The MGIT 960 Growth Supplement (Figure below) is the enrichment added to the MGIT medium prior to inoculation of specimen. 

It provides substances essential to the growth of mycobacteria, such as:

The MGIT tube contains a modified Middlebrook 7H9 broth base, which contains large amounts of dissolved oxygen (Figure below). The headspace of the tube is flushed with a carbon dioxide enriched atmosphere.

Components of MGIT Medium Tube

MGIT 960 reagents include (Figure):

1. MGIT medium; each MGIT 960 tube contains 7.0 ml of modified 7H9 broth base while the manual MGIT tube contains 4.0 ml of the medium
2. MGIT growth supplement (enrichment); growth supplement for BACTEC MGIT 960
3. MGIT PANTA, antimicrobial supplement to prevent contamination

Figure: BACTEC MGIT 960 Reagents

Storage of Reagents

Monitoring of key quality indicators or performance indicators of Truenat is important to assess the functioning of the instrument, calibration/ service requirements of the instrument, competency of the technician performing the assays and inventory management. Overall quality indicators should assess:

1. Total tests done
2. Type of samples tested
3. Test failure
4. Availability of consumables
5. Turnaround time
6. Specimen rejected
7. External Quality Assurance (EQA) results
8. Instrument downtime

Need-based maintenance for Truenat instrument is done by lab personnel/ manufacturer while the manufacturer does annual maintenance.

The tasks included under annual maintenance are:

The sputum sample needs to be processed to liquefy and lyse the specimen before Truenat testing. This is because of the following reasons:

• Sputum samples contain Polymerase Chain Reaction (PCR) inhibitors but PCR amplification requires pure DNA from sputum samples.
• The sputum sample should be homogenized and pipettable before DNA extraction can begin.
• Pre-treatment also decontaminates specimen for storage/ transportation/ extraction.

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Donning and Doffing of PPE

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