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**Overview**: Allergic Bronchopulmonary Aspergillosis Panel**Introduction**: The Allergic Bronchopulmonary Aspergillosis Panel is a diagnostic tool designed to diagnose allergic bronchopulmonary aspergillosis using serum samples. In India, ABPA is a significant hypersensitivity complication in asthma patients, with prevalence estimated at ~5% in general asthmatics but higher in severe cases (up to 63.2% in North West India tertiary studies, 11.3% overall in some cohorts, and Aspergillus sensitization ~25%). Studies from North India and multicenter data show ABPA in 11-21% of asthmatics, with pooled rates higher than global averages due to humid climate, monsoons favoring Aspergillus fumigatus, and high asthma burden (~37.5 million cases). ABPA presents with wheezing, productive cough, hemoptysis, bronchiectasis, and frequent exacerbations, often overlapping with tuberculosis (common differential in India), leading to delayed diagnosis in rural/low-SES areas with limited pulmonology access. High morbidity from underdiagnosis, progression to fibrotic lung disease, hospitalizations, and mortality if untreated. Per ICMR/Indian Chest Society guidelines and ISHAM criteria, the test employs immunoassay for detailed parameter analysis over 1-2 days with high sensitivity/specificity, valuable for early detection in poorly controlled asthmatics (e.g., central bronchiectasis, elevated total IgE >1000 IU/mL). This immunology diagnostic targets suspected ABPA in asthma clinics nationwide, addressing accurate Aspergillus-specific IgE/IgG detection to guide corticosteroid/antifungal therapy and prevent irreversible damage. With elevated morbidity from underdiagnosis in community settings, the test supports public health efforts by enabling precise identification, facilitating management, reducing exacerbations, and improving quality of life amid rising fungal exposure. Its serum-based approach ensures reliable performance even in resource-limited labs across states.**Other Names**: ABPA Pnl.**FDA Status**: FDA approved, CLIA certified for immunology, compliant with 2025 standards; aligns with ICMR diagnostics.**Historical Milestone**: Recognized in 1950s; in India, prominence post-2010s studies highlighting high prevalence in asthma cohorts.**Purpose**: The test screens for 3 parameters including total IgE to guide ABPA diagnosis, assess Aspergillus sensitization, determine hypersensitivity stage, and inform treatment/prevention strategies in high-prevalence asthma settings.**Test Parameters**: 1. Total IgE, 2. Aspergillus-specific IgE, 3. Aspergillus-specific IgG.**Pretest Condition**: No fasting required; patients should report wheezing, productive cough, hemoptysis, recurrent asthma exacerbations, or environmental Aspergillus exposure.**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 asthma control, exacerbations, productive cough, hemoptysis, prior fungal exposure, tuberculosis history, or family allergy/atopy.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of untreated ABPA including bronchiectasis/respiratory failure, benefits of early detection, 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, and store kits according to manufacturer specifications to ensure reliability.**Factors Affecting Result Accuracy**: Delays beyond stability periods, improper storage conditions, hemolysis, concurrent infections (e.g., TB), or corticosteroid use can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Abnormal results indicate possible ABPA, necessitating further investigation like specialist consultation or additional testing. Normal results may require follow-up if symptoms persist.**Specialist Consultation**: Pulmonologists or allergists should be consulted for case management, treatment planning, and coordination with health programs.**Additional Supporting Tests**: HRCT chest, sputum for Aspergillus, spirometry for confirmation.**Test Limitations**: The test may produce false negatives in early stages or false positives in cross-reactivity; requiring a comprehensive diagnostic approach that includes clinical correlation.**References**: Agarwal et al. Clin Exp Allergy 2023, Indian Journal Chest Diseases 2024, ICMR Guidelines 2025. |
