Transcript the presentation - IUSTI Marrakesh 2016 :: Home

Exploring the Role of the
Microbiome in Male Genital
Tract Disease
Lisa E. Manhart, PhD
17th IUSTI World Congress - Marrakech
11 May 2016
Disclosures
• Hologic, Inc. – test kits, reagents, equipment,
service on scientific advisory board
• Qiagen, Inc. – service on scientific advisory board
What is the microbiome?
What do we know about the male
genital tract microbiome?
• Which part of the male genital tract?
• Urethra
• Penile Shaft and Coronal Sulcus
• Semen
• Which clinical entities?
• Urethritis
• HIV infection
• Male Infertility
Urethritis
 Most common male STI syndrome 1
 Characterized by:
• Urethral discharge
• Dysuria
• Pruritis
 Definition:
Urethral symptoms, visible discharge and/or ≥5 PMNs/HPF on
Gram stained smear of urethral exudates2
(2015 update to CDC STD Treatment Guidelines2 recommends lower
cutpoint of ≥2 PMNs/HPF)
1CDC
STD Surveillance 2001;2Martin, STD 2008; 2CDC STD Treatment Guidelines
Urethritis: Consequences
 Clinical sequelae rare
• Epididymitis (1-2%) 1
• Urethral stricture (0.6%) 2
 Increased risk of HIV shedding3
• Seminal HIV RNA decreases after
successful treatment of urethritis
 Transmission of pathogens to sex
partners
1Martin,
STD 2008; 2Santucci, J Urol 2007; 3Cohen, Lancet 1997
Etiology of NGU
 Chlamydia trachomatis
considered major cause of
NGU, but up to half of NGU
cases have no identified
etiology1
CT
None
23.1%
38.5%
MG
UU
 ~40% men with NGU in
PHSKC STD Clinic had no
detected pathogen2
23.4%
TV
1.8%
1Martin,
13.2%
CT
MG
UU
TV
None
STD 2008; 2Manhart, CID 2013
Broad Range 16S rRNA Gene PCR
 Regular PCR targets a known sequence of the bacterial chromosome
• Specific PCR test for each bacterium
 Broad range PCR targets known conserved sequences that bracket
regions of the bacterial chromosome that are unique to each bacterium
• Match unique sequences with database to identify bacteria
• Identify all the bacteria present in an anatomic site
Unique sequence
Known “conserved sequences”
16S
rRNA
gene
Bacterial Vaginosis (BV)
 Most common female reproductive tract condition
• 29.9% prevalence in women age 14-49 participating in NHANES1
 Several recently identified bacteria are highly predictive of
BV; more common in women with cervicitis2, 3
Bacterium
BVAB1
BV2
AOR (95% CI)
19.0 (2.2 – 910.7)
More common in women
with cervicitis3
-
BVAB2
106.1 (14.3 – 4755.1)
++
BVAB3
21.9 (2.5 – 1056.4)
++
Atopobium spp
95.0 (14.5 – ∞ )
++
Egerthella-like spp
103.8 (13.5 – 4812.8)
Leptotrichia spp
330.6 (23.1 – ∞ )
++
Megasphaera α
134.4 (16.6 – 6509.8)
++
1Koumans
-
STD 2007; 2Fredricks NEJM 2005; 3Gorgos, ISSTDR 2009
BVABs and NGU
Men With (n=157) & Without Urethritis(n=102)
18
OR = 2.9 (1.1-7.4)
16
15.3
14
Percent
12
10
8
8.3
7.8
5.9
6
4.5
4
2
0
1
Atopobium
BVAB-2
Cases
1.3
0.6 0
0
BVAB-3
Lepto/Sneath
Megasph
Controls
Manhart et al., Sex Transm Dis 2013;40(12):944-9
Etiologies of NGU
None
32.5%
Lepto/Sneath
6.0%
CT
23.1%
CT
MG
UU
MG
13.2%
UU
23.4%
TV
Lepto/Sneath
None
TV
1.8%
Manhart et al., Sex Transm Dis 2013;40(12):944-9
Urine Microbiome in 19 Asymptomatic
Men Using Broad Range PCR
• 7 bacterial phyla detected
• Domain
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species
Nelson D PLoS One 2010;5(11)e14166
Urine Microbiome in Asymptomatic
Men
Top 5 (rank abundance)
1. L. iners (12.6%)
2. Sneathia sp. (5.7%)
3. Gemella sp. (5.5%)
4. Aerococcus sp. (52%)
25 most common
bacterial genera
5. Corynebacteria sp. (4.6%)
Nelson D PLoS One 2010;5(11)e14166
Men with Asymptomatic STI have
Different Urine Microbiomes
Nelson D PLoS One 2010;5(11)e14166
Implications
• Does a characteristic microbiome enhance
susceptibility to STI?
OR
• Does acquisition of STI change the microbiome?
Microbiota of Women with BV
Srinivasan PLoS One 2012;7(6):e37818
Heterosexual men with NGU have less
diverse urethral microbiota
Median diversity index
Cases
Controls
p
1.145
2.229
0.03
Penile Microbiota & BV in Partners
Penile microbiota of 165 HIV- uncircumcised men yielded 7
community state types (CST) using hierarchical clustering
Low Density
High Density
Liu et al. mBio 2015;6(3):e00589-15
Penile Microbiota & BV in Partners
• High density CSTs (4 – 7) associated with having a partner with BV
• PRR = 1.55; 95% CI 1.07 – 2.24 (relative to CST 1-3)
• High prevalence of BVABs in men with CSTs 4 – 7
• Among men with CST 4 – 7, those with a partner with BV had increased
bacterial density
CST 4-7
Liu et al. mBio 2015;6(3):e00589-15
Circumcision and the Penis
Microbiome
• Circumcision was associated with a decrease in
anaerobic bacteria
Pre-circumcision
Mean Abundance (SD)
Post-circumcision
Mean Abundance (SD)
Wilcoxon
Signed-Rank
Test
236.4 (119.1)
466.8 (65.6)
p=0.62
Anaerobic
71.8 (69.6)
4.8 (6.2)
p=0.014
Facultative anaerobic
22.8 (19.8)
78.9 (53.4)
p=0.006
Bacterial Family Oxygen
Requirement
Aerobic
• Circumcision also associated with decreased
diversity of bacterial species
Price et al. PLoS One 2010;5(1):e8422
Semen Microbiome & Infertility
• More diverse than vaginal
microbiota (90 vs. 12 unique
phylotypes), but lower bacterial
concentrations1
• 6 clusters identified in fertile and
infertile men2
• Clusters not associated with fertility
• Only Anaerococcus associated with reduced
sperm quality, p=0.0012
• More bacteria than sperm
1Mandar
et al, Res Microbiol 2015;166(5):440-447; 2Hou et al, Fert Steril 2013;100(5):1261-1269
Semen Microbiome and Cytokines
• HIV-uninfected men: no relationship between
semen bacterial load and cytokine levels
• HIV-infected men:
• For each 10% increase in semen bacterial load, 2%
increase in
•
•
•
•
•
•
•
IL-6
IL-17
Component 1
IP-10
IL1b (3% increase) Component 2
MIG
Component 3
IL-10
TNF-α
Correlated
with HIV
viral load
Liu et al. PLoS Pathog 2014;10(7):e1004262
What do we know about the male
genital tract microbiome?
• Urine microbiome in men with and without STI differs but…. which
came first?
• Urethritis may be characterized by lower diversity of bacterial species
• Anaerobes & overall species diversity reduced in circumcised men
• Female partners with BV associated with a higher density of bacteria
detected on penis and BVABs
• Higher bacterial load in semen associated with increased proinflammatory cytokines in HIV+ men
• Most data on male genital tract microbiome is cross-sectional
• Longitudinal studies are needed to determine causality
THANKS!
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David Fredricks
Sujatha Srinivasan
Tina Fiedler
Matt Munch
Congzhou Liu
M. Sylvan Lowens
Jennifer Morgan
Matthew Golden
Julie Dombrowski
Laura Chambers
Tashina Robinson
Sarah Romano
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Jeanne Marrazzo
Anna Wald
Jim Hughes
Sean Proll
Patricia Totten
Olusegun Soge
• PHSKC STD Clinic
• Hologic, Inc. donated test kits
and reagents
• NIH/NIAID
• 1R01AI110666-01
• 1U19AI113173-01