Tropical STIs Flashcards
Is Haemophilus Ducreyi a gram negative or positive bacteria
gram negative
what is the name of the causative organism that causes Chancroid?
Haemophilus Ducreyi
what is the incubation period of Chancroid?
short 4-7 days
how would you describe a Chancroid ulcer?
remember ‘S’ for Skankroid
Skanroid - skanky rough edged ulcer with a grey and yellow base, can bleed on contact
Sore = painful ulcers
Soft ulcer
how do ulcers develop in chancroid?
start as a papule develop into a pustule then into a rough edged, painful ulcer. rare to get extra-genital ulcers usually cause painful genital ulcers
what are some of the complications that can develop as a result of chancroid?
phimosis (inability to retract foreskin), partial tissue loss
what other signs other than genital ulcer disease can you develop and look for when examining a patient?
painful genital ulcers also develop lymphadenitis which is painful - this requires aspiration to prevent bubo
what is the best way to diagnose chancroid
PCR swab for detection (95% sensitivity) however no FDA approved test so in the UK we can do microscopy and look for gram negative rods (low sens and specificity) and also culture (but this can take time and need to use two different culture medium). Culture is better from the ulcer than from buboe.
what are the first line treatment options for chancroid
- azithromycin 1g stat or ceftriaxone 250mg IM stat (first line)
what are the second line treatment options for chancroid
erythromycin 500mg QDS for 7 days or ciprofloxacin 500mg BD for 3 days
note HIV patients better to give erythromycin or ciprofloxacin
how fast will the patient start to feel better once on antibiotic Rx for chancroid?
3 days symptomatic improvement, 7 days ulcer should be healed
What is the PN loopback period in chancroid
PN loopback period is 10 days from before symptom onset
where are donovanosis and chancroid most commonly seen in the World?
rare in western world, rates falling even in South africa and Papua new guinea
describe a typical donovanosis ulcer
beefy red ulcer, bleeds easily, is painless (note are four different types of donovanosis ulcers)
described above is the most commonly seen type known as ulcerogranulomatous
what are the main differences that could help you differentiate between donovanosis and chancroid
donovanosis - beefy red ulcer, bleeds easily, painLESS, don’t get lymphadenitis, but can get extra-genital ulcers
chancroid - painful, necrotic, looks ‘skanky’ rough edges, a/s with lymphadenitis and bubo formation
What is the name of the bacteria that causes donovanosis
Klebsiella granulomatosis
how do we diagnosis Donovanosis?
direct microscopy - see large mononuclear cells with intracyctoplasmic cysts filled with gram negative donovanosis bodies (DONOVAN BODIES) on giemsa stain
what is the treatment for donovanosis
azithromycin 1g OD for 3 weeks/ until lesions heal (or azithromycin 500mg PO OD 3/52 or until lesions have healed)
what is loopback for PN for donovanosis
6 months!!
describe the pathophysiology of how a donavanosis ulcer develops
starts as a papule –> ulcerates, slowly develops into a painless ulcer that is highly vascular
LGV is caused by which serovars of chlamydia trachomatis
L1-L3 (most commonly l2b) these serovars are more aggressive can infect macrophages and lymphocytes whereas servers D-K that cause urogenital CT usually just confined to mucous membranes
describe the bacterial morphology of LGV
gram negative intracellular obligate bacteria (same as CT)
which population/group in Europe are most commonly affected by LGV
MSMs - in 2003 outbreak in rotterdam prior to this was thought to be more of a tropical STI
rates of LGV cases are now falling in the UK
false -rates are at their highest
Talk through the pathophysiology and stages of LGV if it infects genito-anal region
If lGV infects the genito-anal sites then we get three classical stages (think of it abit like syphilis stages)
first stage = primary stage –> papule that develops into an ulcer (usually painless), often shallow and can be multiple - can look like HSV. this will often go unnoticed and heal within a week
secondary stage = local and regional dissemination that if infected genito-anal sites will get localised inguinal lymphadenopathy which can form buboes which can be become fluctuant. Often the lymphadenopathy is painful. Typically occur 10-30 days after primary lesion (note this is the most common manifestation of genital LGV in heterosexuals)
Tertiary stage = rupture of the buboes can cause sinuses and fistulae, complicated fibrotic stage with irreversible lymphedema
what is the most common presentation of LGV in HIV positive MSMs
haemorrhagic proctitis
describe how LGV would commonly present if infects the rectum (rather than genito-anal region)
haemorrhagic proctitis, common in MSMs especially HIV positive MSMs
symptoms include :-
1. rectal pain
2. bloody discharge from the rectum
3. change in bowel habit - usually constipation
4. tenesmus
note don’t normally get inguinal lymphadenopathy as rectum lymph doesn’t drain here instead lymph drains to para-rectal lymph nodes and internal iliac LNs
who does BASHH guidelines say we should test for LGV
if HIV +ve MSM test if CT positive at any site
anyone with proctitis
note sometimes the genital or anal swabs might be negative but actually need to swab the ulcer!
what is first line Rx for LGV?
doxycycline 100mg BD for 3 weeks
what do european guidelines say in regards to LGV testing
test all MSMs with rectal CT positive regardless of HIV status
how quickly should symptoms improve when started on Rx for LGV
within 1-2 weeks, no sex until symptoms resolved, Rx completed and partners have also been treated
do you need to do a TOC for LGV if completed first line doxycycline Rx
no - only do TOC if not using first line treatment
