TY - JOUR
T1 - Widespread pyrazinamide-resistant Mycobacterium tuberculosis family in a low-incidence setting
AU - Nguyen, Dao
AU - Brassard, Paul
AU - Westley, Jennifer
AU - Thibert, Louise
AU - Proulx, Melanie
AU - Henry, Kevin
AU - Schwartzman, Kevin
AU - Menzies, Dick
AU - Behr, Marcel A.
PY - 2003/7/1
Y1 - 2003/7/1
N2 - An unusually high prevalence of pyrazinamide (PZA) monoresistance in Mycobacterium tuberculosis has been observed in Quebec. In the absence of a recognized outbreak, we hypothesized that these isolates most likely represented reactivation of an old endemic strain in this low-incidence area. A case-control study of 77 PZA-resistant isolates with a specific Quebec mutation and 253 PZA-susceptible control M. tuberculosis isolates was undertaken. By molecular analysis, all 77 case isolates shared a unique mutation profile in the pncA gene which was not present in control isolates. While control isolates manifested diverse IS6110 restriction fragment length polymorphism (RFLP) patterns, spoligotypes, and major genetic groups, case isolates had similar but nonidentical IS6110 RFLP patterns, had common spoligotypes, and were confined to one major genetic group, suggesting a common clonal ancestor. By epidemiologic and geographic analyses, however, there were no significant differences between the cases and the controls. We conclude that a clonally related family of PZA-monoresistant M. tuberculosis isolates in Quebec represents historic rather than recent transmission.
AB - An unusually high prevalence of pyrazinamide (PZA) monoresistance in Mycobacterium tuberculosis has been observed in Quebec. In the absence of a recognized outbreak, we hypothesized that these isolates most likely represented reactivation of an old endemic strain in this low-incidence area. A case-control study of 77 PZA-resistant isolates with a specific Quebec mutation and 253 PZA-susceptible control M. tuberculosis isolates was undertaken. By molecular analysis, all 77 case isolates shared a unique mutation profile in the pncA gene which was not present in control isolates. While control isolates manifested diverse IS6110 restriction fragment length polymorphism (RFLP) patterns, spoligotypes, and major genetic groups, case isolates had similar but nonidentical IS6110 RFLP patterns, had common spoligotypes, and were confined to one major genetic group, suggesting a common clonal ancestor. By epidemiologic and geographic analyses, however, there were no significant differences between the cases and the controls. We conclude that a clonally related family of PZA-monoresistant M. tuberculosis isolates in Quebec represents historic rather than recent transmission.
UR - http://www.scopus.com/inward/record.url?scp=0038168538&partnerID=8YFLogxK
U2 - 10.1128/JCM.41.7.2878-2883.2003
DO - 10.1128/JCM.41.7.2878-2883.2003
M3 - Article
C2 - 12843016
AN - SCOPUS:0038168538
SN - 0095-1137
VL - 41
SP - 2878
EP - 2883
JO - Journal of Clinical Microbiology
JF - Journal of Clinical Microbiology
IS - 7
ER -