Blood culture
blood culture · blood culture test · bacteria in blood test · sepsis test
Blood is taken from a vein into special bottles. The lab watches whether germs grow in it.
For a high fever and a possible infection in the blood. It is usually done in hospital.
⏱ Duration: the draw takes 5 to 10 minutes; a first answer usually comes in 1 to 3 days, the final one in up to 5 to 7 days
Be sure to tell your doctor
How to prepare
- Antibiotics. It is best to take the sample before the first antibiotic dose. But treatment is not delayed. The doctor decides.
- Food. No special prep.
- Timing. Blood is often taken at the peak of a fever or during chills.
What to bring
- Your referral, if done as an outpatient
- Your ID
How it goes
- The skin on your arm is cleaned with antiseptic for a long time and very carefully
- A band is tightened above your elbow
- Blood is drawn into 2 bottles, sometimes from both arms
- The needle comes out, and a cotton pad is pressed on
- The bottles go to the lab right away
What you'll feel
- A quick prick, like a pinch
- From both arms means two pricks
Afterwards
- Press the cotton pad for 3 to 5 minutes
- A first answer usually comes in 1 to 3 days, the full one in up to a week
- If a germ grows, the lab checks which antibiotics work on it
Contact a doctor straight away if
- Chills, a fever over 39°C (102°F), confusion, or strong weakness: call emergency services
Common questions
Why take blood from both arms?
It makes it easier to tell a real infection from a stray germ from the skin.
Why wait a week?
Some germs grow slowly. While waiting, treatment has usually already started.