Bacterialvaginosis is a disease that's caused by the overgrowth of a type of bacteria that's called Gardnerella vaginalis, Gardnerella vaginalis. And as the name might suggest, this is the most common vaginal infection. Now I wanna put these really big quotes
around the term infection because the thing that's interesting about Gardnerella vaginalis is that it's a bacteriathat's naturally found in the vagina. Now some may consider this to be a sexually transmitted infection, which is interestingbecause it doesn't cause
any problems until there'stoo much of it there. So when we look to the causes of bacterial vaginosis, they are all things that change the vaginal environment. That can include acts like douching, so douching, or rinsing of the vagina. The other is having newor multiple sex partners.
And finally, another known cause is the use of antibiotics. This could be in the case of somebody that has a throat infection or a pneumonia that's on antibiotics which will then attackthe bacteria that exists within the vagina andallow Gardnerella vaginalis to overgrow and cause bacterial vaginosis.
So we've touched a little bit on it here, but I wanna draw it out. So when we talk about the pathophysiology of a disease, we'retalking about the mechanism by which that disease occurs. So in order to understandthe pathophysiology of bacterial vaginosis, we need to take a look at a sample of bacteria
that exists in the vagina. So I'll draw out someGardnerella vaginalis bacteria, and so I'll put this up in our key. This is the symbol forGardnerella vaginalis. And I'll draw a few of them around here, but I also wanna show that there are a lot of other bacteriathat exist in this sample. So if you really look at it here,
What is herpes
A cold sore onyour lips or on your genitals is referred to herpes, Ithink you might've heard that term before, andit's caused by a virus referred to as the herpes simplex virus. The herpes simplex virus orHSV comes in two flavors. There's HSV1, and there's HSV2. It used to be believed thatHSV1 mainly caused oral lesions, so I'll write up here oral,and HSV2 mainly caused
genital sores or genital lesions. But more recently, it's beennoted that HSV2 can cause oral sores, and HSV1 cancause genital sores as well. And in fact, this typeof infection is so common that 90% of Americans areexposed to this by 50 years old. So they're exposed in a variety of ways, which makes herpes simplex virus a sexually transmitteddisease, so if we talk
about the modes oftransmission or how it spreads from one infected personto an uninfected person, that can include sex,which can be oral sex, vaginal sex, or even anal sex. Childbirth is an importantmode of transmission as well. If an infected mother has any active sores while she's giving birth,her baby can get exposed to the herpes virus.
Or even outside of childbirth,any contact with open sores can cause transmission of the virus. Or if you were to come intocontact with the bodily fluid that's infected with HSV in another way, so if you were to share bodily fluids, like a healthcare workerthat gets stabbed by a needle that was used to draw bloodfrom a patient that has HSV, that counts as a modeof transmission as well.
And we'll talk moreabout that in a second. Generally, from the firstpoint of infection right here, so I'll write infection, and we'll make this type of timeline right here. It takes about four to seven days before the first sores appear. And once they're there,it takes about 10 days for them to heal up and go away.
There are six main symptomsthat I'll mention here, and we'll start off here, where you might recognizethis is somebody's lips right here, and they've developeda cold sore right there. The technical term for this,because it's caused by herpes, we call it herpes labialis. So for shorthand, I'lldenote this triangle to represent the HSV virus.
Diagnosis treatment and prevention of herpes
So we've talked quite abit about herpes already. The next step would be to understand how do we diagnose herpesé Well commonly what physicians will do is ask the patient abouttheir medical history, recent sexual practices, and other things that maysuggest a mode of transmission or some way the patient couldhave already been infected
with herpes. So combined with this history, and the symptoms thatthey may be exhibiting such as the cold soreeither on their lips, that's called herpes labialis or if it's on their genitals that's herpes genitalis. That's usually enoughto make the diagnosis.
And that's actually whatphysicians most commonly will do. Beyond that there are a coupleof tests that can be used to make the diagnosis. One test that used to bemore commonly employed is called the Tzank smear. The Tzank smear, which is named after afamous French dermatologist. So let me draw the French flag here.
Let's put in a littlered, white, and blue. So this test was first describedby a French dermatologist and what they would dois take a swab sample of a cold sore or an ulcer. So here's our sample right there and that sample would be appliedonto this slide right here. So let's smear the sampleonto the slide right over here and then what you'll seeafter adding a stain.
This could be either a Giemsa stain or a Wright stain, so don't worry about those names, but there's a specificdye that's added to this, so I'll just write up herea dye of some sort is added and what you should seeif this patient has herpes are these giant cells. These are supposed to be epithelial cells
from the swab of the lipor from the genitals, so that's one giant cell. So I'll write down here wesee a couple of giant cells. And there are a few other here. But what's interesting about these cells is that they don't have just one nucleus. There are several of them. So I can count oneish right there.