| Identifier |
esr_for_ophthalmology_lee |
| Title |
Erythrocyte Sedimentation Rate (ESR) for Ophthalmology |
| Creator |
Andrew G. Lee, MD; Christine Tang |
| Affiliation |
(AGL) Chairman, Department of Ophthalmology, The Methodist Hospital, Houston, Texas; Professor of Ophthalmology, Weill Cornell Medicine, New York City, New York; (CT) Class of 2023, Baylor College of Medicine, Houston, Texas |
| Subject |
ESR; Red Blood Cells |
| Description |
Summary: • Erythrocyte sedimentation rate (ESR) - rate in mL/hr of erythrocyte sedimentation o From the 1800s o How fast red blood cells (RBCs) sediment in a tube over an hour, in millimeters • Normal sedimentation rate o RBCs have a charge, and a potential is generated by that charge that keeps the RBCs apart because the charges repel o This negative charge = zeta potential • Created by sialic acid residues on the surface of RBC membranes • Useful because RBCs have to pass single-file through capillary beds o RBCs do not clump together because their charges repel • Abnormal (increased) sedimentation rate o Something is decreasing the zeta potential, allowing RBCs to collect into the Rouleaux formation in a test tube • Rouleaux formation = stack of RBCs, like a stack of coins • Problems/processes that may cause increased sed rate o Inflammatory, infectious, neoplastic malignancy (i.e. multiple myeloma) • Inflammation of any kind -> release acute phase reactants (i.e. c-reactive protein, increased platelet count) o Good to order C-reactive protein, platelet count in addition to the ESR to make an informed clinical decision o Age and Gender • Proteins accumulate in blood as we age • Empiric formula o For women: (age + 10)/2 o For men: age/2 • 40 is too high for an older patient • Consider testing ESR for any older patient with a neuro-ophthalmic symptom o Neuro-ophthalmic problems (esp. in elderly) • Giant cell arteritis • Vision loss/double vision • Amaurosis fugax • Etc. • ESR is not specific o Renal failure o Diabetes o Inflammation/infection o Neoplastic malignancy (I.e. multiple myeloma) o Can have normal ESR rate but still have giant cell arteritis. |
| Transcript |
So today I'm going to be talking about the erythro sediment. The erythrocyte sedimentation rate but for ophthalmologists. It is the rate in millimeters per hour of the sedimentation of the erythrocyte, so how fast do these red blood cells sediment in a tube over an hour in millimeters. It's a very simple test; it's from the 1800s. In fact it is not very technical. Look at the tube, you look at the tube again, you measure how much the sedimentation rate was. And the thing that prevents red cells from sedimenting, the reason your sed rate is normal presumably, and there's only two millimeters per hour, and a patient with giant cell arteritis sed rate is a hundred millimeters per hour. The reason that difference occurs is because the red cells actually have a charge, and a potential is generated by that charge that keeps the red cells apart because like charges repel. And so that negative potential, it is called the zeta potential. That zeta potential is created by sialic acids residues on the surface of the red cell membrane that keep the red cells apart and we need that because when we're passing through the capillary bed, we really have to have small enough single-file to get the red cells to pass through there one at a time. And we really have to have them spaced out, really can't have them all clumping together. So when you have a sedimentation rate that is increased, that means something, you don't know what, is decreasing the zeta potential and allowing the red cells to collect together, and when they collect together, they found-form this kind of stack of coins which is the Rouleaux formation. So when that stack of coins occurs, of course that whole column is gonna fall to the bottom and that is what is the increased sedimentation rate. And the reason you need to notice in ophthalmology is it's not just about giant cell arteritis. So if you have inflammation of any kind, acute phase reactants are going to be released: for example c-reactive protein but also the platelet count those proteins in response to any kind of disorder, inflammatory, infectious and neoplastic malignancy would block the charge. The red cells will aggregate, the Rouleaux formation will occur, and your sedimentation rate will go up. You should know that the sedimentation rate goes up with just age because there's all sorts of proteins that are building up in your bloodstream as you get older. And so the empiric formula that we use for sedimentation rate is age plus 10 divided by 2 for women, and for men we just age divided by 2. So the normal sedimentation rate is age and gender dependent. These are just empiric formulas. If you can't remember any single number, 40. 40 is kind of like too high for an older patient. And so we're relying upon the sedimentation rate to tell us that we have something wrong with us, and the reason it's important in ophthalmology is any elderly patient who has any neuro-opthalmic symptom, you want to consider doing a sedimentation rate. It doesn't tell you what's wrong with the person but it tells you something is wrong with the person, and that something could be giant cell arteritis. You also need to know that the sedimentation rate is not specific. If it's elevated it might be renal failure from those proteins glomming under the red cell membrane. It might be diabetes with sugar glomming onto the red cell membrane. It could be malignancy, it could be infection/inflammation. You don't know what is causing this elevated sed rate and so you have to be thinking about other conditions. Neoplastic conditions like multiple myeloma often raise the sedimentation rate so said rate by itself does not mean you have done something. And the reverse, you could have a totally normal sedimentation rate and still have giant cell arteritis because it requires the systemic inflammatory response and reduction in the zeta potential that might not occur if the disease is only right here. So an ophthalmologist needs to know about the rate of sedimentation for erythrocytes. It's usually a low number, it's age and gender specific. The higher the number, the more worrisome it is. It tells you something is wrong but not what is wrong. You should be thinking about giant cell arteritis and be doing it in every patient who's elderly who's got vision loss or double vision or amaurosis fugax or whatever they have. You're gonna order the other acute phase reactants, the C reactive protein and the platelet count to help make a clinical decision about whether this sed rate is real or not. And you know, need to know a little bit about Rouleaux and the zeta potential in ophthalmology. |
| Date |
2021-04 |
| Language |
eng |
| Format |
video/mp4 |
| Type |
Image/MovingImage |
| Collection |
Neuro-Ophthalmology Virtual Education Library: Andrew G. Lee Collection: https://novel.utah.edu/Lee/ |
| Publisher |
North American Neuro-Ophthalmology Society |
| Holding Institution |
Spencer S. Eccles Health Sciences Library, University of Utah |
| Rights Management |
Copyright 2019. For further information regarding the rights to this collection, please visit: https://NOVEL.utah.edu/about/copyright |
| ARK |
ark:/87278/s6h76cbw |
| Setname |
ehsl_novel_lee |
| ID |
1680600 |
| Reference URL |
https://collections.lib.utah.edu/ark:/87278/s6h76cbw |
