3 doctors weighed in:

Can you think of any reason why blood cultures would come back with negative results within 2 hours even though antibiotics not commenced until hours after the results have come back.

3 doctors weighed in
Dr. Gurmukh Singh
Pathology

In brief: Unclear question

If the blood culture results were reported within 2 hours, then it could not have bee culture, as that takes at least 24 hours, longer depending on the type of organism and microbial load.
It was probably some other test like CRP, not blood culture, that was reported within two hours of blood collection. It may help to talk to the pathologist in-charge of the laboratory.

In brief: Unclear question

If the blood culture results were reported within 2 hours, then it could not have bee culture, as that takes at least 24 hours, longer depending on the type of organism and microbial load.
It was probably some other test like CRP, not blood culture, that was reported within two hours of blood collection. It may help to talk to the pathologist in-charge of the laboratory.
Dr. Gurmukh Singh
Dr. Gurmukh Singh
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Dr. Richard Zimon
Internal Medicine

In brief: Yes

IT HAPPENS ALL THE TIME! Since many infectious agents circulate in the blood at certain INTERVALS between which no organism can be detected! That is why MULTIPLE Blood Cultures are taken instead of ONE SAMPLE! Hope this helps! Dr Z

In brief: Yes

IT HAPPENS ALL THE TIME! Since many infectious agents circulate in the blood at certain INTERVALS between which no organism can be detected! That is why MULTIPLE Blood Cultures are taken instead of ONE SAMPLE! Hope this helps! Dr Z
Dr. Richard Zimon
Dr. Richard Zimon
Thank
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