STIs Flashcards
What are the risk factors for contracting STIs?
- Multiple partners (two or more in the last year).
- Concurrent partners.
- Recent partner change (in past 3mths).
- Non-use of barrier protection.
- STI in partner.
- Other STI.
- Younger age (particularly aged ≤ 25yrs).
- Involvement in the commercial sex industry
What are the risk factors for contracting HIV (in addition to other risk factors)?
- Men who have sex with other men
- Those from countries of high HIV prevalence.
- IVDUs
- Any sexual partner of the above
Used to be called cervical erosion!
What is cervical ectopy?
- 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
What are the diagnostic criteria for bacterial vaginosis?
At least 3 of:
- Positive potassium hydroxide “whiff” test
- ph >4.5
- > 20% clue cells on wet mount
- grey discharge
What is vaginal thrush?
Infection with candidia albicans (fungus). Symptoms include itching and erythema.
What is the type of bacteria that causes bacterial vaginosis?
Give an example antibiotic
Anaerobic bacteria.
Gardnerella vaginalis
Abx: e.g. metronidazole
What are the 3 common infective causes of vulvovaginitis?
- Bacterial vaginosis (anaerobic)
- Vaginal thrush (candidia)
- Trichomoniasis
What are the 3 symptoms of trichomoniasis?
- Offensive vaginal discharge
- Post-coital bleeding
- Erythema (strawberry cervix)
Vaginal discharge with a fishy odour is most likely to be what?
Bacterial vaginosis (although this is asymptomatic in 50% of cases)
What are the symptoms of chlamydia?
Most (70%) are asymptomatic
- Symptoms:
- purulent discharge,
- abnormal bleeding (postcoital or intermenstrual) due to cervicitis or endometritis
- lower abdominal pain,
- dyspareunia
- dysuria
How many patients with chlamydia develop PID?
10%
How is chlamydia diagnosed?
Vulvovaginal (which can be self-taken) or endocervical swab for nucleic acid amplification test (NAAT)
What are the symptoms of Gonorrhoea?
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
Which of the following are sexually transmitted?
- Bacterial vaginosis?
- Vaginal thrush?
- Trichomonas vaginalis?
- Bacterial vaginosis? NO
- Vaginal thrush? NO
- Trichomonas vaginalis? YES
Which 3 types of HPV are high-risk types associated with cervical cancer?
Which are associated with genital warts?
- Cancer: 16 (squamous carcinoma), 18 (adenocarcinoma) and 33.
- Warts: 6 and 11
What are the complications of chlamydia?
- PID (10-40%)
- Perihepatitis (Fitx-Hugh-Curtis syndrome)
-
Reiter’s syndrome (↑in men):
- arthritis
- urethritis
- conjuctivitis
- Tubal infertility
- Risk of ectopic pregnancy
What characterises an episode of genital herpes (after the 7 day incubation period)?
First-episode: Malaise + fever + ulcers (can be so painful they cause urinary retention).
What is the treatment for herpes?
Does it cure herpes?
Oral aciclovir
No; the infection remains in dorsal root ganglia and re-infection can occur throughout woman’s life.
Genital herpes is infection by what virus?
15% Herpes Simplex Virus type 1
85% Herpes Simplex Virus type 2
What is syphilis caused by?
Infection by spirochaete treponema pallidum
What are the 2 routes of transmission of syphilis?
- Acquired (contact with fluid - sex, needles, ulcer)
- Congenital (mother to baby in utero or ex vagina)
What is the first stage of syphilis?
Primary / early localised
→ painless ulcer / chancre
What is the second stage of syphilis?
Secondary / disseminated syphilis
spirochetes are now in blood stream
→ lymphadenopathy
→ non-itchy maculopapular rash, starting at trunk and spreading out (VERY INFECTIOUS)
What is the third stage of syphilis?
Latent syphilis:
- Early stage (can look like secondary stage symptoms)
- Late stage (complications):
- CNS
- tabes dorsalis (degeneration of spinal cord fibres)
- CVS
- aortitis
- Liver, joints, testes (caused by gummata
- CNS
Why does syphilis cause such damage to organs?
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.
What are the tests for syphilis?
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)
