What to Do When One Bacterial Scourge Begets Another

With the significant rise in methicillin-resistant Staphylococcus aureus (MRSA) infections, a small rise in the number of cases of Clostridium difficile colitis appears to be an unfortunate but unpreventable consequence of using the few effective antibiotics remaining that can be prescribed in the outpatient setting. Can Dr Gregory Rutecki (What Hath Antibiotics Wrought? The Nightmare of Clostridium difficile Colitis, CONSULTANT, September 1, 2006, page 1104) recommend a treatment for MRSA infections that would prevent the development of C difficile colitis?
— Robert Walantas

You bring up a sticky issue that is rapidly increasing in importance: another bacterial scourge, MRSA. Your remarks are right on target and consistent with recent literature, which should serve as a warning. One expert has expressed concern that a new influenza epidemic would trigger MRSA infections, many of them fatal.¹ Another study reported that MRSA was the most common cause of skin and soft tissue infections in ambulatory settings in 11 US cities--and that 57% of the isolates in these infections were resistant to the antibiotics first prescribed.² What should we do to balance the risk of MRSA, antibiotic use, and the specter of fatal C difficile colitis?

First, in the case of community-acquired MRSA, many patients are cured by drainage of the infection without antibiotics. With respect to concerns about C difficile, that is good news. An antibiotic combination that is successful against community-acquired MRSA includes rifampin and trimethoprim/ sulfamethoxazole. If a patient is allergic to either of these agents, clindamycin or doxycycline can be an alternative. However, all antibiotics can lead to the development of C difficile colitis--that is the rub.

Hospital-acquired infections are still a challenge and require consultative assistance with an armamentarium that includes vancomycin and newer agents, such as linezolid. Intensive therapies in seriously ill patients carry an increased risk of C difficile colitis as an unavoidable by-product of increased resistance.

The bottom line, although it will not be easy, is that we in primary care must limit our use of antibiotics as much as possible, prescribing them only when they are really needed and for no longer than they are needed.