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Diagnosis, treatment, and prevention of chlamydia

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- [Voiceover] Let's say we have this gentleman right here, and I've drawn out his genitalia. This is the penis, the testicle, the prostate, the bladder, and the rectum above the anus, and we suspect that they might have chlamydia. They may have contracted chlamydia. How would we go through and diagnose that? Well, there are a couple of tests that we could use right off the bat to aid in our diagnosis, and in order to do any of these, we need to get a sample. And so, if this gentleman here is infected, and we're suspecting chlamydia, there may be some chlamydia reproducing and growing up his urinary tract. And so, what we need is a swab sample. So we would swab right here from the tip. So imagine there's a little bit of a sample here we've collected, and we can use a couple of tests to figure out if chlamydia is there. The first test we can use would help us look for chlamydia DNA. So I'm going to draw a strand of DNA right here, and as you might imagine, there's going to be a little bit of that present on this cotton swab that we've collected here. And we can't really see if there's any chlamydia, if we've only got this small amount of DNA or this nucleic acid. And so, what we want to do is multiply the number of nucleic acid samples that we have from this cotton swab, and once we do that, we have enough genetic material or nucleic acid that we can actually detect with probes. And this process of multiplying or amplifying the amount of nucleic acids we have from the chlamydia is done using a polymerase chain reaction. Maybe you've heard of PCR before. And to use this test to diagnose chlamydia is called a nucleic acid, nucleic acid amplification test, a nucleic acid amplification test, or it's also referred to as an NAAT. Now this test is great because not only is it fast, but it's also more sensitive. So more sensitive, I'll just write SN here, more sensitive and more specific, so I'll write SP, more specific than other tests, which means we're less likely to have false-negatives if it's very sensitive, and we're less likely to have false-positive if it's very specific. So it makes sense that this test is the most common one that we use to diagnose chlamydia. Another test that can be used is a traditional Gram stain, and we've talked about this before, but the steps of a traditional Gram stain just involve taking the swab that we got a sample from over here, and then we smear it on this microscopic slide, and then we add a series of several drops. So that would be one of the drops, and then over time we would watch it and add this drop as well, and this would help us visualize if the chlamydia bacteria are actually present here. But the problem is that chlamydia, because it's an intracellular organism, it likes to stay within cells, it's hard to see with a traditional Gram stain. So this test isn't often used anymore. Another test that can be done is to take the sample from our swab and put it on this petri dish. So I'll draw this sample being swabbed on this petri dish, and we let it sit and grow for about five days. So five days. And after five days, we would see that our petri dish here would start to grow some colonies of the chlamydia. So I'll draw a couple of these colonies all over here. And that's how we could figure out that this bug is growing in our patient. But as you notice, this test takes too long. It takes too long for us to get a conclusive diagnosis, which is why we've elected to use faster techniques nowadays. So after we've made our diagnosis, how do we treat chlamydia? Well, the mainstay of treatment will be antibiotics. Antibiotics. And to skip back a little, we can use this, and I forgot to label it here, we can use this culture test or this culture to help us figure out what antibiotics would work best against chlamydia. And we do that by smearing one antibiotic, say down here, and then a separate or a second antibiotic, number two, up there. So when we look at our culture five days later, we'll see that where antibiotic two was, there are some chlamydia colonies that are growing out. So it doesn't look like that antibiotic works very well to kill off the chlamydia. Instead, antibiotic number one, which we put over here, has a gap of colonies. There are no colonies growing around where we smeared it. So that's how we can figure out antibiotic sensitivity for the bacteria and do targeted therapy. So I'll just write up here, we can target sensitivity. And then, finally, maybe we can catch a person before they get chlamydia. And what could we do to help people prevent having the disease in the first place? So, steps for prevention. And with any infectious disease, the way to do that is to stop transmission. So we need to stop the spreading of chlamydia from one infected person to another. And remember, there are several ways that we can transmit chlamydia. Mainly through sex, and that can involve vaginal, anal, and oral sex. For all three of these, we can prevent transmission by using condoms. So that way we can decrease the amount of direct contact between an infected and an uninfected person. Another thing we can use specifically for oral sex are dental dams, with the same concept that we're decreasing direct contact. And finally, the last way we can transmit chlamydia is from an infected mother to her newborn child during childbirth, and the way we prevent this is just by treating mom, which is why all pregnant women in the United States are screened for chlamydia and gonorrhea on one of their first doctor's visits, and the main reason behind this is because 70% of infected women have no symptoms, which is kind of scary. It means that if a woman is pregnant and then delivers that child, it's very likely they can pass the infectious disease on to the baby without even knowing they had it, which is why it's really important to be checked and treated early on.