Test Overview
A urine culture is a test to find and
identify germs (usually bacteria) that may be causing a
. Urine in the bladder
normally is sterile—it does not contain any bacteria or other organisms (such
as
). But bacteria can enter the
and cause an infection.
A urine
sample is kept under conditions that allow bacteria and other organisms to
grow. If few organisms grow, the test is negative. If organisms
grow in numbers large enough to indicate an infection, the culture is
positive. The type of organisms causing the infection are
identified with a microscope or by chemical tests.
Urinary tract
infections are more common in women and girls than in men. This may be partly
because the female urethra is shorter and closer to the
, which allows bacteria from the intestines to
come into contact more easily with the urethra. (See a picture of the
.) Men also have an antibacterial substance in their
that reduces their risk.
If the urine culture is positive, other tests may be done to help choose
which antibiotic will do the best job treating the infection. This is called
sensitivity testing.