A Study On The Identification And The Drug Resistance Of The "beijing Family" Strain Of Clinical Isolated Mycobacterium Tuberculosis In Xinjiang

Objective:To identify the Beijing family strain and find out the distributive status of Mycobacterium tuberculosis (M. tuberculosis) in the south region of Xinjiang, and then analysis the relationship between Beijing family strain and drug-resistant phenotypes, provide scientific basis for the prevention, treatment and molecular epidemiology of tuberculosis.Methods:The M. tuberculosis strains were collected and isolated from the sputum of inpatient and registered cases of Uygur infected with MTB in Kashi, Hetian Pulmonary Hospital and Centers for Disease Control and Prevention from Jan to Jun of 2009 and partial inpatient cases of Han infected with MTB in Department of Infectious Diseases, First Affiliated Hospital, Shihezi University, School of Medicine Shihezi from Nov of 2008 to Nov of 2009. The clinical isolates were identified with RD105 deletion test, Mean while the drug susceptibility was determined by proportion method. The Percentage and drug resistance of the Beijing family strain were counted and the results were analysised byχ2 test.Results:A total of 229 clinical isolates of M. tuberculosis was collected and identified with RD105 deletion test, in which 100 strains belong to "Beijing family" strain (43.7%) and 129 strains were non-"Beijing family" strain (56.3%), the percentages of "Beijing family" strain of Uygur and Han in Xinjiang were 39.5%(79/200) and 72.4%(21/29) respectively. There is a significant difference to the distribution of "Beijing family" strain of M.tuberculosis of Uygur and Han in Xinjiang, (x2=11.154, P=0.001,<0.05). Among 50 Beijing family strains,45 strains (90%) were drug-sensitive(RFP, INH, EMB, SM), and 5 strains(10%) were drug-resistant, while among 52 non-Beijing family strains,7 strains (13.5%) were drug-sensitive, and 45 strains(86.5%) were drug-resistant. Concerning to the drug-resistance, there was no significant difference to the Beijing family as well as the non-Beijing family (x2=0.294, p=0.588>0.05).Conclusion:M.tuberculosis of "Beijing family" strain are general prevalence in Uygur in Xinjiang, while it was the predominant strain in Han. It should be investigate whether the "Beijing family" strain of Mycobacterium tuberculosis is the predominant strain or not in the region. There were no significant correlation between Beijing family strain and drug-resistant phenotypes.