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**Overview**: Chromosomal Microarray Postnatal Panel**Introduction**: The Chromosomal Microarray Postnatal Panel is a diagnostic tool designed to screen for postnatal genetic disorders using whole blood samples. In India, postnatal CMA is recommended for unexplained developmental delay, intellectual disability, autism spectrum disorders, and congenital anomalies (yield 15-20 percent higher than karyotype). High burden from underdiagnosis in rural/low-SES children, limited pediatric genetics access, delayed diagnosis leading to missed early interventions. Per cytogenetics practices aligned with ICMR and Indian Academy of Pediatrics guidelines, the test employs microarray for CNV detection over 1-2 days with high resolution/sensitivity, valuable for postnatal evaluation. This diagnostic falls under postnatal genetic screening and targets children with developmental concerns, addressing accurate detection to guide therapy and counseling. With elevated morbidity due to underdiagnosis, the test supports public health efforts by enabling precise identification and improving outcomes. Its whole blood-based approach ensures reliable detection.**Other Names**: Microarray Post Pnl.**FDA Status**: FDA approved, CLIA certified for cytogenetics, compliant with 2025 standards.**Historical Milestone**: ACMG recommendation for CMA first-tier; in India, expanding in pediatric clinics.**Purpose**: The test performs 1 parameter (postnatal microarray analysis) to guide detection of genetic disorders, identify CNVs, inform management.**Test Parameters**: 1. Postnatal Microarray Analysis.**Pretest Condition**: No fasting required; patients should report developmental delay, autism, or dysmorphism.**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 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**: Not applicable (fresh sample preferred for microarray).**Medical History**: Patients should provide details on milestones, behavior, dysmorphic features, family history.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of undiagnosed disorders including recurrence, benefits of detection, and minimal discomfort from blood draw.**Procedural Considerations**: The test involves sample processing using microarray by trained personnel to ensure sterile technique, avoid contamination, and interpret results within 1-2 days using provided controls. Laboratories must maintain a controlled environment, adhere to quality assurance protocols, and store kits according to manufacturer specifications to ensure reliability.**Factors Affecting Result Accuracy**: Delays beyond stability periods, improper storage conditions, or low DNA yield can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Abnormal CNVs indicate genetic disorder, necessitating specialist input. Normal may require follow-up if symptoms suggestive.**Specialist Consultation**: Pediatric geneticists should be consulted for management.**Additional Supporting Tests**: Exome sequencing for confirmation.**Test Limitations**: Does not detect balanced translocations; comprehensive approach required.**References**: Indian Journal of Pediatrics 2024, CMA Studies India 2023. |
