Thank you for donating blood through the American Red Cross. During the blood donation process, samples are collected and sent to a laboratory where they undergo routine screening and infectious disease testing. For a limited time, the Red Cross is also screening donations from self-identified multiracial and Black or blood donors for hemoglobin S, a key indicator of sickle cell trait.
Sickle cell trait is inherited, and many individuals are not aware that they carry this trait. Sickle cell trait is not sickle cell disease. Many who carry the trait will have no medical conditions related to sickle cell disease.
A screening test is a preliminary test used to detect the presence of a marker for a condition. The screening test we perform does not diagnose sickle cell disease but it may provide our donors with valuable insights into their health status.
Positive result: Indicates that the screening test detected the presence of Hemoglobin S or sickle hemoglobin, which may mean you carry the sickle cell trait. These results are a preliminary screening. The Red Cross recommends that you consult your medical provider to discuss your test results and pursue additional testing. Those who receive a positive result will also receive a letter in the mail.
It is important to note that carrying the sickle cell trait does not mean that an individual has sickle cell disease. In general, individuals who carry the sickle cell trait have no medical conditions related to sickle cell disease.
Negative result: Indicates that the screening test did not detect the presence of Hemoglobin S or sickle hemoglobin. This means that the individual is likely not a sickle cell trait carrier. It is important to note that the Red Cross is not screening for other abnormal hemoglobin cells that can also cause sickling, such as Hemoglobin. If you have a family history of other hemoglobin conditions, you may want to consult your medical provider.
Inconsistent result: Indicates that the Red Cross is unable to confirm a positive or negative screening result. In some cases, this is because the Red Cross testing laboratory may have previously screened a donor for sickle cell trait at a hospital request to fulfill a specific product need for a patient. In some cases, the donor may have received a prior notification of a positive result. While the Red Cross will work to resolve many inconsistent results, a portion may remain inconsistent.
Not Tested result: While rare, some donations may not be able to be tested due to processing issues. Donors will need to have a successful donation to receive sickle cell trait screening results. Per standard procedures, only successful donations are sent to our laboratory for testing.
For more information about sickle cell trait, you can visit the Sickle Cell Disease Association of America website.
For additional information about your test result, you may download or view the manufacturer’s fact sheet for the Pacific Hemostasis® Sicklescreen® Sickling Hemoglobin Screening Kit or Streck Sickledex® Solubility Testing Kit.