Comparative evaluation of the role of single and multiple blood specimens in the outcome of blood cultures using BacT/ALERT 3D (automated) blood culture system in a tertiary care hospital.
BACKGROUND
Bloodstream infection (BSI) is a leading cause of mortality in critically ill patients. The mortality directly attributable to BSI has been estimated to be around 16% and 40% in general hospital population and Intensive Care Unit (ICU) population, respectively. The detection rate of these infections increases with the number of blood samples obtained for culture. The newer continuous monitoring automated blood culture systems with enhanced culture media show increased yield and sensitivity. Hence, we aimed at studying the role of single and multiple blood specimens from different sites at the same time in the outcome of automated blood culture system.


RESULTS
A total of 1054 blood culture sets were analyzed over 1 year, the sensitivity of one, two, and three samples in a set was found to be 85.67%, 96.59%, and 100%, respectively, which showed a statistically significant difference (P < 0.0001). Similar findings were seen in few more studies, however, among individual organisms in contrast to other studies, the isolation rates of Gram-positive bacteria were less than that of Gram-negative Bacilli with one (or first) sample in a blood culture set. In our study, despite using BacT/ALERT three-dimensional continuous culture monitoring system with FAN plus culture bottles, 15% of positive cultures would have been missed if only a single sample was collected in a blood culture set.


CONCLUSIONS
The variables like the volume of blood and number of samples collected from different sites still play a major role in the outcome of these automated blood culture systems.
Department of Microbiology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India.
D
D
Elantamilan
Department of Microbiology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India.
Valarie Wihiwot
VW
Lyngdoh
Department of Microbiology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India.
Annie B
AB
Khyriem
Department of Microbiology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India.
Jyotismita
J
Rajbongshi
Department of Microbiology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India.
Ishani
I
Bora
Department of Microbiology, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India.
Surbala Thingujam
ST
Devi
Department of Anaesthesiology and Critical Care, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India.
Prithwis
P
Bhattacharyya
Department of Paediatrics, North Eastern Indira Gandhi Regional Institute of Health and Medical Sciences, Shillong, Meghalaya, India.
Himesh
H
Barman
BacT/ALERT 3D; FA plus; bacteremia; blood stream infections; number of samples
J Clin Microbiol. 2014 Mar;52(3):839-43
24371240
Clin Infect Dis. 2002 Oct 1;35(7):842-50
12228821
Rev Infect Dis. 1983 Jan-Feb;5(1):54-70
6828812
Mayo Clin Proc. 1975 Feb;50(2):91-8
1090789
Clin Infect Dis. 2004 Jun 15;38(12):1724-30
15227618
J Clin Microbiol. 2007 Nov;45(11):3546-8
17881544