ESR Increases or Decreases

Question 1

Inflammatory and infectious conditions

Answer 1

HIGH ESR

It increases acute-phase reactants (e.g., fibrinogen, globulins), which reduce the negative charge on RBCs, promoting rouleaux formation (RBC stacking).

This increases the mass of RBC clusters, causing them to settle faster and raising ESR.

Question 2

Autoimmune Diseases (Rheumatoid arthritis, systemic lupus erythematosus, polymyalgia rheumatica, giant cell arteritis)

Answer 2

HIGH ESR

These diseases trigger chronic inflammation, leading to an increase in fibrinogen, immunoglobulins, and other acute-phase reactants. This enhances rouleaux formation, causing a faster ESR.

Question 3

Tissue Damage and Necrosis (Myocardial infarction, malignancies like multiple myeloma)

Answer 3

It releases inflammatory cytokines, stimulating the liver to produce fibrinogen and globulins, which promote RBC aggregation. This speeds up sedimentation, increasing ESR.

In multiple myeloma, excessive monoclonal immunoglobulins (especially IgM and IgG) increase blood viscosity and promote rouleaux, significantly elevating ESR.

Question 4

Pregnancy

Answer 4

Higher fibrinogen levels during pregnancy promote RBC stacking, increasing ESR.

Question 5

Anemia

Answer 5

Fewer RBCs in the blood mean less interference in the sedimentation process, allowing RBCs to settle faster, increasing ESR.

Question 6

Polycythemia (Increased RBC count)

Answer 6

More RBCs increase blood viscosity, creating more resistance to sedimentation, leading to a slower ESR. The higher RBC concentration reduces plasma volume, limiting the effect of fibrinogen and other proteins in promoting rouleaux formation.

Question 7

Sickle Cell Anemia and Spherocytosis

Answer 7

Sickle cells and spherocytes have abnormal shapes that disrupt rouleaux formation, preventing RBCs from stacking properly. This slows sedimentation, leading to a lower ESR.

Question 8

Hypofibrinogenemia (Low fibrinogen levels)

Answer 8

Fibrinogen is crucial for rouleaux formation. When fibrinogen is low, RBCs maintain their negative surface charge, repelling each other and settling more slowly, resulting in a decreased ESR.

Question 10

• A single small RBC has a high surface area relative to its weight, so it…

• In contrast, a large RBC aggregate has a smaller surface area relative to its weight, so it…

Answer 10

falls slowly, leading to a lower ESR.

settles faster, increasing ESR.

Question 11

Iron deficiency anemia → More microcytes →

Answer 11

Lower ESR

Microcytes have less mass, making them less affected by gravity.

They have a high surface area-to-weight ratio, causing more resistance in plasma, leading to slower sedimentation.

Question 12

Megaloblastic anemia → More macrocytes →

Answer 12

Higher ESR

Large RBCs (macrocytes) settle more quickly, leading to a higher ESR.