The test is sensitive but not specific, since this pH can be found in one third of those with normal vaginal flora or candidiasis. In the presence of trichomoniasis or bacterial vaginosis, polyamines, a product of anaerobic metabolism, results in a fishy smell. The wet prep is prepared by mixing vaginal secretions with normal saline. Due to the low number of organisms, trichomonads may not be detected in asymptomatic or chronically infected women. The trichomonad is pear shaped with undulating flagella that provide active motility.
Motility is lost if the specimen dries.
Sperm also may be motile, but the head is far smaller and the tails much longer than those of trichomonads. A large number of WBCs also are observed in symptomatic women. The epithelial cells appear normal, and coccobacilli are the predominant bacterial flora. Endocervical specimens cannot be used for wet mount diagnosis due to the small numbers of organisms, but the specimens may be used for culture. In men, a specimen obtained from the anterior urethra by a platinum loop may demonstrate organisms.