Trichomonas vaginalis

Question 1

Definition

Answer 1

STI urogenital infection with the protozoan parasite = Trichomonas vaginalis
Can occur in both males and females

Question 2

Transmission

Answer 2

• Almost exclusively through sexual intercourse
  -Vertical transmission
• • Not believed to be transmitted by kissing, oral or anal sex, sharing utensils or toilet seat *

Question 3

Epidemiology and risk factors

Answer 3

• Female
• Race: Black Carribean women
• <25 or less
• Unprotected sexual intercourse
• Multiple sexual partners
• Previous history of STIs
• Sharing unwashed sex toys

Question 4

Pathophysiology

Answer 4

• Pear shaped parasite that moves up the urethra or vaginal tract using flagella
• Flagella latch onto urethral or vaginal cells, stressing the host cell membrane and causing lysis
• Subsequent host inflammatory response = irritation e.g.
• Urethritis (causing dysuria)
• Vaginitis (Causing discharge)
• Cervicitis (causing dyspareunia)

Question 5

Signs

Answer 5

• Yellow-green discharge coating vaginal walls, particularly the posterior fornix
• Malodorous discharge
• Erythematous punctate “strawberry” cervix pathognomonic but only seen in 2% of cases

Question 6

Symptoms

Answer 6

• 10-15% ASx
• Frothy, yellow-green vaginal discharge, often foul smelling e.g. ‘fishy’
• Thin, white discharge from the penis
• Dysuria
• Vulval itching and swelling
• Dyspareunia

Question 7

Diagnosis

Answer 7

All patients should be referred to a genito-urinary medicine (GUM) clinic
- Vaginal pH test: alkaline pH >4.5 +ve (normal = 3.5-4.5)
- GOLD STANDARD: High vaginal swab of discharge from posterior fornix
- Urethral swab +/or first-void urine sample: FIRST LINE MALES for MC+S

Question 8

Treatment

Answer 8

FIRST LINE ABx:
- Oral metronidazole: for men and women = 5-7 day course of 400-500mg
= safe for preggos

Oral tinidazole: for men and non-pregnant women, a single 2g dose

Question 9

Prevention

Answer 9

• Treat sexual partners: treat current partner(s) simultaneously + any partner from within the 4 week period prior to presentation
• Advise sexual abstinence: min 1 week
• Block transmission: promote use of condoms

Question 10

Complications

Answer 10

Males:
- Acute and chronic prostatitis
- Increased risk of prostate cancer
- Infertility

Females:
- Perinatal complications: e.g. intrauterine growth restriction or pre-term delivery
- Increased risk of maternal postpartum sepsis
- Pelvic inflammatory disease (PID)
- Increased risk of bacterial vaginosis
- Increased risk of cervical cancer
- Infertility