September 1st 2008Within the past decade, the incidence of methicillin-resistantStaphylococcus aureus (MRSA) has increased significantly,spreading from the hospital to the community setting. Patientswith skin infections whose condition is stable should be treatedwith antibiotic therapy as well as with incision and drainage,whereas patients with severe disease require hospitalizationand intravenous therapy. In addition to community-acquiredMRSA, a new strain of Clostridium difficile, BI/NAP1, has led toclinical challenges in infectious diseases medicine. The strainhas been associated with recurrent infection; more severe diseasethat mandates urgent colectomy; and dramatically highermortality in vulnerable populations, such as older adults. Oralvancomycin, rather than metronidazole, may be slightly moreeffective in patients with severe disease. Also, new strains of Chlamydia and Treponema are posing potential complications tothe treatment of sexually transmitted diseases such that cliniciansneed to be judicious in selecting antibiotic therapy in accordancewith factors related to geography and patient population.[Infect Med. 2008;25:421-424]