Objective: The majority of patients with anaerobic bloodstream
 infections (BSIs) do not receive appropriate empirical antimicrobial treatment
 as this infection remains unsuspected on clinical basis. This study determines
 the incidence rate, the prevalence and antibiotic susceptibility pattern of
 anaerobes causing BSIs in East Sussex Healthcare Trust, England.
 
 Methods: It
 is a retrospective study from July 2007 to July 2017. Demographic and
 laboratory data were collected on all microbiologically proven anaerobic BSIs. 
 
 Results:
 During the study period, 106,905 blood cultures were processed in the
 laboratory. A total of 324 anaerobic organisms were isolated from 312 blood
 cultures on 310 patients (167 males), representing a positivity rate of 0.30%
 of total blood cultures and 2.41% of total positive blood cultures (13,425).
 Approximately 76% (238 episodes) of anaerobic bacteremia occurred in >60
 years old (236) patients. The admitting services were: emergency department
 (ED) (42%), medical (25%), surgical (16%) critical care unit (7%), and
 hematology (5%). The most frequent isolates were Bacteroides spp. (42%),
 Clostridium spp. (24%), and
 Propionibacterium spp. (9%).  Polymicrobial bloodstream infections were
 recorded in 45 episodes. Amoxicillin/clavulanic acid, metronidazole, clindamycin
 remained most effective antibiotics against anaerobes with a sensitivity rate
 of 93%, 92%, and 81% respectively. Penicillin was least sensitive (43%) against
 anaerobes. 
 
 Conclusions: This study highlights a low rate of anaerobic
 bacteremia during 10 years with Bacteroides
 spp. as the predominant organism.
 This study also confirms that the empirical antibiotic therapy used in our
 hospital remains appropriate as more than 92% isolates were sensitive to
 amoxicillin/clavulanic acid and metronidazole. J Microbiol Infect Dis 2018; 8(4): 135-139