Sexually transmitted diseases

Question 1

Describe how common sexually transmitted
diseases present, their long term consequences
and how awareness has reduced the STD burden
in the developed world

Answer 1

LOs: How well do you know these?

Question 2

Why are STDs difficult to control?

Answer 2

Increasing density/mobility in populations, difficulty in changing human behaviour, absence of vaccines for all apart from HPV

Question 3

What is the urogenital tract?

Answer 3

the organs of the reproductive system and the urinary system.

Question 4

Why can microorganisms spread easilhy from on easpect of the urogenital tract to another?

Answer 4

It is continuous, so microorganisms can spread easily from one part to another

Question 5

How is lactic acid produced in the vagina to inhibit colonisation

Answer 5

Glycogen produced as a by-product causes lactobacilli to colonise, producing lactic acid

Question 6

How does syphilis enter the body?

Answer 6

Via (treponema pallidum) minute abrasions skin/mucous membranes (does not survive outside body well, sensitive to drying, heat, and disinfectants). Can also be transmitted vertically

Question 7

What are the stages of syphilis

Answer 7

(initial contact) primary, secondary, latent, tertiary

Question 8

When is primary syphilis and what are its signs

Answer 8

2-10 weeks after infection. Observe enlarged inguinal nodes, spontaneous healing

Question 9

When is secondary syphilis observed and what are the signs

Answer 9

1-3 months after primary syphilis, shows flu-like illness, with illness, myalgia, headache, fever, MSK rash and spontaneous resolution

This is beacuse of multiplications and lesion production in lymph nodes, liver joints, muscles, skin, mucous membranes

Question 10

How long is syphilis latent for?

Answer 10

3-30 years, as treponemas dormant in liver/spleen

Question 11

What can happen with tertiary syphilis?

Answer 11

Neurosyphilis, cardiovascular syphilis, aortic lesions, heart failure.

Sparked by dissemination and invasion, host respinse

Question 12

What is neurosyphilis

Answer 12

Neurosyphilis refers to infection of the central nervous system in a patient with syphilis and can occur at any stage.

Question 13

What are the 3 ways that vertical transmission of T Pallidum can affect a baby

Answer 13

Serious infection causing intrauterine death,
Congenital abnormalities which may be obvious at birth
Silent infection which may not be apparent until about 2 years age (facial deformity)

Question 14

WHy are non-specific tests called non-specific?

Answer 14

The produce a non-specific antibody that reacts to cardiolipin

Question 15

What are the two non-specific tests?

Answer 15

Venereal disease research laboratory test (VDRL) or rpaid plasma reagin (RPR)

Question 16

What specific tests can be used to identify T Pallidum

Answer 16

Enzyme linked immunosorbent assay (ELISA) detects IgM and IgG,

Fluorescent treponemal antibody absorption (FTA-ABS) finds reaction woth antigens,

Microhaemagglutination assay for T pallidum

Question 17

WHat is the main useful drug in treating syphillis/T Palladum

Answer 17

Penicillin

Question 18

How can secondary and tertiary disease be effectively prevented

Answer 18

Early diagnosis and adequate treatment, including contact screening (patients with other STIs should be screened)

Question 19

WHat organism causes gonorrhoea

Answer 19

The gram negative coccus “Neisseria gonorrhoeae”

Question 20

How does gonorrhoea present within 2-7 days

Answer 20

In male there is urethral discharge and pain passing urine (dysuria)

In females is vaginal discharge

Question 21

How does gonorrhoea affect the GU system?

Answer 21

Pelvic inflammatory disease (PID), Chronic pelvic pain, or infertility due to damage to fallopian tubes

Question 22

What tests are done to identify gonorrhoea

Answer 22

Microscopy and culture, molecular tests

Question 23

Does Chlamydia invade host cells

Answer 23

Yes, but it is caused by a bacterium, not a virus

Question 24

What organism causes chlamydia

Answer 24

Chlamydia trachomatis serotypes D-K cause sexually transmitted genital infections

Question 25

How can chlamydia effect males

Answer 25

Urethritis, epididymitis (tube at back of testes) proctitis (inflammation of inner rectal lining) and conjunctivitis

Systemic spread, reiters syndrome

Question 26

How can women be affected by chlamydia

Answer 26

Urethritis, cervicitis, Bartholinitis (inflammation of bartholin glands by vagina) salpingitis (fallopian tubes) and conjunctivitis, Also can cause etopic pregancy (egg implants outside womb) infertility, perihepatitis, arthritis dermatitis

Question 27

How can neonates be affected by chlamydia

Answer 27

Conjuntivitis, pneumonia

Question 28

Wow does chlamydia enter the body?

Answer 28

Chlamydiae enter the host through minute abrasions in the mucosal surface

Question 29

How is chlamydial infection treated?

Answer 29

with doxycycline or azithromycin

Question 30

What 2 viruses are most common

Answer 30

HSV 1 and HSV 2

Question 31

How does genital herpes present

Answer 31

Ulcerating vesicles that take up to 2 weeks to heal

Question 32

How do recurrent cold sores form

Answer 32

the virus in the lesion travels up sensory nerve endings to establish latent infection in dorsal root ganglion neurones. From this site it can reactivate, travel down nerves to the same area, and cause recurrent lesions (‘genital cold sores’).

Aseptic meningitis/encephalitis are rare complications

Question 33

How is genital herpes diagnosed?

Answer 33

Clinical apperance, but HSV DNA can be detected and typed in vesicle fluid/ulcer swabs

Question 34

WHat is genital herpes treated with

Answer 34

Aciclovir

Question 35

What types of HPV are linked to genital warts

Answer 35

11 and 16

Question 36

What types of HPV are linked to cervical cancer

Answer 36

16 and 18

Question 37

What is the major route of HIV transmission in undeveloped countries

Answer 37

Heterosexual and vertical transmission

Question 38

What is the major route of HIV transmission in developed countries

Answer 38

Homosexual