Syphilis

Question 1

What organism cause syphilis

Answer 1

Treponema pallidum/spirochete

Question 2

Which antibiotics do we treat syphilis with

Answer 2

Benzathine penicillin given IM not IV

Question 3

What does a + treponemal antibody test mean (specific or not)

Answer 3

Specific to Treponema pallidum & mean exposure to syphilis (new or old infection)

Question 4

What does a + non-treponemal antibody test mean (specific or not)

Answer 4

Non-specific to Treponema pallidum
Track disease activity & treatment efficacy

Question 5

Which test do we use to monitor disease activity & response to therapy & titre meaning

Answer 5

Non-treponemal serology
Titre needs to decrease with 4 folds over 6 months

Question 6

What are the 2 clinical features of primary syphilis

Answer 6

Chancre formation @ site of infection & lymphadenopathy

Question 7

What are the 4 clinical features of secondary syphilis

Answer 7

Rash
Condylomata lata
Snail tract ulcers
Alopecia

Question 8

What are the 3 clinical features of tertiary syphilis

Answer 8

CVS: syphilis aortic aneurysm, dilated aorta, aortic valve regurgitation, coronary artery narrowing
Gummatous: non cancerous granulomatous growth in organs, bone & skin
Neurological: general paresis & tabes dorsalis

Question 9

What are the clinical features of early congenital syphilis

Answer 9

Still birth/neonatal death
Rash
Lymphadenopathy
Hepatomegaly
Splenomegaly
Rhinitis
CNS involvement
Pneumonitis
Intrauterine growth delay
Periosteitis

Question 10

How is syphilis transmitted

Answer 10

Sexual contact (adult)
Congenital (babies)
Blood borne (rare)

Question 11

What type of testing are mostly used to test for syphilis

Answer 11

Serology

Question 12

Why is syphilis known as the great imitator/imposter

Answer 12

Outer membrane has no protein or lipopolysaccharide & evade immune system

Question 13

What is the Pathogenesis of syphilis

Answer 13

1. Spirochete gain entry by penetrating the mucous membrane to establish primary infection
2. Multiply locally forming chancre & disseminate via lymph & blood to whole body
3. Antibody production, uptake & degradation of spirochete by phagocytes
4. Release of cytokines & initiation of adaptive immune response

Question 14

On what does clinical presentation of syphilis depend

Answer 14

The immune defence vs the pathogen ability to evade the immune system

Question 15

List the stages of syphilis from most infectious to least

Answer 15

Stage 2 (disseminated & high viral load)
Stage 1
Stage 3 is not infectious

Question 16

Is congenital syphilis preventable

Answer 16

Yes

Question 17

What is the sequence of syphilis testing

Answer 17

1. Screen w/ Treponemal test
2. Confirm w/ non-treponemal test

Question 18

What is the serology of Treponemal

Answer 18

1. IgM antibodies appear first then followed by IgG antibodies
2. Chancre appears 6-14 days after
3. IgM decrease & IgG increase & remains + lifelong

Question 19

What is the serology of non-treponemal

Answer 19

1. Not specific IgG & IgM antibodies released against spirochete that release cardiolipin
2. 10-15 days after lesion appear
3. Decrease with treatment & seroconverted, rarely serofast

Question 20

What is the window period of syphilis

Answer 20

6 weeks

Question 21

Name 6 instances when a false + syphilis test is present

Answer 21

Pregnancy, febrile disease, CT disorder, autoimmune, Hep C or low titre

Question 22

What do you call a false - syphilis test & why does it occur

Answer 22

Prozone effect
More antibodies present than antigen & Ag-Ab complex can not form optimally & requires serial dilution