STI Flashcards
patient states she suffers PV bleeding, particularly post coital but also intermenstrual
what are the major things to worry about?
cervical cancer needs to be considered.
However, chlamydia may present with this. would be important to screen for this before heading down biopsy pathway
which is not a complication of chlamydia during pregnancy?
PPROM
pre-term birth
miscarriage
neonatal conjunctivitis
miscarriage.
while it has been associated with late term complications, miscarriage is not one of the well described issues
how do we diagnose chlamydia?
how do we treat?
it is a DNA PCR
we should take a first pass urine or a swab
treat with a single dose of azithromycin 1 gram
patient shouldn’t have sex for 7 days
why does chlamydia cause re-infection so often?
there is no long term immunity for this bug. ? is that because it’s an intracellular organism?
what causes lymphogranuloma vererum (LGV)?
this is caused by the L1-L3 serovars of Chlamydia trachomatis
it is pretty rare in the West, but is increasing in HIV pos MSM
-in that population it can present atypically.
Ano rectal disease can occur and can mimic cancer
what are some of the skin findings associated with Reiter’s syndrome?
it can cause a number of findings, including keratoderma blenorrhagica or erythema nodosum
it can cause SpA type findings or mono-oligo arthropathy
what is the association between gonorrhoea and HIV?
apparently in gonorrhoea positive men, their semen contained 8x increase in HIV RNA.
treatment of this infection led to dramatic lowering of this
they tend to overlap too
what is the most common clinical symptoms of gonorrhoea in women?
what about male non-genital tract infection?
what about penile infection?
most commonly this condition is asymptomatic except for men, where it is associated with discharge
(women around 50% asymptomatic)
what is the classical triad of disseminated neisseria infection?
any other common syndromes?
tenosynovitis
dermatitis - often purulent looking
polyarthralgia
the isolated purulent joint is NOT usually associated with the rest of the triad
how do we diagnose gonorrhoea?
how do we treat?
it can be done on first pass urine or swabs of the affected site
however, it is also necessary to perform a culture to track sensitivities
the treatment is just ceftriaxone 500mg IM, but we co-administer with azithromycin due to possible chlamydia co-infection. There is POSSIBLE synergy
these patients MUST be followed up with clearance testing, due to the rising resistance rates (could be at risk of a recurrent infection though)
what is chancroid?
STI with painful genital ulcers
caused by a fastidious gram neg, Haemophilus ducreyi
what are the HPV serotypes cause highest grade of cervical dysplasia
which ones cause warts?
dysplasia = 16 and 18
warts = 6 and 11
what percentage of people have lifetime exposure to HSV1? HSV2?
i don’t know why people would think we should know this, but
HSV1 = 80% HSV2 = 30%
what’s the distribution of HSV1 v HSV2?
HSV1 can occur anywhere. Oral ulcers in childhood are the most common manifestation
HSV2 tends to be underpants distribution
- recurrence is very common in this condition. It is almost exclusively sexually transmitted
which type of HSV tends to cause more of aseptic meningitis?
HSV2 > HSV1
women > men
in fact, some people have recurrent benign meningitis
how do we treat HSV?
aciclovir is the standard.
valaciclovir is the longer halflife version of aciclovir
topical treatment don’t work
how do you treat pediculosis pubis?
pubic lice need permethrin 1% cream
apply to the body hair and leave for 12 hours then repeat 1 week later
how do you treat sarcoptes scabiei?
normal infection with permethrin 5% cream (note this is more potent than the 1%)
if the patient has crusted (Norwegian) scabies, then we also give ivermectin (oral agent)
what is the bug in syphilis called?
Treponema pallidum pallidum
how does syphilis cause disease?
it primarily causes an endarteritis obliterans with an associated mixed immune response
it is highly invasive and presents 9 - 90 days after
what are the stages of syphilis?
primary is painless indurated ulcer. It is called a chancre and heals spontaneously
secondary results from systemic spread. This occurs weeks-months after the chancre (but also can co-exist). This is associated with an immune complex response and vasculitis. This can cause a rash of palms and soles. This can also spontaneously relapse.
latent - asymptomatic carriage
tertiary is late disease and can have cardiovascular, neurological or gummatous. Don’t forget that the neurological can be tabes (dorsal column, sensory ataxia, argyll-robertson) or dementia paralytica (rapid progressive dementia with personality change)
what is neurosyphilis? when does it occur?
this is a condition that can occur at any stage of infection. Statistically it is most common during secondary. The risk is higher with a higher RPR
During secondary syphilis the bug actually disseminates widely and CSF infection is common.
tertiary syphilis can cause what types of presentations?
cardiovascular disease can be aortitis and aneurysms
neurosyphilis can cause dementia, eye problems, tabes
gummatous syphilis is localised tissue and bone destruction
what sort of problems are caused by syphilis in pregnancy?
this can cause perinatal death, low birth weight
congenital abnormalities, including deafness and neurological impairment
what are the tests we use in syphilis?
there are two types
non-specific = RPR (VRDL). This is used to monitor treatment and reinfection. Unfortunately has a higher number of false positives
specific tests = EIA, TPPA, TPHA, FTA-Abs. Usually these are reactive for a lifetime. One would usually screen with EIA and then confirm with another specific test
the role of RPR is that it gives us a titre, and that is useful to monitor response to treatment
you can also PCR a lesion
Dark field microscopy is done rarely
What is the Jarisch-Herxheimer reaction?
this is an acute febrile reaction within first 24 hours of treatment. It is a response to the the LPS being released by dying spirochetes
how does one monitor response to treatment of syphilis?
we are looking for a change of 4 fold. Decrease in the titre is best.
reinfection is suggested with a 4 fold rise in titre
