Test Code LAB4187 SEDIMENTATION RATE
Specimen Type
EDTA Whole Blood (Lavender Top Tube)
Specimen Volume
4 mL
Minimum Volume
1.5 mL
Turnaround Time
STAT: 1 hour
Routine: 4 hours
Test Schedule
Daily
Sample Stability
Refrigerated/Room Temperature: 24 hours
Reference Ranges
Sed Rate mm/h
Male 0-15
Female 0-25
Synonyms
ESR; Erythrocyte Sedimentation Rate
CPT Codes
85652
Test Components
Sed Rate, mm/h.
Clinical Information
Erythrocyte sedimentation rate (ESR) is the rate in millimeters per hour that red blood cells (RBC) settle out of plasma in anticoagulated whole blood. The rate of RBC settling is affected by three factors:
- Red blood cell number, shape, and size
- Mechanical and technical factors (e.g., temperature, tube diameter, bubbles, etc.)
- Plasma factors
The presence of fibrinogen, alpha-2-globulin, beta, and gamma globulins decreases the red blood cell zeta potential, promoting rouleaux which results in a faster sedimentation rate. The ESR thus reflects changes in plasma proteins which accompany acute and chronic infections, inflammation, malignancy, multiple myeloma, macroglobulinemia and hyperfibrinogenemia. It is used primarily to follow the progress of inflammatory diseases such as rheumatoid arthritis during treatment.