Microbiology

Question 1

What is bacterial vaginosis?

Answer 1

altered vaginal flora - pH becomes alkaline

Question 2

Why does the vaginal pH change in bacterial vaginosis?

Answer 2

normal vaginal flora (lactobacillus - produces lactic acid) replaced with Gardnerella vaginalis and other anaerobic bacteria

Question 3

How does bacterial vaginosis present?

Answer 3

fishy discharge

Question 4

What can bacteria vaginosis increase the risk of?

Answer 4

preterm labour
intra amniotic infection in preg
susceptibility to HIV
2nd trimester miscarriage

Question 5

How is bacterial vaginosis diagnosed?

Answer 5

mixed with 10% potassium hydroxide on a slide - whiff of ammonia
wet mount microscopy - clue cells (epithelial cells coated with coccobacilli)

Question 6

What is the treatment of bacterial vaginosis?

Answer 6

metronidazole 7 days

Question 7

What causes thrush?

Answer 7

candida albicans

Question 8

What are risk factors for developing thrush?

Answer 8

pregnancy
diabetes
immunodeficiency
antibiotics

Question 9

How does thrush present?

Answer 9

red, fissured, sore vulva and vaina
cottage cheese discharge
itch

Question 10

How is thrush diagnosed?

Answer 10

clinical diagnosis

HVS, microscopy and culture

Question 11

How is thrush treated?

Answer 11

topical - clotrimazole

oral - fluconazole

Question 12

What is the most common bacterial STI in the UK?

Answer 12

chlamydia

Question 13

what causes chlamydia?

Answer 13

Chlamydia trachomatis

Question 14

Where does chlamydia infect?

Answer 14

urethra
rectum 
throat
eyes 
endocervix

Question 15

Why does chlamydia stain with gram?

Answer 15

no peptidoglycan in cell wall

Question 16

What are the 3 serological groupings of chlamydia?

Answer 16

A-C: trachoma (eye) - not an STI
D-K: genital infections
L1-L3: lymphogranuloma venereum (rectal pain, discharge, bleeding, MSM)

Question 17

What is the presentation of chlamydia in females?

Answer 17

usually asymptomatic
mucopurulent cervicitis
lower abdo pain
postcoital/intermenstrual bleeding, dyspareunia

Question 18

What is the presentation of chlamydia in males?

Answer 18

asymptomatic 
dysuria 
urethritis 
proctitis (LGV)
urethral discharge

Question 19

What are the complication of chlamydia infection?

Answer 19

reactive arthritis 
PID 
tubal damage 
chronic pelvic pain 
transmission to neonate - pneumonia, conjunctivitis 
Fitz-Hugh-Curtis syndrome

Question 20

How is chlamydia diagnosed?

Answer 20

males: first void urine sample (add rectal swab if receptive anal sex)
females: HVS

for NAATs/ PCR

Question 21

What is the treatment of chlamydia?

Answer 21

aczithromycin - 1g oral dose (uncomplicated)

Question 22

What causes gonorrhoea?

Answer 22

Neisseria gonorrhoea

gram negative diplococcus

Question 23

Where can gonorrhoea infect?

Answer 23

urethra
rectum 
eyes
throat
endocervix

Question 24

How does gonorrhoea present?

Answer 24

males: urethral discharge, dysuria, ?asymptomatic, rectal and pharyngeal symptoms
females: asymptomatic, dysuria, pelvic pain, altered vaginal discharge

Question 25

How is gonorrhoea diagnosed?

Answer 25

same as chlamydia men: first void urine sample + rectal swab/pharyngeal swab women: HVS NAAT/PCR

Question 26

How is gonorrhoea treated?

Answer 26

IM ceftriaxone | oral azithromycin

Question 27

What organism causes syphilis?

Answer 27

Treponema pallidum | spirochaete

Question 28

Does Treponema pallidum stain with gram?

Answer 28

no

Question 29

What is the primary stage of syphilis?

Answer 29

chancre (painless ulcer, heals without treatment)

Question 30

What is the secondary stage of syphilis?

Answer 30

flu like symptoms generalised rash snail track mouth ulcers

Question 31

What is the latent stage of syphilis?

Answer 31

early latent stage: no symptoms | late latent stage: near and cardiac complications

Question 32

What is the treatment of syphilis?

Answer 32

penicillin benzathine

Question 33

How is syphilis diagnosed?

Answer 33

PCR and serological tests | dark ground microscopy

Question 34

What is trochomonas vaginalis?

Answer 34

single celled protozoal parasite | sexually transmitted

Question 35

How does trichomonas vaginalis present?

Answer 35

thin, bubbly, fish smelling discharge

Question 36

How is trichomonas vaginalis diagnosed?

Answer 36

HVS for microscopy

Question 37

How is trichomonas vaginalis treated?

Answer 37

oral metronidazole

Question 38

How are pubic lice treated?

Answer 38

malathion lotion

Question 39

What type of herpes simplex is sexually transmitted?

Answer 39

``` type 2 (type 1 - coldsores) ```

Question 40

How does herpes simplex present?

Answer 40

very painful blisters dysuria discharge

Question 41

How is HSV diagnosed?

Answer 41

swab of deroofed blister for PCR

Question 42

How is HSV treated?

Answer 42

``` analgesia acyclovir (shortens symptoms and infectivity) ```

Question 43

What are the high risk HPVs?

Answer 43

16 and 18 (CIN)