🧭 When to suspect

Trichomoniasis is a sexually transmitted infection caused by Trichomonas vaginalis, a flagellated protozoan parasite of the genital tract. In women it colonises the vagina, urethra and paraurethral glands (the urethra is involved in around 90% of infected women); in men it is almost always confined to the urethra. Transmission is almost exclusively sexual, so a diagnosis in one partner mandates assessment and treatment of the other.

Suspect it in any sexually active person with a vaginal or urethral discharge – classically frothy, yellow-green and offensive with vulval itch and soreness. The crucial caveat is that the infection is frequently silent: roughly 10–50% of women and 15–50% of men are asymptomatic, and men are most often identified through partner notification rather than presenting in their own right.

Typical features in women	Typical features in men
• Vaginal discharge – classically frothy, yellow-green and offensive, but this appearance occurs in only a minority.	• Urethral discharge and/or dysuria – usually scanty; the commonest symptomatic presentation.
• Vulval itching, soreness, dysuria and offensive odour.	• Urethral irritation or urinary frequency.
• Occasionally lower abdominal discomfort or vulval ulceration.	• Rarely balanoposthitis or features of prostatitis.
• 10–50% asymptomatic.	• 15–50% asymptomatic – usually a contact of an infected partner.

Source: BASHH 2021

🔒 Sign up free to read the full topic

You're viewing a free preview. Create a free account to unlock the rest.

Inside the full topic 🔒 History🔒 Red Flags🔒 Examination🔒 Patient Explanation🔒 Investigations🔒 Management🔒 Non-pharmacological Treatment🔒 Pharmacological Treatment🔒 Special Notes🔒 Referral Pathways🔒 Take Home Messages

Sample topics are open to everyone in the Free Sample Bundle.

Part of The Ocean Library, 450+ structured clinical topics mapped to the primary care curriculum. Companion audio in Echo · one-page summary in The Scope.