Incidence of and risk factors for clinically significant methicillin-resistant Staphylococcus aureus infection in a cohort of HIV-infected adults

J Acquir Immune Defic Syndr. 2005 Oct 1;40(2):155-60. doi: 10.1097/01.qai.0000179464.40948.b9.

Abstract

Objectives: Outbreaks of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) have been noted in multiple sites in the United States. This study's purpose was to estimate trends in the incidence of and risk factors for clinically significant MRSA (CS-MRSA) infection in a cohort of HIV-infected adults.

Design: A retrospective clinic-based cohort (January 1, 2000-December 31, 2003) study.

Methods: We ascertained all initial episodes of CS-MRSA and categorized them by primary site. Incidence rates were estimated by half year. Risk factors for CA-MRSA infection were identified using Cox modeling.

Results: Of 126 potential events, 94 were CS. Their primary sources were 83% skin or soft tissue, 10% blood, 6% respiratory, and 1.0% other sites. Among these, 60% were CA and 40% were nosocomial. Of antibiotics tested, only cotrimoxazole resistance was associated with nosocomial acquisition. The 3455 patients contributed 7003 person-years at risk. The incidence of CS-MRSA infection increased 6.2-fold from the first to the last half year. In multivariate analysis, independent predictors of CA-MRSA infection included HIV transmission by men who have sex with men or by injection drug use, CD4 count <50 cells/muL, log10 HIV plasma viral load, and absence of cotrimoxazole prophylaxis.

Conclusions: The incidence of initial CS-MRSA events increased more than 6-fold in a 4-year period. The associations between CA-MRSA infection and HIV severity indicators merit examination in other cohorts.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Cohort Studies
  • Female
  • HIV Infections / complications*
  • Humans
  • Incidence
  • Male
  • Methicillin Resistance*
  • Middle Aged
  • Retrospective Studies
  • Risk Factors
  • Staphylococcal Infections / complications
  • Staphylococcal Infections / epidemiology*
  • Staphylococcus aureus / isolation & purification*