Blood cultures
Culture for a range of bacterial and fungal pathogens.
Other Comments:
Collection containers : Paired blood culture set (adults), single paediatric bottle (neonates and children)
BacT/ALERT FA PLUS aerobic - Optimal 8-10ml. If the volume of blood is inadequate for two bottles, the aerobic bottle should be inoculated first and then the rest inoculated to an anaerobic bottle. This bottle recovers wide range of aerobic organisms and contains resin to neutralise antibiotics. Does not recover anaerobic organisms.
BacT/ALERT FN PLUS Anaerobic - Optimal 8-10ml. Recovers facultative and anaerobic organisms.
BacT/ALERT PF PLUS Paediatric - Up to 4ml Optimised for use with paediatrics. May be used for adults if only a small volume of blood can be obtained. Does not reliably recover anaerobic organisms.
Special instructions - Relevant clinical data and details of recent or current antimicrobial treatment should be provided:
NB PLEASE STATE IF THERE IS A HISTORY OF IV DRUG USE, CONTACT WITH SEWAGE, LIVESTOCK, EXOTIC OR IMPORTED ANIMALS, RECENT OR PROLONGED FOREIGN TRAVEL.
If infection with HACEK or other unusual organisms suspected, contact consultant microbiologist to discuss as prolonged incubation may be required
(HACEK organisms: Haemophilus species Aggregatibacter Cardiobacterium Eikenella Kingella)
Please refer to the infection prevention pages of the UHNM website. Sampling of blood should be performed according to Department of Health guidelines Taking Blood Cultures – A Summary of Best Practice. If blood for other tests is to be taken at the same venepuncture, the blood cultures should be inoculated first to avoid contamination. It is preferable to take blood for culture separately.
If it is clinically indicated, multiple blood culture sets may be collected. If this is done the following guidelines should be followed if possible:
• Collect sets from different venepuncture sites
• Collect sets at a different time Specimen
Transport: Transport to laboratory immediately. Do not refrigerate.
Department: Microbiology, Virology and Molecular Microbiology
Requirement:
Volume of Blood:
Adults - optimal volume 8-10ml (do not overfill)
Paediatrics/neonates up to 4ml in paediatric blood culture bottle
False negatives may occur if inadequate blood culture volumes are submitted.
Do not overfill bottles as this does not improve recovery rate.
Turnaround Time:
Positive bottles with organisms seen in Gram film are telephoned to the ward by authorised laboratory staff and the report will be posted electronically. Outside normal working hours Gram stain results are posted electronically but may not be phoned if the isolate is unlikely to be significant.
When blood culture bottles are loaded onto the system, a “Negative to Date” statement is released electronically.
Interim result negative result will be reported after 48 hours -this will remain unchanged until the blood culture is finally reported negative after 5 days OR the bottles become positive.
For neonatal unit only – interim negative results are reported at 36 hours. A final report is issued after 5 days.
Please note that results cannot be posted electronically if patient identifier information is not complete and accurate.