does the resistance happen? How does a bacterium get so hardcore that it can fight off most antibiotics? Well, I think this visual explains it well: 

Essentially, when the bacteria multiply, like within our own cells, random mutations occurs. Some mutations do nothing, but some help the bacteria survive the attacks from medicine. Eventually, as those mutated bacteria continue to survive they end up being the only ones left and all of the bacteria can fight back against the medication that once killed them. 

If you're interested in reading a more detailed description of how this process happens in MRSA, please read this article: 

Pathogenesis of Methicillin-Resistant Staphylococcus aureus Infection

References: 

Clinical Infectious Diseases. (n.d.). Retrieved April 18, 2015, from http://cid.oxfordjournals.org/content/46/Supplement_5/S350.full

(n.d.). Retrieved April 18, 2015, from http://www.merriam-webster.com/dictionary/pathophysiology

What do the statistics say?

According to the Center for Disease Control, MRSA infections are on the decline. Although MRSA still poses a threat in both healthcare settings and the community, it is encouraging to look at some statistics that show progress in fighting the infection. 

"Invasive MRSA infections that began in hospitals declined 54% between 2005 and 2011, with 30,800 fewer severe MRSA infections. In addition, the study showed 9,000 fewer deaths in hospital patients in 2011 versus 2005." 

(Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 30 Apr. 2014. Web. 11 Apr. 2015. <http://www.cdc.gov/mrsa/tracking/index.html>)                                    

Although data shows improvements in the rate and outcomes of MRSA infections, we still want to know how to resist getting an infection. So, who should be especially careful? Well, for hospital acquired MRSA, the National Institute of Health states that the elderly, patients receiving dialysis, those with venous catheters, or weakened immune systems are especially susceptible. As far as community acquired MRSA (which has only been a problem since the 1990's), people who have close skin-to-skin contact are at a higher risk, as well as children. The NIH recommends paying close attention to things like small scratches, or bug bites to note any signs of infection early on. Research is continuously being conducted to find more patterns and insight into why some people get MRSA and others don't. Interestingly, high outbreaks have occurred in Alaska, Georgia and Louisiana, although the reasons are unknown. Another study found that there was a seasonal increase in community MRSA in the late summer (especially in children)and an increase in hospital MRSA in the winter which they guessed may be due to shifts in the way antibiotics are prescribed.

Here's a video that provides some great information on MRSA and BONUS, although the content may make some squeamish at least the music is rather meditative.

 

Resources: 

Centers for Disease Control and Prevention. Centers for Disease Control and Prevention, 30 Apr. 2014. Web. 11 Apr. 2015. <http://www.cdc.gov/mrsa/tracking/index.html>.

"American Journal of Epidemiology." The Changing Epidemiology of Methicillin-Resistant Staphylococcus Aureus in the United States: A National Observational Study. Web. 11 Apr. 2015. <http://aje.oxfordjournals.org/content/177/7/666.long>.

"Antimicrobial (Drug) Resistance." Transmission, Methicillin-Resistant Staphylococcus Aureus, Antimicrobial Resistance. Web. 11 Apr. 2015. <http://www.niaid.nih.gov/topics/antimicrobialResistance/Examples/mrsa/Pages/transmission.aspx>.

Let's Start With The Basics

Question: What does MRSA stand for?

Answer: Methicillin Resistant Staphylococcus Aureus

Although many of us may have heard of MRSA (pronounced mer-sa), we may not really know what it stands for, or what the implications are.


Question: What does Methicillin Resistant Staphylococcus Aureus mean exactly?

Answer: This is a type of bacterial staph infection (Staphylococcus Aureus) that is resistant to antibiotics (Methicillin) that normally treat other staph infections .


Question: So, how do people get MRSA?

Answer: People often acquire MRSA in a hospital, or clinical settings, although some people also get it in the community. Staph are bacteria that are normally found on the human body (often in the nose), but don't cause harm unless they enter the body and cause infection- usually through a cut. This particular type of Staph bacteria causes a greater problem because it is resistant to treatment that cures other type of staph infections. MRSA is spread through contact, so can be passed on by touch, or from a surface. People with weakened immune systems are more susceptible and those in the hospital can acquire MRSA through invasive procedures, or wounds for example. People with healthy immune systems in the community may contract MRSA through close contact like with certain sports, or people who share living quarters. It is estimated that about 2% of the population carry MRSA, although many of those individuals are not infected.


Question: So what happens if I get MRSA? How will it be treated?

Answer: Although MRSA is resistant to antibiotics commonly used to treat staph, other antibiotics still work. Many of these, however, will need to be given through an IV, so the treatment would need to be completed in a healthcare facility. MRSA continues to gain resistance to more and more antibiotics, so it is important to remember to use the full course of an antibiotic. When people do not take the full course, the bacteria are more likely to acquire resistance as they may be only weakened, rather than completely killed.


Here's a great short video that explains MRSA further:

Sources:
MRSA Diagnosis and Treatment: Antibiotics, Drainage, and More. (n.d.). Retrieved April 4, 2015, from http://www.webmd.com/skin-problems-and-treatments/understanding-mrsa-detection-treatment

MRSA infection. (n.d.). Retrieved April 4, 2015, from http://www.mayoclinic.org/diseases-conditions/mrsa/basics/definition/con-20024479