Methicillin-resistant Staphylococcus aureus (MRSA) is a type of staph bacteria that has developed resistance to many common antibiotics, including methicillin and penicillin. This resistance makes MRSA infections significantly more difficult to treat compared to ordinary staph infections. MRSA management involves two distinct goals: clearing an active, symptomatic infection and eliminating the bacteria when it is residing in the body without causing illness, a process known as decolonization.
Treating Active MRSA Infections
When MRSA causes a symptomatic illness, such as a skin abscess, pneumonia, or a bloodstream infection, it requires prompt medical intervention. Managing an active infection begins with obtaining a definitive diagnosis, typically through a swab or culture of the infected site. This testing confirms the presence of MRSA and determines its specific resistance pattern, guiding the selection of the most effective antibiotic.
Treatment is highly tailored to the location and severity of the infection. For simple skin and soft tissue infections, providers often start with a non-antibiotic approach, such as surgically draining the pus from an abscess, which frequently resolves the issue. If the infection is more widespread, severe, or involves deeper tissues, specific, potent antibiotics are necessary. These medications may need to be administered intravenously for serious infections like sepsis or bone infections. The duration of therapy can range from a few days to several weeks, and patients must complete the entire prescribed course to ensure the bacteria are fully eliminated and prevent further resistance.
Strategies for MRSA Decolonization
For many people, MRSA lives harmlessly on the skin or inside the nose, a state known as colonization, which acts as a reservoir for future infections or transmission. Decolonization is the process of eradicating this asymptomatic carriage, which differs fundamentally from treating an active infection. This protocol is recommended for individuals with recurrent MRSA infections or those preparing for certain surgeries where the risk of infection is high.
The standard medical decolonization protocol targets the most common colonization sites: the nose and the skin. This regimen involves a combination of a topical antibiotic ointment and an antiseptic body wash, usually lasting for five to seven days. The nasal application typically uses a prescription antibiotic cream, such as mupirocin, applied inside both nostrils twice daily to clear the bacteria from the primary carriage site.
The full-body portion of the decolonization involves washing daily with an antiseptic solution, most commonly Chlorhexidine gluconate (CHG). The wash is applied to the entire body, from the neck down, and often needs to remain on the skin for a specified contact time, such as two minutes, before rinsing. Strict adherence to this multi-step regimen is necessary for a successful outcome, as missing applications or not following instructions precisely can lead to treatment failure or resistance.
Environmental and Personal Hygiene for Eradication
Medical decolonization must be paired with hygiene measures to prevent the patient from immediately becoming re-colonized from their surroundings or personal items. The most important measure is hand hygiene, involving frequent washing with soap and water or using an alcohol-based hand sanitizer. This practice should be emphasized, especially after touching the nose, changing bandages, or using the bathroom.
Environmental cleaning focuses on surfaces that are frequently touched or come into contact with bare skin. This includes doorknobs, counters, bathtubs, sinks, and shared gym equipment. Regular cleaning with a detergent-based cleaner or a standard household disinfectant is effective at removing MRSA from these surfaces.
Personal items that touch the skin should not be shared, including towels, washcloths, razors, and bed linens. Laundry should be managed carefully during the decolonization period, with clothes, sheets, and towels being changed daily. Although routine laundry with detergent is sufficient, using hot water and a hot-cycle dryer provides an extra layer of precaution against surviving bacteria.
Confirming Eradication and Monitoring
After completing the decolonization regimen, confirming the elimination of MRSA is the final step. Eradication is typically verified through follow-up screening cultures, which involve swabbing the common colonization sites, primarily the nose, groin, or armpit. These screening swabs are usually taken a few days to a week after the final application of treatments to allow the body to clear any residual medications.
A negative result on these follow-up tests indicates that the decolonization was successful at that time. However, a negative test result is not a guarantee of permanent clearance, as recolonization remains a possibility, especially for those with ongoing exposure risks or underlying health conditions. Recurrence rates can be significant, with most recolonizations occurring within the first nine months following treatment. Continued vigilance with personal and environmental hygiene is necessary to maintain a bacteria-free state and prevent future infections.