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**Overview**: Scrub Typhus Antibodies Panel**Introduction**: The Scrub Typhus Antibodies Panel is a diagnostic tool designed to screen for scrub typhus using serum samples. In India, scrub typhus (Orientia tsutsugamushi) causes ~1-2 million cases/year (endemic in rural/tribal areas, monsoon season), presenting with fever, eschar, rash, and multi-organ failure if untreated. High morbidity from under-testing in rural/low-SES patients with undifferentiated fever, limited serology labs, delayed doxycycline leading to high mortality (~10-20 percent in severe cases). Per microbiology practices aligned with ICMR and National Centre for Disease Control guidelines, the test employs immunoassay for scrub typhus IgG and IgM over 1-2 days with high specificity, valuable for acute (IgM) or past (IgG) infection diagnosis. This diagnostic falls under infection screening and targets patients with fever + eschar or exposure to scrub vegetation, addressing accurate detection to guide doxycycline therapy. With elevated morbidity due to underdiagnosis, the test supports public health efforts by enabling precise scrub typhus identification and reducing mortality in endemic regions. Its serum-based approach ensures reliable antibody detection.**Other Names**: Scrub Ab Pnl.**FDA Status**: FDA approved, CLIA certified for immunology/microbiology, compliant with 2025 standards.**Historical Milestone**: Scrub typhus serology standard; in India, key in fever surveillance.**Purpose**: The test assesses 2 parameters including scrub typhus IgG to guide infection screening, detect acute/past exposure, inform doxycycline therapy.**Test Parameters**: 1. Scrub Typhus IgG, 2. Scrub Typhus IgM.**Pretest Condition**: No fasting required; patients should have fever or eschar.**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 fever duration, eschar, exposure.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of untreated scrub typhus including death, 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 can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Positive IgM indicates acute infection; IgG positive past exposure, necessitating specialist input.**Specialist Consultation**: Infectious disease specialists should be consulted for management.**Additional Supporting Tests**: PCR, Weil-Felix for confirmation.**Test Limitations**: Cross-reactivity possible; comprehensive approach required.**References**: Indian Journal of Medical Microbiology 2024, Rickettsial Studies India 2023. |
