hi welcome to sketchy micro this is Andrew we're going to knock out three members of the interactor aier family all in one video this is a little more ambitious than normal but I think we've grouped them nicely so it shouldn't be too bad the three we're going to cover are interactor Sera and cbella or as we at sketchy micro know them as interact triaa tops and finally this ankasa orus with a club tail or KB tail will be cbella we're going to set this scene in a hospital room of a patient so let's get that drawn all right now we'll give this guy an oxygen mask and this will represent that he has pneumonia and down here we're going to have this bag of urine hanging off the bottom of his bed and this is to show you that he has a urinary tract infection and as you probably guessed pneumonia and UTI are the two most common illnesses caused by these bacteria and the reason we chose the hospital is because all of these are really important nosocomial infections or Hospital acquired infections and a big reason why it's important to know that it's a hospital acquired infection is because that means that you want to think uhoh there may be some multi-drug resistance here and in this case all three of the bacteria we're mentioning have multi-drug resistance and you'll probably want to remember that and we'll make sure to do that by drawing a bunch of pills on the ground next to the patient to remind you that patients in hospitals are taking a lot of antibiotics so a lot of the bacteria that you find in hospitals are multi-drug resistant and that goes for these three especially and when you get a question on how to treat an infection by one of these guys you'll want to think along the lines of a carop penum where resistance typically isn't seen so so far we have that they're all multi-dg resistant and that they're all nosocomial infections and they most often cause pneumonia and UTI and there's really only one more important shared feature that we have to cover and that's that they all ferment lactose this characteristic is often one of the first mentioned in questions to help differentiate between the various interacter aier the only other important lactose fermentor you'll have to remember is eoli which we're going to cover in another video so right away if you see that a culture can ferment lactose these could be part of your differential so to remember this we're going to draw a milk carton because of course milk has lactose so when you see it you should think lactose fermenters and also take note that we're drawing the milk carton pink why is this important well lactose fermenters form pink colonies on Cony Aur so it's kind of a two for one the milk represents lactose and the pink color for the pink colonies on makon augur and I really can't hype this aspect enough you have to remember that these are lactose fermenters if a question stem gives you that an isolate was taken and grown on makon AER and formed pink colonies I mean that's a huge help that really narrows it down to these and eoli so you have to be able to recognize that and of course after I've really stressed that there is a caveat but it is really pretty low yield so feel free create to plug your ears and hump for the next 5 seconds I won't be offended but I do need to mention it for completeness sake so Seria does ferment lactose but it does so really slowly so sometimes it can actually show up negative on a lactose fermentation test so don't necessarily rule it out if the organism isn't a lactose fermentor but luckily there are easier ways to tell its San culture and we'll discuss that in a bit again everything we've added so far applies to all three species of bacteria so maybe pause the video here rewind and make sure you're comfortable with all of these features before we start drawing them out individually okay well let's add our prehistoric friends one at a time starting with the lower yield ones and eventually we'll work our way over to the high yield clella let's start with interactor interactor was actually the major inspiration for the whole dinosaur theme because it just sounded so much like pterodactyl so let's draw Inaba or in pterodactyl flying over the patient a quick disclaimer here if in real life your patient starts to complain about seeing little dinosaurs flying above them you might want to consider turning down the ketamine drip anyway interact is flying so it's very clearly modal only San and teract display motility within this sketch and you'll see that later after we finished all three of them and really there aren't many more defining features for interactor so that's great for us now let's get to Sera which is actually my favorite of the three Sera will be represented by a triceratops or as we called it earlier Tria tops and we're drawing him as if he were kind of In Motion charging with his right arm up this is to remind you that he to is modal remember of the three only kbell will be immot so let me tell you why s is my favorite it produces a red pigment when cultured and you've probably actually seen this pigment and just didn't realize it if you're like me and when studying for the boards you may neglect some of your daily chores especially in the bathroom and you get that pink ring around your shower well that pink pigment is actually from Sera and that's the same pigment you see when it's cultured so you can think about that the next time you shower or you can remember that tricera tops is bright red so that should remind you of the red pigment that Sera produces all right so if you had a really awesome childhood then you probably went through a dinosaur phase like I did in fact if you were a boy and you didn't want to be a paleontologist I'm willing to bet you probably didn't have many friends but on the other hand if you really really really like dinosaurs and actually became a paleontologist you probably still didn't really have many friends I'm just kidding I'm just kidding I know we have a massive paleontology following so I don't want to offend any of you anyway if you know dinosaurs then you've probably heard of the inosa surus you might also remember they have that club-shaped tail and that club will remind us of kleb siella and actually our club tail will have these three spikes that have A's in them and these are three A's to remind you of the Three A's of C which is alcoholics abscesses and aspiration that means that they commonly infect alcoholics they commonly create abscesses and they commonly get started from aspiration and the ankos aurus also has these really thick shell-like scales on its back and this is perfect for us because klebsiella actually has a capsule so we'll cover the spiky scales on his back with this mucus substance to remind you of polysaccharide capsules so how can you tell that klebsiella is the cause of a patient's pneumonia well a common clinical feature that becomes kind of a buzzword for many students is that these patients cough up a current jelly sputum the boards don't generally go for such obvious buzzwords but you may see it in your class exam so we'll include it so we'll draw clipa knocking over a Jar full of currant jelly that should be a pretty obvious reminder Additionally the jar has spilled its contents all over klebsiella and it's sticking him to the table almost like a tarpit and this demonstrates that kbella is the only one of the three that's immot especially in contrast to the other two which are clearly active and definitely demonstrating motility and a little Subs sketch we'll include just for fun is this chest x-ray and you'll notice if you look closely you see this cavitary lesion on the patient's right lob well that's to remind you that kle yellow ya forms abscesses but also that if you looked at this chest x-ray you might originally think it was TB so in a question stem you might get something where you know they originally thought it was TB or something that really makes you think it it is TB but you have to keep cbella in mind all right we're almost done with the drawing but there is one more fact about cbella you have to know and for this last point I'm going to bring up the drawing from Proteus so here it is and you see that Proteus is spraying the bathroom stall with the bottle of ammonia well this bottle of ammonia represented Urias and Proteus is really the main Urias producer you have to remember but cleola actually is too it's not really as important as it is for Proteus but you just have to remember that so we're going to the same symbol in this sketch to make it easy and have the patient squirting a bottle of ammonia at Cella and with that we're done thanks for listening I really hope you got something out of it if you liked it leave a comment we really like hearing from you guys and we'll do our best to get you some new videos in the near future thanks a lot [Music]