Tropical STIs

Question 1

Is Haemophilus Ducreyi a gram negative or positive bacteria

Answer 1

gram negative

Question 1

what is the name of the causative organism that causes Chancroid?

Answer 1

Haemophilus Ducreyi

Question 2

what is the incubation period of Chancroid?

Answer 2

short 4-7 days

Question 3

how would you describe a Chancroid ulcer?

Answer 3

remember ‘S’ for Skankroid

Skanroid - skanky rough edged ulcer with a grey and yellow base, can bleed on contact

Sore = painful ulcers

Soft ulcer

Question 4

how do ulcers develop in chancroid?

Answer 4

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

Question 5

what are some of the complications that can develop as a result of chancroid?

Answer 5

phimosis (inability to retract foreskin), partial tissue loss

Question 6

what other signs other than genital ulcer disease can you develop and look for when examining a patient?

Answer 6

painful genital ulcers also develop lymphadenitis which is painful - this requires aspiration to prevent bubo

Question 7

what is the best way to diagnose chancroid

Answer 7

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.

Question 8

what are the first line treatment options for chancroid

Answer 8

1. azithromycin 1g stat or ceftriaxone 250mg IM stat (first line)

Question 9

what are the second line treatment options for chancroid

Answer 9

erythromycin 500mg QDS for 7 days or ciprofloxacin 500mg BD for 3 days

note HIV patients better to give erythromycin or ciprofloxacin

Question 10

how fast will the patient start to feel better once on antibiotic Rx for chancroid?

Answer 10

3 days symptomatic improvement, 7 days ulcer should be healed

Question 11

What is the PN loopback period in chancroid

Answer 11

PN loopback period is 10 days from before symptom onset

Question 12

where are donovanosis and chancroid most commonly seen in the World?

Answer 12

rare in western world, rates falling even in South africa and Papua new guinea

Question 13

describe a typical donovanosis ulcer

Answer 13

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

Question 14

what are the main differences that could help you differentiate between donovanosis and chancroid

Answer 14

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

Question 15

What is the name of the bacteria that causes donovanosis

Answer 15

Klebsiella granulomatosis

Question 16

how do we diagnosis Donovanosis?

Answer 16

direct microscopy - see large mononuclear cells with intracyctoplasmic cysts filled with gram negative donovanosis bodies (DONOVAN BODIES) on giemsa stain

Question 17

what is the treatment for donovanosis

Answer 17

azithromycin 1g OD for 3 weeks/ until lesions heal (or azithromycin 500mg PO OD 3/52 or until lesions have healed)

Question 18

what is loopback for PN for donovanosis

Answer 18

6 months!!

Question 19

describe the pathophysiology of how a donavanosis ulcer develops

Answer 19

starts as a papule –> ulcerates, slowly develops into a painless ulcer that is highly vascular

Question 20

LGV is caused by which serovars of chlamydia trachomatis

Answer 20

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

Question 21

describe the bacterial morphology of LGV

Answer 21

gram negative intracellular obligate bacteria (same as CT)

Question 22

which population/group in Europe are most commonly affected by LGV

Answer 22

MSMs - in 2003 outbreak in rotterdam prior to this was thought to be more of a tropical STI

Question 23

rates of LGV cases are now falling in the UK

Answer 23

false -rates are at their highest

Question 24

Talk through the pathophysiology and stages of LGV if it infects genito-anal region

Answer 24

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

Question 25

what is the most common presentation of LGV in HIV positive MSMs

Answer 25

haemorrhagic proctitis

Question 26

describe how LGV would commonly present if infects the rectum (rather than genito-anal region)

Answer 26

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

Question 27

who does BASHH guidelines say we should test for LGV

Answer 27

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!

Question 28

what is first line Rx for LGV?

Answer 28

doxycycline 100mg BD for 3 weeks

Question 29

what do european guidelines say in regards to LGV testing

Answer 29

test all MSMs with rectal CT positive regardless of HIV status

Question 30

how quickly should symptoms improve when started on Rx for LGV

Answer 30

within 1-2 weeks, no sex until symptoms resolved, Rx completed and partners have also been treated

Question 31

do you need to do a TOC for LGV if completed first line doxycycline Rx

Answer 31

no - only do TOC if not using first line treatment