Chlamydia

Question 1

what are the treatment options for urogenital CT infection in pregnancy?

Answer 1

1. Azithromycin 1g stat, 500mg OD for next 2 days
2. erythromycin 500mg BD for 14 days
3. erythromycin 500mg QDS for 7 days
4. amoxicillin 500mg TDS for 7 days

Question 2

What serotypes of chlamydia cause urogenital infection?

Answer 2

Answer: Serotypes D-K

Question 3

What serotypes of chlamydia cause LGV

Answer 3

serotypes L1, L2 and L3
L2b most commonly causes LGV

L2b most commonly

Question 4

Name three risk factors for developing a chlamydia urogenital infection

Answer 4

1. age <25 years
2. new sexual partner
3. more than one sexual partner

Question 5

What is the concordance rates in couples where one of the partners tests positive for chlamydia?

Answer 5

answer: 75%

Question 6

Name three sites where chlamydia can be found

Answer 6

1. urogenital
2. pharyngeal
3. rectal
4. conjunctiva

Question 7

What percentage of chlamydia infections can resolve spontaneously within 12 months from initial diagnosis?

Answer 7

answer: up to 50%

Question 8

List the common symptoms that women can present with indicative of chlamydia urogenital infection

Answer 8

Symptoms include:-

1. . unusual/ increase in vaginal discharge
2. PCB +/- IMB
3. dysuria
4. symptoms associated with PID (lower pelvic pain, dyspareunia)

note .. the majority of CT infections are asymptomatic

Question 9

What are the signs on examination suggestive of chlamydia urogenital infection in women

Answer 9

1. mucopurulent cervicitis +/- contact bleeding

2. signs of PID - lower pelvic pain, CME on bimanual examination

Question 10

What are the symptoms of urogenital chlamydia infection in men?

Answer 10

1. urethral discharge

2. dysuria

Question 11

what is the main sign in men associated with chlamydia infection

Answer 11

majority are asymptomatic but if symptoms present - clear/milky coloured urethral discharge

Question 12

How do extra-genital chlamydial infections present specifically pharyngeal, rectal and conjunctival

Answer 12

1. pharyngeal - usually asymptomatic
2. rectal - usually asymptomatic, rectal discharge can be present
3. conjunctiva - unilateral low grade irritation

Question 13

List the complications of chlamydia infection in men and women

Answer 13

Women: 1. PID (endometritis/salpingitis) 2. tubal infertility 3. SARA (<1%) 4. peri-hepatitis (fitz hugh curtis)
men: 1. SARA, 2. epididymo-orchtitis

both: LGV (servers L1 - L3)

Question 14

What are the symptoms associated with LGV?

Answer 14

1. tenesmus (the feeling of needing to pass stool when your bowels are empty)
2. rectal discharge usually bloody
3. diarrhoea or altered bowel habit

note can be asymptomatic!

Question 15

what is the window period for chlamydial testing

Answer 15

2 weeks

Question 16

What percentage of women with untreated chlamydia can go on to develop PID?

Answer 16

up to 16% of women

Question 17

A patient attends sexual health with symptoms of unusual vaginal discharge and IMB. How would you test for chlamydia?

Answer 17

Vulvo-vaginal NAAT CT/GC –> this can be self taken or by the clinician
studies suggest that self taken swabs are more sensitive than clinician taken

Question 18

What is the investigation in men used to diagnose urogenital chlamydia?

Answer 18

first catch urine (FCU) - advise men to hold their urine for 1 hour prior to this test.

Question 19

what is the sensitivity of a vulvo-vaginal NAAT CT/GC swab in women

Answer 19

96-98%

Question 20

Does the sensitivity of extra-genital CT/GC testing increase or decrease compared to sensitivity of urogenital testing

Answer 20

decrease

Question 21

Maria attends clinic for treatment of chlamydia from a self swab taken at her GP surgery (VVS). what other investigations would you want to complete during this consultation?

Answer 21

offer full STI screen including bloods for HIV, STS +/- hep B and C serology dependent upon risk factors
no evidence to swab extra-genital sites in CT infection in women

Question 22

Maria is currently 12 weeks pregnant and CT positive, she has no drug allergies and is not on any other medication. How would you treat Maria?

Answer 22

1. Azithromycin 1g stat, followed by 500mg OD for 2 days
2. TOC at 6 weeks is indicated in pregnancy
3. PN should be initiated at the time of the consultation
4. no sex until her and partner have completed Rx and symptoms resolve

Question 23

Maria is now 18 weeks pregnant. She attended for her TOC at 6 weeks post treatment as advised following treatment with Azithromycin (1g stat, 500mg OD 2 days). Her TOC has come back positive. She has NKDA and the pregnancy has otherwise been uneventful. She denies having had sex since the treatment. How would you manage Maria?

Answer 23

Options:

1. erythromycin 500mg QDS for 7 days
2. erythromycin 500mg BD for 10-14 days
3. amoxicillin 500mg TDS for 7 days

advise no sex for 7 days until her and partner completed Rx, TOC at 6 weeks, inform obstetrics

Question 24

Which antibiotics used in the management of chlamydia are contra-indicated in pregnancy and breast-feeding?

Answer 24

doxycycline and ofloxacin

Question 25

what is the first line treatment option for chlamydia infection

Answer 25

doxycycline 100mg BD for 7 days

Question 26

James is a heterosexual, cis-gender male. he reports urethral discharge for the past 2 weeks and did an online STI screen that has come back positive for chlamydia. He tells you he last had sex 3 weeks ago, how would you manage the partner from 3 weeks ago?

Answer 26

advise them to ring an STI clinic and offer screening and treatment- doxycycline 100md bd 7 days

Question 27

James was treated with azithromycin for urogenital CT, he has not had sex since the treatment and TOC has come back positive. He is allergic to doxycycline and erythromycin how would you treat him?

Answer 27

ofloxacin 200mg BD or 400mg OD for 7 days | no sex for 7 days until him and partner been treated, TOC at 6 weeks

Question 28

what are the indications for CT TOC

Answer 28

pregnancy rectal CT peristent symptoms despite RX when compliance is suspected to be low. all patients aged under 25 years should be retested for CT at 3-6months idealy

Question 29

What percentage of patients who test positive for chlamydia can be co-infected with Mycoplasma genitalium?

Answer 29

from 3-15%

Question 30

If someone is allergic to doxycycline and azithromycin what are the treatment options for CT?

Answer 30

1. ofloxacin 200mg BD for 7 days or ofloxacin 400mg OD for 7 days 2. ? might be allergic to macrolides though! erythromycin 500mg BD for 10-14 days

Question 31

What is the look back period for PN in: a) symptomatic men urethral infections b) asymptomatic men and women c) symptomatic women

Answer 31

a)urethral symptomatic men - look back period for PN is 4 weeks | b) asymptomatic men and women, symptomatic women look back period is 6 months

Question 32

what are potential complications for babies born to mothers infected with Chlamydia?

Answer 32

Opthalmia neonatrum and pneumonia - opthalmia neonatrum commonly develops within 5-12 days post delivery and pneumonia in first 3 months following delivery test using NAATs - conjunctiva or nasopharynx

Question 33

how would you treat a neonate diagnosed with ophthalmia neonatrum or pneumonia due to chlamydia

Answer 33

erythromycin 50mg/kg/per day divided into four equal doses for 14 days mum needs treatment and PN

Question 34

Describe the microbiology of chlamydia trachomatis

Answer 34

C. Trachomatis is an intracellular obligate bacterial organism

Question 35

how long is the life cycle of chlamydia trachomatis>

Answer 35

48 - 72 hours

Question 36

describe how chlamydia infects a host cell

Answer 36

elementary body binds to receptor of host cell and enters the cell this way. Chlamydia relies on the host cell for ATP (energy). Once the elementary body is inside the host cell (after 6-9 hours) it then changes into a reticulocyte and replicates (R=R). following replication the reticulocytes fuse and then the cell undergoes lysis and kicks out elementary bodies which go on to infect the next host cell and so on. replication lasts for 24-48 hours

Question 37

why should a CT TOC not be performed within the first three weeks of Rx

Answer 37

as can remain positive for 3-5 weeks due to residual CT DNA. what this means is can cause false positives. Ideally don't do CT TOC until 3 weeks after completion of Rx so usually from 4 weeks on wards in Sheffield we do from 6 weeks. If you do it sooner and negative this is fine, but if positive ignore and re-test again after residual period has passed

Question 38

for cis-females which test is more sensitive VVS NAAT or endocervical NAAT or first catch urine

Answer 38

VVS most sensitive --> then ECS --> FCU