Capsule: GUM

Question 1

Syphilis causative organism

Answer 1

The spirochaete bacterium treponema pallidum

Question 2

Syphilis ix

Answer 2

Dark ground microscopy of ulcer samples, nontreponemal ab tests (VDRL & rapid plasma reagin), treponemal ab tests (haemagglutination assay & fluorescent ab testing)

NB: in primary syphilis where sx have only been px for a few days baseline testing may be -ve but should be +ve within 2w so repeat tests then

Question 3

Which ab do nontreponemal tests detect?

Answer 3

Cardiolipin

Question 4

Which abs are quantifiable?

Answer 4

Nontreponemal

Question 5

Which abs remain positive after tx?

Answer 5

Treponemal

Question 6

What should you always test for following a dx of syphilis?

Answer 6

HIV

Question 7

Syphilis tx

Answer 7

IM benzathine penicillin (oral doxycycline if penicillin allergic), full sexual health screen, hep B vac if MSM, partner notification, advise no sex regardless of protected or not until after tx

Question 8

What may occur after initiation of abx tx?

Answer 8

A Jarisch-Herxheimer reaction

Question 9

How does a Jarisch-Herxheimer reaction px?

Answer 9

Acute febrile illness w headache, myalgia, chills and rigors resolving <24 hrs

Question 10

Describe the relationship b/w a Jarisch–Herxheimer reaction and early/late syphilis

Answer 10

Early - common but usually not clinically sig

Late - uncommon but may be life-threatening

Question 11

When does the secondary vasculitic phase occur?

Answer 11

4-8w after primary infection

Question 12

When does gummatous syphilis occur?

Answer 12

3-12yrs after primary infection

Question 13

Where does gummatous syphilis usually affect?

Answer 13

Skin & bone

Question 14

When does neurosyphilis occur?

Answer 14

10-20yrs after primary infection

Question 15

What can neurosyphilis comprise of?

Answer 15

Psychosis, dementia, tabes dorsalis, Argyll-Robertson pupil

Question 16

What is tabes dorsalis?

Answer 16

The involvement of the posterior columns of the spinal cord (sensory ataxia, shooting pain, Charcot joints)

Question 17

What is the Argyll-Robertson pupil?

Answer 17

It is fixed and constricted that responds to accommodation but not to light

Question 18

How is neurosyphilis dx?

Answer 18

CSF

Question 19

When does cardiovascular syphilis occur?

Answer 19

10-30yrs after primary infection

Question 20

What can cardiovascular syphilis comprise of?

Answer 20

Aortitis, aneurysm of ascending aorta, aortic incompetence, heart failure

Question 21

When are syphilis pts most infectious?

Answer 21

During primary infection

Question 22

What can a widespread maculopapular rash in a pt w fever and malaise be indicative of?

Answer 22

HIV seroconversion or secondary syphilis

Ddx pityriasis rosea & guttate psoriasis

Question 23

When would you get a rash w EBV?

Answer 23

After concomitant amoxicillin administration

Question 24

What would a rash affecting the palms and soles be more indicative of?

Answer 24

Syphilis > HIV

Question 25

How long after exposure is HIV seroconversion illness likely to develop?

Answer 25

2-12w

Question 26

How long after exposure is secondary syphilis likely to develop?

Answer 26

6w-6m

Question 27

RFs for HIV transmission

Answer 27

Order of prevalence: MSM, heterosexual contact in sub-Saharan Africa, IVDU, vertical transmission

Question 28

How long is the window period for HIV post exposure prophylaxis?

Answer 28

72hrs

Question 29

Which features suggest PCP?

Answer 29

Dry cough over mnths, SOBOE, constitutional sx CXR - interstitial and bilateral hilar shadowing ABG - profoundly hypoxic w type 1 respiratory failure

Question 30

Where does cryptogenic fibrosing alveolitis typically affect?

Answer 30

Basal interstitial shadowing

Question 31

When is resp acidosis usually seen?

Answer 31

COPD or type 1 respiratory failure when they tire

Question 32

Difference b/w type 1 and type 2 respiratory failure

Answer 32

Type 1 - low/N CO2 - VQ mismatch Type 2 - high CO2 - inadequate alveolar ventilation

Question 33

How do you dx PCP?

Answer 33

Bronchoscopy, BAL, staining and PCR

Question 34

Tx for PCP

Answer 34

Oxygen, 3w co-trimoxazole or clindamycin/promaquine if allergic, steroids if PO2 <8kPa

Question 35

What is another name for co-trimoxazole?

Answer 35

Septrin

Question 36

What is the PCP prophylaxis for HIV-positive pts w CD4 <200?

Answer 36

1. Septrin 480mg OD 2. Dapsone 100mg OD