OBJECTIVES: Extensively drug-resistant tuberculosis (XDR-TB) is more expensive and difficult to treat than multidrug-resistant tuberculosis (MDR-TB), and outcomes for patients are much worse; therefore, it is important that clinicians understand the magnitude and distribution of XDR-TB. We conducted a retrospective study to compare the estimated incidence of and risk factors for M/XDR-TB with those of susceptible TB controls. METHODS: Sputum culture and drug susceptibility testing (DST) were performed in patients with known or suspected TB. Strains that were identified as MDR were subjected to DST for second-line drugs using the proportion method. RESULTS: Among 1,442 TB patients (mean age, 46.48 ± 21.24 years) who were culture-positive for Mycobacterium tuberculosis, 1,126 (78.1%) yielded isolates that were resistant to at least one first-line drug; there were 33 isolates (2.3%) of MDR-TB, of which three (0.2%) were classified as XDR-TB. Ofloxacin resistance was found in 10 (0.7%) isolates. Women were 15% more likely than men to yield M/XDR-TB isolates, but this difference was not significant. In a multivariate analysis comparing susceptible TB with X/MDR-TB, only one variable—the number of previous treatment regimens—was associated with MDR (odds ratio, 1.06; 95% confidence interval, 1.14–21.2). CONCLUSION: The burden of M/XDR-TB cases is not sizeable in Iran. Nonetheless, strategies must be implemented to identify and cure patients with pre-XDR-TB before they develop XDR-TB. Our results provide a greater understanding of the evolution and spread of M/XDR-TB in an environment where drug-resistant TB has a low incidence.
Extensively Drug-Resistant Tuberculosis* ; Female ; Humans ; Incidence ; Iran* ; Male ; Methods ; Multivariate Analysis ; Mycobacterium tuberculosis ; Ofloxacin ; Retrospective Studies ; Risk Factors* ; Sputum ; Tuberculosis* ; Tuberculosis, Multidrug-Resistant

Objectives: This study aimed to evaluate the specificity, sensitivity, cost, and turn-around time of three methods of gene polymorphism analysis and to study the relationship between IL28B rs12979860 and SVR rate to pegIFN-α/RVB therapy among patients with chronic hepatitis C. Methods: A total of 100 samples from chronic hepatitis C patients were analyzed in parallel using the three methods: direct sequencing, real-time polymerase chain reaction (PCR), amplification refractory mutation system (ARMS)-PCR. Results: The different profiles for IL28B rs12979860 alleles (CC, CT, and TT) obtained with PCR-RFLP, ARMS-PCR, and direct sequencing were consistent among the three methods. Prevalence of rs12979860 genotypes CC, CT and TT in HCV genotype 1a was 10(19.6%), 35(68.6%), and six (11.8%), respectively, and in HCV genotype 31, it was 13(26.5%), 31(63.3%), and five (10.2%), respectively. No significant difference was seen between rs12979860 genotype and HCV genotype (p = 0.710). Conclusion Screening by ARMS – PCR SNOP detection represents the most efficient and reliable method to determine HCV polymorphisms in routine clinical practice.