STI's: Syphillis

Question 1

Definition

Answer 1

Treponema pallidum. This bacteria is a spirochete, a type of spiral-shaped bacteria.
- The bacteria gets in through skin or mucous membranes, replicates and then disseminates throughout the body.
- The incubation period between the initial infection and symptoms is 21 days on average.

Question 2

Transmission

Answer 2

Syphilis can also be contracted through:
- Oral, vaginal or anal sex involving direct contact with an infected area
- Vertical transmission from mother to baby during pregnancy
- Intravenous drug use
- Blood transfusions and other transplants (although this is rare due to screening of blood products)

Question 3

Presentation (Primary)

Answer 3

A painless genital ulcer (chancre). This tends to resolve over 3 – 8 weeks.
Local lymphadenopathy

Question 4

Presentation (secondary)

Answer 4

Typically starts after the chancre has healed, with symptoms of:
- Maculopapular rash
- Condylomata lata (grey wart-like lesions around the genitals and anus)
- Low-grade fever
- Lymphadenopathy
- Alopecia (localised hair loss)
- Oral lesions

Question 5

Presentation (Tertiary)

Answer 5

• Gummatous lesions (gummas are granulomatous lesions that can affect the skin, organs and bones)
• Aortic aneurysms
• Neurosyphilis

Question 6

Diagnosis

Answer 6

FIRST LINE = Rapid plasma reagin (RPR) and venereal disease research labratory (VDRL)
Antibody testing for antibodies to the T.pallium bacteria can be used as a screening test for syphilis
GOLD STANDARD = Samples from sites of infection can be tested to confirm the presence of T. pallidum with:
- Dark field microscopy
- Polymerase chain reaction (PCR)

Question 7

Management

Answer 7

A single deep intramuscular dose of benzathine benzylpenicillin (penicillin) is the standard treatment for syphilis.
- Ceftriaxone, amoxicillin or doxycycline = Alternatives