3. Sexually transmitted diseases

Question 1

What are the main issues that concern STIs as a whole?

Answer 1

Many clinical presentations and many are asymptomatic
Different risks in different populations
Some are incurable 
There is always more than one patient - vertical transmission or partner notification 
Confidentiality 
High rates of re-infection 
Might be a life long infection 
Stigma and psychological morbidity 
Becoming increasingly difficult to treat

Question 2

What factors lead to an increased risk of STIs?

Answer 2

Age 
Sexual partner
Sexual practice 
Lack of condom usage
Ethnicity 
Area of resistance

Question 3

What is the most common STI in England and how has this differed?

Answer 3

Chlamydia but the rates have stabilised due to a national Chlamydia screening programme

Question 4

In what group of people is the STI rate the highest?

Answer 4

Heterosexuals under the age of 25

Also in men who have sex with other men

Question 5

Is Gonorrhoea more common in men or women?

Answer 5

Men

Question 6

Is syphilis more common in men or women?

Answer 6

Men

Question 7

What is the pathogen responsible for chlamydia infection?

Answer 7

Chlamydia trachomatis - intracellular pathogen

Question 8

What are the clinical presentations of chlamydia?

Answer 8

Asymptomatic infections are common
Some strains cause eye infections which can lead to blindness
Men - pain when passing urine, discharge from the penis, infection of prostate gland
Women - can cause pelvic inflammatory disease, pain when passing urine, vaginal discharge

Reactive arthritis - patients may present with joint symptoms or a rash

Question 9

What is the impact of chlamydia on fertility and on a neonate?

Answer 9

Chlamydia can be carried for a long time without you realising as it is often asymptomatic
Associated with a very high risk of infertility in both men and women
If infected as a neonate from the mother - baby can develop conjunctivitis and pneumonia

Question 10

How might chlamydia present in homosexual men?

Answer 10

Serovars L1-3 are the most common in men who have sex with men
Rectal bleeding
Change in bowel habit
Swollen lymph nodes around the inguinal/genital region

Question 11

How is chlamydia treated?

Answer 11

With tetracyclines: azithromycin, doxycycline

Question 12

What is the pathogen responsible for genital warts

Answer 12

Human papilloma virus

Second most common STI

Question 13

What are the clinical presentations of genital warts?

Answer 13

90% of people with this infection are asymptomatic

The warts can otherwise present in multiple sites but mainly the genitals

Question 14

What are the risks associated with a HPV infection?

Answer 14

Some of these strains are associated with carcinoma - 16, 18, 31, 33
There is an increasing incidence in ano-genital and oro-pharyngeal carcinoma i.e. increasing cancers associated with HPV

Question 15

What is the treatment for genital warts?

Answer 15

Topical podoophyllotoxon, imiquimod
Cryrotherapy - can freeze the warts off

There is currently a vaccination in place - hoping that this will result in a decreasing incidence over time

Question 16

What is the pathogen responsible for gonorrhoea?

Answer 16

Neisseria gonorrhoea

Question 17

How does gonorrhoea present in patients?

Answer 17

Males - urethritis, proctitis (inflammation of rectum and anus), sore throat, epididymitis, prostatitis
Females - cervicitis, PID, pain and discharge from the ureter, discharge during sex

Can also lead to infertility

Question 18

How does gonorrhoea present in neonates?

Answer 18

Conjunctivitis: eye infection, sticky eyes - this can lead to blindness if untreated

Question 19

What is the treatment for gonorrhoea?

What is the problem with this?

Answer 19

Current management is drug Ceftriaxone

BUT there is increasing resistance to this so must make sure that the patient is fully treated before discharging them

Question 20

What are the pathogens responsible for herpes infection?

Answer 20

Herpes simplex virus 1 and 2

HSV-1 oral and HSV-2 genital but now understood that they both contribute to both

Question 21

What are the different stages of a Herpes infection?

Answer 21

Primary infection
Stage of latency - the DNA virus sits and does nothing in the trigeminal or sacral nerve ganglia
Can then have a reactivation of the virus

Question 22

What are the clinical presentations of Herpes?

Answer 22

The primary infection is very asymptomatic - may present with painful ulcers and blisters
No symptoms during the latent stage
When reactivated, may either present with symptoms or may be asymptomatic

May feel unwell - have a fever or a headache
HSV 1 - commonly known as a cold sore
HSV 2 - commonly known a a genital wart

Question 23

What it the treatment for herpes?

Answer 23

Herpes is not curable - it will stay forever within (like chicken pox) and can reactivate
Management includes aciclovir, famciclovir, valaciclovir

Question 24

What is the pathogen responsible for syphilis?

Answer 24

Treponema Pallidum

Question 25

What are the different types and stages of syphilis?

Answer 25

Primary
Secondary - occurs 4 to 10 weeks after primary infection
Latent
Tertiary - occurs 3 to 15 years after primary infection
Congenital

Question 26

How is syphilis diagnosed?

Answer 26

Via serology

Question 27

What are the clinical presentations of primary syphilis?

Answer 27

Primary chancre - single, usually painless ulcer in the mouth, anus, vulva, vagina, penis - heals up after a few weeks and goes away on its own

Highly infectious at this stage

Question 28

What are the clinical presentations of secondary syphilis?

Answer 28

Rash - affects the palms of the hand and the soles of the feet (no other infection causes this! big clue that this is syphilis!)
Fever
Condyloma lata (flesh-like warts

Question 29

Describe the current epidemiology of HIV and why it is changing?

Answer 29

Decreasing incidence
Increasing prevalence

Have gotten better at preventing the disease but ageing population with sufferers of the disease

Question 30

How does HIV cause disease in the cells of the body?

Answer 30

HIV infects CD4+ cells (T-helper), macrophages and dendritic cells and there is increased viral replication
This acute primary infection leads to a massive loss of CD4+ cells
Chronic HIV infection is associated with on-going loss of CD4+ cells, a decline in immune function and progressive immunosuppression

Question 31

Why can HIV show as a false negative in serology?

Answer 31

The HIV antibody can take up to 3 months to become positive

Question 32

What are the clinical presentations of a primary HIV1 infection/

Answer 32

Headache
Pharyngitis 
Oral/genital ulceration
Nausea
Rash
Fever and fatigue
Weight loss/night sweats

Question 33

What is the aim of the antiretroviral therapy in HIV?

Answer 33

Suppression of the HIV replication
CD4+ count recovery
Immune reconstitution
Long term reduced risk of morbidity and mortality

Question 34

How is HIV currently treated?

Answer 34

HAART - highly active antiretroviral therapy
There are 6 classes of antiretroviral drugs
Must always treat with a combination of antiretroviral drugs - combine at least 3 drugs from at least 2 classes
The treatment is lifelong

Question 35

What are the adverse effects associated with HAART?

Answer 35

Short term - nausea, vomiting, headache, sleep disturbance
Long term - renal dysfunction, peripheral neuropathy, lactic acidosis
May have adverse drug interactions

Question 36

How is HIV managed in pregnancy?

Answer 36

Must carry out early screening for HIV
Antiretroviral therapy must be administered for the mother - this should be immediate and continued if the CD4 count is low
Elective c-section (vaginal delivery is possible if there is an undetected HIV load)
Antiretroviral therapy for the infant
No breastfeeding