Report 2008-2010

Until recently, IS6110-RFLP and spolygotyping were recognized as the
reference methods. Currently, IS6110-RFLP assay are replacing by 24-
locus MIRU-VNTR typing as the gold standard for genotyping of M.
tuberculosis. Therefore, in the frame of the TB PAN-NET project we
have started molecular epidemiology study of drug resistant strains in
Vilnius by using MIRU-VNTR typing as well. The results demonstrated
a good correlation between these both techniques.
Investigation of mutations conferring M. tuberculosis resistance to the
second-line drugs was continued by search for mutations associated
with resistance to ofloxacin and reserve aminoglycosides. Currently,
our collections consist of 126 ofloxacin-resistant isolates and 152
kanamycin-resistant, including 26% amikacin-resistant isolates, from
different patients and characterized in detail by the means of genotyping.
However, only 82% of ofloxacin- resistant isolates carried resistance
conferring mutations in the quinolone resistance-determining
regions (QRDR) of gyrA or gyrB genes and 16% of kanamycin-resistant
strains had mutations in the rrs gene. These results demonstrated
that significant part of resistant cases cannot be explained by the presence
of mutations in the well-recognized hot spot regions of M. tuberculosis
chromosome (Devaux et al., Euro Surveill. 2010). Search for
novel mutations associated with M. tuberculosis resistance to these
drugs is in progress.
This work was supported by the Lithuanian State Science and Studies
Foundation (grant No. C-01), EC FP7 Health Programme (Project TB
PAN-NET, grant No. 223681), and Agency for Science, Innovation and
Technology (grants No. 31V-169, No. 31V-32).
Dr. P.Stakėnas and junior scientist D.Bakonytė
perform genotyping of M.tuberculosis
Collaboration
Dr. R.Ulrich, Friedrich-Loeffler Institute, Greifswald-Insel Riems, Germany
Dr. V.Gorboulev, Wurzburg University, Wurzburg, Germany
Dr. W.Michalski, Australian Animal Health Laboratory, Australia
Prof. L.Poellinger, Karolinska Institute, Stockholm, Sweden
Dr. J.Makino, Tokyo University, Tokyo, Japan
Prof. E. Pettersen, Oslo University, Oslo, Norway
Prof. P.Ebbesen, Aalborg University, Aalborg, Denmark
Prof.A.C. Cato, Karlsruhe University, Karlsruhe, Germany
Dr. E. Davidavičienė, Dr. E. Pimkina, National Tuberculosis and Infectious Diseases University Hospital, Vilnius, Lithuania.
Prof. A. Pavilonis, Kaunas University of Medicine, Lithuania.
Dr. D. M. Cirillo, San Raffaele Scientific Institute, Milan, Italy.
Prof. F. Drobniewsky, Queen Mary and Westfield College, University of London, United Kingdom
Prof. A. Gori, San Gerardo Hospital, Italy
Dr. D. van Soolingen, National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.
Grants
EU Framework 6th Programme
EU Framework 7th Programme
Lithuanian State Science and Studies Foundation/Lithuanian Science Council
Lithuanian Agency for Science, Innovation and Technology
Contracts
UAB Fermentas, Vilnius, Lithuania
Abcam Ltd, Cambridge, UK
Santa Cruz Biotechnology, USA
35 th anniversary
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