Streptococcus Anginosus Group Bacterial Infections

Abstract Background The Streptococcus anginosus group (SAG) cause a variety of infections in adults. To better understand the burden of SAG infections and their associated morbidity and mortality, we conducted a retrospective analysis of these infections in adults at a tertiary care center. Methods A retrospective review of all cultures positive for SAG in adults and a corresponding review of their medical records was conducted at a tertiary care facility in Central New York. Patients with these cultures during the period of January 2007 to December 2011 were included. Demographic data, area of residence, clinical features and underlying illnesses, site of infection, length of hospital stay, antibiotic susceptibility and antibiotic therapy were recorded and analyzed. Results There were 332 SAG cases; the majority of patients were male (59%), mean age of 47 years, and 84% lived in urban areas. Overall mortality was 3% with underlying conditions common such as diabetes (25%), hypertension (31%) and immunodeficiency (22%). The majority of infections were skin and soft tissue (72%) and polymicrobial (70%) with gram negative anaerobes and Enterobacteriaceae commonly isolated with SAG. Conclusions We present the largest study thus far reviewing the clinical presentation, management and outcome of infections due to the Streptococcus anginosus group of organisms. Notable findings from our study are the low mortality associated with SAG infection, and the propensity to present as a skin, soft tissue and polymicrobial infection. Our findings will assist clinicians in managing patients with SAG infections and recognizing that strep anginosus may be one of several organisms responsible for infection.