Trichomonas Vaginalis

Here's an interesing flagellate parasite I have learnt about over the course of my GU Medicine placement. It causes Trichomoniasis, most commonly found in women engaging in sexual activity, and can live in the vagina, urethra and bladder. Men can also have TV, but the parasite is very rarely seen in them.

Here's the delightful parasite itself:

Nice, eh? When looking at it under a microscope you can see the thread-like flagellum moving around enabling it to "swim". I guess it's almost like having nits, but in a different area. Not nice to imagine something moving around in your body, is it?!

Patients with TV present with the following symptoms (if any):

• vaginal discharge (thin, often yellow/frothy and offensive)
  
• vulvovaginal pain/irritation


• dysuria


• dyspareunia


• vulval, vaginal and cervical mucosa is red
  

Fortunately, TV is fairly straightforward to get rid of: Metronidazole 400mg bd for five days. It's important that the patient doesn't drink alcohol for the duration of the course (and 48 hours after completing the course) as this can cause sickness. Also, the patient must not have sexual intercourse until a satisfactory follow-up appointment has been carried out. Any partners should also be treated, including men as they can pass the parasite on to other women.

We diagnose TV by looking for the parasite on a wet vaginal slide under a microscope. It tends to look something like this:

Among the epithelial cells, polys and/or "clue" cells, TV can be seen due to it's flagellum flapping about. We also look for TV on dry vaginal slides, by gram staining them (to be written about in a future post):

So there we have it. A short guide to trichomonias vaginalis.