I have fielded so many emails that ask me to make a video about this and now that I'm finally doing it I just want you guys to work through this with me we're gonna make everything make sense and seem logical so that you once and for all understand the differences between these four very similar diseases so what we're talking about today is cholelithiasis cholecystitis co-leader Kola theosis and cholangitis also sometimes called ascending cholangitis now the first thing we need to go over before we even start is which of these is the most severe and which of these is the least severe and that's why I have this slide at the top starting with cholelithiasis that is the least severe of these four disease processes but cholangitis at the bottom is the most severe just keep that in the back of your head as we move through this so you can kind of triage what's important when you get a question about one of these on your USMLE now we're gonna go over the biliary tree and this is the picture that we're gonna use throughout the duration of this lecture what this shows here is that you have a liver which is drained by a right and left hepatic duct you have a gallbladder that's drinking by the cystic duct those three ducks come together and form the common bile duct the common bile duct is also joined by the pancreatic duct which is not shown here but the pancreatic duct connects to the big fat common bile duct and then together all of that flows down and empties into the first part of the duodenum in the small intestine so let's talk about the four different disease processes that all start with C hol and we're gonna differentiate them and make sense of them all so the first one is cholelithiasis so what a collie the flyest is what what does that mean what that means is that there are stone formation inside of the gall bladder so what you see here are these red little stones inside of the gall bladder now the key to picking this out when they describe a patient to you in the question is that the patient typically will have colicky pain right waxing and waning in the right upper quadrant sometimes they'll have cramps and then they'll disappear and then they'll come back and then they'll disappear that's the key pain and it's very classic of cholelithiasis and it's oftentimes worse with fatty foods because as you should be well aware when the gallbladder contracts it secretes a substance that is used to break down fats and that is really the job of the gallbladder so that's why this colicky pain is worse sometimes in the question stem they'll tell you that a patient ate a cheeseburger two hours ago and has had this often on pain in the right upper quadrant the thing that you need to remember is that first of all the stones in the gallbladder is fine if it's not obstructing the gallbladder are not causing symptoms but just happens to be an incidental finding on imaging you can leave it alone you don't have to do anything about it it's only when the pain becomes really really bad that you need to treat it so let's talk about diagnosis and treatment to diagnose cholelithiasis you would do a right upper quadrant ultrasound very simple that's always the right answer if you suspect cholelithiasis you do a right upper quadrant ultrasound and what you'll see is something called acoustic shadowing now I recommend that you google what acoustic shadowing looks like but basically because you have these stones inside of the gallbladder they're obstructing the light in such a way that it looks like there are these projected shadows coming across the gallbladder and that shows up on ultrasound and that's very pathognomonic for gallbladder Kali Lilith Isis because it tells you that there are stones sitting in there the treatment for cholelithiasis is elective cholecystectomy now the reason that elective is in there is because that word is important you don't have to do this right away you can take out that gallbladder but it's not an emergent procedure you owe the gallbladder coming out really depends on the symptoms of the patient and that's the bottom line now not included on this slide or the difference between cholesterol gallstones and pigmented gallstones and I suggest that you familiarize yourself with the two of them but just know that there are a couple of types of stones that can be found in the gallbladder and you should also know what contributes to each of them so instances where you'll get cholesterol stones is when you have super saturation of cholesterol instances when you'll get pigmented stones usually have to do with hemolysis those are some things to file away in the back of your mind but the goal of today's lecture is to really help you differentiate cholelithiasis from the a pedo biliary disease processes so again if I were to rapidly summarize cholelithiasis I would say that it's stones that are formed in the gallbladder as a result of either cholesterol super saturation or hemolysis forming one of two different types of stones the patient classically has right upper quadrant colicky pain they usually don't have a fever or any other systemic signs you diagnose it with a right upper quadrant ultrasound because it's cheap and non-invasive and you do an elective cholecystectomy because you don't have to take it out right away since it's not seriously life-threatening that is Kali Lilith Isis now we're gonna move on and talk about something a little bit different the next thing is cholecystitis so let's start about the basic bare-bones difference between cholecystitis and cholelithiasis Kali lift Isis lift L ith means stones so there were a bunch of stones in the Koli Koli lift Isis Kali cystitis is inflammation itis of course means inflammation and cystitis means inflammation in the cystic duct so how this works is a stone gets lodged in the cystic duct and and everything behind that stone becomes inflamed so the cystic duct and the gallbladder now Kali cysts itis it makes perfect sense if you think about the name the cystic duct is inflamed and the gall bladder behind it is inflamed so how do you differentiate these on physical exam of course both patients are cholecystitis patient and a cholelithiasis patient have stones the difference is that insist itis there's inflammation because the stone is lodged in the cystic duct okay so this is cystic duct obstruction Koli with Isis is just stones hanging out nothing's become inflamed or obstructed this patient will have a Murphy sign that's really high yield and you need to be familiar with it they'll describe it to you they'll say that the patient takes a deep breath in and the physician kind of pushes their fingers and adds pressure around the edge of the liver when they do this the liver and the gallbladder drop down onto the physicians hands and when that happens because the the cystic duct and the gallbladder is so inflamed it hurts so if there's pain when the patient inhales and the physicians adding pressure in that right up that's a positive Murphy sign and that is pathognomonic almost for cholecystitis so what's the difference in cholecystitis the patient will have constant pain it's not colicky it doesn't come and go like in Kali Lilith Isis it's constant this gallbladder is inflamed there's no period where it's inflamed and then it's not it's inflamed and then it's not in kalila diocese those stones are churning around and that's why you have that colicky pain that comes and goes because the pain is dependent on the position of the stone but in cholecystitis the stone is blocking the cystic duct the gallbladder is contracting against an obstruction that's why it's inflamed and that's why there's constant pain now on labs they'll give you a fever and a leukocytosis so if you see an elevated white count and a fever you have cholecystitis because again fever and an elevated white count is classic for inflammation and cholecystitis is inflammation to diagnose kali cystitis you you still want to do a right upper quadrant ultrasound again that's usually should be your first line guess when it comes to biliary pathology because it's so cheap and not invasive but if you think if you can't do an ultrasound or if that's not an option you want to do something called a Haida skin no I think that you should Google a gallbladder high to scan and see what that looks like but basically you're seeing can the gallbladder take up this special kind of dye if it can it's all good but if it can't it's because the cystic duct is obstructed so it kind of makes sense what the image looks like and I suggest that you google that to see treatment here is gonna be cholecystectomy this is a little bit more serious than cholelithiasis I told you in cholelithiasis you can do an elective cholecystectomy but here you gotta take the sucker out it's inflamed and you don't want to infarct any area in the biliary tree so you got to take it out you just got to remove it so if I were to summarize Chloe cystitis in one really quick high-yield manner I would say the cholecystitis just as the name implies is an itis of the coaly cyst in other words it's inflammation of the cystic duct due to a stone getting in there there's a positive Murphy sign and constant pain the reason for this is that the pain is just there because it's all always inflamed there's no coming and going the gallbladder is contracting against a closed space and it's causing the patient lots of pain the Murphy sign is there because the gallbladder comes down on the physician hands during this maneuver and that hurts because it's inflamed the fever and leukocytosis should tip you off that there's inflammation which will further help you differentiate it versus cholelithiasis where there's no inflammation to diagnose it you want to do a right upper quadrant ultrasound because it's cheap and non-invasive but if that's not an option you want to do a high - scan because the height of scan shows you if the gallbladder can perf use this special dye the treatment is a cholecystectomy and this is not an elective procedure the gallbladder has to come out because it's inflamed and you could infarct it now let's go on to the next pathology here coley dhokala diocese so let's say that the stone that was in cholecystitis went a little bit further and this time got lodged in the common bile duct that's what we have here so coal edokko just means common bile duct so the first two letters of common are Co SoCo Lido Co with aya Sissoko for common bile duct and then La Fea sis again means stones just like cholelithiasis mint stones in the gallbladder dokgo Matthias this means Co with Isis common with diocese so that's where this comes from this is a common bile duct obstruction you get proximal inflammation things before the stone will become inflamed but usually in a colloid ocala diocese there is no inflammation it's just the stone hanging out in there so there's no fever and there's no leukocytosis but what there is is something called obstructive jaundice so because you can't drain bilirubin from the biliary tree you have a backup of bilirubin then the patient becomes jaundice right they'll become yellow they'll get squirrel icterus their tongue in their mouth will become yellow they'll have an increase in their bilirubin levels what you see here and what's pathognomonic for co-lead ocala thigh assists are dilated hepatic bile ducts so because the liver is trying to drain into this area that is obstructed it can't do it so the two hepatic bile ducts that usually drain from the liver will become dilated because all of that bile flow that's coming out of the liver is backing up now let's talk about the treatment the treatment is going to be ERCP and basically what an ERCP is is a gastroenterologist will put a scope down and get into the bot into the biliary tree and ERCP he'll be able to see what is in there and we'll also be able to remove a stone if the stone is in there so it's really high yield to know that ERCP is both diagnostic and therapeutic not only can you see with the scope what's going on but if you need to you can remove a stone while you happen to be in there and that's important because there's an alternative test called an M RCP and that's only diagnostic the MRCP cannot remove stones but the ERCP can so that's what the treatment is here so it's both the diagnosis and the treatment the reason that we use ERCP is just it has better sensitivity and specificity for diagnose and co-lead ocala theosis when compared to a right upper quadrant ultrasound a right upper quadrant ultrasound may still show you that there's a stone here but the ers EP will definitively tell you if there is a stone and also you can remove it so co-leader Coelophysis if I was gonna summarize it I would say that it's latias of the coal edokko again Kohli doko means common bile duct lathy assist means stones so it's a stone in the common bile duct now for the most part this causes a little bit of inflammation proximal to the stone but no fever no leukocytosis and no major pain it's typically a non inflammation process a non inflammatory process it does cause an obstructive jaundice remember bile draining from the liver can't drain it backs up and causes jaundice in the patient and dilates the hepatic bile ducts if you see the words dilated hepatic bile ducts the answer is Co Lido Coelophysis the treatment and the diagnosis is e r CP all right let's talk about the last biliary disease process it's called cholangitis now cholangitis or sometimes called ascending cholangitis is when you have a co-lead oh cool with Isis and then you get an infection that's why Co Lido Coelophysis needs to be treated promptly with ERCP because it can progress to a cholangitis now the reason that they call it an ascending cholangitis is because the stone gets lodged in the common bile duct just like we saw on the last slide in Coley Dhokla with Isis what happens next is that because you have this closed system where there's backed up fluid that is an itis for infection so you have this infect that ascends up the biliary tree and causes inflammation and everything proximal to the obstruction that's really high-yield so you will have shark o's triad and occasionally Reynolds pentad shark O's triad is fever jaundice and right upper quadrant pain you're always gonna have shark o's triad that are always gonna give that to you on a physical exam fever jaundice and right upper quadrant pain the fever in the right upper quadrant pain are from the inflammation and the jaundice is for the same reason Kali local elias's caused jaundice you have an obstructive jaundice again now this can progress to something called Raynald pentad and that is when you add hypotension and altered Mental Status at that point you're kind of progressing into the realm of this patient might be going into shock and that's what you get oftentimes this is a misdiagnosis because someone will come in with white or right upper quadrant pain and they won't really know what to do or what to look for maybe they'll think it's um you know like just a basic stomach issue but the patient is quickly progressing through these stages and moving into shock so it's got to be treated emergently to diagnose this you do a right upper quadrant ultrasound the patient's gonna be in a ton of pain you're really not gonna want to mess with them you're just gonna get a non-invasive ultrasound and then you treat this with an emergent ERCP you have to take out that stone it's gotta go the patient could go into shock and die literally if you don't get this out and that's why cholangitis is the most severe of these four now let's think about this itis it means inflammation cholangitis it is the one that kind of sounds the most different from the other three so because it's the most severe and because it's the most different you can kind of think of the picture mentally and see how different it is I mean this is inflammation of the entire biliary tree it's severe so let me summarize cholangitis for you in one quick high-yield way colon gitis also known as ascending cholangitis is when there is a stone that gets into the common bile duct and causes an infection it's basically a co-lead o caliph is s + and infection you have shark O's triad 100% of the time fever jaundice and right upper quadrant pain if the patient progresses and they get worse they can develop Reynolds pentad we Charcot triad plus the addition of hypotension and altered Mental Status it is a poor prognostic factor and may indicate that the patient is going into shock to diagnose this you want to quickly get a right upper quadrant ultrasound because it's non-invasive and will not cause the patient any discomfort and then do an emergent ERCP to pull up the stone that's obstructing the system that's it here's a summary slide with all four broken into four quadrants you really want to know the difference between them I suggest that you review this video and review how the name can tip you off as to what is going on in the disease process differentiating these four is extremely high yield and USMLE and comlex will commonly give you a patient with vague right upper quadrant symptoms and expect you to interpret labs and interpret specific excerpts from the question stem and determine which of these four it is these are usually all pulp possible answer choices so know them well good luck