MRSA infection in obstetrics and gynecology

Although virtually all clinicians know the term MRSA (methicillin-resistant Staphylococcus aureus) and a growing number of patients fear its destructive path,^1-3 there is still much for us to learn about the infection, and much practical advice that can help thwart the growing threat. In January 2008, a policy paper on antimicrobial agent resistance published by the Infectious Diseases Society of America described MRSA infection as a global pandemic.⁴ In the United States, the Centers for Disease Control and Prevention (CDC) recently reported 2005 surveillance data showing a significant increase of invasive MRSA disease during the prior 5 years, with an estimated 94,360 cases and 18,650 national deaths associated with MRSA.⁵ To put these numbers into perspective, it helps to realize that in 2005, there were more estimated deaths from MRSA than from HIV-AIDS. It's not surprising then that the CDC has labeled invasive MRSA as a major health concern that (at least in 2005) remained largely associated with health-care contact.⁵

MRSA poses at least two critical questions for all practicing physicians:

(1) How can I prevent the spread of MRSA in my practice?

Hand hygiene and nasal swabbing can make a difference

Preventing the spread of MRSA in one's own practice requires vigilant hygiene because MRSA is transient on the hands and can be removed by regular hand washing or by using alcohol-based disinfectant gels.⁶ Be sure to cleanse your hands before and after each patient contact, and before performing any invasive procedure, including amniocentesis.

For broader, population-wide impact, health-care organizations need to get involved, implementing large-scale programs to reduce the spread of MRSA. The CDC guideline for managing multidrug-resistant organisms (MDROs) requires that these organizations know the incidence or prevalence of the infection for each organism, and if they cannot show that their programs are significantly decreasing infection rates, the organization must deploy more intensified measures, which translates into expanded active surveillance.⁷ At NorthShore University HealthSystem (NorthShore; formerly Evanston North-western Healthcare [ENH]), we began an intensified surveillance program in August of 2005 that consisted of performing nasal swab testing (the anterior nares is the usual site of MRSA colonization) on all admissions to our three hospitals, followed by isolation and decolonization of patients found to be carriers.⁸ This comprehensive program has been successful in reducing health-care-associated MRSA infections by 70% during the 21-month intervention period evaluated, when compared to before the program was introduced. Our program was also cost-effective because it avoided the expenses normally incurred for treatment of health-care associated MRSA disease, more than offsetting the costs of the MRSA surveillance and decolonization program.⁹

Understanding the risks to ob/gyn patients

In obstetrics and gynecology, there are two main groups of patients, each presenting differing challenges. The typical gynecologic patient has a similar risk of MRSA infection as does any other patient-and those risks are determined by the procedure she will undergo, as well as her age, underlying diseases, overnight health-care facility admission in the prior year, and their history of infection or colonization with MRSA.^5,8

Ob patients face their own risks. In 2005, researchers suggested that MRSA is an increasing cause of infection during pregnancy,¹⁰ steadily increasing from two infected patients in their practice during 2000 up to 17 cases for the first 7 months of 2004. As expected for community-associated MRSA (CA-MRSA), most of their cases (96%) involved skin and soft tissue infection with the commonly infected sites being extremities, buttocks, and breast, respectively.¹⁰ There are some continuing case reports of CA-MRSA causing maternal infection after normal vaginal delivery, but to date they remain rare.^11,12