Method

Sputum samples were thinned with sodium hydroxide for 10 min then treated with different concentrations of disinfectants for 20 min. After this time, phosphate buffer was added and the samples centrifuged at 4,000 x g for 20 min. The pellets were resuspended in 1 ml phosphate buffer and used to inoculate solid LJ and liquid MGIT culture tubes.

 

Results

There was 100% agreement between the solid LJ and MGIT liquid culture results. The results are shown in the table below with the disinfectant and concentration used.

Discussion

At the concentrations tested, ultraseptin appeared to be more effective than klenophen for inactivation of TB in thinned sputum. In this study, the sputum was thinned with sodium hydroxide prior to treatment in order to ensure that the disinfectant could get access to the bacilli. It is not known whether the presence of sodium hydroxide could have affected the disinfection making it more or less effective. This disinfection study is part of our efforts to ensure that when culture of the extracted mycobacteria is not required that our TB-Bead technology can be used in the safest working environment. We have previously shown that these disinfectants do not interfere with our TB-Bead protocol.


NOTE: the numbers of sputum samples tested were small and it should not be assumed that either disinfectant will inactivate all of the TB in every sample. In order to demonstrate this, a larger study should be performed. WORK SAFELY!

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Aim

To evaluate disinfectants (that are compatible with our TB-Bead technology) for the inactivation of TB in thinned sputum.

At the concentrations tested, ultraseptin is more effective than klenophen (see table below).


Microsens Medtech

Investigation of klenophen and ultraseptin for inactivation of TB in sputum


TB-Beads can be used to extract TB from sputum in a rapid, simple and highly efficient manner without centrifugation (please click here to visit our web site to see back issues of our Newsletter). The extracted mycobacteria can be used for microscopy, culture and molecular assays. In this issue of our Newsletter we look at a study that investigates disinfectants that are compatible with our TB-Bead technology for the inactivation of Mycobacterium tuberculosis in sputum so that extractions can be performed more safely when culture is not required.

Consumption  June 2011/1

+, growth of TB; -, no growth of TB