 Hi everybody, Dr. O. In this video we're going to talk about vancomycin. So first of all, the name comes from the word vanquish. So this antibiotic was developed to deal with methicillin-resistant organisms. So we coded the world in penicillin and bacteria responded by developing penicillinases or beta-lactamases, the molecular scissors, the enzymes that chop up penicillin and that nucleus. So then we threw methicillin at them and they developed MRSA, methicillin-resistant staphylococcus aureus. So methicillin-resistance became a problem. So then we came back with vancomycin and truly when I was in school and even just a few years ago they were talking about this as our last line of defense against MRSA. Thankfully, it's not true anymore, but that was kind of our hubris, right? We thought that this was going to be the antibiotic that won. But if you understand evolution, they're always going to keep trying to find ways around the antibiotics. So now thankfully we have last lines of defense for the organisms that resist vancomycin and so on and so forth. But let's talk about vancomycin, the antibiotic first. So it is a glycopeptide antibiotic. It's a large structure. What this one does is different. The cell wall inhibitors we talked about before, the beta-lactam, they actually interfere with the fusion of the carbohydrate backbones and then the peptide chains holding them together. Vancomycin does the same thing, but in a different place. It actually blocks the proteins so that they can't actually be incorporated into the cell wall. The vancomycin is only effective against gram positives. It actually can't penetrate that outer membrane of the gram negative bacteria. So this is a narrow spectrum antibiotic only going to be used against gram positives. It is effective against some of the strains of MRSA, right? So that's what it was primarily used for is as a last line of defense against MRSA, methicillin resistant staphylococcus aureus. But of course, then evolution does what it does. And now we have MRSA, which is vancomycin resistant staphylococcus aureus. We have VISA, vancomycin intermediate staphylococcus aureus, which means not fully resistant, but you're going to have to use more vancomycin to treat it. Some would say four to eight times more. That's what intermediate means. It's not fully resistant, but it's going to take more drugs or a combination of drugs to be effective. VERSA, so and we'll come back to the area in a second, but VERSA is vancomycin resistant. What you would use primarily for a VERSA organism at this point would be a daptomycin, which we'll cover that antibiotic in a different video, or at least use a combination of antibiotics, so maybe daptomycin plus something else. Combinations of antibiotics are definitely becoming more common because they certainly may be more effective, but they also may slow evolution. I can't say yes, but at least you're making it evolve around multiple different mechanisms. The last and to me the scariest vancomycin resistance at this point is called VRE, so vancomycin resistant enterococci or enterococcus. The two big ones that are talked about the most or they sound similar, but enterococcus, feciam and fecalis, I'll put them up on the screen. So these are common nosocomial problems in the United States. Nosocomial, the word is Latin for hospital, but it's a healthcare associated infections. So VRE is another one of the resistances that we've seen from this. So that's vancomycin. That is how it works. That's when it works and then here the result of using it or we could say potentially overusing it has been these different resistance diseases. All right, have a wonderful day. Hope this helps, be blessed.