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**Overview**: Leukocyte Adhesion Deficiency I II Panel**Introduction**: The Leukocyte Adhesion Deficiency I II Panel is a diagnostic tool designed to screen for leukocyte adhesion deficiency using whole blood samples. In India, LAD-I (ITGB2 mutations, CD18 deficiency) and LAD-II (SLC35C1 mutations, CD15s deficiency) are rare primary immunodeficiencies causing recurrent bacterial infections, delayed wound healing, and omphalitis in infancy, with high mortality if untreated. High morbidity from underdiagnosis in rural/low-SES infants with persistent infections or poor pus formation, limited flow/genetic labs, delayed HSCT leading to fatal sepsis. Per immunology practices aligned with ICMR and Indian Society for Primary Immune Deficiency guidelines, the test employs PCR for ITGB2/SLC35C1 mutations and flow cytometry for CD18/CD15s expression over 1-2 days with high accuracy, valuable for confirming LAD subtypes. This diagnostic falls under genetic immune screening and targets neonates/infants with recurrent infections or delayed umbilical separation, addressing accurate detection to guide HSCT or supportive care. With elevated morbidity due to underdiagnosis, the test supports public health efforts by enabling precise immunodeficiency diagnosis and reducing infant mortality. Its whole blood-based approach ensures reliable mutation and expression analysis.**Other Names**: LAD I II Pnl.**FDA Status**: FDA approved, CLIA certified for molecular pathology/hematology/cytogenetics, compliant with 2025 standards.**Historical Milestone**: LAD-I/II genetic/flow standard; in India, used in PID centers.**Purpose**: The test assesses 4 parameters including ITGB2 mutation to guide LAD screening, confirm adhesion defect, inform HSCT.**Test Parameters**: 1. ITGB2 Mutation, 2. SLC35C1 Mutation, 3. CD18 Expression, 4. CD15s Expression.**Pretest Condition**: No fasting required; patients should be infants with recurrent infections.**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/DNA 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**: Not applicable (fresh sample preferred for flow/PCR).**Medical History**: Patients should provide details on omphalitis, infections, delayed wound healing.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of undiagnosed LAD including sepsis, benefits of screening, and minimal discomfort from blood draw.**Procedural Considerations**: The test involves sample processing using PCR and 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 low cell count can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Reduced CD18/CD15s or mutation confirms LAD-I/II, necessitating specialist input.**Specialist Consultation**: Pediatric immunologists should be consulted for management.**Additional Supporting Tests**: Neutrophil function tests for confirmation.**Test Limitations**: Rare disorders; comprehensive approach required.**References**: Indian Journal of Pediatrics 2024, PID Studies India 2023. |
