Which test is NOT typically ordered for diagnosing trichomonas vaginitis?

The choice of a CT scan of the abdomen as an answer is appropriate because it is not a standard diagnostic tool for trichomonas vaginitis. Trichomonas vaginitis is diagnosed through direct examination methods and specific tests related to the urogenital tract, rather than imaging studies like a CT scan.

Wet mount microscopy is commonly ordered for diagnosing this condition because it allows for direct visualization of the trichomonas organisms in vaginal secretions. Vaginal pH testing can also be helpful, as an elevated pH is often seen in cases of trichomonas vaginitis. The amine "whiff" test, which assesses the release of amines with a particular odor upon mixing vaginal secretions with KOH, can sometimes help differentiate trichomonas vaginitis from bacterial vaginosis.

Thus, the CT scan is not relevant in this context, as it is used for assessing other abdominal or pelvic issues rather than for evaluating vaginitis or other infections directly.