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Blood Culture


This educational webpage is based on the Blood Culture Educational Booklet that you can access HERE.

The presence of bacteria in the blood. It may be transient, intermittent or continuous.

Blood specimen submitted for culture of microorganisms. It enables the recovery of potential pathogens from patients suspected of having bacteremia or fungemia.

A group of temporally related blood cultures that are collected to determine whether a patient has bacteremia or fungemia.

The combination of blood culture bottles (one aerobic and one anaerobic) into which a single blood collection is inoculated.

An infection associated with bacteremia or fungemia.

A microorganism recovered from a blood culture that was introduced during specimen collection or processing and is not considered responsible for BSI (i.e. the isolates were not present in the patient’s blood when the blood was sampled for culture).

Presence of microorganisms in the bottle that entered during sampling but were not actually circulating in the patient’s bloodstream.

The presence of fungi in the blood.


Life-threatening organ dysfunction caused by a dysregulated host response to infection characterized by fever, chills, malaise, tachycardia, etc. when circulating bacteria multiply at a rate that exceeds removal by phagocytosis.5

An episode of sepsis or septic shock for which a blood culture or blood culture series is drawn.

A subset of sepsis in which underlying circulatory and cellular metabolism abnormalities are profound enough to substantially increase mortality.5

Source: CLSI. Principles and Procedures for Blood Cultures. 2nd ed. CLSI guideline M47. Clinical and Laboratory Standards Institute; 2022 unless otherwise specified.

The content on this website and associated materials do not constitute medical advice and should not be considered a substitute for the individual professional judgement of any physician or other health care practitioner regarding the appropriate course of action for a particular patient. All recommendations should be independently reviewed with appropriate medical staff in light of the needs of any particular institution and its patients. bioMérieux makes no guarantee or representation regarding the accuracy, completeness, or usefulness of this information for any particular purpose, including but not limited to any cost savings.