Clinical assessment of anaerobic isolates from blood cultures

doi:10.1016/0732-8893(93)90064-E

Diagnostic Microbiology and Infectious Disease

Volume 17, Issue 1, July 1993, Pages 19-22

https://doi.org/10.1016/0732-8893(93)90064-E Get rights and content

Abstract

Patients at two tertiary-care medical centers were evaluated to determine the clinical significance of anaerobic isolates from their blood specimens and to identify whether aerobic and/or anaerobic conditions were necessary for the detection of Streptococcus pneumoniae isolates. Significant anaerobes were isolated from only 0.1% and 0.4% of all blood cultures collected. The majority of patients with significant anaerobes had clinical conditions in which anaerobes are known to cause infections. Of the S. pneumoniae organisms, 83% were isolated only from the aerobic bottles of a blood culture set. These data lend support to the recommendations for the selective ordering of anaerobic blood cultures without compromising the isolation of S. pneumoniae.

References (9)

WJ Martin
Routine anaerobic blood cultures: reasons for continued use
Clin Microbiol Newslett
(1992)
SE Sharp
Routine anaerobic blood cultures: still appropriate today?
Clin Microbiol Newslett
(1991)
CW Dorsher et al.
Anaerobic bacteremia: decreasing rate over a 15 year period
Rev Infect Dis
(1991)
D Jungkind et al.
Clinical comparison of a new automated infrared blood culture system with the Bactec 460 system
J Clin Microbiol
(1986)

There are more references available in the full text version of this article.

Cited by (37)

The effect of intervention by an antimicrobial stewardship team on anaerobic bacteremia
2020, Anaerobe
Citation Excerpt :
Clinically significant anaerobic bacteremia was defined as ≥1 positive blood cultures with ≥1of the following criteria: white blood cell (WBC) count <4000 or >12,000/μL; body temperature >38 °C; or physical, pathological, or surgical evidence consistent with infection [20]. Considering its low pathogenicity and the infrequency of causing infections, Propionibacterium species were considered significant only when they were isolated in at least two sets of bottles drawn at the same time [21]. Cases with the same bacteria isolated multiple times within 14 days were defined as the same episode [22].
The effect of antimicrobial stewardship (AS) on anaerobic bacteremia is uncertain. This study aimed to assess the effect of interventions by the AS team (AST) on clinical and microbiological outcomes and antimicrobial use. An AS program was introduced at Osaka City University Hospital in January 2014; an interdisciplinary AST was established. We enrolled patients with anaerobic bacteremia between January 2009 and December 2018. Patients were classified into the pre-intervention group (from January 2009 to December 2013) and the post-intervention group (from January 2014 to December 2018). A significant decrease in definitive carbapenem use (P = 0.0242) and an increase in empiric tazobactam/piperacillin use (P = 0.0262) were observed in the post-intervention group. The de-escalation rate increased significantly from 9.38% to 32.7% (P = 0.0316) in the post-intervention group. The susceptibility of Bacteroides species and 30-day mortality did not worsen in the post-intervention group. These results showed that interventions by an AST can reduce carbapenem use and increase the de-escalation rate without worsening patient outcomes.
Comparative evaluation of paired blood culture (aerobic/aerobic) and single blood culture, along with clinical importance in catheter versus peripheral line at a tertiary care hospital
2012, Indian Journal of Medical Microbiology
Purpose: Paired blood culture (PBC) is uncommon practice in hospitals in India, leading to delayed and inadequate diagnosis. Also contamination remains a critical determinant in hampering the definitive diagnosis. Objectives: To establish the need of PBC over single blood culture (SBC) along with the degree of contamination, this comparative retrospective study was initiated. Materials and Methods: We processed 2553 PBC and 4350 SBC in BacT/ALERT 3D (bioMerieux) between October 2010 and June 2011. The positive cultures were identified in VITEK 2 Compact (bioMerieux). True positivity and contaminants were also analyzed in 486 samples received from catheter and peripheral line. Results: Out of 2553 PBC samples, positivity was seen in 350 (13.70%). In 4350 SBC samples, positivity was seen in 200 samples (4.59%). In PBC true pathogens were 267 (10.45%) and contaminants were 83 (3.25%), whereas in SBC 153 (3.51%) were true positives and contaminants were 47 (1.08%). Most of the blood cultures (99.27 %) grew within 72 h and 95.8% were isolated within 48 h. In 486 PBCs received from catheter/periphery (one each), catheter positivity was found in 85 (true positives were 48, false positives 37). In peripheral samples true positives were 50 and false positives were 8. Conclusion: Significantly higher positive rates were seen in PBCs compared with SBCs. Automated blood culture and identification methods significantly reduced the time required for processing of samples and also facilitated yield of diverse/rare organisms. Blood culture from catheter line had higher false positives than peripheral blood culture. Thus every positive result from a catheter must be correlated with clinical findings and requires further confirmation.
Blood cultures: Key elements for best practices and future directions
2010, Journal of Infection and Chemotherapy
Bloodstream infections (BSI) cause significant morbidity and mortality among populations worldwide. Blood cultures (BCs) are regarded as the “gold standard” for diagnosis of bacteremia and are among the most important functions of the clinical microbiology laboratory. Significant changes in the methods and techniques of obtaining BCs have occurred since the first inception of BCs into clinical practice. Aside from significant improvements of established, conventional technology, new assays for diagnosis of bacteremia and fungemia, particularly those involving molecular techniques, are now available. BCs must be collected under sterile conditions and guidelines for appropriate collection, processing, and results reporting of BCs have been established. This review provides comprehensive information on optimal BC practices for laboratories, utilizing traditional approaches and emerging technology. As laboratories and clinicians must appreciate the key factors affecting the use of these techniques, improved communication between laboratory personnel and clinicians regarding such elements as duration of incubation, workup of contaminants and critical action value reporting will greatly improve the diagnostic approach to BSI.
Clinic predictive model and validation of anaerobic bacteremias (including polymicrobial bacteremias)
2010, Enfermedades Infecciosas y Microbiologia Clinica
Las bacteriemias por microorganismos anaerobios son poco frecuentes, no existiendo consenso sobre su predictibilidad clínica y la utilidad rutinaria de los medios de cultivo para anaerobios. El objetivo del estudio es crear y validar un modelo predictivo de bacteriemia por anaerobios.
El modelo predictivo se realizó con 984 bacteriemias (45 anaerobios estrictos) durante 1985–86 y 1996–97. La validación durante 2005–06 con 320 bacteriemias.
Los factores predictores de bacteriemia por anaerobios calculados en el análisis multivariante para la creación de un modelo estratificado con puntuaciones de 0–13 puntos (p) fueron: origen desconocido (OR: 3,46; IC 95%: 1,13–10,54) 3 p; origen abdominal y cutáneo (OR: 14,85; IC 95%: 6,37–34,62) 6 p; hipotensión (OR: 1,99; IC 95%: 0,98–4,04) 2 p; ausencia de manipulaciones vasculares (OR: 2,62; IC 95%: 1,04–6,60) 2 p y edad >60 años (OR: 3,21; IC 95%: 1,19–8,67) 3 p. Con >7 p el modelo tiene S:77,8%, E:78,3%, VPP: 14,7% y un VPN del 98,6%, área bajo curva ROC=0,84 (EE=0,011). IC 95%: 0,82–0,86 con prevalencia de bacteriemia por anaerobios estimada 4,6%. La validación del modelo se realizó con 320 bacteremias (55 de ellas por anaerobios estrictos). El 83,6% (IC 95%: 71,19–92,23) de las bacteriemias por anaerobios tienen >7 p, y el 72,7% tienen 9 p o más. El 26,4% (IC 95%: 21,2–32,15) de las bacteriemias por aerobios y aerobios-anaerobios facultativos tienen >7 p, y solo el 11,7% tienen 9 p o más.Área bajo curva ROC=0,82 (EE=0,02). IC 95%: 0,78–0,86. Prevalencia estimada 2%.
El origen abdominal y cutáneo OR 14,85; origen desconocido OR 3,46; hipotensión OR 1,99; ausencia de manipulaciones vasculares OR 2,62 y edad >60 años OR 3,21 permiten crear un modelo clínico predictivo de bacteriemia por anaerobios con alta S y E. Por su baja prevalencia la importancia del modelo radica en su altísimo valor predictivo negativo.
Anaerobic bacteremias are uncommon. There is no agreement on their clinical predictability and the usefulness of anaerobic blood cultures. The objective of this study was to develop and validate a model for the prediction of anaerobic bacteremias.
The developing model was created with 984 bacteremias (45 anaerobic bacteremias) during 1985–1986 and 1996–1997. The validation model was made with 320 bacteremias during 2005–2006.
Independent multivariate predictors of true anaerobic bacteremia were used to develop a model stratifying patients with scores of 0 to 13 points(p), which were: unknown focus OR 3.46 (CI: 1.13–10.54) 3 p; abdominal and skin focus OR 14.85 (CI: 6.37–34.62) 6p; hypotension OR 1.99 (CI: 0.98–4.04) 2p; absence of vascular manipulations OR 2.62 (CI: 1.04–6.60) 2p and age over 60 years OR 3.21 (CI: 1.19–8.67) 3p. In the derivation sets group with more than 7p the model had Sensitivity: 77.8%, Specificity: 78.3%, PPV:14.7%, and a NPV of 98.6%. The area under curve was ROC=0.84 (SE=0.011), 95% CI: 0.82–0.86 with an anaerobic bacteremia prevalence of 4.6%. The validation set was studied analysing 320 bacteremias. Of these, 83.6% (95% CI: 71.19%–92.23%) of anaerobic bacteremias had more than 7 points, and 72.7% had more than 9 points. There was 26.4% (95% CI: 21.2%–32.15%) aerobic and facultative anaerobic bacteremias with more than 7 points, and only the 11.7% with 9 or more points. The area under the curve was, ROC=0.82 (SE=0.02), 95% CI:0.78–0.86, and estimated prevalence, 2%.
Abdominal and skin focus OR 14,85; unknown focus OR 3,46; hypotension OR 1,99; absence of vascular manipulations OR 2,62 and age over 60 years enable us to make a predictive clinical model of probability of anaerobic bacteremia with a high sensitivity and specificity. The model particularly has a significant predictive negative value due to the low prevalence of anaerobic bacteremia.
Anaerobic blood cultures: Useful in the ICU? [5]
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Use of simulated blood cultures for time to detection comparison between BacT/ALERT™ and BACTEC™ 9240 blood culture systems
2002, Diagnostic Microbiology and Infectious Disease
In order to avoid the influence of pre-analytical steps, the following study was performed by using sterile blood spiked with defined loads of microorganisms as inoculum. Time-to-Detection (TTD) was evaluated for the most frequently encountered bacteria and fungi in septicemia, comparing two commercially available blood culture systems, BACTEC™ 9240 (Becton Dickinson) and BacT/ALERT™ (Organon Teknika). A specific medium, Bactec Mycosis™ IC/F (Becton Dickinson), was compared with the Bactec Plus Aerobic (Becton Dickinson) and FAN Aerobic (Organon Teknika) media for recovery of fungi in general and in case of mixed bacterial/fungal septicemia. The results show that the BACTEC™ system detects nearly all enrolled microorganisms significantly faster than the BacT/ALERT™; the anaerobic vial contributes to the detection of anaerobes and facultative anaerobes and, in the case of BACTEC™, shortens TTD; the Bactec Mycosis™ IC/F bottle shortens TTD of fungi.

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View full text

Clinical assessment of anaerobic isolates from blood cultures

Abstract

Clin Microbiol Newslett

Clin Microbiol Newslett

Anaerobic bacteremia: decreasing rate over a 15 year period

Rev Infect Dis

Clinical comparison of a new automated infrared blood culture system with the Bactec 460 system

J Clin Microbiol