Lecture 35: genital ulcers and genital lesions

Question 1

Epidemiology of syphilis

Answer 1

-Uncommon in NZ except MSM

Question 2

Pathology of syphilis?

Answer 2

• Spirochaetal infection
• T. pallidum
• Immune evasion responses important in maintenance of latency
• CMI is critical and to the control of proliferation of T. pallidum
• Immune response causes much of clinical disease

Question 3

Early manifestations of syphilis/Primary syphilis?

Answer 3

• Ulceration
• Rash
• Ocular lesions
• neurological signs

Question 4

Early confirmation of syphilis diagnosis?

Answer 4

• Dark field microscopy

- Direct fluorescent antibody test

Question 5

Secondary syphilis

Answer 5

-appears 4-10 weeks after primary lesions
-due to haematogenous spread therefore may have systemic symptoms
-rash: macular…papular…papulosquamous
-rash on trunk, extremeties, pamls and soles
-

Question 6

Late syphilis?

Answer 6

-no longer infectious

Question 7

Syphilis test

Answer 7

EIA test: overall pretty good, although might have to wit some timeas for primary syphilis not perfect
RPR: detects and AB against lipoidal Ag. Positive 3-5 weeks post exposure
TPPA: confirmatory, in early and late disease.

Question 8

Treatment for syphilis?

Answer 8

• Infected <2 years, benzathine penicillin IM
• Contacts are treated
• Allergy: doxycycline
• Pregnant: benzatine penicillin

Question 9

Herpes infection

Answer 9

Transmission: mucosa more vulnerable
Replicates in epidermis
Travels via unmyelinated sensory neurons, where it can enter a latent phase
HSV1 and HSV2

Question 10

Herpes treatment (Aciclovir facts)

Answer 10

Aciclovir- 15-20% bioavailability

• Activation involves viral thymidine kinase
• host cell metabolises to ACV triphosphate
• This competitively inhibits DNA polymerase, incorporates into DNA chain and terminates chain
• HSV resistance uncommon
• L-valine ester makes valaciclovir, more bioavailable

Question 11

Chlamydia trachomatis and serovars L1,L2 and L3 (most common here is L2)

Answer 11

Presentation depends on site, and gender: transient anogenital ulcer, cervicitis , proctitis
Causes lymphogranuloma vereneum

Question 12

HPV features

Answer 12

• DNA virus
• needs differentiating epithelial tissue to grow
• Anogenital warts it can cause, with some association with anogenital neoplasia
• E6 and E7 gene target TS genes and drive replication

Question 13

HPV complications

Answer 13

Intraepithelial neoplasia
Most are benign, small number can cause anogenital cancer.
Smoking and immune status important co-factors
cervical cancer well described
oro-pharyngeal cancer and anal cancer becoming important theme