Overview: G6PD Qualitative TestIntroduction: The G6PD Qualitative Test detects G6PD enzyme deficiency, causing anemia or jaundice after exposure to triggers. Aligned with 2023 ASH guidelines, it uses spectrophotometry for high sensitivity, aiding in hematological screening. This test is critical for guiding diagnosis, management, and improving outcomes in hematology for patients with suspected G6PD deficiency.
Other Names: G6PD Qualitative Assay, Glucose-6-Phosphate Dehydrogenase Screen.
FDA Status: Laboratory-developed test (LDT), meeting hematology standards for diagnostic accuracy.
Historical Milestone: G6PD qualitative testing began in the 1960s with hematology research. Spectrophotometry improved in the 1980s, enhancing detection accuracy.
Purpose: Diagnoses G6PD deficiency, guides trigger avoidance, and monitors enzyme activity in patients with anemia or jaundice.
Test Parameters: 1. Glucose-6-Phosphate Dehydrogenase
Pretest Condition: No fasting required. Collect whole blood at any time. Report symptoms like anemia or jaundice, and list triggers or medications.
Specimen: 2-5 mL whole blood (EDTA). Transport in a biohazard bag within 24 hours.
Sample Stability at Room Temperature: 24 hours
Sample Stability at Refrigeration: 48 hours
Sample Stability at Frozen: Not frozen
Medical History: Document anemia, jaundice, or history of G6PD deficiency. Include triggers (e.g., fava beans, drugs) and current medications.
Consent: Written consent required, detailing the tests purpose, diagnostic implications, and potential need for trigger avoidance.
Procedural Considerations: Uses spectrophotometry to detect G6PD enzyme activity. Results are available in 1-2 days, enabling rapid clinical decisions.
Factors Affecting Result Accuracy: Hemolysis or improper storage can affect results. Recent transfusions may mask deficiency.
Clinical Significance: Low G6PD activity confirms deficiency, prompting trigger avoidance. Normal results may require quantitative testing.
Specialist Consultation: Consult a hematologist for result interpretation.
Additional Supporting Tests: G6PD quantitative test, CBC, or genetic testing to confirm deficiency.
Test Limitations: False negatives may occur post-transfusion. Results require clinical correlation.
References: ASH G6PD Guidelines, 2023; Blood, Cappellini MD, 2022.
