STIs

Question 1

What are the risk factors for contracting STIs?

Answer 1

1. Multiple partners (two or more in the last year).
2. Concurrent partners.
3. Recent partner change (in past 3mths).
4. Non-use of barrier protection.
5. STI in partner.
6. Other STI.
7. Younger age (particularly aged ≤ 25yrs).
8. Involvement in the commercial sex industry

Question 2

What are the risk factors for contracting HIV (in addition to other risk factors)?

Answer 2

1. Men who have sex with other men
2. Those from countries of high HIV prevalence.
3. IVDUs
4. Any sexual partner of the above

Question 3

Used to be called cervical erosion!

What is cervical ectopy?

Answer 3

• Where cervical soft tissue is found on the outside of the cervix.
• Most common in women taking combined oral contraceptive pill, due to the oestrogen.
• Can cause post-coital or inter-menstrual vaginal bleeding and creamy watery discharge

Question 4

What are the diagnostic criteria for bacterial vaginosis?

Answer 4

At least 3 of:

• Positive potassium hydroxide “whiff” test
• ph >4.5
• > 20% clue cells on wet mount
• grey discharge

Question 5

What is vaginal thrush?

Answer 5

Infection with candidia albicans (fungus). Symptoms include itching and erythema.

Question 6

What is the type of bacteria that causes bacterial vaginosis?

Give an example antibiotic

Answer 6

Anaerobic bacteria.

Gardnerella vaginalis

Abx: e.g. metronidazole

Question 7

What are the 3 common infective causes of vulvovaginitis?

Answer 7

1. Bacterial vaginosis (anaerobic)
2. Vaginal thrush (candidia)
3. Trichomoniasis

Question 8

What are the 3 symptoms of trichomoniasis?

Answer 8

1. Offensive vaginal discharge
2. Post-coital bleeding
3. Erythema (strawberry cervix)

Question 9

Vaginal discharge with a fishy odour is most likely to be what?

Answer 9

Bacterial vaginosis (although this is asymptomatic in 50% of cases)

Question 10

What are the symptoms of chlamydia?

Answer 10

Most (70%) are asymptomatic

• Symptoms:
  
  • purulent discharge,
  • abnormal bleeding (postcoital or intermenstrual) due to cervicitis or endometritis
  • lower abdominal pain,
  • dyspareunia
  • dysuria

Question 11

How many patients with chlamydia develop PID?

Answer 11

10%

Question 12

How is chlamydia diagnosed?

Answer 12

Vulvovaginal (which can be self-taken) or endocervical swab for nucleic acid amplification test (NAAT)

Question 13

What are the symptoms of Gonorrhoea?

Answer 13

Up to 50% of women will be asymptomatic. Common symptoms may include:

• increased or altered vaginal discharge
• lower abdominal pain.
• It can also be a rare cause of heavy menstrual, postcoital or intermenstrual bleeding due to cervicitis or endometritis

Question 14

Which of the following are sexually transmitted?

1. Bacterial vaginosis?
2. Vaginal thrush?
3. Trichomonas vaginalis?

Answer 14

1. Bacterial vaginosis? NO
2. Vaginal thrush? NO
3. Trichomonas vaginalis? YES

Question 15

Which 3 types of HPV are high-risk types associated with cervical cancer?

Which are associated with genital warts?

Answer 15

1. Cancer: 16 (squamous carcinoma), 18 (adenocarcinoma) and 33.
2. Warts: 6 and 11

Question 16

What are the complications of chlamydia?

Answer 16

1. PID (10-40%)
2. Perihepatitis (Fitx-Hugh-Curtis syndrome)
3. Reiter’s syndrome (↑in men):
   
   1. arthritis
   2. urethritis
   3. conjuctivitis
4. Tubal infertility
5. Risk of ectopic pregnancy

Question 17

What characterises an episode of genital herpes (after the 7 day incubation period)?

Answer 17

First-episode: Malaise + fever + ulcers (can be so painful they cause urinary retention).

Question 18

What is the treatment for herpes?

Does it cure herpes?

Answer 18

Oral aciclovir

No; the infection remains in dorsal root ganglia and re-infection can occur throughout woman’s life.

Question 19

Genital herpes is infection by what virus?

Answer 19

15% Herpes Simplex Virus type 1

85% Herpes Simplex Virus type 2

Question 20

What is syphilis caused by?

Answer 20

Infection by spirochaete treponema pallidum

Question 21

What are the 2 routes of transmission of syphilis?

Answer 21

1. Acquired (contact with fluid - sex, needles, ulcer)
2. Congenital (mother to baby in utero or ex vagina)

Question 22

What is the first stage of syphilis?

Answer 22

Primary / early localised

→ painless ulcer / chancre

Question 23

What is the second stage of syphilis?

Answer 23

Secondary / disseminated syphilis

spirochetes are now in blood stream

→ lymphadenopathy

→ non-itchy maculopapular rash, starting at trunk and spreading out (VERY INFECTIOUS)

Question 24

What is the third stage of syphilis?

Answer 24

Latent syphilis:

1. Early stage (can look like secondary stage symptoms)
2. Late stage (complications):
   
   1. CNS
      
      1. tabes dorsalis (degeneration of spinal cord fibres)
   2. CVS
      
      1. aortitis
   3. Liver, joints, testes (caused by gummata

Question 25

Why does syphilis cause such damage to organs?

Answer 25

Because some of the **antigens** on the spirochetes are elsewhere in the body. The body mounts a huge **type 4 hypersensitivity** reaction, and **t-cell destruction** / formation of **gummata** cause a lot of **cellular damage**.

Question 26

What are the tests for syphilis?

Answer 26

Non-treponemal (not specific for syphilis) * VDRL (venereal disease research lab) test * RPR (rapid plasma reagin test) Treponemal * TPPA t-pallidum partical agglutination / TPHA * Enzyme immunoassay (EIA)