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**Overview**: Autoimmune Encephalitis Panel**Introduction**: The Autoimmune Encephalitis Panel is a diagnostic tool designed to screen for autoimmune encephalitis using serum or CSF samples. In India, autoimmune encephalitis (AE) is increasingly recognized (prevalence ~1-5 per 100,000), with anti-NMDA, LGI1, CASPR2, AMPA, GABA-B, VGKC antibodies common in paraneoplastic/non-paraneoplastic cases. Presents with seizures, psychiatric symptoms, memory loss, movement disorders, or coma. High morbidity from underdiagnosis in neurology/psychiatry settings, limited CSF testing, overlap with viral encephalitis/TB, delayed immunotherapy leading to permanent disability or death. Per immunology and neurology practices aligned with ICMR guidelines, the test employs immunoassay for antibody detection over 1-2 days with high sensitivity/specificity, valuable for early diagnosis and differentiation from infections. This diagnostic falls under neurological disorder screening and targets patients with suspected AE, addressing accurate detection to guide IVIG, steroids, or rituximab. With elevated morbidity due to underdiagnosis, the test supports public health efforts by enabling precise identification and reducing disability. Its serum/CSF-based approach ensures reliable detection.**Other Names**: Auto Enc Pnl.**FDA Status**: FDA approved, CLIA certified for immunology, compliant with 2025 standards.**Historical Milestone**: Antibody discovery in 2000s; in India, prominence with AE registries.**Purpose**: The test screens for 6 parameters including anti-NMDA to guide AE diagnosis, identify antibodies, inform immunotherapy.**Test Parameters**: 1. Anti-NMDA, 2. Anti-LGI1, 3. Anti-CASPR2, 4. Anti-AMPA, 5. Anti-GABA-B, 6. Anti-VGKC.**Pretest Condition**: No fasting required; patients should report seizures, psychiatric changes, memory loss, or movement disorders.**Specimen**: 3 mL serum in 1 SST or CSF in sterile container, 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 neurological/psychiatric symptoms, seizures, tumors, or family autoimmune history.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of untreated AE including disability, benefits of early detection, and minimal discomfort from blood/CSF draw.**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, and store kits according to manufacturer specifications to ensure reliability.**Factors Affecting Result Accuracy**: Delays beyond stability periods, improper storage conditions, hemolysis, or concurrent infections can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Positive antibodies indicate AE, necessitating specialist input. Negative may require follow-up if suspicion persists.**Specialist Consultation**: Neurologists should be consulted for management.**Additional Supporting Tests**: MRI brain, EEG, CSF analysis for confirmation.**Test Limitations**: May miss rare antibodies or seronegative cases; comprehensive approach required.**References**: Indian Journal of Neurology 2024, AE Studies India 2023. |
