A culture is a test to find germs (such as bacteria or a fungus) that can cause an infection.

A sensitivity test checks to see what kind of medicine, such as an antibiotic, will work best to treat the illness or infection.

For a culture, a sample of body fluid or tissue is added to a substance that promotes the growth of germs. If no germs grow, the culture is negative. If germs that can cause infection grow, the culture is positive. The type of germ may be identified using a microscope or chemical tests. Bacteria usually grow quickly in a culture (2 days), while other types of organisms, such as a fungus, can take longer.

A culture and sensitivity test may be done on many different body fluids, such as urine, mucus, blood, pus, saliva, breast milk, spinal fluid, or discharge from the vagina or penis.