Diagnosis of Key Liver Diseases – Hepatitis A, B, C vs. Alcoholic vs. Ischemic (AST vs ALT Labs)



okay so welcome to another med cram lecture we're talking about liver function tests it's the third lecture where we could talk about actual diseases and I wanted to break them up into acute liver diseases chronic and finally cholestatic so let's get started okay so here I've made a table of some of the characteristics of hepatitis in the acute form let's talk about hepatitis A remember that hepatitis A is an oral transmission so you don't get it by blood you get it by so I'm not washing their hands and then getting into the food and then there's some sort of a fecal oral transmission you get it but because this is the liver you're gonna see an increased amount of alt over ast both go up but you're gonna see more of an alt type of bound up over the ast and so how are you going to diagnose this remember it's the eye G M anti hepatitis A virus okay so that's how you make the diagnosis now with hepatitis B on the other hand it's not oral but it's intravenous intravenous or body fluid okay and in this situation it's very similar to hepatitis A and that the alt is going to be higher than the ast because this is the liver that's being attacked and not muscle or something else with hepatitis B remember there's different antigens there's surface antigens and there's cor antigens and that's important because if you get an immunization you're gonna have antibodies against the surface antigen so if I could draw a little example here if this is the virus particle the blue is the surface and the core is the green the core is the actual viral particle so when they give a vaccine they're just using the blue portion of the virus the non-infectious so you're gonna have antibodies that are gonna be made against the surf antigen so you so if you have an immunization you should be surface antibody positive but you should be core antibody negative because they never gave you the core and so what this means is that you should the IgM antibody to the hepatitis B core antigen should be positive if you actually have the infection let me restate that here so the i GM core antibody is positive again the IgM antibody to the hepatitis B core antigen is positive that's called the IGM anti-hbc c stands for the core and you should also have it positive to the surface antigen so both of those should be positive okay because in an actual infection you're getting the surface and you're also getting the core so you should have i GM you should have both of those so again the IgM antibodies at the hepatitis B core antigen and to the hepatitis B surface antigen both should be positive okay what about hepatitis C again hepatitis C is actually a little bit more chronic and so you're not gonna see as much of an increase here but again the key point here is the ast is gonna be less an increase than the alt again this is intravenous drug use or IV DEA abuse okay there's other things that are associated with this like tattoos also sharing razors multiple sex partners these sorts of things can increase the risk of spreading hepatitis C now how do you check for that it's very simple it's simply the aunty HCV antibody into IgM you could also check for the hepatitis C virus RNA within the first three months of the exposure you should have an antibody reaction though alright let's talk about alcohol now whereas before the alt was higher than the ASD because this is the liver be aware that in alcohol they're about the same or you might even see that the ast is going to be higher than the alt isn't that interesting and obviously here instead of intravenous drug use we're gonna get alcohol use so that's that's obviously very important difference there obviously you want to make sure that there's not other things going on here so the diagnosis is basically based based on history what about ischemic now remember an ischemic you're getting no blood flow to the liver so the liver is gonna be really upset with that and it's gonna tell you that and so what you're gonna see is humongous raises in the ast and the alt and we're talking several thousand here okay so they really go up in ischemic disease and obviously you're gonna have blood pressures here in the 50s / 30s or something really bad like that or a code situation and again you're gonna be ruling out other things here but if you see this go up and shoot up pretty quickly I want you to think of ischemia and you just again it's gonna be based on the the history okay let's talk about the chronic diseases now obviously you can get chronic hepatitis B and C and you don't get chronic hepatitis A or it's very rare so I left those off of here basically they look identical as to the acute situation except the liver enzymes are not as elevated let's talk about Nash probably one of the most common it stands for non-alcoholic steatohepatitis basically these patients are fat obese so you're talking about patients with for instance the metabolic syndrome insulin resistance hypertriglyceridemia and that in the history you're going to basically get for the diagnosis is that of exclusion you certainly don't want to just look at someone say they're fat and that's why you've got Nash but these type of patients what do they look like these patients are liver patients so they're going to have a slightly increased alt over that of the AST but the alt will be higher than the but it'll be it'll be elevated now as we said with alcohol it's very it's just backwards the alt is high but the ast is what's elevated and again the history is going to be that of EtOH and a guess it's also gonna be of exclusion you want to just make sure that you're not just as subscribing somebody to the old alcohol reason for their liver disease make sure that even though they're drinking make sure you rule out the other things autoimmune hepatitis that's that's the reason why we need to rule this out if you have a middle-aged woman who drinks a lot you certainly don't want to say that it's due to just for drinking because it could be due to autoimmune disease these are the type of patients that get autoimmune disease these young women so because it's an autoimmune hepatitis again it's in the liver they're gonna have a higher alt than ast so the history in this is that they're young women that's the type of people who get these autoimmune diseases and the thing here that you got to know is this this is for boards and it's the anti smooth muscle antibody if that's positive it's gonna be very difficult to say that this is all related to alcohol disease so look for positive Auto antibodies anti-nuclear antibodies but specifically the answer they're looking for is anti smooth muscle antibodies ok hemochromatosis this is uncommon in women it's usually because why they have periods and they lose iron so they it's very hard to store up with iron but the history here is that it's typically in men and what are we gonna see here well if you take the ferritin level and the iron saturation that's the where you take the iron the serum iron and divided by the TI BC you're gonna get something greater than 55% and usually you're ferritin level is greater than a thousand so you're off the charts with this and of course the history is that of something called bronze diabetes and this shows up on test a lot and the reason does is because it's going to very specific presentation basically iron infiltrates a lot of the endocrine organs of the body the iron infiltrates the pituitary okay so they can get pituitary problems it infiltrates the pancreas so what do they get they get diabetes it infiltrates the heart so they get what and CHF or some sort of constrictive cardiomyopathy okay so look for this patient with diabetes who has a bronze look to themselves now there's an iron metabolism deficiency that you should know it is on chromosome six and how do you remember that I remember that iron comes in a 2 plus form and also in a 3 plus form the Pharos and the ferric form and I know that 2 times 3 is equal to 6 so that's how I remember it's on chromosome 6 I don't think they will ever ask you that but you can certainly impress your friends with that bit of knowledge ok what about Wilson's disease I think Wilson's disease showed up on a famous television show once and those of us who studied knew what the diagnosis was before the end of the show you're gonna have increased alt and ast the history here with Wilson's disease is that they're young they get this kind of korea form movement disorder and psychiatric disease but the key here is this thing's called the kaiser ka y ser Fleischer f.l.e.i.j.a sche are rings so google that or look that up on the internet and see what kaiser Fleischer rings are in the eyes and you will see that and the key here is not a high but a low zero plasmon and why is that because it's trying to suck up all the copper this is a abnormal copper deposition so you get hemolysis and actually you get a low alch foss and a low cerumen plasmon ratio okay and now the one that's most near and dear to my heart is alpha 1-antitrypsin these but typically we see this with patients with lung disease remember antitrypsin alpha-1 antitrypsin is an enzyme that is in your lungs it's made in your liver as well and what it does is it protects these elastase –is from breaking your elastin fibers and so if you don't make alpha 1-antitrypsin you have something called alpha 1-antitrypsin deficiency and you tend to get emphysema more quickly well that's not the only thing that can happen you can get a buildup of this abnormal protein in the liver and you'll see these past positive paths positive granules in the liver and you will get liver disease it's a very kind of a low-level liver disease so you're not going to see it going very high but on the history you're gonna have COPD asthma certainly if they smoke very early in life if they don't smoke they'll have COPD later in life in the scratch your head say well how did I get the COPD I've never smoked well get an alpha 1-antitrypsin level the thing that you should know there is the worst form of it is the p i– z z allele okay and the normal is the mm but the z z is the worst and that's homozygote recessive okay so this is autosomal recessive autosomal recessive inheritance and so how do you make the diagnosis you don't obviously do a liver biopsy first off but you simply get an alpha 1-antitrypsin level and then have them see a liver doc okay so let's talk about next the characteristics of cholestatic liver disease and for that join me for the next lecture number four

5 comments

  1. Thanks for watching. See the rest of this course free here: https://www.medcram.com/courses/the-liver-explained-clearly

  2. What does it mean when someone eats a lot of red meat, their kidney starts to ache.. is this something possibly serious

  3. in november i have my resident examn hopefylly for surgery, thanks for your videos , hope you can complete do some videos about endocrine system, whatever topic that you want and thanks again for your video, greetings from mexico

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