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Microcytic, normocytic, and macrocytic anemias

Video transcript

so we said that there are lots of different types of anemias then the enemies can be grouped up into two can be divided up into two large groups into into one group called the the under-production anemias and and the second group called the called a destruction anemias and the under-production anemias are anemias that are due to a problem with making the red blood cell so somewhere along the way there's a problem with making enough red blood cells versus with destruction anemias you have healthy red blood cells being made in sufficient quantities but these red blood cells are subsequently being destroyed either by your immune system by viruses or they're being lost in some way so we said that one of the ways that we can tell whether we're looking at an under production anemia or a destruction anemia is to look at the reticulocyte count where the reticulocyte count is a measure of how many reticulocytes we have and reticulocytes are young immature red blood cells right so with the destruction anemia as we said that the reticulocyte counter I'm just going to abbreviate that we take right so retic count is is higher so it's greater than 3% with 3% being the normal reticulocyte count so the destruction anemias the reticulocyte count is greater than 3% and that's indicative of a bone marrow that's working really hard to replace the lost red blood cells okay so it's turning out these young immature red blood cells to replace the ones that have been lost to destruction now compare that with the under-production anemias where the reticulocyte count is lower so it's less than the normal 3% and that's because we have in with under-production anemias we have a problem with making red blood cells so you're not going to see a bone marrow that's appropriately responding by increasing red blood cell production right because to begin with the problem is a production in red blood cells so initially the anemias are split up into under-production anemias and destruction anemias now these under-production anemias we set there are many different causes of under-production anemias these can be further sub classified based on the size of the red blood cell so before we go into any more def about that let's let's take a sight to say that the normal size of a red blood cells is measured by an index called the MC V where MC V stands for mean corpuscular volume so mean the average volume of a red blood cell and the average MC v the normal MC v range is between 80 and 100 so a normal red blood cell falls anywhere between 80 and 100 now the under-production anemias can be sub classified into anemias where the red blood cells are larger than normal are smaller than normal and our normal size okay so let's let's talk about the first group where the red blood cells are larger than normal so in that case the MCV would be greater than a hundred right because 100 is the upper limit of normal and these anemias are called the macro called a macro siddik macrocytic anemia where macro means large and siddik means cells so these are large cell large red blood cell anemia the second group where the red blood cells are smaller than normal right we'd expect to see the MCV the mean corpuscular volume less than 80 because 80 is a lower end of normal right and these in use these are called the micro citic anemias microcytic anemias micro meaning small city meaning cells so these are small red blood cell anemia and then finally the group of normal size of red blood cells oils that's the MCV of those cells falls between eighty and a hundred right so right within the normal range and these are called normal acidic anemias so normal sell normal red blood cell size anemias and we're going to go into the different causes of macrocytic microcytic and normocytic anemias the different types of those anemias but as a general rule of thumb the macrocytic anemia are caused by a shortage of DNA precursors so anything that causes a shortage of DNA precursors will lead to a macrocytic anemia okay compare that to a microcytic anemia a general rule of thumb is Mike microcytic anemias are caused by a shortage of hemoglobin right impaired hemoglobin production whether that's not enough hemoglobin being formed or abnormal hemoglobin formed whatever the cause there's an there's a problem with making hemoglobin whenever you have a problem with making hemoglobin that leads to a microcytic anemia and pretty much all of the other under-production anemias fall into the realm of the normal setting yes okay so we're going to go again we're going to go into specifics about the different types of anemias but this is this this diagram is a very good paradigm into organizing your thinking about the different types of anemias and as we go along it's important to sort of place the anemias where they fall within this diagram because it helps you to keep them keep them organized in your mind