Syphilis

Question 1

What is syphilis?

Answer 1

Syphilis is caused by bacteria called 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. It is mainly a sexually transmitted infection. The incubation period between the initial infection and symptoms is 21 days on average.

Question 2

How is sylphilis transmitted?

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

What are the stages of syphilis?

Answer 3

• Primary syphilis
• Secondary syphilis
• Latent syphilis
• Tertiary syphilis
• Neurosyphilis

Question 4

What is primary syphilis?

Answer 4

Primary syphilis involves a painless ulcer called a chancre at the original site of infection (usually on the genitals).

Question 5

What is secondary syphilis?

Answer 5

Secondary syphilis involves systemic symptoms, particularly of the skin and mucous membranes. These symptoms can resolve after 3-12 weeks and the patient can enter the latent stage.

Question 6

What is latent syphilis?

Answer 6

Latent syphilis occurs after the secondary stage of syphilis, where symptoms disappear and the patient becomes asymptomatic despite still being infected. Early latent syphilis occurs within two years of the initial infection, and late latent syphilis occurs from two years after the initial infection onwards.

Question 7

What is tertiary syphilis?

Answer 7

Tertiary syphilis can occur many years after the initial infection and affect many organs of the body, particularly with the development of gummas and cardiovascular and neurological complications.

Question 8

What is neurosyphilis?

Answer 8

Neurosyphilis occurs if the infection involves the central nervous system, presenting with neurological symptoms.

Question 9

How does primary syphilis present?

Answer 9

Primary syphilis can present with:

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

Question 10

How does secondary syphilis present?

Answer 10

Secondary syphilis 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 11

How does tertiary syphilis present?

Answer 11

Tertiary syphilis can present with several symptoms depending on the affected organs. Key features to be aware of are:

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

Question 12

How does neurosyphilis present?

Answer 12

Neurosyphilis can occur at any stage if the infection reaches the central nervous system, and present with symptoms of:

• Headache
• Altered behaviour
• Dementia
• Tabes dorsalis (demyelination affecting the spinal cord posterior columns)
• Ocular syphilis (affecting the eyes)
• Paralysis
• Sensory impairment

Question 13

What opthalmological pupil is characteristic of neurosyphilis?

Answer 13

Argyll-Robertson pupil is a specific finding in neurosyphilis.

Question 14

Briefly describe a Argyll-Robertson pupil

Answer 14

Argyll-Robertson pupil is a specific finding in neurosyphilis. It is a constricted pupil that accommodates when focusing on a near object but does not react to light. They are often irregularly shaped. It is commonly called a “prostitutes pupil” due to the relation to neurosyphilis and because “it accommodates but does not react“.

Question 15

Briefly describe the diagnosis of syphilis

Answer 15

Antibody testing for antibodies to the T. pallidum bacteria can be used as a screening test for syphilis.

Patients with suspected syphilis or positive antibodies should be referred to a specialist GUM centre for further testing.

Samples from sites of infection can be tested to confirm the presence of T. pallidum with:

• Dark field microscopy
• Polymerase chain reaction (PCR)

Question 16

Briefly describe the use of rapid plasma reagin (RPR) and venereal disease research laboratory (VDRL) in diagnosing syphilis

Answer 16

The rapid plasma reagin (RPR) and venereal disease research laboratory (VDRL) tests are two non-specific but sensitive tests used to assess for active syphilis infection. These tests assess the quantity of antibodies being produced by the body to an infection with syphilis. A higher number indicates a greater chance of active disease. These tests involve introducing a sample of serum to a solution containing antigens and assessing the reaction. A more significant reaction suggests a higher quantity of antibodies. The tests are non-specific, meaning they often produce false-positive results. There is a skill to both performing and interpreting the results of these tests.

Question 17

What other factors need to be considered when treating syphilis?

Answer 17

All patients should be managed and followed up by a specialist service, such as GUM. As with all sexually transmitted infections, patients need:

• Full screening for other STIs
• Advice about avoiding sexual activity until treated
• Contact tracing
• Prevention of future infections

Question 18

Briefly describe the treatment of syphilis

Answer 18

A single deep intramuscular dose of benzathine benzylpenicillin (penicillin) is the standard treatment for syphilis.

Alternative regimes and types of penicillin are used in different scenarios, for example, late syphilis and neurosyphilis. Ceftriaxone, amoxicillin and doxycycline are alternatives.