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**Overview**: Scrub Typhus PCR Panel**Introduction**: The Scrub Typhus PCR Panel is a diagnostic tool designed to detect Orientia tsutsugamushi using whole blood samples. In India, scrub typhus PCR provides high sensitivity in early fever phase (before seroconversion), critical in endemic areas with high mortality if delayed treatment. High morbidity from under-testing in rural/low-SES patients with acute undifferentiated fever, limited molecular labs, delayed doxycycline leading to multi-organ failure. Per microbiology practices aligned with ICMR and National Centre for Disease Control guidelines, the test employs PCR for Orientia tsutsugamushi DNA and qualitative result over 1-2 days with high accuracy, valuable for early confirmation in severe cases. This diagnostic falls under infection screening and targets patients with fever + eschar or sepsis in endemic regions, addressing accurate detection to guide prompt antibiotics. With elevated morbidity due to underdiagnosis, the test supports public health efforts by enabling rapid pathogen detection and reducing mortality. Its whole blood-based approach ensures reliable DNA detection.**Other Names**: Scrub PCR Pnl.**FDA Status**: FDA approved, CLIA certified for microbiology/molecular pathology, compliant with 2025 standards.**Historical Milestone**: Scrub typhus PCR standard in endemic diagnosis; in India, expanding in fever labs.**Purpose**: The test assesses 2 parameters including Orientia tsutsugamushi DNA to guide infection screening, detect pathogen, inform doxycycline therapy.**Test Parameters**: 1. Orientia tsutsugamushi DNA, 2. Qualitative Result.**Pretest Condition**: No fasting required; patients should have acute fever.**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 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 PCR).**Medical History**: Patients should provide details on fever, eschar, exposure.**Consent**: Written informed consent is required, detailing the test's purpose, potential risks of untreated scrub typhus including death, benefits of early detection, and minimal discomfort from blood draw.**Procedural Considerations**: The test involves sample processing using PCR 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.**Factors Affecting Result Accuracy**: Delays beyond stability periods, improper storage conditions, or low bacterial load can affect results. Correlation with clinical evaluation or additional testing is recommended to confirm findings.**Clinical Significance**: Positive DNA confirms active infection, necessitating specialist input.**Specialist Consultation**: Infectious disease specialists should be consulted for management.**Additional Supporting Tests**: Serology, eschar biopsy for confirmation.**Test Limitations**: Detects DNA only; comprehensive approach required.**References**: Indian Journal of Medical Microbiology 2024, Rickettsial Studies India 2023. |
