Epidemiology and patterns of drug resistance among tuberculosis patients in Northwestern Iran.

BACKGROUND: Multidrug-resistant tuberculosis (MDR-TB) has emerged as an important global health concern and is on the rise throughout the world. OBJECTIVE: The aim of this study was to examine the epidemiology and pattern of TB drug resistance. METHODS: In this cross-sectional study, 180 pulmonary TB patients from two Northwestern provinces of Iran were selected. The first and second line drug susceptibility testing was carried out using the 1% proportion method on the Lφwenstein-Jensen medium. Full demographic, environmental and clinical history was evaluated. RESULTS: Prevalence of resistance to any TB drug was 13.8%. Eight (4.4%) patients had MDR-TB (2.4% in the province of East Azerbaijan and 9.3% in the province of Ardabil) and one patient had extensively drug-resistant TB. Patient resistance to both isoniazid and streptomycin was the most prevalent at a rate of 8.3%. Patients showed the least resistance to ethambutol (2.8%). There was a significant relationship between the previous history of TB drug treatment and TB drug resistance. Migrants from rural to urban areas were in high-risk groups for the occurrence of TB drug resistance. CONCLUSION: In our study, prevalence of MDR was less than the global average. It is essential to monitor the patients with previous history of TB treatment and migrants by rapid and accurate techniques in terms of drug-resistance odds.

Molecular Epidemiology of Mycobacterium Tuberculosis Strains in the North-West and West of Iran.

BACKGROUND: Identifying Mycobacterium tuberculosis (MTB) transmission type is a key step in the control of this disease. AIM: This study aimed to determine the path and transmission type of MTB and the insertion sequence IS6110 band number and verify their relationship to demographic and clinical risk factors. SUBJECTS AND METHODS: In this cross-sectional study, 64 MTB patients from three border provinces of Iran were selected after full clinical history and physical evaluation design. The drug susceptibility testing was carried out using the standard proportion technique on sputum samples. Isolates tested with restriction fragment length polymorphism technique used IS6110. RESULTS: Recent transmission of disease was 33/50 (66%) based on clustering rate. The IS6110 band number had a significant relationship with drug resistance detected in proportion method tested by univariate linear regression (P < 0.01). Furthermore, the IS6110 band number had association with Bacillus Calmette-Guérin vaccination history (P = 0.02), sex (P < 0.01), and purified protein derivative (PPD) reaction size (P < 0.01) tested by multiple analysis. The risk of recent transmission inferred from the clustering rate was significantly higher in patients from Western provinces compared to those from the North-West province (P = 0.048). However, age (P = 0.39), gender (P = 0.16), vaccination history (P = 0.57), drug susceptibility, and PPD (P < 0.6) were independent of clustering. The largest cluster of up to six subjects was found in the Western provinces. CONCLUSION: Recent MTB transmission was much more common in the West compared to the North-West of Iran. Large MTB clusters with strong epidemiological links may be reflective of a disease outbreak. Correlation noted between the IS6110 band number and vaccination history; PPD size and female gender necessitates further studies.

IL-10 G-1082A gene polymorphism and susceptibility to upper respiratory tract infection among endurance athletes.

AIM: The aim of this study was to investigate the influence of IL-10 gene polymorphisms on URTI incidence. METHODS: To this end, one hundred healthy elite male athletes participating in the study were classified as either healthy or prone to frequent URTI. Blood samples and DNA isolation, multiplex PCR, and Taqman real-time PCR were carried out. Genomic DNA was extracted from peripheral leukocytes of whole blood samples using the QIAmp DNA Blood Mini Kit (Qiagen, Hilden, Germany). For comparison of the distribution of genotypes between two groups and for estimating odds ratios (OR) for URTI susceptibility in relation to the IL-10 polymorphism, Pearson's chi-square and Logistic regression method were used respectively. RESULTS: The IL-10-1082 genotype distribution differed between athletes with URTI and healthy athletes (χ2=8. 14, P=0.017). The IL-10 high-expression genotype (GG), relative to the other two genotypes combined (AG + AA), was associated with a tendency for an increased likelihood of frequent URTI (OR: 4. 63, 95% CI: 1. 58-21. 53; P=0. 033). CONCLUSION: In conclusion, findings from this study have identified a potential role of genetic variation in influencing the risk for URTI in athletic populations and SNPs in the IL-10 genes were associated with an altered risk profile. These measures may have a predictive value in the identification of individuals who are more likely to experience recurrent infections when exposed to high physical stress in the areas of athletic endeavor.