What is it?

A blood culture is done to check if bacteria or fungi are infecting your blood.

Usually, a blood infection occurs with other serious infections. These include infections in your lungs, kidneys, bowels, gallbladder, or heart valves.

You may also get a blood infection if your immune system is weak.

Why is this test done?

A blood culture is done to:

• Find a bacterial infection that has spread into the blood. These include meningitis and osteomyelitis. They also include pneumonia, kidney infections, and sepsis.
• Find a fungal infection in the blood. One common type is a yeast infection.
• Check for endocarditis. This is a bacterial infection on the heart valves.
• Find the best medicines to kill the bacteria or fungi.
• Find the cause of an unexplained fever, shock, or other very serious illness.

How do you prepare for the test?

• You do not need to do anything at home to prepare for the test.
• Tell your health professional if you took antibiotics recently.

How is the test done?

A health professional takes a sample of your blood.

Blood cultures are taken in special bottles using a needle to draw blood from two separate veins (usually one from each arm).

What happens after the test?

• If bacteria or yeast are found in the culture, your doctor may ask the lab to retest the blood several days later.
• You will probably be able to go home right away.
• You can go back to your usual activities right away.