Epidemiology and Antimicrobial Susceptibility of Anaerobic Bloodstream Infections: A 10 Years Study

Year 2018, Volume: 08 Issue: 04, 135 - 139, 15.12.2018

Nadeem Sajjad Raja

https://doi.org/10.5799/jmid.493845

Cited By: 1

Abstract

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

Keywords

Anaerobes, antibiotics, bloodstream infections, susceptibility

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