Syphilis

Question 1

Which species causes syphilis?

Answer 1

treponema pallidum, subspecies pallidum

Question 2

What are the characteristics of primary Syphilis?

Answer 2

• single painless ulcer -> highly infectious
• widespread dissemination
• lymphadenopathy
• often undetectable
• ulcers heal spontaneously but individual is still infected

Question 3

What is the name for the ulcers found in syphilis?

Answer 3

chancres

Question 4

What are the characteristics of secondary syphilis?

Answer 4

-3-6 months after initial infection
- widespread mucocutaneous rash
-widespread dissemination of treponema throughout the body -> rash, alopecia, lymphadenopathy (swelling or enlargement of lymph nodes)

Question 5

What are the characteristics of tertiary syphilis?

Answer 5

-20-40 years after initial exposure
-leads to Gumma: nodular like lesions
- cardiovascular syphilis: aortic aneurism
- neurosyphilis = syphilitic gait caused by tabes gorsalis

Question 6

What is tertiary syphilis so destructive?

Answer 6

occurs months/ years after contact

1) Has granulomatous lesions that secrete treponema’s = highly infectious
2) destroys skin, tissues, bone, brain and heart
3) cardiovascular syphillis

Question 7

What are the features of congenital syphilis?

Answer 7

-early onset: 2-10 weeks post delivery of foetus
-sniffles, skin lesions, death, bleeding in the lungs, pulmonary haemorrhage, hepatitis

Question 8

Describe the causative microorganism behind syphilis:

Answer 8

Treponema

-has 3 periplasmic flagella -> exhibits corkscrew motility
-has limited metabolic capacity, can only grow in vivo and cannot be cultured in the lab
- slow doubling time
-sensitive to antibiotics

Question 9

Describe the virulence factors for treponema

Answer 9

1) Attachment: Uses Tp0155 (binds to fibronectin) and Tp0483 to bind to surfaces
2) Invasion: Hyaluronidase production = molecular mimicry
3) Motility: corkscrew motion

Question 10

How can syphilis be diagnosed?

Answer 10

direct microscopy/dark ground microscopy (light is scattered by motile treponema’s) and serological assays

Question 11

What does Venereal Disease research Laboratory detect?

Answer 11

IgM and IgG antibodies against lipoidal antigens released as a consequence of cell damage from host and bacterium

Question 12

Which antibodies can be found in serological test samples (VDRL)?

Answer 12

-IgM and IgG antibodies

Question 13

Describe the Treponema Palladium Haemagglutination Assay

Answer 13

• treponema pallidum antigen coated onto RBC
  -haemagglutination = positive result
  -buttoning of RBC = negative result

shows amount of treponema in patients blood

Question 14

Describe fluorescent treponema antibody absorption test

Answer 14

-T.Pallidum is fixed onto the slide with acetone and incubated with patient serum
-Incubated with anti human antibody conjugate FITC AND A SECONDARY ANTIBODY
- detects patients antibodies to treponema

Question 15

How did they used to treat syphilis before?

Answer 15

mercury and arsenic- 19th/20th century
penicillin- 21st century