A culture is done to find out what kind of organism (usually a bacteria) is causing an illness or infection.

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

A culture is done by collecting a sample of body fluid or tissue and then adding it to a substance that helps promote the growth of bacteria or other disease-causing organisms. If there are bacteria (or other organisms) in the sample, they will grow in the culture. 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.