The MRSA endemic in healthcare facilities
MRSA is a mutated form of a bacteria called Staphylococcus Aureus. The mutation makes it resistant to the antibiotic methicillin thus more difficult to treat. It is now accepted that early identification of colonized patients and prompt implementation of of contact precautions are the key to successful prevention of the transmission of MRSA infection in hospitals due to it’s extremely contagious nature. Patients infected with MRSA often have to be isolated and treated specially, not only increasing the cost of their hospital stay, but also reducing the quality of stay for the patient.
Current guidelines for the prevention and control of MRSA transmission advocate selective screening of ‘at-risk’ patients. These guidelines do not recommend screening of all admissions to the hospital on the grounds of lack of evidence for clinical usefulness and cost effectiveness.
Why the current guidelines need to be changed
One study study done in an hospital with approximately 500 beds catering to roughly 300,000 people in the south of London examined compliance to these guidelines. They immediately noticed poor compliance especially in regards to emergency admissions. Two of the most common reasons for this was staff forgetting to screen and difficulties in deciding who really “at-risk” needing to be screened.
In this hospital, adult emergency admissions account for nearly 84% of all adult admission. The researchers decided to improve compliance by screening almost all (80%) emergency admissions to the hospital for roughly a year. Patients were screened for MRSA in the emergency department prior to admission by taking nose swabs from patients and testing for MRSA colonization. Roughly 8.6% of all admissions tested positive for MRSA colonization.
The study also found that there was little correlation between the proportion of patients thought to be “at-risk” and MRSA colonization further discrediting the current guidelines.
Screening all patients for MRSA is found to be effective
MRSA colonization rate in the patients at the time of admission fell from 12.9% to 6.5% during the period of the study. The researchers mostly attributed this to the infection control practices established because of the increased screening. When a patient was found to be positive for MRSA colonization, they immediately began treatment and enhanced isolation precautions were used including giving the patient a private room if one was available.
This study relied on using a different test for MRSA, specifically selective enrichment broth, rather than the NAAT test suggested by the guidelines. While the NAAT test is quicker and more specific, it is on average nine times more expensive in total cost than using the broth. The broth test results can be confirmed within a day which is enough time to implement effective infection control practices.
What does this mean for hospitalized patients?
Patients in hospitals that screen more incoming patients for MRSA have lower rates of hospital-acquired MRSA infections, increasing the safety of their stay.
Further studies need to be done confirm these findings in other hospitals where the rates of people colonized with MRSA pre-admission differ.