| • | erythrocyte sedimentation rate |
| • | measures the distance that erythrocytes have fallen after one hour in a vertical column of anticoagulated blood under the influence of gravity |
| • | the amount of fibrinogen (an acute phase reactant) in the blood, directly correlates with the ESR |
| • | any condition that elevates fibrinogen, may elevate ESR: pregnancy, DM, ESRD, CTD, malignancy, heart disease |
| • | anemia and macrocytosis increase ESR (with the hematocrit reduced, the velocity of the upward flow of plasma is altered so that RBC aggregates fall faster) |
| • | ESR remains an important diagnostic criterion for only two diseases: polymyalgia rheumatica and temporal arteritis |
| • | may also help to distinguish inflammatory from non-inflammatory disease (e.g. in patients presenting with polyarthritis) |
| • | ESR remains an appropriate measure of disease activity or response to therapy for only a few diseases: temporal arteritis, polymyalgia rheumatica, RA, and possibly acute rheumatic fever |
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