Mechanism and Significance of ESR

[E.S.Prakash]

Dear Sir,

Can you explain about the erythrocyte sedimentation rate? I also confused about the mechanism of sedimentation of RBCs. Then it says that in later months of pregnancy the ESR rate is more and same goes with anaemia. But in pregnnancy the RBC count should be higher right? Can you explain this?

Ravi Ruben, Year 1

Reply: 

Ravi, to your main question - please find the link (below) to a short article describing mechanism and significance of ESR.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1954390/pdf/brmedj02899-0040.pdf

Actually, while the absolute mass of RBCs increases during pregnancy, the concentration of RBCs (RBC count) actually drops because of hemodilution (relative increase in plasma volume over RBC volume). 

ESR is higher in anemia primarily because hematocrit (or packed cell volume) and the viscosity of blood are both lower but additional factors may operate. 

Prakash

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