1. SPIT SEQ - Tuberculosis Whole Genome Sequencing
India's First Culture-Free Whole Genome Sequencing Based Test Directly from Clinical Samples
What is SPIT SEQ?
SPIT SEQ is a revolutionary NGS-based whole genome sequencing test that rapidly and accurately identifies drug-resistant *Mycobacterium tuberculosis* directly from both pulmonary and extra-pulmonary clinical samples, transforming TB treatment by enabling precise and timely interventions.
Key Features:
Direct Sample Testing:
- Works directly from sputum and extrapulmonary samples
- No culture required - eliminates culture failure issues
- Significantly faster results (14 days vs 6-8 weeks for culture-based DST)
Comprehensive Drug Resistance Profile:
- Predicts resistance for 18+ anti-TB drugs
- Covers first-line drugs (Rifampicin, Isoniazid, Ethambutol, Pyrazinamide)
- Covers second-line drugs (Fluoroquinolones, Aminoglycosides, etc.)
- Covers newer drugs (Bedaquiline, Delamanid, Pretomanid, Linezolid, Clofazimine)
WHO Group Classification:
- Group A drugs: Levofloxacin, Moxifloxacin, Bedaquiline, Linezolid
- Group B drugs: Clofazimine, Cycloserine
- Group C drugs: Ethambutol, Delamanid, Pyrazinamide, Imipenem, Amikacin, Streptomycin, Ethionamide
Advanced Capabilities:
- Identifies XDR (Extensively Drug-Resistant) TB cases
- Identifies true MDR (Multidrug-Resistant) TB cases
- Pre-XDR TB identification
- Provides lineage information of M. tuberculosis strain
- Detects heteroresistance (mixed resistant and susceptible populations)
- Beneficial in smear/GeneXpert positive but culture-negative cases
Technical Advantages:
- Whole genome sequencing (not amplicon-based)
- Tiling probes for enrichment covering entire genome
- Updated mutation database from WHO and global literature
- More comprehensive than LPA (Line Probe Assay)
- More economical than multiple conventional DST tests
- Outperforms conventional methods in accuracy and speed
Performance:
- 100% Specificity
- 98.04% Sensitivity
- Compared to LPA for first and second-line drugs
- Validated through extensive peer-reviewed publications
TB Burden Context:
- India accounts for ~30% of global TB cases
- 27% of global MDR/RR-TB cases
- WHO-recommended technology for drug resistance testing
- Critical for TB control programs
Why Drug Resistance Testing is Essential:
- Accurate diagnosis of specific drug-resistant strains
- Guides appropriate medication use
- Improves patient outcomes
- Prevents spread of resistant strains
- Optimizes healthcare resources
- Enables timely intervention
- Reduces complications and mortality
Clinical Applications:
- Diagnosis and drug resistance testing in single test
- Pulmonary TB (from sputum)
- Extrapulmonary TB (from various sample types)
- MDR-TB diagnosis
- XDR-TB diagnosis
- Treatment monitoring
- Epidemiological studies
- Strain typing
- Disease surveillance
Sample Requirements:
- Sputum (pulmonary TB)
- CSF, pleural fluid, ascitic fluid, pus (extrapulmonary TB)
- Fresh samples preferred
- Can work with GeneXpert-positive samples
Turn Around Time: 12-14 working days
Report Includes:
- M. tuberculosis detection (present/absent)
- Drug resistance profile for all tested drugs (Sensitive/Resistant)
- Specific mutations detected
- Lineage information
- Heteroresistance information
- Treatment recommendations
Comparison with Existing Methods:
- Conventional DST: 6-8 weeks, limited drugs, culture-dependent
- GeneXpert: 2 hours but only Rifampicin resistance
- LPA: Culture-dependent, limited to 5-8 drugs
- SPIT SEQ: Culture-free, 14 days, 18+ drugs, comprehensive
Clinical Impact:
- Reduces time to appropriate treatment initiation
- Prevents inappropriate antibiotic use
- Reduces transmission of resistant strains
- Improves treatment outcomes
- Reduces healthcare costs long-term
- Enables personalized TB treatment
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