Antimicrobial Resistance and Clinical Outcome of Bacteroides Bacteremia: Findings of a Multicenter Prospective Observational Trial

Abstract

There is debate regarding the correlation between in vitro susceptibility testing and clinical response to therapy for Bacteroides bacteremia. We conducted a prospective multicenter observational study of 128 patients with bacteroides bacteremia. Outcome was correlated with results of in vitro susceptibility testing of Bacteroides isolates recovered from blood and/or nonblood sites, determined with use of 3 end points: mortality at 30 days, clinical response (cure vs. failure), and microbiological response (eradication vs. persistence). The mortality rate among patients who received inactive therapy (45%) was higher than among patients who received active therapy (16%; P=.04). Clinical failure (82%) and microbiological persistence (42%) were higher for patients who received inactive therapy than for patients who received active therapy (22% and 12%, respectively; P=.0002 and.06, respectively). In vitro activity of agents directed at Bacteroides species reliably predicts outcome: the specificity was 97%, and positive predictive value was 82%. Antimicrobial susceptibility testing may be indicated for patients whose blood specimens yield Bacteroides species.

Bacteroides: the Good, the Bad, and the Nitty-Gritty

“…In one study of Bacteroides bacteremia, 44% of 128 patients had a surgical procedure within 4 weeks of the bacteremia and 30% had a malignancy (169). Twenty-eight percent of the patients had a polymicrobial bacteremia, and nine of the patients were infected with two different Bacteroides species.…”

Distribution, detection of enterotoxigenic strains and antimicrobial drug susceptibility patterns of Bacteroides fragilis group in diarrheic and non-diarrheic feces from Brazilian infants

“…Periodic monitoring in these organisms of the patterns of susceptibility to drugs has been recommended to enable the appropriate choice of antibiotic therapy to be made (17,24,36).…”

Enterotoxigenic Bacteroides fragilis: A potential instigator of colitis

“…7 Although humans are typically asymptomatically colonized, B. fragilis is identified as the leading anaerobe in bloodstream infections and intraabdominal abscesses. [8][9][10] A molecular subset of B. fragilis, termed enterotoxigenic B. fragilis (ETBF), secrete a 20-kDa proinflammatory zinc-dependent metalloprotease toxin, designated the B. fragilis toxin (BFT). ETBF are associated with diarrheal illnesses in animals, children, and adults.…”