25 - Introduction to STIs

Question 1

name 3 venereal diseases in UK?

Answer 1

syphilis

gonorrhoea

chancroid

Question 2

what organism causes syphilis?

Answer 2

treponema pallidum pallidum

Question 3

what organism causes gonorrhoea?

Answer 3

neisseria gonorhoeae

Question 4

what organism causes chancroid?

Answer 4

haemophilus ducreyi

Question 5

name 3 bacterial STIs in the UK?

Answer 5

chlamydia trachomatis

klebsiella granulomatis

mycoplasma genitalium

Question 6

name 3 viral STIs in the UK?

Answer 6

HSV

HIV

HPV

Molluscum Contagiosum

Question 7

name 3 parasitic STIs in the UK?

Answer 7

Pthirus pubis

Sarcoptes scabei

Trichomonas vaginalis

Question 8

define Commensal micro-organism?

Answer 8

micro-organism that derives food or other benefits from another organism without hurting or helping it

Question 9

define Pathogen?

Answer 9

micro-organism that can cause disease

Question 10

define Infection?

Answer 10

The invasion of all or part of the body by a micro-organism

Question 11

define Sexually transmissible organism?

Answer 11

A virus, bacteria, protozoan, insect or arthropod which can be spread by sexual contact

Question 12

define Sexually transmitted infection (STI)?

Answer 12

infection by a pathogen which is sexually transmissible and which is unlikely to be transmitted by non-sexual means

Question 13

define Sexually transmitted disease (STD)?

Answer 13

disorder of structure or function caused by a sexually transmitted pathogen

Question 14

name 4 diseases which are not classed as STI in UK but may be considered as such elsewhere?

Answer 14

Mycoplasma hominis

Ureaplasma urealyticum

Bacterial vaginosis

Genital candidosis

Question 15

name 2 STI pathogens which are not classed as STI in UK but may be considered as such elsewhere?

Answer 15

Sars-Cov-2

Zika

Ebola

Question 16

what does the type of STI contracted depend on?

Answer 16

the level of sexual contact

Question 17

list the following from lowest risk of catching STI to highest -

group sex

fellatio

anal sex

mutual masturbation

cunnilingus

vaginal sex

Answer 17

LOW RISK

mutual masturbation

fellatio

cunnilingus

vaginal sex

anal sex

group sex

HIGH RISK

Question 18

describe 4 STIs transmitted by skin only contact?

Answer 18

pubic lice (Pthirus pubis)

Scabies (Sarcoptes scabeii)

Warts (human papilloma virus types 6 &11)

Herpes (Herpes Simplex Virus types 1 & 2)

Question 19

name an STI which poses a high risk of transmission during group sex?

Answer 19

Hep C

Question 20

name 5 reasons which highlight the importance of STIs?

Answer 20

cause morbidity

cause mortality

unpleasant symptoms

psychological distress

very costly and time-consuming to treat

Question 21

name 5 systemic symptoms related to STIs?

Answer 21

Fever

Rash

Lymphadenopathy

Malaise

Arthralgia and arthritis

Question 22

give an example of a late complication if chlamydia is left untreated?

Answer 22

infertility in females

Question 23

give an example of a late complication if HPV is left untreated?

Answer 23

cervical cancer

Question 24

give an example of a late complication if syphilis is left untreated?

Answer 24

adverse pregnancy outcomes

Question 25

give 2 possible reasons to why trends in STI diagnoses change over time?

Answer 25

1 - true difference in no of cases 2 - change in diagnoses but no real change in difference of no of cases

Question 26

what equation is used for calculating the true difference in the no of cases?

Answer 26

R0=BcD R0 = reproductive number (average number of infections produced) B = likelihood of transmission per encounter c = rate of acquiring new partners D = duration of infectivity

Question 27

describe the results of R0=BcD if R0 > 1 or if R0 < 1?

Answer 27

R0 > 1 = epidemic is sustained R0 < 1 = epidemic reduces

Question 28

what is the best way of ensuring no transmission of HPV? (B)

Answer 28

vaccination of unaffected patients

Question 29

describe 5 changes of rate of new partners (c) in current times?

Answer 29

increased no of partners increased no of concurrent partners increased no of people having anal sex increased no of men having sex with men increased condom use

Question 30

describe an example which supports the theory that there is a change in diagnoses but no real change in difference of no of cases for STIs?

Answer 30

there is a greater awareness of STIs - therefore more tests being carried out - therefore more cases found

Question 31

describe the theory of cores and assortative mixing in explaining why some STIs are more prevalent in certain groups?

Answer 31

cores and assortative mixing - people tend to have sex with people who are similar to them therefore - infection is reinforced within a small group

Question 32

describe the theory of chains and random mixing in explaining why some STIs are more prevalent in certain groups?

Answer 32

e.g. men who have sex with woman - this is a big core of people therefore - spreads more widely but with decreased prevalence

Question 33

describe 4 pillars of taking a good STI history?

Answer 33

1 - thorough history 2 - health promotion 3 - partner notification (if STI confirmed) 4 - HIV test (if STI confirmed)

Question 34

describe 3 components of a general history which would be relevant?

Answer 34

standard (PMH etc.) gynae history direct questions about symptoms

Question 35

give 3 reasons for taking a thorough sexual history?

Answer 35

to determine cause of symptoms to detect high-risk behaviour tracing contacts

Question 36

6 questions which are important to ask men to determine longer-term sexual risks?

Answer 36

Have you ever had sexual contact with another man? Have you ever injected drugs? Sexual contact with: anyone who’s injected drugs/ someone from outside the UK? Medical treatment outside UK? Paid for sex or been paid?

Question 37

describe 2 ways of partner notification?

Answer 37

Patient tells contacts “client referral” NHS tells contact “provider referral”

Question 38

if someone has a confirmed case of STI, what should they be tested for?

Answer 38

HIV

Question 39

5 examples of health promotion?

Answer 39

use of condoms inform that oral sex also carries a risk of STIs address hazardous drug/ alcohol use vaccination HIV pre-exposure prophylaxis