Endocervical gram stain
Gram stain is a method of identifying bacteria using a special series of stains. In this test, a specimen from the cervix is stained and then examined under the microscope.
The gram stain method can be applied to almost any specimen and is one of the most commonly used techniques for the rapid diagnosis of bacterial infections.
A tissue sample is obtained from the lining of the cervical canal (the opening to the uterus). You lie on your back with your feet in stirrups (devices that support your feet and help keep you in proper position).
As in a regular pelvic examination, a speculum (an instrument used to stretch open the vagina in order to better examine some of the pelvic organs) will be inserted and opened slightly.
The cervix is cleaned so there is no mucus. A dry, sterile swab is then inserted and rotated within the cervical canal. It may be left in place for several seconds to absorb as many of the organisms as possible.
The swab is then removed and sent to a laboratory where it will be smeared on a slide. A series of stains called a gram stain is applied to the specimen. It is first stained with crystal violet stain, then iodine, then decolorized, then stained with safranin.
The stained smear is then examined under the microscope for the presence of bacteria. The color, size, and morphologic appearance (shape) of the cells help identify the infecting organism.
Do not douche for 24 hours before the procedure.
There may be minor discomfort during specimen collection. This procedure feels very much like a routine Pap smear.
The test is used to detect and identify abnormal bacteria in the area involving the cervix. If signs of an infection develop or a sexually transmitted disease (such as gonorrhea) is suspected, this test can help with confirmation and identification of an abnormal organism.
There are no abnormal bacteria present. Note that the normal cervix has "friendly" bacteria that should be seen by gram stain.
- Bacterial vaginosis
- Yeast infection
There is virtually no risk.
If gonorrhea or another sexually transmitted infection is present, it is very important that all sexual partners of the infected person receive treatment also, even if there are no symptoms.
Reviewed By: Kenneth Wener, M.D., Division of Infectious Diseases, Beth Israel Deaconess Medical Center, Boston, MA. Review provided by VeriMed Healthcare Network.