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Mycobacterium simiae is an emerging nontuberculous mycobacterium (NTM) and an opportunistic pathogen which is described mainly in Asia and presents in the environment that can cause pulmonary infection. The objective of this study is to characterize M. simiae clinical isolates using mycobacterial interspersed repetitive unit variable-number tandem repeats (MIRU-VNTR) typing for the differentiation of the strains. A total of 169 clinical isolates of NTM were recovered from patients suspected of having tuberculosis (TB)-like and related infections. After isolation and identification of mycobacterial strains by conventional biochemical and PCR-based tests, M. simiae strains were confirmed using restriction fragment length polymorphism (RFLP)-based identification assay. Furthermore, drug susceptibility and MIRU-VNTR typing was performed using on the clinical isolates of M. simiae. Out of 169 NTM strains, 92 (54.4%) isolates were identified as M. simiae. Antibiotic susceptibility experiments indicated that all 92 M. simiae isolates were resistant to first line antimycobacterial agents. Moreover, 8 (8.6%) M. simiae isolates were resistant to ciprofloxacin; and 6 (6.5%) were resistant to both amikacin and kanamycin, while the remaining were susceptible to second line antimycobacterial agents. MIRU-VNTR analysis showed that the M. simiae isolates were classified in four distinct M. simiae clusters and two single types. The minimum spanning analysis revealed that the isolates were grouped in three complexes. The data suggested that MIRI-VNTR typing is useful for typing of M. simiae isolates, however, MIRU-16 locus was absolutely absent in M. simiae.

Background: Despite the clinical and epidemiological importance of Mycobacterium simiae worldwide, including in Iran, there is no clear and effective treatment regimen for M. simiae and its different subtypes. Objectives: Concerning the superiority of molecular approaches, this study aims to identify the common M. simiae subtypes submitted to the National Reference Tuberculosis (TB) Laboratory of Iran and study the presence of drug resistance by molecular detection methods. Methods: We included sputum samples with M. simiae confirmation submitted to the National Reference TB Laboratory of Iran from May 2014 to May 2016. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay was used for drug susceptibility testing (DST). Results: Among 7200 TB suspected patients, a total of 60 M. simiae cases belonging to subtype I were identified. All the included clinical isolates met the American Thoracic Society (ATS) and Infectious Diseases Society of America (IDSA) diagnostic criteria and were considered the disease’s causative pathogen. Males (58.33%), elderly (68.54%), and patients with a history of TB (51.42%) were shown to be more prone to infection with the disease. All clinical isolates of M. simiae were resistant to rifampin (RIF) and isoniazid (INH). Amikacin/kanamycin (AMK/KAN) and ciprofloxacin (CIP) susceptibility was found to be 91.66% and 88.33%, respectively. Conclusions: Subtype I was exclusively identified among M. simiae patients in Iran. Molecular detection of drug resistance suggests that amikacin/kanamycin and ciprofloxacin could be used to treat patients infected with M. simiae subtype I.

Mycobacterium tuberculosis has infected more than two billion individuals worldwide, of whom 5%-10% have clinically active disease and 90%-95% remain in the latent stage with a reservoir of viable bacteria in the macrophages for extended periods of time. The tubercle bacilli at this stage are usually called dormant, non-viable, and/or non-culturable microorganisms. The patients with latent bacilli will not have clinical pictures and are not infectious. The infections in about 2%-23% of the patients with latent status become reactivated for various reasons such as cancer, human immunodeficiency virus infection, diabetes, and/or aging. Many studies have examined the mechanisms involved in the latent state of Mycobacterium and showed that latency modified the expression of many genes. Therefore, several mechanisms will change in this bacterium. Hence, this study aimed to briefly examine the genes involved in the latent state as well as the changes that are caused by Mycobacterium tuberculosis . The study also evaluated the relationship between the functions of these genes.

Background : Daily intake of air is 30 Ib as compared with 2-Ib of food and 4½ of water. Thereby, breathing-contaminated air is as harmful as drinking or eating contaminated water or food, respectively. Recent research has highlighted the extent of outdoor air pollution in large cities and warranted high-quality studies to clarify the magnitude of the problem. Here, we evaluated the possible association between tuberculosis (TB) development and exposure to outdoor air pollution in a metropolitan city of Tehran. Methods: Extraction and analysis of relevant data. Investigation performed on TB patients (n = 1167) that were residing in Tehran for the past 10 years. The average concentration of sulfur dioxide (SO2), nitrogen dioxide, carbon monoxide (CO), and particles with an aerodynamic diameter of ≤ 2.5μm (PM2.5) and ≤ 10.0 (PM10) was measured from Tehran Air Quality Control Corporation (TAQCC). Patient and ecological informations were analyzed using geographical information system. Results: Based on TAQCC, Tehran had an average of 180–250 polluted days per year for the last 10 years. The high incidence of pulmonary TB (18 to 31/100,000) was detected in populations which were exposed to high concentration of CO (2.7 to 5.2 parts per million, 95% confidence interval [CI]; 1.10 to 1.90) and PM2.5(35 to 42μg/m3; 95% CI 1.03 to 1.80). The level of SO2,NO, and PM10was also high but not significantly related to TB (P > 0.05). Conclusion: The long-term exposure to PM2.5 and CO was positively associated with TB development.

Objectives Antituberculosis drug resistance is increasing among tuberculosis (TB) patients globally, particularly in those who are human immunodeficiency virus (HIV)-positive. The aim of this study was to determine the pattern of anti-TB drug resistance in these patients in an effort to improve successful treatment outcomes with a proper regimen. Methods A cross-sectional study was conducted on adult TB/HIV co-infected patients from 2005–2015. The pattern of anti-TB drug resistance was evaluated among HIV-positive patients with and without a history of TB treatment. Categorisation was made as follows: isoniazid (INH)-resistant; rifampicin (RIF)-resistant; or multidrug-resistant (MDR). Results A total of 52 patients were enrolled in this study (median age 38 years). Among the 52 patients, 18 (34.6%) were MDR-TB patients and the rest were monoresistant TB (resistant either to INH or RIF). INH resistance was the most common resistance pattern (36.5%) noted among patients and was significantly associated with new TB cases (69% vs. 31%; P = 0.01). During TB treatment, 3/48 patients (6.3%) failed treatment and 11/48 (22.9%) died. Patients with MDR-TB were more likely to die during treatment (44.4% vs. 10%; P = 0.011). Conclusions Any drug resistance in previously treated TB cases among HIV-infected patients remains high. The risk of death is increasing in MDR-TB/HIV co-infected patients.

Nontuberculous mycobacteria (NTM) cause significant pulmonary infections in humans. Researchers have reported an association between interferon-gamma receptor-1 (IFN-γR1 or IFNGR1) deficiency and susceptibility to NTM, but the relevance of polymorphism within these genes is not yet clear. In this study, a single nucleotide polymorphism (SNP), T to C, at position-56 in NTM patients with pulmonary disease was investigated. Molecular identification of Mycobacterium isolates was performed with hsp65 genes using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Then, the host genomic DNA from confirmed NTM patients (N = 80) and control subjects (N = 80) were screened for SNPs of IFNGR1 (T-56C) by PCR-RFLP. The results indicated that NTM patients had higher TC (26/80; 32.5%) or CC (46/80; 57.5%) genotypes in comparison with control groups (TC genotypes [22/80, 27.5%]; CC genotypes [6/80, 7.5%]) (P < 0.05). In this regard, all the patients infected with rapid-growing Mycobacterium (RGM, i.e., Mycobacterium chelonae and Mycobacterium fortuitum) had CC genotypes (100%). In contrary, only 50.7% (35/69) of infected patients with slow-growing Mycobacterium (i.e., Mycobacterium simiae, Mycobacterium kansasii, and Mycobacterium avium-intracellulare) had CC genotypes. Thus, patients with CC mutation in IFNGR1 at position-56 are more likely to develop RGM infection. In overall, there is a significant association between SNP of IFNGR1 at position-56 and susceptibility to NTM infection. Based on these data, we propose SNP of IFNGR1 at position-56 as a suitable “biomarker” for identifying populations at higher risk of infection.

Considering the importance of the increasing incidence of non-tuberculous mycobacteria, especially Mycobacterium abscessus worldwide, we conducted a study to evaluate the incidence of these diseases in our area. The aim of this study was to evaluate the prevalence of M. abscessus in patients with non-tuberculous mycobacteria.This descriptive study was performed on 18,083 samples isolated from patients with non-tuberculous mycobacteria during 2011-2017 at the Mycobacteriology Research Center (MRC), Tehran, Iran. To identify the Mycobacterium species, a 439 bp fragment of the IS6110 gene was first amplified using primers TB1 and TB2. Samples with a negative polymerase chain reaction (PCR) result were analyzed to investigate non-tuberculosis mycobacteria (NTM), especially M. abscessus using the RFLP method.Of the 18,083 samples, 5513 (30.49%, 95% CI, 12.95) strains of Complex Tuberculosis and 236 (1.31%, 95% CI, 1.84) strains of NTM were identified. The mean age of the patients with NTM was 18 years, and most of them were male. The most commonly identified species in this study were M. abscessus type Ι 32 (13.56%, 95% CI, 18.36) and M. abscessus type II 13 (5.51%, 95%CI, 20.04).In this study, we observed a high prevalence of Mycobacterium abscessus type 1 in patients. As the treatment protocol for non-TB mycobacteria is different from M. abscessus complex, the diagnosis of these species as soon as possible will be significant for physicians.

Cystic fibrosis (CF) has been generally well defined throughout the world although its prevalence is very difficult to ascertain for a number of reasons, including the fact that the medical/scientific literature and patient registries vary in quality in different countries. In the present review literature (1938–2017), we found out the higher frequency of registered CF patients in the European Union. This could be due to strong clinical awareness and greater health facilities. In contrast, we found a very irregular report from Asian and African countries. In these countries, the national CF registration system is mostly lacking or it is individualized-based research. In this situation, the estimation of various risk factors such as ethnicity and/or races is remained to be resolved. Overall, this review outlines the urgent need for revitalization of national and global CF registration, worldwide.

Aims and Objective: The rapid growth of Mycobacteria (RGM) is a member of Non-tuberculous Mycobacterium that are environmental and opportunistic pathogens whose role in human disease is increasingly recognized. RGMs are highly found in various natural and man-made environmental resources. They can be opportunistically transmitted to humans through contaminated water sources and cause their infectious pulmonary and extrapulmonary infectious diseases. Misdiagnosis of this type of mycobacterium can lead to destructive results. As a result, improper treatment Faced with it can lead to recurrent infections as well as drug resistance. Methods: The aim of this study was to review the existing studies on the prevalence of RGMs between 1990-2017 in worldwide. Data on the prevalence of RGM infection were collected from databases such as PubMed, Web of Science, Cochrane Library, Embase, Scopus, and other scientific databases. Results: In Asia, 776 cases were reported. Among these, the M. furtuitum 23.32% (181,776), and M. chelonae 18.04%(140,776) were the most prevalence, respectively. Also, 105 cases reported in Africa, with the highest prevalence cases being M. fortuitum 46.67%(49,105), M. neoaurium 14.29%(15,105), and M. septicum 8.57% (9,150), respectively. On the other hand, 1363 cases were reported throughout Europe. Among these, the M. furtuitum 30.37% (414,1363), M. chelonae 18.86%(257,1363), and M. peregrinum 13.94%(190,1363) were the most prevalence, respectively. In the United States, 237 cases of RGM were reported, which the highest prevalence was related to the genus M. chelonae 25.32%(60,237), M. mucogenicum 23.63%(56,237) and M. furtuitum 22.36%(53,237), respectively. Also, in Australia 120 cases were observed, with the highest prevalence in M. fortuitum 49.17%(59,120), M. septicum 21.67%(26,120), and M. chelonae 8.33%(10,120), respectively. Conclusion: Given the increasing prevalence of RGMs in different environments, it seems necessary to implement more infection control strategies, appropriate diagnostic methods and control guidelines for NTM diseases. It can be said that we need to increase the quality of diagnostic reference methods and more accurate measures to prevent and control RGM infections.

In this chapter, geographical distribution of nontuberculous mycobacteria both in clinical and environmental isolates are investigated by analyzing the data performed using geographical information system. The distribution of each reported clinical species is analyzed and compared to environmental samples reported within same period of time.

The main aim of this chapter is to describe the informative steps to diagnose Mycobacterium other than tuberculosis (NTM). Although, the death rate from NTM may not be as high as tuberculosis and lepromatous diseases, it was described that the laboratory work engaged in mycobacteriology should follow the standard classification of methods to detect NTM. The information provided here are the standard protocols recommended by the European Society of Mycobacteriology, the American Society of Microbiology, and the World Health Organization.

BACKGROUND: The potential role of environmentalMycobacterium tuberculosisin the epidemiology of TB remains unknown. We investigated the transmission ofM tuberculosisfrom humans to the environment and the possible transmission ofM tuberculosisfrom the environment to humans. METHODS:A total of 1,500 samples were collected from three counties of the Tehran, Iran metropolitan area from February 2012 to January 2014. A total of 700 water samples (47%) and 800 soil samples (53%) were collected. Spoligotyping and the mycobacterial interspersed repetitive units-variable number of tandem repeats typing method were performed on DNA extracted from single colonies. Genotypes ofM tuberculosisstrains isolated from the environment were compared with the genotypes obtained from 55 patients with confirmed pulmonary TB diagnosed during the study period in the same three counties. RESULTS:M tuberculosiswas isolated from 11 of 800 soil samples (1%) and 71 of 700 water samples (10%). T family (56 of 82, 68%) followed by Delhi/CAS (11 of 82, 13.4%) were the most frequentM tuberculosissuperfamilies in both water and soil samples. Overall, 27.7% of isolates in clusters were related. No related typing patterns were detected between soil, water, and clinical isolates. The most frequent superfamily ofM tuberculosisin clinical isolates was Delhi/CAS (142, 30.3%) followed by NEW-1 (127, 27%). The bacilli in contaminated soil (36%) and damp water (8.4%) remained reculturable in some samples up to 9 months. CONCLUSIONS: Although the dominantM tuberculosissuperfamilies in soil and water did not correspond to the dominantM tuberculosisfamily in patients, the presence of circulating genotypes ofM tuberculosisin soil and water highlight the risk of transmission.

Background Tuberculosis (TB) remains a significant global health concern and its diagnosis is challenging due to the limitations in the specificity and sensitivity of the current diagnostic tests. Exosomes are bioactive 30–100 nm vesicles produced by most cell types and are found in almost all human body fluids. Exosomal microRNAs (miRNAs) can transfer biological information between cells and tissues and may act as potential biomarkers in many diseases. In this pilot study, we assessed the miRNA profile of exosomes released from human monocyte-derived macrophages upon infection with Mycobacterium bovis Bacillus Calmette–Guerin (BCG). Methods Human monocytes were obtained from the peripheral blood of three healthy subjects and driven to a monocyte-derived macrophage (MDM) phenotype using standard protocols. MDMs were infected with BCG or left uninfected as control. 72 h post-infection, exosomes were collected from the cell culture medium, RNA was isolated and RNA-seq performed. The raw reads were filtered to eliminate adaptor and primer sequences and the sequences were run against the mature human miRNA sequences available in miRBase. MicroRNAs were identified using an E value

Background and objectives:Isoniazid (INH) is one of the most potent anti-tuberculosis (TB) drugs. The spread and transmission of INH- resistant bacilli are likely to pose a significant problem for National TB control Program (NTP). In this study, we aimed to determine the trend of INH-monoresistant TB in Iran.Methods:The susceptibility patternsof Mycobacterium tuberculosis(MTB) strains that were isolated from clinical samples were retrospectively analyzed (January 2003-December 2011). Identification and drug susceptibility testing (DST) were performed using both conventional and molecular methods. The associated risk factors were assessed using the Chi-square test.Results:Out of 4825 culture-positive isolates, 6.1% were resistant to INH, with an increasing trend over the study period. The INH-monoresistance from 4.4 in 2003 reached to 9.4% in 2011. Among the studied risk factors, age was significantly associated with INH-monoresistance (p < 0.05).Conclusions:The increased trend in INH-monoresistance underlines the need for greater enforcement of national TB control programs. In this regard, better management of TB cases, establishing advanced diagnostic facilities and use of standard treatment regimens are recommended to avoid further emergence of INH resistant cases.

Aims: Detection of drug resistance M. tuberculosisisolates is one of the most important strategies to control the disease. Nowadays, with a dvances in molecular technology, various methods are available todetect drug resistantM. tuberculosisstrains such as those based on capture specific probes. In this study, we aimed to investigate the frequency of mutation in the M. tuberculosis-rpoB gene by Polymerase ChainReaction based on Enzyme Linked Immuno Sorbent Assay (PCR-ELISA) detection. Methodology: Thirty-three culture positive isolates were randomly selected for this study. All the isolates were subjected to a drug Susceptibility Test (DS T) using the proportion method. Then the ability and the efficiency of Multiplex Allele Specific PCR (MAS -PCR) and PCR -ELISA to detect Rif resistant (Rifr) M. tuberculosisisolates was compared and evaluated. OriginalResearch Article

Since there have been no published molecular studies of Pneumocystis jirovecii isolates from Iranian patients, we investigated the genotypes of such isolates recovered from HIV-infected patients, those undergoing cancer chemotherapy and patients with chronic obstructive pulmonary disease (COPD). P. jirovecii typing, based on ITS1 and ITS2 sequence analysis, was performed on 34 isolates from Iranian immunosuppressed patients. In total, 44 genotypes were detected of which relative to ITS1, eight known genotypes (A, B, C, E, G, H, N and O) and one novel sequence were noted. Eight known genotypes (b, c, e, g, h, i, j and n) were also found with ITS2. The most frequent ITS1 and ITS2 genotypes were E (21/44, 47.7%) and g (22/44, 50%), respectively. From determined haplotypes, the four most frequent ones were Eg (11/44, 25%), Gg (5/44, 11.3%), Gi (4/44, 9.1%), Ei (3/44, 6.8%), and Hg (3/44, 6.8%). Two novel haplotypes (Hb and Hi) were also identified, along with mixed infections as seven (20.5%) patients were found to have more than one haplotype. It is suggested that novel haplotypes in Iranian patients may be generated through sexual recombination within the host.

Multidrug-resistant tuberculosis (MDR-TB), caused by drug-resistant strains of Mycobacterium tuberculosis, is an increasingly serious problem worldwide. Here we examined a data set of whole-genome sequences from 5,310 M. tuberculosis isolates from five continents. Despite the great diversity of these isolates with respect to geographical point of isolation, genetic background and drug resistance, the patterns for the emergence of drug resistance were conserved globally. We have identified harbinger mutations that often precede multidrug resistance. In particular, the katG mutation encoding p.Ser315Thr, which confers resistance to isoniazid, overwhelmingly arose before mutations that conferred rifampicin resistance across all of the lineages, geographical regions and time periods. Therefore, molecular diagnostics that include markers for rifampicin resistance alone will be insufficient to identify pre-MDR strains. Incorporating knowledge of polymorphisms that occur before the emergence of multidrug resistance, particularly katG p.Ser315Thr, into molecular diagnostics should enable targeted treatment of patients with pre-MDR-TB to prevent further development of MDR-TB.

This chapter briefly reviews drug resistance in Mycobacterium tuberculosis . The difference of cell wall thickness in M. tuberculosis was demonstrated using atomic and electron micrographs.

This chapter briefly reviews the architecture of the Mycobacterium tuberculosis cell envelope and the compounds that surround the cytoplasm and protect M. tuberculosis from the environment. In addition, it demonstrates the fine structures that transfer the materials in and out of tubercle bacilli.

This chapter demonstrates the morphology of latent Mycobacterium tuberculosis . The cell was isolated from an in vitro and in vivo model of latency. Atomic force micrographs show the nonacid-fast bacilli.

This chapter briefly reviews the taxonomy and nomenclature in Mycobacterium . Ideally, taxonomy is the scientific way or process to group different living things together. There are three distinct aspects of taxonomy: classification, nomenclature, and identification. Classification is the arrangement of organisms into related groups. Nomenclature is the naming of the populations defined and delineated by the rules of the International Code of Nomenclature of Bacteria (ICNB). Identification is the assigning of an unknown strain to a particular taxonomic group. The basic unit in taxonomy is the species. In practice a species is an abstraction that refers to a collection of strains that share many characteristics. In general, a species is an easily recognizable taxon based upon distinctive morphological and physiological characteristics that are described qualitatively rather than quantitatively.

This chapter briefly reviews the variable cell shape in Mycobacterium tuberculosis . The tubercle bacillus does not always manifest itself in the classical rod shape. They can appear as a granular rod, round, Y-, V-, ovoid, and club shapes. These variable shapes can be seen as a marker of virulence, of biological defense against specific immune responses, or of cell division. However, the possible significance of such variant forms with respect to etiology, control, and prognosis of tuberculosis infection is not very clear and needs future investigations.

This chapter briefly reviews the cell division cycle in Mycobacterium tuberculosis . The symmetrical binary fission and unusual type of growth (ie, asymmetrical, budding, and multibranching types of cell divisions) is discussed and presented using atomic and electron micrographs.

Since apoptosis and survival of the immune cells are crucially important in prevention or predisposition of individual from/to infections, especially in intracellular ones, the current study was performed to assess the correlation of host genetic polymorphisms with susceptibility to TB. For this reason, we investigated the difference of the single nucleotide polymorphisms [SNPs] in tumor necrosis factors [TNF-α] genes at (-238, -308, -857 and -863 position) and tumor necrosis factors receptors two [TNFR2] at (T 587 G position) between patients [n=151] and control [n=83]. The genotyping was studied by using PCR-RFLP which had high sensitivity in detecting compared with other techniques. The results showed a strong correlation between two polymorphisms in different loci of TNF-α gene including TNF-α T-857 C and A 238 G. But no association were found in TNFR2 genes with susceptibility to TB. And we found no correlation between TNFR2 and TNF-α gene polymorphisms. Therefore, the TNF-α T 857 C and A 238 G SNPs could be promising marker for identifying risk populations.

Objective/background: The risk of mortality and morbidity among tuberculosis (TB) and human immunodeficiency virus (HIV) coinfected patients is significantly higher than that of patients infected with TB alone. The aim of this study was to evaluate the survival of TB-HIV patients in a TB-referral center during a 10-year follow-up. Methods: All TB-HIV patients in our referral center were enrolled in the study from 2003 to 2014, and patients were divided into two groups: HIV-TB patients without a history of TB treatment (new cases of TB) and HIV-TB patients with a history of TB treatment. Both groups were treated based on World Health Organization TB-treatment guidelines, and multivariate analysis was performed to evaluate risk factors of all-cause mortality. Results: During the study, 22 HIV-TB patients with a history of TB treatment and 263 HIV-TB patients with newly diagnosed TB were included. Baseline demographic and clinical characteristics were similar, except that miliary TB (98% vs. 2%) and mortality (97% vs. 3%; p = 0.06) were more likely in HIV patients with newly diagnosed TB. During TB treatment and subsequent follow-up, two patients did not respond to treatment and 92 (32.3%) patients died, whereas the cure rate was 60%. Pneumothorax [hazard ratio (HR): 3.17], coinfection (herpes zoster, toxoplasmosis, cytomegalovirus infection, Pneumocystis jiroveci, candidiasis, and other opportunistic infection; HR: 1.75), CD4

The risk of death is significantly higher in HIV-infected patients with tuberculosis (TB). This study aims to evaluate the impact of demographic, clinical and laboratory characteristics on the treatment outcome and mortality of TB/HIV co-infected patients in a tertiary TB centre in Iran. In total, 111 patients were recruited from 2004 to 2007. Mycobacteriological studies and demographic, clinical, and laboratory data from all patients were analysed and predictors of unsuccessful outcomes as well as mortality were determined. The mean age for all 111 TB-HIV patients was 38 ± 9 years (range 22–70) and 107 (96.3%) were men; 104 (93.7%) had a history of drug abuse and 96 (86.4%) had a history of imprisonment. The method of HIV transmission was intravenous drug use in 88 (79.3%). Twenty-three (20.7%) had a history of Category 1 (CAT I) TB treatment and six (5.4%) Category 2 (CAT II) treatment. Combination antiretroviral therapy (cART) was given to 48 (43.2%). No significant associations were found between treatment outcomes or mortality and gender, smoking, drug and alcohol abuse, imprisonment, method of transmission, history of CAT I and CAT II treatments, CD4 counts or adverse effects ( P > 0.05). Administration of cART led to significantly better outcomes ( P < 0.001). Lower serum albumin levels and low body weight were significantly associated with mortality.

We describe the efficacy and outcome of standardised second-line anti-tuberculosis (TB) medications during pregnancy. Treatment outcomes of five pregnant women with documented multidrug-resistant TB (MDR-TB) referred to the National Research Institute of Tuberculosis and Lung Diseases from 2003 to 2009 were analysed in two categories, maternal and neonatal. Patients became pregnant during treatment for MDR-TB without any changes in their anti-tuberculosis regimen. None of them had any adverse effects during pregnancy and delivery. No adverse effects were observed in mothers or neonates. The treatment of MDR-TB during pregnancy with a standardised second-line regimen in this study population was safe, with an acceptable rate of treatment success.

Background: The aim of this study was to identify prevalent spoligopatterns of Mycobacterium tuberculosis (MTB) strains within Iran and its neighboring countries. Methods: The spacer oligonucleotide typing (spoligotyping) was performed on 1,742 MTB strains isolated from Iranian and Afghan patients. Subsequently, these results were compared with published results of Pakistan and Turkey. Results: Based on the international spoligotyping database T, Central Asian Strain (CAS), East African-Indian and Latin American and Mediterranean families were prevalent in the region. T was dominant amongIranian (32.3%) and Turkish (36.5%), whereas CAS was more prevalent among Pakistani (61.3%) and Afghan-immigrant (27.4%) TB patients. Conclusion: The majority of strains isolated from Pakistan and Afghanistan belonged to ancient MTB genotypes (principal genetic group, PGG, I). In contrast, in Turkey there was prevalence of modern TB (PGG II and III), whereas in Iran, the prevalence of ancient and modern TB was almost equal. Therefore, Iran may be considered as the connecting geographical location between ancient and modern TB.

Pyrazinamide (PZA) is an important first-line drug used for the short-course treatment of tuberculosis in combination with isoniazid and rifampin. It has been reported that mutations in pncA gene correlate well with PZA resistance depending on the geographic area. On the other hand, different genotypes of Mycobacterium tuberculosis show different affinities to acquire resistance-related mutations. To determine the relative significance of various mutations in the pncA gene in Iranian PZA-resistant M. tuberculosis isolates and to analyze the association of different genotypes of M. tuberculosis with PZA resistance, 34 PZA-resistant M. tuberculosis isolates were analyzed for their pncA mutations using direct sequencing. These isolates were genotyped by IS6110 fingerprinting and spoligotyping methods. Mutations in the pncA gene were identified in 24 of 34 of these isolates (70.58%). No mutations were found in 10 PZA-resistant isolates, which implied that alternative mechanisms of resistance existed in these strains. PZA resistance was strongly (41.2%) associated with multidrug-resistant tuberculosis. Genotyping revealed the Central Asian (CAS) and East-African Indian families as the most prevalent families between PZA-monoresistant isolates versus the Beijing and Haarlem families which were the most frequent families between PZA including multidrug-resistant isolates.

Purpose : The purpose of this study was to understand the molecular epidemiology of tuberculosis in Khorasan province of Iran was studied by spoligotyping 113 Mycobacterium tuberculosis isolates. The spoligotyping results were in comparison to the word Spoligotyping Database of Institute Pasteur de Guadeloupe (SpolDB4). Spoligotyping data from Iran has rarely been described and there is limited information on the major circulating clades of M. tuberculosis in Iran. Materials and Methods: Spoligotyping was performed on 113 M. tuberculosis isolates from Mashhad patients between November 2004 and September 2005. Results: The study found 57 spoligopatterns. 17 clusters and 32 true orphan genotype. The biggest cluster with 13 isolates had not been previously reported. The Beijing genotype was seen in eight (7.1%) isolates. Conclusions: Genotyping and Spoligotyping gives a unifying framework for both epidemiology and evolutionary analysis of M. tuberculosis populations.

Background The study documented the emergence of new forms of resistant bacilli (totally drug-resistant [TDR] or super extensively drug-resistant [XDR] tuberculosis [TB] strains) among patients with multidrug-resistant TB (MDR-TB). Methods Susceptibility testing against first- and second-line drugs was performed on isolated Mycobacterium tuberculosis strains. Subsequently, the strains identified as XDR or TDR M tuberculosis were subjected to spoligotyping and variable numbers of tandem repeats (VNTR). Results Of 146 MDR-TB strains, 8 XDR isolates (5.4%) and 15 TDR isolates (10.3%) were identified. The remaining strains were either susceptible (67%) or had other resistant patterns (20%). Overall, the median of treatments and drugs previously received by MDR-TB patients was two courses of therapy of 15 months' duration with five drugs (isoniazid [INH], rifampicin [RF], streptomycin, ethambutol, and pyrazinamide). The median of in vitro drug resistance for all studied cases was INH and RF. The XDR or TDR strains were collected from both immigrants (Afghan, 30.4%; Azerbaijani, 8.6%; Iraqi, 4.3%) and Iranian (56.5%) MDR-TB cases. In such cases, the smear and cultures remained positive after 18 months of medium treatment with second-line drugs (ethionamide, para-aminosalicylic acid, cycloserine, ofloxacin, amikacin, and ciprofloxacin). Spoligotyping revealed Haarlem (39.1%), Beijing (21.7%), EAI (21.7%), and CAS (17.3%) superfamilies of M tuberculosis . These superfamilies had different VNTR profiles, which eliminated the recent transmission among MDR-TB cases. Conclusions The isolation of TDR strains from MDR-TB patients from different regional countries is alarming and underlines the possible dissemination of such strains in Asian countries. Now the next question is how one should control and treat such cases.

The ultrastructure of the cell wall of extensively drug-resistant (XDR), multidrug-resistant (MDR) and susceptible tuberculosis (TB) bacilli was viewed under transmission electron microscopy (TEM). Under the TEM, marked differences were observed in the thickness of their cell wall: 20.2 ±1.5 and 17.1 ±1.03 nm for the XDR and MDR TB bacilli, respectively, and 15.6 ± 1.3 nm for the susceptible isolates (p < 0.05). In MDR bacilli, thickening of the cell wall was observed in the intermediate electron-transparent layer (ETL) and outer electron-opaque layer, whereas in XDR TB cells the basal peptidoglycan layer was denser and almost fused with the ETL. Five to seven percent of XDR TB bacilli had the appearance of the stationary phase with cell wall thickness ranging from 21 to 26 nm (p < 0.001). Information provided in this study is of significant importance in terms of drug selection for effective treatment of resistant strains.

There is little information on atypical mycobacterium and human T lymphothropic virus Type I (HTLV-I) co-infection. We present the first case of pulmonary M. simiae infection in co-infection with HTLV-1, confirmed by ELISA antibody test and Western Blot. We discuss the clinical characteristics and laboratory tests of the patient and presumptive immunological relation. We propose that in patients with the HTLV infection and pulmonary symptoms and signs compatible with tuberculosis, evaluation for atypical mycobacteriosis may be recommendable.

Objective/Background Mycobacterium tuberculosis (MTB) causes active tuberculosis (TB) in only a small percentage of infected people. In most cases, the infection is clinically latent, where bacilli can persist in human hosts for years without causing disease. Surprisingly, the biology of such persister cells is largely unknown. This study describes the isolation, identification, and whole-genome sequencing (WGS) of latent TB bacilli after 782 days (26 months) of latency (the ability of MTB bacilli to lie persistent). Methods The in vitro double-stress model of latency (oxygen and nutrition) was designed for MTB culture. After 26 months of latency, MTB cells that persisted were isolated and investigated under light and atomic force microscopy. Spoligotyping and WGS were performed to verify the identity of the strain. Results We established a culture medium in which MTB bacilli arrest their growth, reduce their size (0.3–0.1 μm), lose their acid fastness (85–90%) and change their shape. Spoligopatterns of latent cells were identical to original H 37 R v , with differences observed at spacers two and 14. WGS revealed only a few genetic changes relative to the already published H 37 R v reference genome. Among these was a large 2064-bp insertion (RvD6), which was originally detected in both H 37 R a and CDC1551, but not H 37 R v . Conclusion Here, we show cell-wall free cells of MTB bacilli in their latent state, and the biological adaptation of these cells was more phenotypic in nature than genomic. These cell-wall free cells represent a good model for understanding the nature of TB latency.