Coombs Direct Blood Test
Coombs Direct (Direct Antiglobulin DAT) Test
The Coombs Direct, or Direct Antiglobulin Test (DAT), looks for antibodies that attack red blood cells. When the body's immune system identifies red blood cells that do not match your blood type, it produces antibodies to attack these foreign cells. This can be a result of receiving a blood transfusion where the donor's blood type is not a perfect match for yours. A condition known as Autoimmune Hemolytic Anemia can also cause the body to attack its own red blood cells. Diseases such as lupus, leukemia, mycoplasma pneumonia, and mononucleosis can cause autoimmune hemolytic anemia. Some medications such as penicillin and other types of antibiotics can also cause the body to begin producing antibodies against red blood cells.
It is important to note that while the Coombs Direct test can identify if there are antibodies attacking your red blood cells, it cannot determine why. Consultation with your doctor and follow-up testing will usually be necessary.
A direct antiglobulin test (DAT) is typically ordered when a person is experiencing symptoms such as dizziness, shortness of breath, back pain, headaches, paleness, and dark-colored urine, especially if they have recently received a blood transfusion. The coombs direct blood test may be ordered for someone with an autoimmune disorder who is experiencing anemia symptoms.
Turnaround for the Coombs Direct test is typically 2-3 business days.