STD

Question 1

[bacterial std] Chlamydia
- caused by___
obligate intracellular bacteria (means that we cannot “grow” this organism on routine culture)
- Genital chlamydia infection is mostly ____ (symptomatic/asymptomatic)

Answer 1

Chlamydia
- caused by Chlamydia trachomatis obligate intracellular bacteria
(means that we cannot “grow” this organism on routine culture)
- Genital chlamydia infection is mostly asymptomatic

Question 2

common genital chlyamidia in male and female respectively

Answer 2

male: urethritis, female:PID

Question 3

Complication of chlamydia: PID in women (4), pregnant and newborns?

PID also in gonorrhea

Answer 3

infertility, tubo-ovarian abscess,
ectopic pregnancy,
chronic pelvic pain

Pregnant women:
Risk of premature rupture of membranes,
preterm delivery, low birth weight infants

Newborns:
C. trachomatis acquired through an infected
birth canal ⇒ neonatal conjunctivitis and
pneumonia

Question 4

Chlamydia diagnosis [test+ specimen] MS no C as it is hard to grow

Answer 4

M/Test:
- Nucleic Acid Amplification
Test (NAAT, or, PCR)
* test of choice
* detects chlamydia DNA or RNA
* no routine culture

Specimen:
women: vaginal or endocervical swab
(specimen of choice)
OR first catch urine

men: first catch urine
(specimen of choice) OR
urethral swab

Question 5

[bacterial std] Neisseria gonorrhoea
- (symptomatic/asymptomatic) carriage is major reservoir
- Clinical presentation in men and women very ____

Answer 5

Neisseria gonorrhoea
- Asymptomatic carriage is major reservoir
- Clinical presentation in men and women very different

Question 6

Male vs female genital gonorrhea

Answer 6

Male: early and symptomatic eg urethritis and prostatitis

Female: asymptomatic

Question 7

Extra-genital gonorrhea complications (3)

Answer 7

pharyngitis,
conjunctivitis,
disseminated gonococcal infection (bloodstream infection)

Question 8

gonorrhea diagnosis [test+ specimen] MC no S

Answer 8

M/ test: NAAT/nucleic acid amplification test (or PCR)
Culture: swab or pus or urine. PCR does not need alive bacteria.
* cannot perform antibiotic susceptibility testing

Question 9

[bacterial std] Syphilis 3 stages [FYI]

just know its pri, sec and tertiary. no need memorise

Answer 9

1. painless sore (chancre) at inoculation
2. dissemination
3. CNS and CVS affected

Question 10

Syphilis mode of transmission

Answer 10

• sexual / intimate contact
  with infectious lesions
  - blood transfusion
• transplacental ⇒
  congenital syphilis

Question 11

syphilis diagnosis

Answer 11

• Serology (antibody detection)
• screening test:
  Non-treponemal antibody testing e.g. VDRL, RPR
• confirmatory test: Treponemal specific antibody testing e.g. Enzyme-immunoassay, TPPA

Question 12

[viral STD] Human
Papilloma Virus (HPV): transmission mode and characteristics (3 types)

Answer 12

• direct skin-to-skin contact
• primary infection: may be asymptomatic, or mild symptoms. Genital warts or non-genital warts
• resolution of infection: may spontaneously resolve
• persistent infection: persistent infection with
  high-risk
• HPV types. Increases the risk of cancer e.g. cervical, anal, oro-pharyngeal