In this paper we present a prospective evaluation of 100 patients with Group A Streptococcal (GAS) bacteremia evaluated in our hospital over a 10-year period. Sixty-two patients were intravenous drug users (IVDU); all but 1 of these had an obvious cutaneous portal of entry related to the injection of illicit drugs. Twenty-seven patients had infectious metastasis, and the presence of septic pulmonary embolism was associated with suppurative phlebitis. Four of these patients had endocarditis. In the non-IVDU group, 24 patients had an underlying disease, and 12 were immunosuppressed. In 14 cases the infection was of hospital acquisition; in 35% infection was related to medical manipulations. Comparing the IVDU and non-IVDU groups, GAS bacteremia in IVDU patients is associated with a more benign outcome, a longer time of evolution before diagnosis, and a lower frequency of septic shock and mortality than in non-IVDU patients. Although in the univariate analysis GAS bacteremia was associated with several variables, in the multivariate analysis only the presence of shock and nosocomial acquisition of the infection were independently associated with a fatal outcome. Fifty-two patients were infected with human immunodeficiency virus (HIV); 5 of these were in the non-IVDU group. During the last 5 years of study, GAS bacteremia in our hospital was 39 times more frequent in HIV-infected patients than in patients without HIV. Nine patients presented clinical criteria corresponding to Streptococcal toxic shock syndrome (STSS), although its incidence was lower in the IVDU group. In the non-IVDU group, STSS was more frequent in patients with a necrotizing portal of entry, an age between 20 and 40 years, women, and when the origin of the infection was the skin or soft tissue. Six patients with STSS died, and death was associated with the presence of necrotizing lesions and lower counts of white cells, platelets, or hemoglobin.
