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Hereditary Spherocytosis Evaluation (New test)
|Method||Osmotic lysis and flow cytometry|
|Patient Preparation||Recent transfusion, oral contaceptive use and H2 blocker use may interfere with test results.|
|Collection Instructions||A control specimen is required from an unrelated, normal, non-smoking individual. Draw control at the same time as the patient sample. Clearly mark the control sample with 'CONTROL' and the sex of the individual providing the control sample on the label.
Refrigerate samples immediately after collection and transport cold to the lab.
|Container type||Lavender top|
|Amount to Collect||5 mL blood|
|Sample type||EDTA Whole blood|
|Preferred volume||5 mL blood|
|Min. Volume||2 mL blood|
|Processing notes||Refrigerate immediately after collection. Maintain refrigerated and transport both patient sample and control sample to CB. Order Mayo test code HSEP.|
|Ref Lab Rejection Criteria||Samples received > 96 hours after collection|
|Units||% hemolysis and interpretive report|
|Normal range|| 0.50 g/dL NaCl (unincubated)
0.60 g/dL NaCl (incubated)
0.65 g/dL NaCl (incubated)
0.75 g/dL NaCl (incubated)
|Synonyms||HS; ektacytometry; EKTA; hemolytic anemia; spherocytes; Red Cell Osmotic fragility|
|Stability||Refrigerated 4 days|
|Turn around times||4-7 days|
|Reflex?||If indicated based on osmotic lysis results flow cytometry is performed as an additional step in the evaluation and charged separately|
|Additional information||The hemolytic anemias are a group of anemias that are characterized by an increased destruction of RBCs. Anemias may be divided into inherited or acquired. Hereditary spherocytosis (HS), also known as congenital hemolytic anemia, is inherited as a non sex-linked dominant trait. HS is caused by a RBC membrane defect. The RBCs are spherocytic in shape and show an increased rate of destruction. HS can result from abnormalities involving several red cell membrane proteins, such as band 3, spectrin, and ankyrin.
Most often HS is diagnosed in childhood, adolescence, or early adult life. The diagnosis of HS is usually made by a combination of patient and family history, laboratory evidence of hemolysis, and review of a peripheral blood smear. The osmotic fragility test is usually markedly abnormal in these cases. However, factors such as age, sex, and medications can affect the osmotic fragility test.
This evaluation combines osmotic fragility testing with a newly developed flow cytometry assay to provide complementary information in the evaluation of patients with suspected HS.
|CPT coding||85557-90, 88184-90|
|Last Updated||6/5/2013 11:57:51 AM|
If you have additional questions regarding this test, please call: 415-353-1667