Nasal carriage of and infection with Staphylococcus aureus in HIV-infected patients

Ann Intern Med. 1999 Feb 2;130(3):221-5. doi: 10.7326/0003-4819-130-3-199902020-00026.


Background: Staphylococcus aureus is a common cause of serious infection in patients infected with HIV.

Objectives: To evaluate risk factors for and quantitative effect of S. aureus infection in HIV-infected patients, with special attention to nasal carriage.

Design: Prospective, multihospital cohort study.

Setting: Three tertiary care Veterans Affairs Medical Centers.

Participants: 231 ambulatory HIV-infected patients.

Results: Thirty-four percent of patients were nasal carriers of S. aureus. Of these patients, 38% were persistent carriers and 62% were intermittent carriers. Twenty-one episodes of infection occurred in 13 patients: Ten were bacteremias (including 2 cases of endocarditis), 1 was pneumonia, and 10 were cutaneous or subcutaneous infections. Seventeen (85%) of these episodes occurred in patients with CD4 counts less than 100 cells/mm3. Recurrent infections occurred in 3 of 7 patients who survived an initial S. aureus infection. The mortality rate was higher among patients with S. aureus infection than among those without infection (P = 0.03). Factors significantly associated with S. aureus infection were nasal carriage, presence of a vascular catheter, low CD4 count, and neutropenia. Molecular strain typing indicated that for 6 of 7 infected patients, the strain of S. aureus isolated from the infected sites was the same as that previously cultured from the nares.

Conclusion: Nasal carriage is an important risk factor for S. aureus infection in HIV-infected patients. Controlled studies are indicated to determine whether eradication of nasal carriage in a selected subset of patients (for example, those with a low CD4 cell count) might prevent invasive S. aureus infection in patients with HIV infection.

MeSH terms

  • AIDS-Related Opportunistic Infections / epidemiology*
  • AIDS-Related Opportunistic Infections / mortality
  • Acquired Immunodeficiency Syndrome / immunology
  • Analysis of Variance
  • CD4 Lymphocyte Count
  • Humans
  • Neutropenia / complications
  • Nose / microbiology*
  • Prospective Studies
  • Risk Factors
  • Staphylococcal Infections / epidemiology*
  • Staphylococcal Infections / immunology
  • Staphylococcal Infections / mortality
  • Staphylococcus aureus / classification
  • Staphylococcus aureus / isolation & purification*