Blood culture

A blood sample is needed . The site where blood will be drawn is first cleaned with an antiseptic such as chlorhexidine. This reduces the chance of an organism from the skin getting into (contaminating) the blood sample and causing a false-positive result (see below). The sample is sent to a laboratory. There, it is…

There is no special preparation.

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a slight bruise. This soon goes away.

Your health care provider may order this test if you have symptoms of a serious infection, also known as sepsis . Symptoms of sepsis can include high fever, chills, rapid breathing and heart rate, confusion, and low blood pressure. The blood culture helps identify the type of bacteria causing the infection. This helps…

A normal value means that no bacteria or other germs were seen in your blood sample.

An abnormal (positive) result means that germs were identified in your blood. If the germs are bacteria, the medical term for this is bacteremia. This can cause sepsis. Sepsis is a medical emergency and you will be admitted to a hospital for treatment. Other types of germs, such as a fungus or a virus, may also be…

There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others. Other risks associated with having blood drawn are slight, but may include: Excessive…

Plourde AR, Beavis KG. Specimen collection and handling for diagnosis of infectious diseases. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods . 24th ed. Philadelphia, PA: Elsevier; 2022:chap 66. Patel R. The clinician and the microbiology laboratory: test ordering,…