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**Overview**: Human Leukocyte Antigen Mixed Antibody PRA Panel**Introduction**: The Human Leukocyte Antigen Mixed Antibody PRA Panel is a diagnostic tool designed to screen for mixed HLA antibodies using serum samples. In India, mixed PRA (Class I + Class II + MICA) detects broad sensitization in transplant candidates, critical for avoiding incompatible donors in kidney/heart transplantation. High morbidity from under-screening in rural/low-SES patients on waiting lists, limited labs, delayed virtual crossmatch leading to prolonged dialysis or graft loss. Per immunology practices aligned with ICMR and Indian Society of Organ Transplantation guidelines, the test employs immunoassay for PRA Class I, Class II, and MICA antibodies over 1-2 days with high accuracy, valuable for pre-transplant sensitization profiling. This diagnostic falls under transplant screening and targets sensitized candidates (prior transplant, multiparous women), addressing accurate detection to guide donor selection or desensitization protocols. With elevated morbidity due to under-testing, the test supports public health efforts by enabling precise antibody assessment and improving transplant success rates. Its serum-based approach ensures reliable mixed antibody screening.**Other Names**: HLA Mixed PRA Pnl.**FDA Status**: FDA approved, CLIA certified for immunology, compliant with 2025 standards.**Historical Milestone**: Mixed PRA standard; in India, used in transplant registries.**Purpose**: The test assesses 3 parameters including PRA Class I to guide mixed antibody screening, detect broad sensitization, inform donor matching.**Test Parameters**: 1. PRA Class I, 2. PRA Class II, 3. MICA Antibodies.**Pretest Condition**: No fasting required; patients should be transplant candidates.**Specimen**: 3 mL serum in 1 SST, transported within specified times to maintain sample viability.**Sample Stability at Room Temperature**: 8 hours with proper handling to preserve analyte integrity, 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**: 6 months at -20 degrees Celsius, allowing long-term storage for retesting, though freezing may affect some analytes.**Medical History**: Patients should provide details on prior transplants, transfusions, pregnancies.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of undetected sensitization including rejection, benefits of screening, and minimal discomfort from venipuncture.**Procedural Considerations**: The test involves sample processing using immunoassay 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, hemolysis, or recent transfusion can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: High mixed PRA indicates broad sensitization, necessitating specialist input.**Specialist Consultation**: Transplant immunologists should be consulted for management.**Additional Supporting Tests**: Single antigen bead for specificity.**Test Limitations**: Broad screen; comprehensive approach required.**References**: Indian Journal of Transplantation 2024, Transplant Studies India 2023. |
