Predictors of Recurrent Staphylococcus aureus Skin Infection After Treatment: Host, Behavioral, and Pathogen Level Factors
Many patients suffer from recurrent Staphylococcus aureus infections, however, there are few longitudinal data examining predictors of recurrences and few data holistically incorporating the competing host, behavioral, and pathogen factors that may contribute to recurrent infections.
Methods: We longitudinally studied adults and children with S. aureus skin infections in Los Angeles and Chicago. We surveyed subjects and their household contacts for S. aureusbody colonization, household fomite contamination, behavioral and clinical factors at months 0, 3, and 6. Using repeated measures modeling, we examined host, pathogen, behavior, and clinical factors associated with recurrent skin infection.
Results: Among 330 index subjects, 182 (55%) were infected with an isolate of the USA300 genetic background. Thirty nine percent reported a recurrent skin infection by 3 and 51% by month 6. Among 588 household contacts, 10% reported a skin infection by month 3 and 13% by month 6. Among index subjects, subsequent skin infection was associated with (P <0.05) Los Angeles site, diabetes, hospitalization in the prior 3 months, skin infection in the prior 12 months, cephalexin use in the prior 12 months, household fomite contamination with S. aureus, and household fomite contamination with MRSA; infection was inversely associated with contact sports participation. In the multivariate model, independent predictors of subsequent skin infection in index patients were hospitalization in the prior 3 months and household fomite contamination with MRSA; contact sports participation in the prior 3 months was inversely associated. Among household contacts, independent predictors of subsequent skin infection were Chicago site, antibiotic exposure in the prior 12 months, and skin infection in the prior 3 months.
Conclusion: In our longitudinal study of patients discharged after S. aureus infection, recurrence rates were very high. Patients were more likely to suffer recurrence if household fomites were MRSA contaminated. We found no pathogen or colonization-level factors associated with recurrent infection. S. aureus prevention efforts may need to focus on decontamination of household fomites to prevent recurrent infections.
M. Z. David, None
N. Ortiz, None
S. Boyle-Vavra, None
R. S. Daum, None