If you're a gay man and think you have lactose intolerance, gluten sensitivity, irritable bowel, or are just unlucky read this

If You’re an MSM Experiencing GI Symptoms

If you are a Man that has sex with men (MSM) and think you have Lactose Intolerance, Gluten Sensitivity/Gluten Allergy, or Irritable Bowel Syndrome, You may want to read this.

Many gay men with intestinal parasitic infections are misdiagnosed and can live for years thinking they have one of the above when in reality what they have is an infection that could easily be treated if known about.

Why does this happen? Well, straight people living in developed countries are at very low risk for parasitic infections, so medical providers who don't specialize in the care of MSM frequently aren't that familiar with them, don't know how to test for them properly, and tend not to expect them. Lastly, some of the testing for intestinal parasites isn't very sensitive, meaning one test for parasites coming back negative may not be enough to ensure you aren't infected. Yet, many times only one test is done.

If you are an MSM and have ongoing GI symptoms, you should discuss the possibility of a need for parasite testing with your provider.

If you aren't a hypochondriac and want more details read on, on the other hand, If reading about diseases makes you feel like you have them probably best to stop here as we've covered the basics and discuss your risks with your health care provider who specializes in caring for MSMs.

One of the biggest frustrations I've had in the 22 years I’ve been providing primary care to gay men is the lack of research done into basic illnesses that gay men are likely to have but that aren’t significant in the non-MSM population. That is, of course, unless there is the potential for a big blockbuster drug related to such research.

This is particularly evident in the case of intestinal parasitic infections and the lack of reliable testing, lack of recognition of the frequency with which gay men acquire these, and the failure to recognize that some of the parasites that are considered non-pathogenic (meaning they don't cause symptoms or harm) are actually very pathogenic for some people.

The four common intestinal parasites for gay men and MSM are Blastocystis Hominis, Endolimax Nana, Giardia Lamblia, and Entamoeba histolytica. With a few others like Cryptosporidium, Microsporidium, and Strongyloides also being possible but somewhat less common.

These can cause an array of symptoms varying from gas and diarrhea to a swollen prostate and colitis. More importantly, in some people, these can cause no problems at all. Allowing these people to go on for years spreading the parasites to others. For example, In 2009 in Barcelona 8 men were hospitalized within a 2 week period with E. histolytica that was causing proctocolitis. Of the 8 men only 2 tested positive for E histo when a traditional screening test was used. The other 6 were only identified as positive by specific antigen testing done on their stool. When their partners received testing, many were shown to have the infection but had no symptoms. How common is this? Well, studies done in the '80s showed that MSM had a rate of parasitic infection varying in developed countries from 1-22%, with New York City consistently showing prevalence near 20%. That means that nearly one in 5 MSM in NYC had intestinal parasites.

I have found that about half the time when an MSM thinks he has lactose intolerance, gas/bloating problems, irritable bowel or gluten sensitivity the diagnosis is either completely wrong and being caused by a parasite or the condition, if present, is actually milder and being exacerbated by a parasitic infection. Many patients tortured themselves thinking they had food sensitivities or irritable bowel disease. They developed elaborate diets and dealt with constant anxiety related to their bowel movements. Since avoiding lactose can often help alleviate symptoms of parasitic infections, lactose intolerance often gets blamed as the culprit. What's more, the traditional testing for some of these parasites is not very sensitive, and it's a shitty test for patients to have to do (see what I did there?). What is traditional testing you ask? Well, you have to bring one or two little bottles of liquid home, shit onto a piece of Saran Wrap or a special poop collector pan, scoop said shit into the little vials being careful not to spill the liquid and yet also to add just the right amount of shit (oh did I mention the liquid is poisonous). Then you bring the little vials with your poop in them back to the lab and usually have to hand them to someone who knows you are handing them a little jar with your poop in it and that you probably have bowel problems. After all that, this test, if done just one time is not very sensitive. For it to be sensitive in determining if a parasitic infection is present, it needs to be done 3 times in a row preferably on three different days. (yes you can collect all three specimens usually over a few days and then bring them all at once to the lab).

Needless to say, patients who are already anxiety ridden about their bowel habits aren't often excited to go through the diagnostic process and end up only tested once with a single specimen. When the test is negative it often confirms in everyone's mind that a parasitic infection isn't to blame. When in fact, that may not be the case. For Entamoeba, Giardia, and Cryptospiridium there are some excellent and highly specific tests however the provider needs to know to order them. Entamoeba, in particular, can be a severe infection for some people. Yet, for Blastocystis and Endolimax the testing is not as good, and patients often go undiagnosed and symptomatic suffering for years.

Why write all this? Well many MSM are embarrassed to talk about their bowel habits with their provider. Many providers know patients are unlikely to submit all three stool samples and order only one. Many patients google their issues and end up misdiagnosing themselves with things that are more common for non-MSM and don't even find out about or are aware of parasitic infections. So if you have a history of GI symptoms or have sex with a partner who does (any type of sex) think about discussing the possibility of parasitic infection with your provider. It may change your whole life.

Do condoms protect from parasites? No, not at all. Handling a condom after insertive sex without adequate hand washing, in fact, can be a perfect way for the disease to spread.

What kind of sex transmits parasites? Well, rimming (analingus) is the most common way you can transmit parasites but you can transmit them without having sex at all, in fact just failing to wash your hands thoroughly means you can transmit parasites to someone by handling their food, drinks, etc.

If it were up to me, it would be a recommendation that all gay men are screened annually for intestinal parasites. Unfortunately, it's not. As a patient however you can ask to be screened if you think you may be infected, but bear with the not so fun and annoying process of the testing!

If you have experienced a misdiagnosis with intestinal parasites, please share your story on my page.

References

Centers for Disease Control and Prevention (CDC). (2023). Parasites - Parasitic Diseases. Retrieved from https://www.cdc.gov/parasites

Chapman, A., & Fellows, J. (2020). The clinical significance of parasitic infections in MSM: An overview of diagnostic challenges and prevention strategies. Journal of Sexual Health and Medicine, 12(2), 89–102.

Fotedar, R., Stark, D., Beebe, N., Marriott, D., Ellis, J., & Harkness, J. (2007). Laboratory diagnostic techniques for Blastocystis hominis and its association with gastrointestinal symptoms. Clinical Microbiology Reviews, 20(1), 634–658.

Kirkcaldy, R. D., Bolan, G. A., & Wasserheit, J. N. (2019). Sexually transmitted diseases and public health implications of enteric infections in MSM. Clinical Infectious Diseases, 68(1), 123–130.

Molina, J. M., & Goguel, A. (2017). Cryptosporidium and Giardia among high-risk groups: Managing chronic cases among urban MSM populations. The Lancet Gastroenterology & Hepatology, 2(8), 580–590.