Music It’s a typical day. A patient has noticed some itching, or maybe an unpleasant vaginal odor. During her exam, the ian will check vaginal pH, examine any discharge that’s present, and collect a sample. Then, it’s on to the microscope. music This is where you’ll gather more specific information about what’s causing those vaginal symptoms. We’ll show you how to prepare and examine vaginal wet preps and how to do a whiff test. The results, combined with the patient’s vaginal pH test, will aid in the diagnosis.
Under the microscope, you’ll be looking for trichomonads, yeast, and the clue cells associated with bacterial vaginosis. We’ll show you how to recognize them. music First, the microscope itself: This is a compound light microscope. It has several objective lenses on a rotating mount. For our purpose, one of these has to be a 10x low power objective, and one has to be a 40x for greater magnification. This flat part, under the objectives, is the stage. Under the stage is the condenser. Below that, at the base of the microscope, is the light source. There are two knobs that control focus; one for coarse adjustment and one for.
Fine adjustment. And these are the oculars, or eyepieces. We’ll come back to the microscope in a minute, but first, let’s look at how to prepare wet mount slides. The complete vaginal wet mount involves both a saline prep and a potassium hydroxide, or KOH, prep. When the vaginal sample was collected, the swab was placed in a test tube with approximately half a milliliter of saline. So, for the saline prep, you only have to take a drop of the suspension and place it on a slide. Add a coverslip, being careful to avoid trapping air bubbles. Your saline slide is ready. Place a second drop of the vaginal sample on another slide and add one drop of 10 percent KOH. Sniff the preparation immediately, using.
Your hand to waft any odor toward your nose. This is the whiff test. Note if there’s a fishy or amine odor. Then add a coverslip, avoiding air bubbles. Keep in mind that you must work quickly to prepare and examine the wet mounts. That’s because trichomonads may lose their characteristic motility within 15 to 20 minutes. Before we move on now, though, let’s look at the cast of characters you may discover. These are normal squamous epithelial cells found in the vagina. They’re large, flat cells with a small nucleus and a large area of cytoplasm. Note that there is some granularity in the cytoplasm.
Polymorphonuclear leukocytes are known as Polys, or PMNs. They may also be called white blood cells, or WBCs. These are small round cells. Several lobes of the nucleus are visible within the surrounding cell cytoplasm. Finding many PMNs may indicate infection. Trichomonads are pearshaped protozoa which move by means of flagella. Trichomonads are similar in size to PMNs and are identified by their characteristic jerking movement. The actual flagella may be too thin and too rapidlymoving to be seen. A clue cell is a squamous epithelial cell coated with enough small bacteria that at least 75 percent of the cell’s border is obliterated. It may look as if someone has spread glue.
Over the cell and pressed it in sand. Clue cells are associated with bacterial vaginosis, a condition in which the normal microbial flora of the vagina is disrupted. Yeast may be found in two forms. Pseudohyphae are the long, tubular, branching forms. Budding yeast are paired yeast cells that resemble a shoe print. The larger part is the sole and the smaller bud is the heel of the shoe. The saline prep will allow you to see epithelial cells, PMNs, trichomonads, and clue cells. You can also see yeast in saline, but sometimes it’s hidden by epithelial cells or by PMNs. Red blood cells, sperm, and bacteria can also be seen.
The KOH prep will only help you detect yeast. Epithelial cells, PMNs, trichomonads, and clue cells will be broken apart, or lysed. Lysing the other cells makes it much easier to see yeast. A positive whiff test, defined by a fishy odor, may indicate either trichomoniasis or bacterial vaginosis. KOH volatizes amines which are associated with both these conditions. When that happens, the fishy odor is easier to detect. Now that you know what to look for, let’s get back to the microscope. Put your slide on the stage, and rotate the 10x objective into place. Turn on the light. Bring the sample into focus using the coarse adjustment knob. Next, you’ll need to find the best contrast,.