Rick Tosti,Brian T. Samuelsen,Samantha Bender,John R. Fowler

John Gaughan,Alyssa A. Schaffer,Asif M. Ilyas

Background: Methicillin-resistant Staphylococcus aureus has been the most commonly identified pathogen in hand infections at urban centers, but the evolving antibiotic sensitivity profiles of methicillin-resistant Staphylococcus aureus are not known. The purposes of this study are to determine if multidrug resistance in methicillin-resistant Staphylococcus aureus is emerging and to provide current recommendations for empiric antibiotic selection for hand infections in endemic regions.

Methods: An eight-year longitudinal, retrospective chart review was performed on all culture-positive hand infections encountered by an urban hospital from 2005 to 2012. The proportions of all major organisms were calculated for each year. Methicillin-resistant Staphylococcus aureus infections were additionally analyzed for antibiotic sensitivity.

Results: A total of 683 culture-positive hand infections were identified. Overall, methicillin-resistant Staphylococcus aureus grew on culture in 49% of cases; the annual incidence peaked at 65% in 2007. Over the study period, methicillin-resistant Staphylococcus aureus was universally resistant to penicillin, oxacillin, and ampicillin. Clindamycin resistance significantly increased, approaching 20% by 2012 (p = 0.02). Levofloxacin resistance linearly increased from 12% to 50% (p < 0.01). Resistance to trimethoprim-sulfamethoxazole, tetracycline, gentamicin, and moxifloxacin was only sporadically observed. Resistance to vancomycin, daptomycin, linezolid, and rifampin was not observed.

Conclusions: Significant increases in resistance to clindamycin and levofloxacin were observed in recent years, and empiric therapy with these drugs may have limited efficacy, especially in urban centers.