Epic Test Code LAB339 Sickle Solubility, Blood
Additional Codes
MML Code: SDEX
LIS Code: SCS
NY State Approved
YesPerforming Laboratory
Mayo Clinic Laboratories in RochesterReporting Name
Sickle Solubility, BMethod Name
Hemoglobin S Solubility
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Whole Blood EDTA | Refrigerated | 14 days |
Ordering Guidance
This is a screening test only. For quantification of hemoglobin S, order HBEL1 / Hemoglobin Electrophoresis Evaluation, Blood.
Necessary Information
1. Patient's age is required.
2. Include recent transfusion information.
Specimen Required
Container/Tube:
Preferred: Lavender top (EDTA)
Acceptable: Yellow top (ACD solution B), green top (heparin)
Specimen Volume: 1 mL
Collection Instructions:
1. Invert several times to mix blood.
2. Send whole blood specimen in the original tube. Do not aliquot.
Specimen Type
Whole Blood EDTASpecimen Minimum Volume
0.5 mL
Reference Values
Negative
Report Available
1 to 4 daysDay(s) Performed
Monday through Friday
CPT Code Information
85660
Reject Due To
Gross hemolysis | Reject |
Useful For
Screening for presence or absence of hemoglobin (Hb) S (sickle cell disease)
Clinical Information
Homozygous hemoglobin (Hb) S (sickle cell disease) is a serious chronic hemolytic anemia most commonly found in those of African or Middle Eastern descent.
Hb S is freely soluble when fully oxygenated; when oxygen is removed, polymerization of the abnormal hemoglobin occurs, forming tactoids that are rigid and deformed cells. This leads to sickling of the cells, hemolysis, and many other complications.
Heterozygous Hb S (sickle cell trait) is the most common hemoglobinopathy in the United States. This condition is present in about 8% of African Americans. Usually, Hb S trait exhibits no clinical or hematological effects. A small fraction of people with sickle cell trait have recurrent hematuria.
Interpretation
A positive result should be followed by a complete hemoglobin (Hb) evaluation (HBEL1 / Hemoglobin Electrophoresis Evaluation, Blood) to confirm the presence and concentration of Hb S.
Cautions
A positive test is presumptive evidence for hemoglobin (Hb) S (sickle cell disease). However, rare sickling Hbs such as Hb C-Harlem (C-Georgetown) and Hb I will also produce a positive result.
This test only detects the presence of Hb S. It cannot differentiate sickle cell trait (heterozygous Hb S) from sickle cell disease (homozygous Hb S), or Hb S in combination with other abnormalities (eg, S/C, S/D, S/G, S/E, S/beta-thalassemia, S/O-Arab, S/New York, and C-Georgetown trait).
The use of packed red blood cells (RBC) instead of whole blood significantly reduces false negatives due to anemia and false positives due to hypergammaglobulinemia (eg, multiple myeloma).
False positives can occur due to large numbers of nucleated RBC.
False negatives can occur due to an insufficient quantity of Hb S due to age (neonates) or transfusion. Hb S concentrations 15% to 20% or less may give a negative result.
Specimen Retention Time
7 daysForms
If not ordering electronically, complete, print, and send a Benign Hematology Test Request Form (T755) with the specimen.