Direct Antiglobulin Test (DAT) with Reflex to Anti

The Direct Antiglobulin Test (DAT) with Reflex to Anti test contains 1 test with 1 biomarker.

Brief Description: The Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG is a specialized blood test used to determine if antibodies or complement proteins are attached to the surface of red blood cells, which may cause the cells to be destroyed prematurely. The test initially carries out a Direct Antiglobulin Test, and if positive, it reflexes to additional testing for Anti-C3 and Anti-IgG to identify which specific substances are bound to the red blood cells.

IMPORTANT - NOTE THIS IS A REFLEX TEST AND AN ADDITIONAL CHARGE OF $64 WILL OCCUR IF THE QUEST RUNS THE REFLEX TEST.

If DAT (Coombs, Direct) is positive, Anti C3d and Anti IgG will be performed at an additional charge of $64.00

Collection Method: Blood Draw

Specimen Type: Whole Blood

Test Preparation: No preparation required

When and Why a Direct Antiglobulin Test with Reflex to Anti-C3 and Anti-IgG May Be Ordered

This test is typically ordered when a person has signs or symptoms of hemolytic anemia or jaundice, which may be caused by the immune system attacking red blood cells. Symptoms may include fatigue, weakness, jaundice, and a rapid heart rate among others. The test is crucial in diagnosing and understanding the cause of hemolysis and in monitoring the conditions known to cause immune hemolysis.

What a Direct Antiglobulin Test with Reflex to Anti-C3 and Anti-IgG Checks For

The Direct Antiglobulin Test looks for antibodies and complement proteins bound to red blood cells. If the DAT is positive, it implies there are such substances on the red blood cells, triggering their premature destruction. The reflex testing for Anti-C3 and Anti-IgG identifies whether immunoglobulins, complement components, or both are present. This distinction can be pivotal in diagnosing the cause of hemolysis.

Other Lab Tests Ordered Alongside Direct Antiglobulin Test with Reflex to Anti-C3 and Anti-IgG

When a DAT is ordered, it's usually part of a broader evaluation of hemolysis or immune-related hemolytic anemia. Here are some tests commonly ordered alongside it:

1. Complete Blood Count (CBC) with Reticulocyte Count:

   • Purpose: To evaluate overall blood health, including RBC count, hemoglobin levels, and reticulocyte count (immature RBCs).
   • Why Is It Ordered: To assess for anemia and the body's response to RBC loss through increased production of reticulocytes.

2. Lactate Dehydrogenase (LDH):

   • Purpose: To measure the level of LDH, an enzyme that can be elevated in the blood when there is tissue damage or hemolysis.
   • Why Is It Ordered: To support the diagnosis of hemolysis, as LDH is often elevated when RBCs are destroyed.

3. Bilirubin (Total and Direct):

   • Purpose: To measure the levels of bilirubin, a byproduct of RBC breakdown.
   • Why Is It Ordered: To assess for increased RBC destruction, which can lead to elevated levels of indirect (unconjugated) bilirubin.

4. Haptoglobin:

   • Purpose: To measure haptoglobin, a protein that binds free hemoglobin.
   • Why Is It Ordered: To evaluate for hemolysis, as haptoglobin levels decrease when it binds to the free hemoglobin released from destroyed RBCs.

5. Iron Studies:

   • Purpose: To assess iron status.
   • Why Is It Ordered: To evaluate the body's iron stores and iron-binding capacity, which can be affected in chronic hemolytic anemias.

6. ANA:

   • Purpose: To detect the presence of autoantibodies that can indicate autoimmune disorders.
   • Why Is It Ordered: To identify underlying autoimmune conditions that may cause or contribute to hemolytic anemia.

These tests, when ordered alongside a Direct Antiglobulin Test, provide a comprehensive evaluation of hemolytic anemia and its potential causes. They are crucial for diagnosing the type of hemolysis, assessing its severity, identifying underlying conditions, and guiding appropriate treatment strategies. The specific combination of tests will depend on the individual’s symptoms, clinical presentation, and initial test results.

Conditions or Diseases Requiring Direct Antiglobulin Test with Reflex to Anti-C3 and Anti-IgG

Conditions that may require a DAT with Reflex to Anti-C3 and Anti-IgG include autoimmune hemolytic anemia, in which the body's immune system mistakenly targets and destroys its red blood cells. Other diseases might include hemolytic disease of the fetus and newborn (HDFN) or transfusion reactions where mismatched blood is transfused into a patient.

How Health Care Providers Use the Results of a Direct Antiglobulin Test with Reflex to Anti-C3 and Anti-IgG

Healthcare providers use the results of this test to diagnose and monitor autoimmune hemolytic anemia and other conditions related to immune-mediated hemolysis. If the DAT is positive, and either Anti-C3 or Anti-IgG or both are detected, it supports a diagnosis of immune-mediated hemolytic anemia. Depending on the findings, healthcare providers can develop a treatment plan, which may include immunosuppressive therapy, blood transfusions, or other targeted treatments to manage the condition and alleviate symptoms. Furthermore, it helps in understanding the severity of the hemolysis and in monitoring the efficacy of the treatment over time.

Most Common Questions About the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG:

Purpose and Clinical Indications

What is the primary purpose of the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG?

The primary purpose of the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG is to detect the presence of antibodies or complement proteins bound to the surface of red blood cells (RBCs). This test is critical in diagnosing and managing conditions like autoimmune hemolytic anemia (AIHA), where the immune system mistakenly targets and destroys RBCs. The reflex testing with Anti-C3 and Anti-IgG can further elucidate whether the immune response is triggered by the complement system or by immunoglobulin G antibodies, which can be informative for diagnosis and treatment planning.

Why is the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG ordered by healthcare providers?

The Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG is ordered by healthcare providers when there's a suspicion of hemolytic anemia, especially of autoimmune origin, or other hemolytic disorders. Symptoms such as jaundice, dark urine, fatigue, and anemia may trigger the need for this test. The reflex testing to Anti-C3 and Anti-IgG can provide additional insights into the underlying immune mechanisms causing the hemolysis, which can be crucial for accurate diagnosis and appropriate treatment.

Interpretation of Results

How are the results of the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG interpreted?

The results of the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG are interpreted based on whether or not antibodies or complement proteins are detected on the surface of red blood cells. A positive result indicates the presence of these immune molecules on RBCs, suggesting an immune-mediated hemolytic process. The reflex tests to Anti-C3 and Anti-IgG help identify which immune molecules are involved - whether it’s complement proteins, IgG antibodies, or both. This information is vital for diagnosing specific types of hemolytic anemia and can guide the subsequent management and treatment plans.

What do positive results in the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG signify?

Positive results in the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG signify an immune-mediated process where antibodies and/or complement proteins are bound to the surface of red blood cells, leading to their premature destruction. This is typically seen in autoimmune hemolytic anemias. The reflex tests to Anti-C3 and Anti-IgG further specify which arm of the immune system is predominantly involved, whether it's antibody-mediated, complement-mediated, or both. This differentiation can be critical for understanding the underlying pathology and guiding treatment.

Clinical Implications

How might the results of the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG influence the treatment plan for patients?

The results of the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG can significantly influence the treatment plan for patients. Identifying the immune mechanism causing hemolysis guides the choice of therapeutic interventions. For example, treatments may include immunosuppressive drugs, intravenous immunoglobulin (IVIG), or other modalities aimed at suppressing or modulating the immune response. Accurate identification of the underlying immune mechanism through reflex testing to Anti-C3 and Anti-IgG can enable more targeted and effective treatment strategies.

How often should an individual with autoimmune hemolytic anemia undergo the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG?

The frequency with which an individual with autoimmune hemolytic anemia should undergo the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG depends on the specific clinical scenario and the treating physician’s judgement. It might be done at diagnosis, during treatment to assess response, or if there's a suspected relapse of disease. It’s critical to work closely with healthcare providers who can provide personalized advice based on the individual’s disease course and response to treatment.

Relationships with Other Conditions

Can the results of the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG indicate other health conditions?

While the primary focus is on detecting autoimmune hemolytic processes, the results of the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG can also indicate other conditions. For instance, a positive DAT can be seen in drug-induced hemolytic anemia, infection-related hemolysis, or hemolytic disease of the newborn. Additionally, certain systemic autoimmune or inflammatory conditions might have secondary hemolytic anemia as a complication, which could be detected through this test.

How can the Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG be utilized in conjunction with other diagnostic tests?

The Direct Antiglobulin Test (DAT) with Reflex to Anti-C3 and Anti-IgG can be used in conjunction with other diagnostic tests such as a complete blood count (CBC), reticulocyte count, and other hemolysis-related lab tests to provide a comprehensive understanding of the hemolytic process. Furthermore, additional immunological testing, such as the indirect antiglobulin test (IAT) or tests for specific autoantibodies, may also be performed to gather more information about the immune status of the individual. By integrating the results of the DAT with other diagnostic data, healthcare providers can formulate a more accurate diagnosis and a more effective treatment plan.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.