Erythrocyte sedimentation rate Old, well-established acute phase reactant Measures the distance that erythrocytes have fallen after one hour in a vertical column of anticoagulated blood (measured in mm/hr) Primarily affected by fibrinogen
What is CRP?
C-reactive protein Acute phase protein synthesized by the liver Part of the innate immune system
5 positive acute phase reactants (apart from CRP and ESR)
Ferritin Procalcitonin (specific for infection) Fibrinogen Alpha-1 antitrypsin Haptoglobin
3 negative acute phase reactants
Albumin Transferrin Transthyretin
What are the advantages of ESR?
Better established Cheaper (therefore more widely available)
What are the advantages of CRP?
More sensitive More specific More responsive to changes in inflammatory state
What are 2 conditions that elevate ESR in the absence of an inflammatory state?
What are 2 conditions that depress ESR?
Polycythaemia rubra vera Leukocytosis
What are the 4 conditions that must be considered in a patient with an extremely elevated ESR (>100)?