Nav: Home

Chlamydia in testicular tissue linked to male infertility

October 09, 2019

The potential impact of undiagnosed sexually transmitted chlamydia infection on men's fertility has been highlighted in a study led by Queensland University of Technology (QUT), which for the first time found chlamydia in the testicular tissue biopsies of infertile men whose infertility had no identified cause.

The researchers also found antibodies specific to the bacteria responsible, Chlamydia trachomatis, in the blood of 12 of 18 donors of the fresh testicular biopsies, indicating the men had been exposed to the bacteria -- yet none of the men reported symptoms of infection or being previously diagnosed with chlamydia or any other sexually-transmitted infection (STI).

The study, in collaboration with Monash IVF Group, Hudson Institute of Medical Research, Monash Health, and Queensland Fertility Group, has been published in the journal Human Reproduction.

Key findings:
  • Men whose tissue was tested were moderately to severely infertile, producing no or little sperm, and the majority had no defined cause of their infertility.
  • Chlamydia was found in 45.3 per cent of fixed testicular biopsies (43 of 95 men), obtained from the Monash Health Anatomical Pathology Department. All men in this group had no defined cause of infertility.
  • Chlamydia was also found in 16.7 per cent of fresh testicular biopsies (3 of 18 men), obtained during patient sperm recovery procedures by the Monash IVF Group and Queensland Fertility Group. These 3 men, and another 10 in the group, had no identified cause for their infertility.
  • In 12 of the 18 men providing the fresh biopsies (66.7 per cent) Chlamydia trachomatis-specific antibodies were found in serum, indicating the men had been exposed to the bacteria - but all were asymptomatic and said they'd not been diagnosed with any STI.
Research leader QUT Professor of Immunology Ken Beagley, from the Institute of Health and Biomedical Innovation, said chlamydia infection in men has not been as widely studied as it has in women, despite similar infection rates.

"Chlamydia infection has been associated with women's infertility but much less is known about its impact on male infertility, particularly if men do not experience symptoms, which is estimated to be in about 50 per cent of cases," he said.

"When people have no symptoms they can unknowingly pass on the infection to sexual partners.

"This is the first reported evidence of chlamydia infection in human testicular tissue, and while it can't be said that chlamydia was the cause of the infertility of the men, it is a significant finding.

"It reveals a high rate of previously unrecognised chlamydia infection and the potential role of infection in the failure of sperm to develop in the testes.

"Animal studies by our group support these human findings. Those studies show that chlamydia infection in male mice establishes a chronic infection in the testes that significantly impairs normal sperm development.

"We believe future studies with male patients should look at how chlamydia infection might cause damage to the male reproductive system and contribute to infertility."

Professor Beagley said testing testicular tissue could also be a useful future screening and diagnostic tool for clinicians and help inform them about treatments to improve reproductive outcomes.

"Normally a diagnosis of chlamydia infection is performed with a urine sample, but this may not always pick up the infection in men," he said.

"In our study, two of the three patients whose fresh biopsies were positive for chlamydia were urine-negative for the bacteria. For the third patient we weren't able to obtain a urine result.

"It indicates that infection may not shed into the urinary system, or do so only intermittently."

Monash IVF Group male fertility specialist and study co-author, Professor Robert McLachlan, said for the majority of men with poor quality sperm, a cause is not apparent.

"We know certain contributors, like the toxic effect of chemotherapy drugs, but for many men there is nothing remarkable in their sexual or medical history that could account for their fertility issues," he said.

"Understanding a cause is the first step in being able to do something about it.

"Chlamydia infection in men is something we think needs further investigation. If it is a potential cause or exacerbating factor, it gives us a target, something to aim at.

"If it does have a role, then we need to understand what that role is, what's the best way to treat it, can treatment repair damage and improve sperm count, and also how we can prevent it."
-end-
The team's research was funded by an Australian National Health and Medical Research Council grant.

The study paper, Detection of chlamydia Infection within human testicular biopsies, can be accessed here: https://academic.oup.com/humrep/advance-article/doi/10.1093/humrep/dez169/5580920

Queensland University of Technology

Related Bacteria Articles:

Bacteria might help other bacteria to tolerate antibiotics better
A new paper by the Dynamical Systems Biology lab at UPF shows that the response by bacteria to antibiotics may depend on other species of bacteria they live with, in such a way that some bacteria may make others more tolerant to antibiotics.
Two-faced bacteria
The gut microbiome, which is a collection of numerous beneficial bacteria species, is key to our overall well-being and good health.
Microcensus in bacteria
Bacillus subtilis can determine proportions of different groups within a mixed population.
Right beneath the skin we all have the same bacteria
In the dermis skin layer, the same bacteria are found across age and gender.
Bacteria must be 'stressed out' to divide
Bacterial cell division is controlled by both enzymatic activity and mechanical forces, which work together to control its timing and location, a new study from EPFL finds.
How bees live with bacteria
More than 90 percent of all bee species are not organized in colonies, but fight their way through life alone.
The bacteria building your baby
Australian researchers have laid to rest a longstanding controversy: is the womb sterile?
Hopping bacteria
Scientists have long known that key models of bacterial movement in real-world conditions are flawed.
Bacteria uses viral weapon against other bacteria
Bacterial cells use both a virus -- traditionally thought to be an enemy -- and a prehistoric viral protein to kill other bacteria that competes with it for food according to an international team of researchers who believe this has potential implications for future infectious disease treatment.
Drug diversity in bacteria
Bacteria produce a cocktail of various bioactive natural products in order to survive in hostile environments with competing (micro)organisms.
More Bacteria News and Bacteria Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Clint Smith
The killing of George Floyd by a police officer has sparked massive protests nationwide. This hour, writer and scholar Clint Smith reflects on this moment, through conversation, letters, and poetry.
Now Playing: Science for the People

#562 Superbug to Bedside
By now we're all good and scared about antibiotic resistance, one of the many things coming to get us all. But there's good news, sort of. News antibiotics are coming out! How do they get tested? What does that kind of a trial look like and how does it happen? Host Bethany Brookeshire talks with Matt McCarthy, author of "Superbugs: The Race to Stop an Epidemic", about the ins and outs of testing a new antibiotic in the hospital.
Now Playing: Radiolab

Dispatch 6: Strange Times
Covid has disrupted the most basic routines of our days and nights. But in the middle of a conversation about how to fight the virus, we find a place impervious to the stalled plans and frenetic demands of the outside world. It's a very different kind of front line, where urgent work means moving slow, and time is marked out in tiny pre-planned steps. Then, on a walk through the woods, we consider how the tempo of our lives affects our minds and discover how the beats of biology shape our bodies. This episode was produced with help from Molly Webster and Tracie Hunte. Support Radiolab today at Radiolab.org/donate.