How Do You Get a UTI? Urologists Explain Why These Infections Develop
Urinary tract infections (UTIs) can seem to arrive out of nowhere. One minute, it's business as usual when you're doing your business. The next, you're experiencing all the telltale UTI symptoms (think pain and burning when you pee, a never-ending need to go to the bathroom, maybe a little blood on the toilet paper).
The situation's definitely no fun, but understanding how you get a UTI can help you know what's going on in your body and how to deal. Let's take a closer look at what causes a UTI and where those germs come from to begin with.
How do you get a UTI?
You don't need an advanced degree in biology to learn the basics of how you get a UTI. There's actually a pretty simple explanation.
"You get a UTI when bacteria from the vaginal and anal area enter into the urethra and bladder, and set up a bacterial colony, typically on the surface of the bladder," explains Patricia A. Wallace, MD, a gynecologist and urologist at Providence Mission Hospital in Southern California.
In other words, some less-than-welcome guests crash the normally chill party of good-for-you bacteria in your urinary tract and cause problems.
If you want to point fingers at what's to blame for your UTI, Escherichia coli is probably the culprit. (Yes, that same E. coli that has contaminated lots of salad greens in recent years.) It normally lives peacefully in your bowel, but if it enters the urinary tract, you're on the fast-track to a UTI.
E. coli is responsible for up to 90% of all UTIs, according to the University of California San Francisco. However, it's not the only foreign invader that can wreak havoc on your bladder and urinary tract. UTIs can also come from bacteria like streptococci, klebsiella, and proteus mirabilis, according to the Merck Manual, and sometimes even fungi.
What's causing your UTI might sound like a minor detail (after all, it's hard to think about much else when it feels like you're peeing fire), but it can make a difference when it comes to your treatment. Your doctor can send a sample of your urine to a lab to figure out which pathogen is causing the infection and get you the right medications to clear it up, usually offering sweet, sweet relief from burning, painful pee in a few days.
How do you get a UTI in the upper tract?
An untreated UTI could eventually lead to an upper urinary tract infection. You get an upper UTI when those nasty bacteria that have made your bladder their home decide to travel up your ureters and set up shop in your kidneys, as well.
If that happens, you'll want to take care of it right away. This type of UTI can lead to permanent kidney damage or even a life-threatening condition called sepsis.
In addition to the painful urination and cloudy or bloody pee many people have with a lower UTI, look out for upper UTI symptoms, such as:
- pain on your side, back, or groin
How do women vs. men get UTIs?
Just like women, men also have urethras and bladders that are vulnerable to bacterial infections. Yet, UTIs happen 30 times more often in women than men. What gives?
You can blame anatomy for that one, says Jennifer A. Linehan, MD, a urologist and associate professor of urologic oncology at the Saint John's Cancer Institute at Providence Saint John's Health Center in Santa Monica, California.
"The urethra is very short in women, whereas in men, it's very long," she says.
In fact, a woman's urethra is usually no more than 1.5 inches long (roughly the length of the first two joints of your index finger). A man's urethra, on the other hand, stretches between 7 and 8 inches long—almost as long as a plastic straw. That means bacteria have to travel a lot farther to infect a man's bladder or other parts of his urinary tract and could get flushed out by pee before they ever have the chance to make a colony.
The location of the urethral opening is also another point to consider when it comes to how you get UTIs as a woman compared to a man. For women, it's located in between the labia in front of the vaginal opening, which just so happens to be pretty close to the anus (where you might find E. coli). Since a man's urethral opening is on the tip of his penis (far away from the anus), it's less likely to come in contact with the bacteria.
With all that being said, it's still possible for guys to get UTIs, just much less likely.
Common causes of UTIs
You've already got lots and lots of bacteria in your urinary tract—and that's a good thing! They help keep you healthy and everything normal. So how do things take a turn for the worse?
Here are some ways you can get a UTI:
- Sex: Doing the deed can result in a UTI for a few reasons. "Sexual intercourse is the biggest trigger for UTIs in young women," says Dr. Wallace. "Sometimes there can be stool contamination in the area." Put another way, you could accidentally spread poop particles into your urethra when you're getting frisky. That's why people prone to UTIs often swear by peeing after sex as a prevention tactic.
- Your birth control can also hike up your risk of a UTI, according to the National Institutes of Health. Diaphragms can slow the flow of your pee and spermicides can irritate your skin—two situations that bacteria love.
- Wiping back to front: Wiping the wrong way is another reason you can get a UTI. "Wiping can put the bacteria in the wrong place. That's why you want to wipe front to back," says Dr. Wallace.
- Kidney stones: As if kidney stones weren't bad enough on their own, these hard deposits can also cause a UTI. "Some patients can have kidney stones that are colonized by bacteria," says Dr. Linehan. "If you give them antibiotics, it will treat the infection, but the stone can still be a safe harbor for them. Once the infection is gone, the bacteria living on the stone slowly come out, grow, and boom—we have an infection." Kidney stones can also cause UTIs if they block your urinary tract. That makes it difficult to fully release all your pee, creating a breeding ground for bacteria.
- Holding your pee: While you don't have to rush to the bathroom the moment you feel an urge to go, holding your pee often can create an environment for bacteria to thrive and infect your bladder. "If you've been exposed to bacteria, and you're not emptying out, those bacteria have time to fester, multiply, and grow into tissue," says Dr. Linehan. To be clear: It's not waiting too long to go to the bathroom that causes the UTI. Rather, it gives any existing bacteria in your body a bigger opportunity to turn into a full-blown infection.
- Wet bathing suits: Sitting around in a wet bathing suit won't directly be the reason for an infection, but it can cause a UTI by creating a bacteria-friendly environment, says Dr. Linehan. "Any place that's a moist environment can always harbor bacteria," she notes. The same goes for damp underwear or sweaty gym clothes. Try to keep the clothing around that area dry to avoid bacteria.
Regardless of how you got a UTI, it's important not to ignore it. Sometimes they can go away on their own, but many people need a short course of antibiotics to evict that bacteria from their bladder. If you have symptoms of a UTI, get it checked out by a doctor ASAP.
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