The rectal swab is a diagnostic test aimed at collecting fecal material, to be analyzed in the laboratory for the possible isolation of the microorganisms responsible for intestinal diseases (for example the cholera bacterium, salmonella, shigella, campylobacter etc.). During pregnancy, the rectal swab is indicated for the research of Streptococcus agalactiae (or group B streptococcus).
The examination uses a sterile swab, similar to a cotton swab, moistened with the transport medium. This swollen stick is inserted into the rectum, through the anus, at a depth of about 2-4 centimeters, then rubbed to make the fecal material adhere. The swab is kept in the rectal ampulla for 30 seconds, continuing to move it and rotate it against the walls of the intestine; after which it is extracted and immersed in the test tube containing the transport medium. Before storing it, make sure that the tip of the swab shows significant traces of fecal material.
If possible, stool collection is generally preferable to rectal swab use.
