1. Rectal chlamydia infection in women Have we been missing the point?
Dr Harriet Wallace
On behalf of
M Loftus-Keeling, H Ward, C Hulme, M Wilcox, JD Wilson
BASHH conference - Oxford 2016

2. Introduction
BASHH/MEDFASH Standards 2014

3. Introduction
BASHH/MEDFASH Standards 2014

4. Introduction
Using only vulvovaginal NAATs for chlamydia (CT) and gonorrhoea (NG) in women may miss infection at extragenital sites1
Increased case finding after introduction of rectal screening UK sites2
Identifying rectal CT infection may affect the management required3
Recent Swedish study identified a rectal CT prevalence in women of 9.1% by routine screening4
Trebach J et al Sex Trans Dis 2015;42(5):233-9
Garner et al. Int J STD&AIDS 2015;26(7):462-6
Kong FYS et al J Antimicrob Chemother 2015;70(5):
Anersson N et al Int J STD&AIDS online 2016 doi: /

5. Methods ‘SYSTEMATIC’ trial
Inclusion criteria: 16yrs+, no antibiotics in the last 4 wks, no rectal symptoms, willing for extragenital tests
NAATs from pharyngeal and rectal sites for chlamydia (CT) and gonorrhoea (NG) using Aptima Combo 2: (randomised order)
1 x clinician-taken sample
2 x self samples (1 analysed individually, 1 pooled into single collection pot together with VVS NAATs)
Patient infected status: at least 2 positive confirmed samples
Site infected status: PIS positive plus at least 1 positive from site

6. Results 1191 women recruited Median age 23 years (16-71)
Ethnicity: 83% white British/white other
38% had a previous STI
15% were a contact of infection (9.5% chlamydia contacts)
31% attended with symptoms consistent with a urogenital infection
discharge, dysuria, lower abdo pain, deep dyspareunia, IMB, PCB

7. Results: Sexual history
1190 (99.9%) reported ever having vaginal sex
1142 (95.9%) ever given oral sex to a male partner
548 (46%) ever had receptive anal sex

8. Results: Chlamydia (CT) infection
227 women CT positive at any site (VVS, Rectal, Pharynx), overall prevalence 19.1%
Prevalence by site:
Rectal 17.5% (n=209) VVS 16.5% (n=197) Pharyngeal 4.7% (n=56)
Site
Number of cases CT positive
Rectal & VVS
146
Rectal & VVS & Pharyngeal 41
Rectal only 17
VVS only 8
Pharyngeal only
Rectal & Pharyngeal 5
VVS & Pharyngeal 2

9. Results: Chlamydia (CT) infection
227 women CT positive at any site (VVS, Rectal, Pharynx), overall prevalence 19.1%
Prevalence by site:
Rectal 17.5% (n=209) VVS 16.5% (n=197) Pharyngeal 4.7% (n=56)
Site
Number of cases CT positive
Rectal & VVS
146
Rectal & VVS & Pharyngeal 41
Rectal only 17
VVS only 8
Pharyngeal only
Rectal & Pharyngeal 5
VVS & Pharyngeal 2
41% reported no previous anal sex

10. Comparison of those women with rectal Chlamydia vs those without
With rectal CT (n=209)
Without rectal CT (n=982)
p value

11. Comparison of those women with rectal Chlamydia vs those without
With rectal CT (n=209)
Without rectal CT (n=982)
p value
Median age (years)
21 (IQR 19-24)
24 (IQR 20-28)
p=0.026 (Chi2)

12. Comparison of those women with rectal Chlamydia vs those without
With rectal CT (n=209)
Without rectal CT (n=982)
p value
Median age (years)
21 (IQR 19-24)
24 (IQR 20-28)
0.026 (Chi2)
Contact of STI
82 (39%)
96 (10%)
<0.001 (Chi2)

13. Comparison of those women with rectal Chlamydia vs those without
With rectal CT (n=209)
Without rectal CT (n=982)
p value
Median age (years)
21 (IQR 19-24)
24 (IQR 20-28)
0.026 (Chi2)
Contact of STI
82 (39%)
96 (10%)
<0.001 (Chi2)
Contact of CT
78 (37%)
38 (4%)

14. Comparison of those women with rectal Chlamydia vs those without
With rectal CT (n=209)
Without rectal CT (n=982)
p value
Median age (years)
21 (IQR 19-24)
24 (IQR 20-28)
0.026 (Chi2)
Contact of STI
82 (39%)
96 (10%)
<0.001 (Chi2)
Contact of CT
78 (37%)
38 (4%)
Contact of GC only
2 (1%)
27 (2.8%)
0.212 (Fisher’s Exact)

15. Comparison of those women with rectal Chlamydia vs those without
With rectal CT (n=209)
Without rectal CT (n=982)
p value
Median age (years)
21 (IQR 19-24)
24 (IQR 20-28)
0.026 (Chi2)
Contact of STI
82 (39%)
96 (10%)
<0.001 (Chi2)
Contact of CT
78 (37%)
38 (4%)
Contact of GC only
2 (1%)
27 (2.8%)
0.212 (Fisher’s Exact)
History of a previous STI
88 (42%)
368 (37%)
0.211 (Chi2)

16. Comparison of those women with rectal Chlamydia vs those without
With rectal CT (n=209)
Without rectal CT (n=982)
p value
Median age (years)
21 (IQR 19-24)
24 (IQR 20-28)
0.026 (Chi2)
Contact of STI
82 (39%)
96 (10%)
<0.001 (Chi2)
Contact of CT
78 (37%)
38 (4%)
Contact of GC only
(1%)
27 (2.8%)
0.212 (Fisher’s Exact)
History of a previous STI
88 (42%)
368 (37%)
0.211 (Chi2)
Symptoms of urogenital infection
82 (40%)
294 (30%)
0.922(Chi2)

17. Comparison of those women with rectal Chlamydia infection vs those without Sexual history
With rectal CT (total group =209)
Without rectal CT (total group =982)
p value
Ever had anal sex
106/209 (51%)
442/982 (45%)
0.133 (Chi2)

18. Comparison of those women with rectal Chlamydia infection vs those without Sexual history
With rectal CT (total group =209)
Without rectal CT (total group =982)
p value
Ever had anal sex
106/209 (51%)
442/982 (45%)
0.133 (Chi2)
Condom use anal sex ‘never’
75/102 (74%)
4 missing
266/383 (69%)
59 missing
0.415 (Chi2)
Condom use anal sex ‘always’
18/102 (18%)
82/383 (21%)
0.404 (Chi2)

19. Comparison of those women with rectal Chlamydia infection vs those without Sexual history
With rectal CT (n=209)
Without rectal CT (n=982)
p value
Condom use vaginal sex ‘never’
106 (51%)
442/976 (45%)
6 missing
0.153 (Chi2)

20. Comparison of those women with rectal Chlamydia infection vs those without Sexual history
With rectal CT (n=209)
Without rectal CT (n=982)
p value
Condom use vaginal sex ‘never’
106 (51%)
442/976 (45%)
6 missing
0.153 (Chi2)
Condom use vaginal sex ‘always’
12 (6%)
113 /976 (12%)
0.013 (Chi2)

21. Conclusions
CT prevalence higher on rectal NAATs then VVS in this population (rectal 17.5% vs VVS 16.5%)
NOT testing for rectal CT infection in this group
would have missed 10% of the total chlamydia infections (sole rectal or rectal/ph infection only)
possible incomplete management in 95% of those who tested positive for CT on VVS who were also rectally infected

22. Conclusions Rectal CT infection was NOT significantly associated with:
Self report of previous anal sex
Self report of a previous STI
Presentation with symptoms of urogenital infection
Is it time for a discussion on universal rectal screening in women?

23. harriet.wallace@nhs.net Acknowledgements
NHS National Institute Health Research, Research for Patient Benefit Programme
This presentation presents independent research funded by the National Institute for Health Research (NIHR) under its Research for Patient Benefit (RfPB) Programme (Grant Reference Number PB-PG ). The views expressed are those of the authors and not necessarily those of the NHS, the NIHR or the Department of Health.
Hologic for providing the extra swabs for the pooled samples and the sample kits and reagents for the environmental samples
All the staff and patients at Leeds Sexual Health