European Society of Mycobacteriology - Instituto Nacional de Saúde ...

OP-11
Mycobacterium avium SUBSPECIES STRAINS
FROM HUMAN AND ANIMAL ORIGIN
Radomski, Nicolas 1 , Thibault, Virginie 2 , Karoui, Claudine 1 , De Cruz, Krystel 1 , Cochard, Thierry 1 , Gutiérrez, Cristina 3 ,
Supply, Philip 3 , Biet, Frank 2 , Boschiroli, María Laura 1
1 - AFSSA-LERPAZ, Maisons Alfort
2 - INRA-UR1282, Nouzilly
3 - INSERM U629-Institut Pasteur, Lille
The Mycobacterium avium sbsp. avium and Mycobacterium avium sbsp. hominissuis are pathogenic emergent bacterial species
belonging to the Mycobacterium avium complex (MAC). These two subspecies can infect and lead to disease to numerous
animal species: birds, pigs, cattle, deer, sheep, goats, horses, cats, dogs, etc. Moreover, Mycobacterium avium subspecies
have been isolated in HIV infected patients and in immuno-competent patients with pulmonary pathologies. MAC is
an ubiquitous bacterial group that can be found in water, in the environment, or even in food. A molecular typing study
was undertaken with the primary goal of improving the taxonomic and epidemiological knowledge of MAC. Different
strains of Mycobacterium avium sbsp. avium, Mycobacterium avium sbsp. hominissuis, and also of Mycobacterium avium sbsp.
silvaticum, isolated from animals, humans, and the environment, were typed by two methods: the Restriction Fragments
Length Polymorphism on insertion sequences IS1311 (RFLP1311), which is a standard method to characterise MAC, and
the Variable Number of Tandem Repeats-Mycobacterial Interspersed Repetitive Units (VNTR-MIRUs) characterisation,
which has been recently developed on Mycobacterium avium sbsp. paratuberculosis. Our results demonstrate that the
discrimination power of both methods is comparable (DI of more than 0.92). Therefore, VNTR-MIRUs seems a much
better typing method since it is a PCR based method that requires little genetic material for being performed, which is
easy to standardize in any laboratory and because the deduced numerical patterns do not require special softwares for
being compared in an inter-laboratories fashion.
European Society of Mycobacteriology | 30 th Annual Congress | July 2009 | Porto - Portugal
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