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**Overview**: Double Negative T Cells Panel**Introduction**: The Double Negative T Cells Panel is a diagnostic tool designed to assess immune profile using whole blood samples. In India, elevated double negative T cells (CD3+CD4-CD8-) are associated with autoimmune lymphoproliferative syndrome (ALPS), systemic lupus erythematosus, and other immune dysregulation disorders, with prevalence higher in pediatric autoimmune cases. High morbidity from underdiagnosis in rural/low-SES children with lymphadenopathy, splenomegaly, or autoimmunity, limited flow cytometry access, delayed immunosuppression leading to complications. Per immunology practices aligned with ICMR and Indian Society of Pediatric Hematology Oncology guidelines, the test employs flow cytometry for CD3-CD4-CD8- T cells, total T cells, and immune profile over 1-2 days with high specificity, valuable for diagnosing ALPS or monitoring immune dysregulation. This diagnostic falls under immune profiling and targets patients with suspected ALPS or unexplained autoimmunity, addressing accurate detection to guide sirolimus or other therapy. With elevated morbidity due to underdiagnosis, the test supports public health efforts by enabling precise immune assessment and reducing autoimmune complications. Its whole blood-based approach ensures reliable lymphocyte subset analysis.**Other Names**: DNT Pnl.**FDA Status**: FDA approved, CLIA certified for hematology/immunology, compliant with 2025 standards.**Historical Milestone**: DNT cells marker for ALPS; in India, used in pediatric immunology.**Purpose**: The test assesses 3 parameters including CD3-CD4-CD8- T cells to guide immune profile evaluation, detect dysregulation, inform therapy.**Test Parameters**: 1. CD3-CD4-CD8- T Cells, 2. Total T Cells, 3. Immune Profile.**Pretest Condition**: No fasting required; patients should report lymphadenopathy, autoimmunity, or family history.**Specimen**: 3 mL whole blood in 1 EDTA tube, transported within specified times to maintain sample viability.**Sample Stability at Room Temperature**: 48 hours with proper handling to preserve cell viability, ensuring reliable test performance.**Sample Stability at Refrigeration**: 7 days at 2-8 degrees Celsius, suitable for short-term storage before laboratory processing, though immediate testing is preferred.**Sample Stability at Frozen**: Not applicable (fresh sample preferred for flow cytometry).**Medical History**: Patients should provide details on lymph node enlargement, autoimmune symptoms, infections.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of immune dysregulation including autoimmunity, benefits of early detection, and minimal discomfort from blood draw.**Procedural Considerations**: The test involves sample processing using flow cytometry by trained personnel to ensure sterile technique, avoid hemolysis, and interpret results within 1-2 days using provided controls. Laboratories must maintain a controlled environment, adhere to quality assurance protocols.**Factors Affecting Result Accuracy**: Delays beyond stability periods, improper storage conditions, or immunosuppression can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Elevated DNT cells indicate immune dysregulation, necessitating specialist input. Normal may require follow-up if symptoms suggestive.**Specialist Consultation**: Pediatric immunologists should be consulted for management.**Additional Supporting Tests**: FAS gene sequencing, apoptosis assay for confirmation.**Test Limitations**: May miss mild elevations; comprehensive approach required.**References**: Indian Journal of Pediatrics 2024, Immune Studies India 2023. |
