Background: Tuberculosis (TB) diagnosis by culture in most
resource-limited settings is hampered by high contamination rate
varying up to 31%. Reduction of oral microorganism loads by mouth rinse
with antiseptic before sputum collection showed a reduction of
contamination. Moreover, knowing the characteristic of residual
contaminant microorganisms would be an asset to understand
contamination issues. Objectives: The aim of this study was to evaluate
the effects of mouth rinsing with chlorhexidine on mycobacteria culture
contaminations and to characterize morphologically the residual
contaminants. Methods: We consecutively included 158 patients in a TB
center. Each of them supplied two sputa: The first before mouth rinse,
and the second after 60sec of mouth rinsing with chlorhexidine (0.1%).
Petroff method and Lowenstein-Jensen media were used for sputum
decontamination and inoculation respectively. The contamination rates
were compared, and the type of residual contaminants were characterized
and compared. Results: The contamination rate did not differ before and
after the mouth rinse (respectively 58/150 (39 %) vs 61/150 (41 %),
p=0.7). The major residual contaminants were Gram positive spore
forming bacteria (94%). Conclusion: Chlorhexidine mouth rinsing before
sputum collection did not reduce mycobacterial culture contamination
rate. This is probably due to spore forming bacteria, highlighted as
major residual contaminants. DOI:
https://dx.doi.org/10.4314/ahs.v19i1.3 Cite as: Kabore A,
Tranchot-Diallo J, Sanou A, Hien H, Daneau G, Gomgnimbou MK, Meda N,
Sangar\ue9 L. Why Oral antiseptic mouth rinsing before sputum
collection cannot reduce contamination rate of mycobacterial culture in
Burkina-Faso. Afri Health Sci. 2019;19(1): 1321-1328.
https://dx.doi.org/10.4314/ahs.v19i1.