Abstract
This study aimed to investigate the clinical characteristics, distribution of different strains and risk factors of patients infected with Streptococcus anginosus group (SAG). In the population of 463 patients, the male-to-female ratio was 1.95:1, and the patient age ranged from 6 months to 103 years. There were 49 children (10.58%), 311 young and middle-aged adults (67.17%), and 103 elderly adults (22.25%). Approximately 45.4% had underlying conditions, which were mostly malignant tumors and diabetes. Of the 463 specimens, 254 were S. anginosus (54.86%), 173 were S. constellatus (37.37%), and 36 were S. intermedius (7.77%). According to the age distribution, the incidence peaked in the 35–54 year age group. Different sites of infection had statistically significant differences regarding the constituent ratios of these three species. Different age groups also exhibited statistically significant differences in constituent ratios of the pathogenic organisms, as well as organ infections. In our population, 269 were clinically cured, 184 reported satisfactory improvement, and 10 died. SAG, as an opportunistic pathogen, can induce pyogenic infections in patients of all ages and shows no significant gender predilection in any age group. The three pathogenic organisms had differences with respect to patient age and infections of body sites.
Highlights
Streptococcus anginosus group (SAG) is a group of gram-positive streptococci normally colonizing the upper respiratory, digestive and reproductive tracts and consists of three distinct species, S. anginosus, S. constellatus and S. intermedius
Infections of the oropharynx were associated with odynophagia, cervicodynia, and trachelophyma, leading to difficulties in swallowing and opening the mouth
In the 463 patients, the male-to-female ratio was 1.95:1, and the patient age ranged from 6 months to 103 years
Summary
Streptococcus anginosus group (SAG) is a group of gram-positive streptococci normally colonizing the upper respiratory, digestive and reproductive tracts and consists of three distinct species, S. anginosus, S. constellatus and S. intermedius. SAG is not recognized as a causative pathogen. With the presence of certain incentive factors, colonized SAG directly induces noninvasive infections and causes invasive infections after entering normal sterile sites in the body, including the blood and serosal cavity, which eventually affect the tissues and organs of various systems of the body. Infections caused by SAG should be considered in the clinical diagnosis and treatment of related infections. On this basis, a retrospective analysis of patients diagnosed with infections with SAG admitted by the general teaching hospitals of two regional medical centers between Jan. 2014 and Nov. 2019 was conducted, and the findings are reported below
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
