STI

Question 1

patient states she suffers PV bleeding, particularly post coital but also intermenstrual

what are the major things to worry about?

Answer 1

cervical cancer needs to be considered.

However, chlamydia may present with this. would be important to screen for this before heading down biopsy pathway

Question 2

which is not a complication of chlamydia during pregnancy?

PPROM
pre-term birth
miscarriage
neonatal conjunctivitis

Answer 2

miscarriage.

while it has been associated with late term complications, miscarriage is not one of the well described issues

Question 3

how do we diagnose chlamydia?

how do we treat?

Answer 3

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

Question 4

why does chlamydia cause re-infection so often?

Answer 4

there is no long term immunity for this bug. ? is that because it’s an intracellular organism?

Question 5

what causes lymphogranuloma vererum (LGV)?

Answer 5

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

Question 6

what are some of the skin findings associated with Reiter’s syndrome?

Answer 6

it can cause a number of findings, including keratoderma blenorrhagica or erythema nodosum

it can cause SpA type findings or mono-oligo arthropathy

Question 7

what is the association between gonorrhoea and HIV?

Answer 7

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

Question 8

what is the most common clinical symptoms of gonorrhoea in women?

what about male non-genital tract infection?

what about penile infection?

Answer 8

most commonly this condition is asymptomatic except for men, where it is associated with discharge

(women around 50% asymptomatic)

Question 9

what is the classical triad of disseminated neisseria infection?

any other common syndromes?

Answer 9

tenosynovitis
dermatitis - often purulent looking
polyarthralgia

the isolated purulent joint is NOT usually associated with the rest of the triad

Question 10

how do we diagnose gonorrhoea?

how do we treat?

Answer 10

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)

Question 11

what is chancroid?

Answer 11

STI with painful genital ulcers

caused by a fastidious gram neg, Haemophilus ducreyi

Question 12

what are the HPV serotypes cause highest grade of cervical dysplasia

which ones cause warts?

Answer 12

dysplasia = 16 and 18

warts = 6 and 11

Question 13

what percentage of people have lifetime exposure to HSV1? HSV2?

Answer 13

i don’t know why people would think we should know this, but

HSV1 = 80%
HSV2 = 30%

Question 14

what’s the distribution of HSV1 v HSV2?

Answer 14

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

Question 15

which type of HSV tends to cause more of aseptic meningitis?

Answer 15

HSV2 > HSV1
women > men

in fact, some people have recurrent benign meningitis

Question 16

how do we treat HSV?

Answer 16

aciclovir is the standard.

valaciclovir is the longer halflife version of aciclovir

topical treatment don’t work

Question 17

how do you treat pediculosis pubis?

Answer 17

pubic lice need permethrin 1% cream

apply to the body hair and leave for 12 hours then repeat 1 week later

Question 18

how do you treat sarcoptes scabiei?

Answer 18

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)

Question 19

what is the bug in syphilis called?

Answer 19

Treponema pallidum pallidum

Question 20

how does syphilis cause disease?

Answer 20

it primarily causes an endarteritis obliterans with an associated mixed immune response

it is highly invasive and presents 9 - 90 days after

Question 21

what are the stages of syphilis?

Answer 21

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)

Question 22

what is neurosyphilis? when does it occur?

Answer 22

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.

Question 23

tertiary syphilis can cause what types of presentations?

Answer 23

cardiovascular disease can be aortitis and aneurysms

neurosyphilis can cause dementia, eye problems, tabes

gummatous syphilis is localised tissue and bone destruction

Question 24

what sort of problems are caused by syphilis in pregnancy?

Answer 24

this can cause perinatal death, low birth weight

congenital abnormalities, including deafness and neurological impairment

Question 25

what are the tests we use in syphilis?

Answer 25

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

Question 26

What is the Jarisch-Herxheimer reaction?

Answer 26

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

Question 27

how does one monitor response to treatment of syphilis?

Answer 27

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