Published on LMS

This hardware problem occurs when a cartridge is stuck inside a CBNAAT module.

Causes

• Module mechanical malfunction during the test
• Electrical failure

Solutions for releasing a stuck cartridge

Solution 1: Verify that the module door is not open. Gently try to open the module door.

Solution 2: Try to remove the cartridge from the software.

Common hardware problems that can occur while using the CBNAAT machine and their recommended solutions are listed below.

The CBNAAT software displays the result as Rif Indeterminate when the early Cycle threshold (Ct) value is greater than 35, which suggests that the bacillary load in the specimen is very low.  

The software cannot calculate the difference in the Ct values, hence the result is declared 'Indeterminate'. ​ 

This can be seen in the figure below.

Figure: Ct>35 shows Rif Indeterminate Result

Resources

In Cartridge-based Nucleic Acid Amplification Test (CBNAAT) assay, the basis for detection of rifampicin resistance is the difference between the first or early Cycle threshold (Ct) and the last or late Ct value, of M. tuberculosis-specific probes. Or the difference between probes with the maximum Ct value and minimum Ct value is greater than four.

The Cartridge-based Nucleic Acid Amplification Test (CBNAAT) software generates the results from the measured fluorescence signals and embedded calculation algorithms. In addition to qualitative results, the software provides semi-quantitative results, which provide information about the bacterial load in the specimens tested.

Semi-quantitative result interpretation is based on Cycle threshold (Ct) values of Mycobacterium tuberculosis(MTB) specific targets (Figure 1).

The comparison of the Acid-Fast Bacilli (AFB) and Light Emission Diode (LED) Fluorescence Microscopy is tabulated below:

The different meetings conducted at the Tuberculosis Units (TU) are:

Introduction

Performance Indicator - Percentage of People Living with HIV (PLHIV) given INH Preventive Treatment (IPT) Against Total Eligible PLHIV

Measures the capacity of the programme to initiate TB preventive treatment for all individuals with HIV who are eligible for the same.

NTEP Performance Indicator - Percentage of Children given Chemoprophylaxis from the Total Eligible Children Identified

This indicator measures the capacity of the programme to initiate TB Preventive Treatment  (TPT) in children < 5 years of age eligible for the same.