Sedrate, Automated

On June 1, 2017, VA BHS switched to a new assay for Erythrocyte Sedimentation Rates (ESR) using the iSED analyzer. The iSED uses advanced Rheology technology which captures the most critical phase of RBC sedimentation which is the rouleaux formation. In this technology, the size of red blood cell aggregates is directly proportional to the ESR value which increases according to the presence and intensity of inflammation. The iSED directly measures the aggregation of red blood cells while the traditional ESR measures it indirectly.
 
The iSED is less affected by conditions commonly associated with the traditional ESR testing, the most important of which is hemocrit. This explains the differences that can be seen when comparing results of the iSED with another Westergren or modified Westergren methodology. Patients undergoing serial ESR testing over time should have new baselines established.
 
Phlebotomy and specimen processing changes to note with the new methodology:

• The specimen will need to be collected in a standard lavender (k2EDTA) tube.
• The test is ordered as ESR (erythrocyte sedimentation rate)
• The minimum volume is 1 ml.
• The new test code to order is SEDRATE,AUTOMATED

Benefits of the new assay:

• The tests can be completed in less than 4 minutes.
• Testing is completed from the primary EDTA tube.
• The test can be completed on less than 1 ml.
• iSED ESR is less affected by hematocrit and gives a more accurate indication of patient inflammation.

SEDRATE, AUTOMATED

ESR
Erythrocyte sedimentation rate
Sed Rate
Hematology

Whole blood lavender EDTA

1 mL

Refrigerated

Room temperature: 24 hours
Refrigerated (2-8°C): 24 hours

Age	Gender	Reference range	Units
< 51	Male	0 - 15	mm/hr
> 50	Male	0 - 20	mm/hr
< 51	Female	0 - 20	mm/hr
> 50	Female	0 - 30	mm/hr

Useful in differentiating inflammatory and neoplastic diseases and as an index of disease severity.
Patients with polycythemia and many hemoglobin abnormalities may have depressed sed rates whereas patients with anemia may have elevated sed rates.