Summary And Review Of The Article On Methicillin Resistant Staphylococcus Aureus (MRSA) In The Intensive Care Unit

In the journal, “Methicillin resistant Staphylococcus aureus (MRSA) in the intensive care unit”, by AS Haddadin, SA Fappiano, and PA Lipsett seeks to address how MRSA, a major nosocomial pathogen has caused severe morbidity and mortality worldwide. In fact, Staphylococcus aureus is liable for 29%-35% of all clinical isolates in countless American and European hospitals. Two million patients develop an infection that has been attracted by hospitals in the US and 60% of those are caused by organisms that are resistant to antibiotics. The research problem being addressed is whether the drugs of choice like glycopeptide, vancomycin, or teicoplanin would be a better option rather than the newer alternatives which are in preclinical evaluation. It is recognizable from the abstract that the issue was not going to be a simple matter. However, the journal was by far critically explained through exceptionally specific details.

The mechanism of resistance in medication works as follows, if an organism was subtle to an antibiotic and then becomes resistance that is known as “acquired antibiotic resistance”. However, a relative acquired resistance is the increase effect obtained over a period of time of an organism to a certain type of antibiotic. Both may occur when a single step mutation during or after the treatment increases the MIC (minimal inhibitory concentration) to a very high dose. MRSA is a gram-positive organism that has specific assessment to determine its species. For instance, catalase and coagulate. It also has strains containing the mecA gene (<2%) which are likely to be harmed by methicillin; it encodes with a penicil- lin bind protein, PBP2a, with low affinity for all β-lactams. Therefore, making it the most common to intervene with the mecA gene.

A few intermediate resistances to vancomycin have also been recognized in Europe, Asia, and the US. leading to more than eight unknown cases worldwide! Generally speaking in April of 1996 there was a fourth case of resistance to vancomycin (VISA). In addition, these same pathogens have also become resistant to teicoplanin, a medication mostly used in Europe. Previous hospitalization, the presence of invasive indwelling devices, and long stays in ICU are some of the risk factors for MRSA. Staphylococci is found mainly on the inguinal, perianal areas and anterior nares, as well as the axillae. In fact, about 85% of carriers can be recognized with a swab taken from the anterior nares and 25% were found on hospital employees. Although, there seems to be a high percentage to those stated above, the highest carriers come from drug users whom have to inject including insulin dependent diabetes mellitus as well as long term intravascular catheters. With that being said, the number of MRSA carrier patient days/total number of patients was the only independent predictor of MRSA infection in a recent study.

Scientist Jerinigan and colleagues stated that patients who were separated from other people and in isolation had drastically lower chances of transmissions a day. About 0. 009 possible transmissions in a day compared to those patients who were not. Those patients with both cirrhosis, following an early liver transplant are at major risk of a MRSA infection. Patients in ICU are in critical care with open wounds, drains, and intense machines that monitor the body and cause a rupture on the skin increasing the development of infection. Since MRSA is a widespread epidemic in most of all hospitals worldwide strategies of control are needed as soon as possible. Some of the control methods for MRSA in ICU are screening patients, handwashing of hospital personal, environmental cleaning, gowns, gloves and single room isolation. Shocking enough, a recent study was done were 26% of computer keys and 15% of sink faucet handles reported a higher risk of infection than in ICU. Proving that it does not have to do with direct contact in a patient’s room but instead all around. However, it has been recognized that some MRSA isolation and infection techniques have been successfully controlled in some areas but, yet some individuals have distrusted both the effectiveness as well as the cost of these infection control procedures.

Over a four-year period in medical ICU, 7. 9% of 3686 admissions developed MRSA and in this same study only a few MRSA carriers about 26% of them had secondary colonization or infection and only 19. 5% out of 133 were at risk of infection. Among all infecting species in nosocomial (ICU) pneumonia, staphylococcus aureus ranked at 31. 7% leaving enterococci at only 5. 4%. Vancomycin is by far used to treat different types of infections like pneumonia and meningitis. However, it penetrates poorly into the bile and aqueous humor. When the meninges are inflamed it is very difficult for the penetration into the cerebrospinal to occur. In fact, it ranges from 7% to 21 % when the desired amount is about 25. In addition, it is also eliminated by glomerular filtration were 80 to 90% of it ends up in the urine anyway.

Furthermore, it cannot be given intramuscularly because of the extreme discomfort caused to the injected site and orally is unsuccessful as well because it’s absorbed poorly from the gastrointestinal tract. As far as teicoplanin, a glycopeptide antibiotic almost like vancomycin but not quit, has a greater lipophilicity, slow release from tissues and water solubility at physiological ph. Is used as an alternative drug to vancomycin in Europe. However, in certain parts of Europe like England for example it has been proven that resistant strains have been discovered with vancomycin. However, the involvement of 108 adults in ICUs of 41 US hospitals demonstrated that vancomycin was mostly connected to isolation of MRSA and central line associated bloodstream infections. Vancomycin combined with aminoglycoside for example also have no interaction with the majority of S aureus strains, including both MSSA and MRSA.

Oxazolidinones (Linezolid) is a new antimicrobial agent discovered in 1987 that’s under preclinical evaluation. It has inhibitory activities agent’s gram-positive bacteria of those found in MRSA, VISA, vancomycin resistant enterococci, and penicillin resistant S pneumoniae. In addition, it also directly involved in binding mRNA during the start of translation. Therefore, because of that unique factor, no cross resistance with other available antimicrobials may occur. Though, Linezolid showed efficiency with MRSA, a trial was conducted in ICU patients for treatment of any other anatomic infection and the results have not yet been published except in abstract form.

There is also Quinupristin, a drug that binds to 50S ribosomes. When it starts to establish resistance to at least one of the factors in Quinupristin the organism will eventually not be killed but continue to be inhibited instead. The results to all the newer alternatives show that studies will further because there have been positive result outcomes with the breakdown of each antimicrobial agent. The epidemiology of antibiotic resistance on MRSA in the ICU is a crucial topic. Antibiotics are often prescribed to patients for no useful purpose like a cold, flu or diarrhea. In fact, the public is now referring to them as “germs or bugs” therefore, society has engraved a mentality that medication should be taking advantage of but not realizing that this is harming humanity. It is causing the epidemiology that is currently occurring were bacteria is taking over without having a defensive mechanism to shut down to keep growing and eventually drive this high-tech world into the dark ages of medicine.

Continuing research, prohibiting the over use of medication if not needed and making sure ICU unites are at the top of their game with cleanliness, will defiantly start to make a difference within MRSA resistance antibiotics not to completely stop it but slow it down.

Overall, I chose this article because it was very straightforward with its details. A lot of information was given but well organized, the journal not only explained what MRSA in the intensive care unit is like but also had visuals like charts that disclosed percent totals of infected species in ICU pneumonia. It even had key points that gave more information on that certain section. In addition, there was a lot of research done throughout, not only one but many ICU units to compare the stability of the drug. The journal demonstrated that research studies are also taking place with new drugs but have yet to be published as they only have an abstract.

Lastly, MRSA is a bacterium that is of interest to me because of my ultimate goal in dermatology. Therefore, understanding it will only better my chances of being well rounded in that area when the time comes to put into practice what I have learned thus far.