Coombs test

A blood sample is needed.

No special preparation is necessary for this test.

When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or slight bruising. This soon goes away.

There are two types of the Coombs test: Direct Indirect The direct Coombs test is used to detect antibodies that are stuck to the surface of red blood cells. Many diseases and medicines can cause this to happen. These antibodies sometimes destroy red blood cells and cause anemia . Your health care provider may…

A normal result is called a negative result. It means there was no clumping of cells and you have no antibodies to red blood cells. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your…

An abnormal (positive) direct Coombs test means you have antibodies that act against your red blood cells. This may be due to: Autoimmune hemolytic anemia Chronic lymphocytic leukemia or similar disorder Blood disease in newborns called erythroblastosis fetalis (also called hemolytic disease of the newborn) Infectious…

There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others. Other risks associated with having blood drawn are slight, but may include: Fainting…

Elghetany MT, Banki K. Erythrocytic disorders. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods . 24th ed. Philadelphia, PA: Elsevier; 2022:chap 33. Michel M. Autoimmune and intravascular hemolytic anemias. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine . 27th…