Association between Staphylococcus aureus nasopharyngeal colonization and septicemia in patients infected with the human immunodeficiency virus.

In an attempt to identify risk factors for Staphylococcus aureus septicemia, 136 consecutive HIV-infected patients were investigated for the presence of nasopharyngeal colonization with Staphylococcus aureus and subsequent Staphylococcus aureus infection. Sixty of 136 (44.1%) HIV-infected patients had staphylococci which were detected in the nasopharynx on initial culture compared to 12 of 39 (30.8%) patients with chronic diseases and 11 of 47 (23.4%) healthy hospital staff. Another 12 HIV-infected subjects proved to be Staphylococcus aureus carriers on follow-up cultures. Patients with full-blown AIDS had a higher carriage rate compared to subjects who were only HIV-positive (p < 0.05), indicating that Staphylococcus aureus colonized patients were more severely ill. Eight patients with Staphylococcus aureus septicemia were observed, all of whom were carriers; no septicemia occurred in the non-colonized patients (p < 0.01). Colonized patients with neutropenia (< 1000/microliters) were significantly more likely to develop septicemia (p < 0.01). Nasopharyngeal colonization with Staphylococcus aureus and the presence of an indwelling catheter were established to be factors that help identify patients at risk of acquiring subsequent Staphylococcus aureus infection.