Overview: CD22 Flow Cytometry Test
Introduction: The CD22 Flow Cytometry Test detects CD22 markers to diagnose lymphoma or leukemia, causing swollen lymph nodes or bruising. Following 2023 ASH guidelines, it uses flow cytometry for high specificity, aiding in cancer screening. This test is critical for guiding diagnosis, treatment, and improving outcomes in hematology for patients with suspected hematologic malignancies.

Other Names: CD22 Flow Assay, B-Cell Marker Test.

FDA Status: Laboratory-developed test (LDT), meeting hematology standards for diagnostic accuracy.

Historical Milestone: CD22 testing began in the 1990s with lymphoma research. Flow cytometry emerged in the 2000s, and standardized panels enhanced accuracy by the 2010s.

Purpose: Diagnoses lymphoma or leukemia, guides treatment, and monitors CD22 markers in patients with swollen lymph nodes or bruising.

Test Parameters: 1. CD22

Pretest Condition: No fasting required. Collect whole blood or bone marrow at any time. Report symptoms like swollen lymph nodes or bruising, and list medications.

Specimen: 2-5 mL whole blood (EDTA) or 2-5 mL bone marrow (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 swollen lymph nodes, bruising, or history of lymphoma/leukemia. Include current medications, especially chemotherapeutics.

Consent: Written consent required, detailing the tests purpose, diagnostic implications, and potential need for cancer therapy.

Procedural Considerations: Uses flow cytometry to detect CD22 markers. Results are available in 1-2 days, enabling rapid clinical decisions.

Factors Affecting Result Accuracy: Poor sample quality or low cell yield can affect results. Non-malignant conditions may express CD22.

Clinical Significance: Positive CD22 expression suggests lymphoma or leukemia, prompting targeted therapy. Negative results may require additional marker testing.

Specialist Consultation: Consult a hematologist or oncologist for result interpretation.

Additional Supporting Tests: Bone marrow biopsy, other flow cytometry markers (e.g., CD19, CD20), or imaging to confirm lymphoma/leukemia.

Test Limitations: Non-specific expression may occur in non-malignant conditions. Results require clinical correlation.

References: ASH Leukemia Guidelines, 2023; Blood, Arber DA, 2022.