Lecture 12: STIs Flashcards
STIs require ____ contact for transmission and ____ ____ to allow for occasional opportunities for transmission. They may remain as ____ infections or may ____. They can be an important cause of ____ disease
intimate, persistent infection, local, disseminate, neonatal
Bacterial STI
chlamydia, gonorrhoea, syphilis
Viral STI
HPV, herpes, HIV
Fungal STI
candidiasis
Protozoal STI
trichomoniasis
more than ____ STIs are aquired every day worldwide. Each year there is an estimated ____ million new infections with ____ of ____ curable STIs: chlamydia, gonorrhoea, syphilis and trichnomiasis. More than ____ million 15-49 year old estimated to have genital infectin with HSV
one million, 376, one of four, 500
What are some common symptoms of STIs
- Urethritis - can be purulent
- Cervicitis - can be purulent
- Epididymitis - chronic pain, infertility, hypogonadism, defective hormone production
What are some complications of untreated symptoms?
PID - uterus, fallopian tubes, ovaries
can lead to ectopic pregancy, infertility and chronic pelvic pain
Chlamydia is caused by the bacterium ____ ____. ____ serovars are classified by prominent outer membrane protein ____
Chlamydia thrachomatis, a-k, OmpA (virulence factor)
What is the function of serovars in chlamydia?
A-C infect conjunctival epithelial cells - blindness.
D-K infect genital tract epithelial cells - pelvic inflammatory disease, ectopic pregnancy, and sterility
L1-L3 infect epithelial cells and macrophages, causing an invasive infection.
Lymphgranuloma venereum (LGV) can infect ____ and spreads through ____. it is predominantely found in ____. It causes ____ in the groin and ____ which is inflammation of the colon and rectum
macrophages, lymph nodes, men who have sex with men, buboes, proctocolitis
gential serovars transmission
transmitted vaginally, orally and anally
can be passed to baby during childbirth
> 70% women asymptomatic
~ 25% men asymptomatic
can be cured with AB
if genital serovars are left untreated they can lead to ____ , which manifests as ____ ____ and ____ .
PID, chronic pelvic pain, ectopic pregnancy, infertility
genital serovars can lead to ____ ____ and ____ in babies born vaginally to infected women. In untreated men can lead to pain, swelling and inflammation of the ____ and ____ , ____ , ____ and ____
Neonatal, conjunctivitis, pneumonia, epididymis, testes, urethritis, reactive arthritis, infertility
how many people are infected with Chlamydia in nz per year? how is this data acquired
28,000, voluntary provision of data
(almost double rates of UK and Australia)
incidence of chlamydia is highest in which demographic?
20-24 y/olds
how is chlamydia diagnosed?
culture from swab or urine
PCR amplification of DNA
Antigen detection by microscopy or ELISA
____ and ____ are not effective in treating chlamydia. A single dose of ____ is currently the recommended first line treatment and is effective in 94% of patients but is less effective in treating ____ chlamydia. BPAC recommend ____, 100 mg twice a day for seven days
penicillin, cephalosporins, azithromycin, rectal, doxycyline
What is the EB in chlamydia infection?
elementary body - metabolically inactive but highly infectious
What is RB in chlamydia infection?
Reticulate body - metabolically active and replicative form
Explain the pathogenesis of chlamydia
- EB enters cell, transforms IB and then RB
- RB begins to divide within inclusion memrbane, T3SS needles penetrate IM to secrete effectors
- RBs begin to differentiate back into EBs
- Infectious EB escape by cell lysis or extrusion to initiate new infection
Gonorrhoea is caused by bacterium ____ ____ and ____ most prevalent bacterial STI
Neisseria gonorrhoeae, second
gonorrhoea is transmitted during ____ sex. Female to male = ____% / episode, male to female = ____ % /episode. Can be passed to baby during childbirth.
vaginal, oral, anal, 20%, 50%
Gonorrhoea symptoms and what happens if left untreated?
- pain and inflammation/buring during urination
- systemic dissemination
Gonorrhoea became a notifiable disease under the health act in 2017. ____/100000 population.
75
Incidence of gonorrhoea is higher in?
males than females
(98 vs 66 cases per 100,000)
What age demographic is most affected by gonorrhoea
20-24 y olds
Treatment for gonorrhoea
penicillin initially effective (MIC <0.01mg/L) - now accumulation of mutations in porins, aquisition of gene for new transpeptidase. MIC now 1 mg/L. Then plasmid with gene for beta-lactamase - MIC now > 64 ml/L
so now intramuscular ciprofloxacin treatment with oral azithromycin (attacks chlamydia too)
Syphilis caused by ____ ____
treponema pallidum
In syphilis the infection is ____ with a visible ____. a painless ulcer that heals spontaneously
local, chancre
if syphilis is left untreated, it leads to secodary disease in ____ weeks resulting in ____ ____ which is a widespread rash
2-8 weeks
bacteriaemic dissemination
Symptoms of syphilis include
rash, fever, malaise, aseptic meningitis, hepatitis
If syphilis is left untreated it can lead to teritaty disease years later and manifests as ___ ___ _ . inflammation of blood vessles affecting the brain and artery
small vessel vasculits
In pregnant women, untreated syphilis leads to ____ or ____ in half of pregnancies.
miscarriage, still birth
What is the treatment for syphilis?
penicillin - no resistance
