One hour after a patient’s blood sample has been placed in a test tube, the sedimentation rate (sed rate) is measured in millimeters per hour (mm/hr). This is the speed with which red blood cells in the blood settle at the bottom of the test tube.

Sed rate test results are then measured against the following normal values (which can vary slightly from lab to lab):

High sedimentation rates may indicate the following conditions or diseases:

• Cancer, especially:
  
• • Lymphoma
    
    
  • Hodgkin’s disease
    
    
  • Leukemia
    
    
  • Multiple myeloma

According to the American Academy of Family Physicians, a sedimentation rate of 100 mm/hr usually indicates cancer that has metastasized (spread to other areas of the body) in patients with solid tumors. Elevated sed rate levels may indicate early relapse in patients with Hodgkin’s disease.

• Infections, such as pneumonia, syphilis and tuberculosis
  
  
• Autoimmune diseases such as rheumatoid arthritis and lupus
  
  
• Kidney disease
  
  
• Pregnancy
  
  
• Thyroid disease
  
  
• Severe anemia

Low sedimentation rates can also signal disease or abnormality, including:

• Sickle cell anemia (in which red blood cells become crescent-shaped)
  
  
• Polycythemia (elevated production of red blood cells)
  
  
• Congestive heart failure
  
  
• Hyperviscosity (slowing of newborn’s blood flow due to excessive red blood cell count)
  
  
• Liver or kidney disease (in which production of plasma protein is decreased)
  
  
• Hypofibrinogenemia (decreased levels of fibrinogen, a blood plasma protein important to blood clotting)