Direct Antiglobulin Test (Coombs Test)
About this topic
The Direct Antiglobulin Test (DAT), also known as the Coombs test, is a serological assay used to detect antibodies or complement proteins attached to the surface of red blood cells. This topic is essential for tertiary students in Zambia studying hematology, immunology, or medical laboratory science. It covers the principle, procedure, clinical indications, and interpretation of DAT in diagnosing autoimmune hemolytic anemia, hemolytic disease of the newborn, and drug-induced immune hemolysis. Understanding DAT helps learners differentiate between immune and non-immune hemolytic disorders, supporting accurate diagnosis and patient management. Mastery of this test is crucial for examination preparation and professional practice in Zambian hospitals and diagnostic laboratories. The topic aligns with international hematology standards and prepares students for certification and career advancement in clinical pathology and transfusion medicine.
What you'll practise (24 questions)
- Autoimmune hemolytic anemia is often diagnosed using the direct Coombs test, which detects antibodies or complement proteins on the surface of red blood cells. True or False?
- The direct antiglobulin test (DAT) is also known as the indirect Coombs test. True or False?
- What does a positive Direct Antiglobulin Test (DAT) indicate?
- A positive Direct Antiglobulin Test (DAT) can be found in which of the following conditions?
- A patient with a positive Direct Antiglobulin Test (DAT) due to warm autoimmune hemolytic anemia would most likely have which type of antibody coating their red cells?
- In a patient with suspected transfusion reaction, a positive DAT on a post-transfusion sample but negative on a pre-transfusion sample suggests:
- What is the main purpose of performing a 'elution' test in serology?
- In a patient with a positive Direct Antiglobulin Test (DAT) due to a drug, the antibody is typically directed against the drug itself, not the red cell. True or False?
- In the evaluation of a positive Direct Antiglobulin Test (DAT), a 'warm' eluate that reacts with all panel cells suggests:
- A 'paroxysmal cold hemoglobinuria' (PCH) is associated with which autoantibody?
- Describe the Direct Antiglobulin Test (DAT) including its principle and clinical applications.
- The Direct Antiglobulin Test detects antibodies coated on red cells in vivo. True or False?
- The direct antiglobulin test (Coombs test) detects antibodies bound to red blood cells.
- What is the name of the test that uses antihuman globulin to detect antibodies or complement coating red blood cells?
- This test is performed to detect Human IgG antibodies or components of complement, eg anti-C3d, attached to red cell surface after in vivo sensitization.
- Current antiglobulin reagent (Coombs reagent) preparations contain a 'cocktail' of monoclonal antibodies directed against human?
- What is the other name for the Direct Coombs test?
- What is the importance of Coombs control cells in compatibility testing?
- True or False: The Direct Antiglobulin Test (Coombs Test) detects antibodies attached to red blood cells.
- A positive Direct Antiglobulin Test (DAT or Direct Coombs' Test) indicates that red blood cells are already coated with antibodies or complement proteins inside the patient's body.
- Which of the following is the most common cause of a false-positive Direct Antiglobulin Test (DAT) in a hospitalized patient?
- The Coombs' test is another name for the Direct Antiglobulin Test (DAT).
- A 'positive indirect antiglobulin test' (IAT) indicates the presence of free antibodies in the patient's serum that are capable of binding to red blood cells.
- The 'direct antiglobulin test' (DAT) detects antibodies that are bound to red blood cells in the patient's circulation.
Answer each question above to see the correct answer and a full explanation.