Overview: D-Dimer Quantitative TestIntroduction: The D-Dimer Quantitative Test measures D-dimer to diagnose blood clotting disorders, causing swelling or chest pain due to clots. Aligned with 2023 ASH guidelines, it uses an immunoassay for high sensitivity, aiding in coagulation screening. This test is critical for guiding diagnosis, treatment, and improving outcomes in immunology for patients with suspected clotting disorders like DVT or PE.
Other Names: D-Dimer Quant Assay, Fibrin Degradation Test.
FDA Status: Laboratory-developed test (LDT), meeting immunology standards for diagnostic accuracy.
Historical Milestone: D-dimer testing began in the 1980s with coagulation research. Quantitative immunoassays emerged in the 1990s, and by the 2000s, high-sensitivity assays improved accuracy.
Purpose: Diagnoses clotting disorders, guides anticoagulant therapy, and monitors D-dimer levels in patients with swelling or chest pain.
Test Parameters: 1. D-Dimer
Pretest Condition: No fasting required. Collect plasma at any time. Report symptoms like swelling or chest pain, and list medications like anticoagulants.
Specimen: 2-4 mL plasma (NaCit). Centrifuge within 1 hour. Transport in a biohazard bag within 8 hours.
Sample Stability at Room Temperature: 8 hours
Sample Stability at Refrigeration: 7 days
Sample Stability at Frozen: 6 months
Medical History: Document swelling, chest pain, or history of clotting disorders (e.g., DVT, PE). Include current medications, especially anticoagulants.
Consent: Written consent required, detailing the tests purpose, diagnostic implications, and potential need for anticoagulant therapy.
Procedural Considerations: Uses an immunoassay (e.g., ELISA) to measure D-dimer levels. Results are available in 1-2 days, enabling rapid clinical decisions.
Factors Affecting Result Accuracy: Recent surgery, trauma, or inflammation can elevate D-dimer levels. Hemolysis may degrade samples.
Clinical Significance: Elevated D-dimer levels suggest clotting disorders, prompting imaging or anticoagulant therapy. Normal levels may rule out DVT/PE in low-risk patients.
Specialist Consultation: Consult a hematologist or cardiologist for result interpretation.
Additional Supporting Tests: Doppler ultrasound, CT pulmonary angiography, or coagulation panel to confirm clotting disorders.
Test Limitations: Non-specific elevations may occur in non-clotting conditions. Results require clinical correlation.
References: ASH Coagulation Guidelines, 2023; Journal of Thrombosis and Haemostasis, Weitz JI, 2022.
