title: Clinical and microbiological outcomes in patients with Streptococcus anginosus group bacteraemia identified through use of a rapid microarray assay.
abstract: Limited data exist evaluating outcomes in patients with serious Streptococcus anginosus group infections, particularly bacteraemia. A retrospective, single-centre cohort study was conducted to characterize potential risk factors along with clinical and microbiological outcomes in patients with S. anginosus group bacteraemia (SAGB). Adult inpatients with SAGB identified using the Verigene Gram-positive blood culture assay between March 2013 and April 2014 were included. Patients aged ≤ 18 or >89 years, those with SAGB identified at an outside facility and those who were incarcerated were excluded. Differences between groups were explored using a Wilcoxon rank-sum test, χ2 test, Student's t-test or Fisher's exact test as appropriate and a two-tailed P value of ≤ 0.05 was considered statistically significant. The 34 patients who met the inclusion criteria were 57 ± 14 (mean ± SD) years old and had a median Charlson co-morbidity index of 4 [interquartile range (IQR) 1-6] and 10 (29%) were immunosuppressed at baseline. Almost half (47%) had received antibiotics in the previous 90 days. Twelve (35%) patients had gastrointestinal malignancies and the commonest source of bacteraemia was the gastrointestinal tract (53%). The primary species responsible for SAGB was S. anginosus (68%), and overall susceptibility to penicillin was 91%. Patients were most often treated with a β-lactam/β-lactamase inhibitor combination (36%) for a duration of 8 (IQR 4-13) days. Length of stay (LOS) and infection-related LOS were 10 (IQR 5-17) and 9 (IQR 4-12) days, respectively. Twenty [59%] patients achieved a clinical cure, while 29 (85%) achieved a microbiological cure. Four (12%) patients died and one patient was readmitted within 30  days. In the largest cohort of patients with SAGB to date, gastrointestinal malignancies may have been an important risk factor for SAGB, while rapid identification via a microarray assay likely contributed to improved disease recognition and timely pharmacological and non-pharmacological therapy.
authors.affiliation: Department of Pharmacy, The Ohio State University Wexner Medical Center, Columbus, OH, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Wenzler
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, The Ohio State University Wexner Medical Center, Columbus, OH, USA.
authors.forename: Vidhya
authors.initials: V
authors.lastname: Chandrasekaran
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, The Ohio State University Wexner Medical Center, Columbus, OH, USA.
authors.forename: Patricia
authors.initials: P
authors.lastname: Salvador
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, The Ohio State University Wexner Medical Center, Columbus, OH, USA.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Anwar
authors.affiliation: Department of Pathology, The Ohio State University Wexner Medical Center, Columbus, OH, USA.
authors.forename: Preeti
authors.initials: P
authors.lastname: Pancholi
authors.affiliation: Department of Internal Medicine, Division of Infectious Diseases, The Ohio State University Wexner Medical Center, Columbus, OH, USA.
authors.forename: Bradford S
authors.initials: BS
authors.lastname: McGwire
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D016470:Bacteremia / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D046228:Microarray Analysis / Q000379:methods*; D008875:Middle Aged; D012189:Retrospective Studies; D013290:Streptococcal Infections / Q000382:microbiology*; D034366:Streptococcus anginosus / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents