Background: A rapid accurate identification of
Mycobacterium bovis is essential for surveillance purposes.
Objectives: A PCR
pncA-Restriction Fragment Length Polymorphism (RFLP) and a multiplex PCR based on the detection
of 3 regions of difference (RD-PCR): RD9, RD4 and RD1 were evaluated for the identification of
M. bovis in lymph nodes
cultures, in Tunisia, during 2013-2015.
Methods: Eighty-two
M. tuberculosis
complex strains were identified using the biochemical tests, GenoType MTBC assay,
PCR pncA-RFLP and RD-PCR.
Results: The PCR
pncA-RFLP showed that 54
M. bovis strains, identified by GenoType MTBC, had a mutation at position
169 of
pncAi> gene. Twenty-eight strains did not show any mutation at this position 27
M. tuberculosis isolates and one
M. caprae
. The PCR
pncA-RFLP had a sensitivity of 100.0% (95%CI: 93.3 -100.0) and a specificity of 100.0% (95%CI: 87.9-100.0) for identifying
M. bovis. The RD-PCR showed that all
M. bovis strains had the RD9 and RD4 deleted but presented
RD1. RD-PCR also presented high sensitivity and specificity in detecting
M. bovis strains (100.0%).
Conclusions: PCR
pncA-RFLP and RD-PCR represent very accurate and rapid tools to identify
M. bovis. They can be easily
implemented in each laboratory due to their low cost and easy use.
