Group B streptococcal bacteremia in non-pregnant adults.

BACKGROUND AND PURPOSE: An increasing incidence of group B streptococcus (GBS) infection in non-pregnant adults has been noted in recent years. To understand the incidence, clinical characteristics, and outcome of GBS bacteremia in non-pregnant adults, we conducted a retrospective study at a tertiary teaching hospital in Taiwan.

METHODS: This retrospective analysis included 94 non-pregnant adults (age >/=18 years) with GBS bacteremia hospitalized between January 2001 and December 2003.

RESULTS: The incidence of GBS bacteremia increased from 0.16 cases/1000 admissions in 2001 to 0.30 cases/1000 admissions in 2003 (p=0.017, chi-squared test for trend). The mean age of patients was 64.7 +/- 1.39 years. At least 1 underlying systemic disease was found in 81% of patients, with the most frequent being malignancy (43.6%), diabetes mellitus (42.6%), and liver cirrhosis (16%). The 2 major clinical syndromes were primary bacteremia (34%) and soft tissue infection (31.9%). The overall mortality rate was 20.2%. Staphylococcus aureus and Klebsiella pneumoniae were the 2 most common concurrently isolated bloodstream pathogens. Polymicrobial bacteremia, thrombocytopenia, and shock were independent risk factors for mortality in GBS bacteremia.

CONCLUSIONS: The increasing incidence of GBS bacteremia is noteworthy, especially among patients with invasive infections. These infections are also responsible for substantial mortality in elderly patients with underlying diseases. Susceptibility testing indicated that penicillin G remains the drug of choice for GBS bacteremia.