Occurrence Of Nontuberculous Mycobacteria Research Articles

Molecular Epidemiologic Investigation of Mycobacterium intracellulare Subspecies chimaera Lung Infections at an Adult Cystic Fibrosis Program.

Rationale: Outbreaks of nontuberculous mycobacteria (NTM) among people with cystic fibrosis (pwCF) have been reported at CF centers with conflicting conclusions. The occurrence of NTM at the UVMC (University of Vermont Medical Center) adult CF program was investigated. Objectives: Use the HALT NTM (Healthcare-associated Links in Transmission of NTM) toolkit to investigate the healthcare-associated transmission and/or acquisition of NTM among pwCF having genetically similar NTM isolates. Methods: Whole genome sequencing of NTM isolates from 23 pwCF was conducted to identify genetically similar NTM isolate clusters (30 or fewer single-nucleotide polymorphism differences). The epidemiological investigation, comparison of respiratory and healthcare environmental isolates, and home residence watershed mapping were analyzed. Results: Whole genome sequencing analysis revealed two clusters of NTM isolates (Mycobacterium avium and M. intracellulare ssp. chimaera) among pwCF. The epidemiologic investigation demonstrated opportunities for healthcare-associated transmission within both clusters. Healthcare environmental M. avium isolates revealed no genetic similarity to respiratory isolates. However, M. intracellulare ssp. chimaera respiratory isolates revealed greater genetic similarity to a hospital water biofilm isolate than to each other. Neither cluster had all subjects residing in the same watershed. Conclusions: This study suggests the healthcare-associated transmission of M. avium among pwCF is unlikely at UVMC but supports the healthcare-associated environmental acquisition of M. intracellulare ssp. chimaera. The presence of genetically similar isolates alone is insufficient to confirm healthcare-associated transmission and/or acquisition. The HALT NTM toolkit standardizes outbreak investigation with genetic analysis, epidemiologic investigation, healthcare environmental sampling, and home of residence watershed identification to test the frequency and nature of healthcare-associated NTM transmission among pwCF.

Occurrence of Non-tuberculous Mycobacteria (NTM) in environmental samples and their characterization

Occurrence of Non-tuberculous Mycobacteria (NTM) in environmental samples and their characterization

Occurrence of Nontuberculous Mycobacteria, Salmonella, Listeria monocytogenes, and Staphylococcus aureus in Artisanal Unpasteurized Cheeses in the State of Michoacan, Mexico

This study investigated the presence of nontuberculous mycobacteria (NTM) for the first time in two types of unpasteurized fresh cheese produced in the state of Michoacan, Mexico. We tested for this pathogen, along with the others, to broaden the study of microbiological quality in 60 samples of cheese, 30 fresh and 30 Adobera, which were collected from six artisanal cheese factories (ACFs). The hygienic conditions of these establishments and the practices of cheese manufacture were generally poor. Although Mycobacterium bovis was not detected, four cheese samples harbored NTM isolates. The four NTM isolates were identified using three molecular markers (hsp65, rrs, and rpoB genes) that corresponded to Mycolicibacterium fortuitum (n = 3) and Mycolicibacterium mageritense (n = 1). All 60 cheese samples analyzed had unsatisfactory microbiological quality according to the Mexican Official Guideline. Regarding fresh cheeses, all 30 samples analyzed were positive for aerobic mesophilic bacteria, total coliforms, fecal coliforms, and yeasts and molds. Escherichia coli and Staphylococcus aureus were present in 23 and 21 samples, respectively. Listeria monocytogenes was identified in a sample and was isolated from a bulk milk tank in the same ACF. With regard to Adobera cheeses, all samples were positive for aerobic mesophilic bacteria, total coliforms, fecal coliforms, yeasts and molds, and S. aureus. E. coli was isolated from 28 samples. Salmonella was isolated from a sample and from a wooden shovel used in the manufacture of the cheeses in the same ACF. Thus, the consumption of unpasteurized fresh cheese may represent a public health risk. Because of this, health authorities should enforce the legislation that forbids the processing of cheese with unpasteurized milk and encourage producers to follow good manufacturing practices from original ingredients, through the production process of the cheese, to its sale to assure a safe product.

Mycobacterium helveticum sp. nov., a novel slowly growing mycobacterial species associated with granulomatous lesions in adult swine.

The occurrence of nontuberculous mycobacteria in different hosts and their implication as obligate or opportunistic pathogens remain mainly unclear. Mycobacteriosis in pigs is usually associated with members of the Mycobacterium avium complex and, in particular, with ‘ Mycobacterium avium subsp. hominissuis ’. Here we describe a novel slow-growing mycobacterial species isolated from lymph nodes obtained from two sows housed in different Swiss farms. The animals presented chronic inappetence and mild diarrhoea. Gross pathology revealed focal caseous lymphadenopathy of the mesenteric lymph nodes. Complete genome sequencing of the two isolates from the two sows was performed. The genomes comprised 5.76 Mb and an average nucleotide identity score of 99.97 %. Whole genome sequence, mycolic acid and matrix-assisted laser desorption ionization-time of flight mass spectrometry analyses revealed that the two isolates were not related to any previously described Mycobacterium species. The closest related species was Mycobacterium parmense , a slow-growing scotochromogenic mycobacterium first isolated from a cervical lymph node of a 3-year-old child. The name proposed for the new species is Mycobacterium helveticum sp. nov. and 16-83T (=DSM 109965T= LMG 2019-02457T) is the type strain.

Changing epidemiology of the respiratory bacteriology of patients with cystic fibrosis–data from the European cystic fibrosis society patient registry

BackgroundMonitoring changes in the epidemiology of cystic fibrosis (CF) pathogens is essential for clinical research, quality improvement, and clinical management. MethodsWe analyzed data reported to the European Cystic Fibrosis Society Patient Registry (ECFSPR) from 2011 to 2016 to determine the overall and the age-specific annual prevalence and incidence of selected CF pathogens and their trends during these years. The ECFSPR collects data on three chronic infections: Pseudomonas aeruginosa (PsA), Burkholderia cepacia complex Species (BCC) and Staphylococcus aureus (SA), as well as on the occurrence of non-tuberculous mycobacteria (NTM) and Stenotrophomonas maltophilia (SM). The same analyses were performed for different country groups, according to their gross national income (GNI). ResultsThe pathogens with the highest prevalence were SA and PsA, with prevalence, in 2016, equal to 38.3% and 29.8% respectively, followed by SM (8.1%). The pathogens with the lowest prevalence were NTM (3.3%) and BCC (3.1%). The overall prevalence and incidence significantly decreased for PsA; they also decreased for BCC, while they increased significantly for SA. The overall prevalence of NTM and SM increased significantly. The most considerable prevalence changes were observed for PsA, which decreased across all income country groups and all age strata (with the exception of 0–1 years) The prevalence and incidence of pathogens differed significantly according to GNI. ConclusionsThe epidemiology of CF pathogens in Europe has changed; epidemiologic data differ significantly among countries with different socio-economic status. The causes of these observations are multifactorial and include improvements in clinical care and infection control.

Changing Epidemiology of the Respiratory Bacteriology of Patients with Cystic Fibrosis - Data from the European Cystic Fibrosis Society Patient Registry

Background: Monitoring changes in the epidemiology of cystic fibrosis (CF) pathogens further improves our understanding of the potential impact of interventions. Methods: We performed a retrospective analysis using data reported to the European Cystic Fibrosis Society Patient Registry (ECFSPR) from 2011 to 2016 to determine the overall and the age specific annual prevalence and incidence of selected CF pathogens and their trends during these years. The ECFSPR collects data on three chronic infections: Pseudomonas aeruginosa (PsA), Burkholderia cepacia complex Species (BCC) and Staphylococcus aureus (SA), as well as on the occurrence of non-tuberculous mycobacteria (NTM) and Stenotrophomonas maltophilia (SM). The same analyses were performed after stratifying for different country groups, according to their gross national income (GNI). Findings: The pathogens with highest prevalence were SA and PsA, with prevalence rates, in 2016, equal to 38.27% and 29.83% respectively, followed by SM (8.14%). The pathogens with lowest prevalence were NTM (3.33%) and BCC (3.13%). The overall prevalence and incidence significantly decreased for PsA; they also decreased non-significantly for BCC, while they increased significantly for SA. The overall prevalence of NTM and SM increased significantly. Among the CF pathogens studied, PsA showed the largest changes in prevalence: it significantly decreased in all age strata, (except 0-1 years) and in all income countries groups. The prevalence and incidence of pathogens differed significantly according to GNI. For PA, BCC and SA the prevalence was significantly higher in lower income groups, while the prevalence and incidence of NTM was higher in countries with the highest income. Interpretation: The epidemiology of CF pathogens in Europe has changed over the 6-year study period; epidemiologic data differ significantly among countries with different socioeconomic status. The causes of these observations are likely multifactorial and include improvements in clinical care and infection prevention and control. Funding: None. Declaration of Interest: We declare that we have no conflicts of interest. Ethical Approval: Scientific and Steering committees of the European Cystic Fibrosis Society Patient Registry.

Non-tuberculous Mycobacteria isolated from lymph nodes and faecal samples of healthy slaughtered cattle and the abattoir environment.

Infections caused by non-tuberculous mycobacteria (NTM) are reported as emerging disease in many countries worldwide. The occurrence of NTM in different hosts and their implication as obligate or opportunistic pathogen remain largely unclear. Lymph nodes and faecal samples of clinically healthy Swiss cattle at slaughter were analysed for the presence of NTM. Based on the examined lymph nodes, NTM were detected in 20% of 108 cattle originating from different premises. The 22 isolates belonged to five different species of Mycobacteria (M.avium subsp. hominissuis, M.kansasii, M.persicum, "M.lymphaticum" and M.europaeum). M.avium subsp. hominissuis (63%) and M.kansasii (18%) thereby predominated and were found in lymph nodes with and without macroscopic changes. Moreover, M.persicum found in two cattle has recently been described as a human pathogen and is closely related to M.kansasii. Amongst cattle with lymph nodes positive for mycobacteria, viable NTM were occasionally also detected in bovine faeces. However, the isolated NTM species from lymph nodes and respective faecal samples (M.hassiacum, M.phlei and M.vaccae) did not coincide. Moreover, NTM species identified amongst isolates from the slaughterhouse environment clearly differed from those from lymph nodes and faecal samples, excluding cross-contamination of the tissue specimens through the environment or laboratory processing. Assuming that some NTM interfere with the detection of bovine tuberculosis (bTB), the present findings in healthy animals emphasize the need of more specific diagnostic tools for bTB eradication programs.

Microbiological Quality and Occurrence of Nontuberculous Mycobacteria in Fresh-Squeezed Orange Juice Samples Purchased from Street Vendors in Mexico City

Nontuberculous mycobacteria (NTM) are potentially pathogenic agents commonly found in a natural ecosystem. For this reason, food is considered another source of NTM transmission for humans. The aims of this study were to evaluate the microbiological quality and the occurrence of NTM in fresh-squeezed orange juice samples purchased from street vendors. All 102 samples analyzed were positive for aerobic mesophilic bacteria (AMB), with limits ranging from 1.8 to 6.2 log CFU/ml. A total of 55 (54%), 25 (25%), and 13 (13%) orange juice samples were positive for total coliforms (TC), fecal coliforms (FC), and Escherichia coli , respectively. TC, FC, and E. coli were present with limits ranging from <3 to >1,100 most probable number (MPN)/ml, <3 to 460 MPN/ml, and <3 to 11 MPN/ml, respectively. Six orange juice samples harbored NTM. These NTM were identified by using three molecular markers (hsp65, rrs, and rpoB genes) and corresponded to the fast-growing mycobacteria: Mycobacterium fortuitum (n = 3), Mycobacterium rhodesiae (n = 1), Mycobacterium obuense (n = 1), and a mixture of M. fortuitum and Mycobacterium mucogenicum in an additional sample (n = 1). No correlation was found between the presence NTM in orange juice samples with the presence and concentration of the indicator microorganisms (aerobic mesophilic bacteria, TC, and FC). Overall, these results suggest that fresh-squeezed orange juice might represent a vehicle for NTM transmission in humans. Therefore, prevention of contamination by humans (proper handling and washing of oranges) during juice preparation should be recommended.

Identification and Susceptibility Testing on Samples of Mycobacterium spp

Background: Tuberculosis is still a major global health problem. Human tuberculosis is caused by species of bacteria belonging to the Mycobacterium genus. In this study we determined mycobacterial species affecting patients from Botucatu, Brazil, and tested M. tuberculosis sensitivity to different drugs. Methods: Data were obtained from Clinical Laboratory Analysis records at Botucatu Medical School University Hospital, UNESP. All samples were processed according to standard isolation procedures from the 2008 Brazil Ministry of Health Mycobacteria Manual, which consist of staining smears by the Ziehl-Neelsen technique and seeding cultures in the Lowenstein-Jensen medium. Results: Samples were isolated from sputum (80.5%), bronchoalveolar lavage (13.8%), pleural fluid (4.6%), and cerebrospinal liquor (1.1%). Smears were evaluated in 87 cases and a total of 59 Short Research Article Calsolari et al.; BJMMR, 7(11): 942-947, 2015; Article no.BJMMR.2015.408 943 patients showed positive smears; 55 from 70 sputum samples and 4 from 12 bronchoalveolar lavage samples. No pleural fluid (4) or cerebrospinal liquor (1) samples showed positive smears. The most commonly identified strain was M. tuberculosis (61 cases); followed by M. avium and M. gordonae 2 cases each, and M. peregrinum and M. abscessus 1 case each. Mycobacteria were not identified in 20 patients. Only two strains of M. tuberculosis were multidrug resistant; one was resistant to isoniazid, rifampicin, and pyrazinamide. These two patients evolved to cure. Conclusion: This study highlights a small but troubling percentage of multidrug resistant samples and reveals the occurrence of nontuberculous mycobacteria, emphasizing the importance of correctly identifying species and testing sensitivity to antibacilar drugs to assure an adequate therapy.

Microbiological Quality of Ready-to-Eat Vegetables Collected in Mexico City: Occurrence of Aerobic-Mesophilic Bacteria, Fecal Coliforms, and Potentially Pathogenic Nontuberculous Mycobacteria

The aims of this study were to evaluate the microbiological quality and the occurrence of nontuberculous mycobacteria (NTM) in a variety of salads and sprouts from supermarkets and street vendors in Mexico City. Aerobic-mesophilic bacteria (AMB) were present in 100% of RTE-salads samples; 59% of samples were outside guidelines range (>5.17 log10 CFU per g). Although fecal coliforms (FC) were present in 32% of samples, only 8% of them exceeded the permissible limit (100 MPN/g). Regarding the 100 RTE-sprouts, all samples were also positive for AMB and total coliforms (TC) and 69% for FC. Seven NTM species were recovered from 7 salad samples; they included three M. fortuitum, two M. chelonae, one M. mucogenicum, and one M. sp. Twelve RTE-sprouts samples harbored NTM, which were identified as M. porcinum (five), M. abscessus (two), M. gordonae (two), M. mucogenicum (two), and M. avium complex (one). Most RTE-salads and RTE-sprouts had unsatisfactory microbiological quality and some harbored NTM associated with illness. No correlation between the presence of coliforms and NTM was found. Overall, these results suggest that RTE-salads and RTE-sprouts might function as vehicles for NTM transmission in humans; hence, proper handling and treatment before consumption of such products might be recommendable.

Occurrence of nontuberculous mycobacteria in aquatic sources of Sri Lanka

Nontuberculous mycobacteria (NTM) have been reported to cause opportunistic infections with increasing frequency, especially in immunocompromised patients. Water plays a major role in the epidemiology of nontuberculous mycobacterial infection in humans, as it is one of the natural sources for transmission of this group of organisms. The current study focused on determining the occurrence of NTM in different aquatic sources of Sri Lanka by using phenotypic tests and polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP) analysis of the rpoβ gene. Of 290 water samples, 45 (15%) were positive for NTM on culture. The percentage of mycobacteria identified at species level by phenotypic tests and PCR–RFLP analysis were 44% (20/45) and 73% (33/45), respectively. The frequency of isolation of mycobacteria from aquarium water, surface water, ground water and chlorinated water were 29% (20/70), 26% (20/76), 5% (4/76) and 1% (1/68), respectively. Eleven different NTM species were identified by PCR–RFLP analysis. M. fortuitum type I was the most frequently isolated species from all the four water sources. The current study suggests that water is an environmental source harboring NTM, a potential public health hazard especially for those with immunodeficiency.

English

Respiratory infections are the major cause of morbidity and mortality in persons with HIV infection. It is clear that with the progression of HIV infection, the function of pulmonary immunocompetent cells declines. There is severe reduction in concentration of pulmonary CD4 cells and impaired cytolytic activity 1 . About 70% of HIV/AIDS patients with infection experience a pulmonary opportunistic infection in life time. Three most important and common pulmonary manifestations of HIV are bacterial pneumonia, tuberculosis and Pneumocystis carinii pneumonia. These comprise more than 90% of opportunistic infections worldwide2. The pandemic of AIDS and the evidence of an association with tuberculosis is now of serious concern. The life time risk of developing tuberculosis for people not infected with HIV is 5 - 10% and this rises to 50% if they are co-infected with HIV. Tubercular pulmonary involvement occurs in 74 to 100% of patients with HIV infection 3 . AIDS pandemic has reversed many of the hard won gains in the tuberculosis control in developed as well as developing countries like India 4. Nontuberculous mycobacterial species (NTM) are common environmental organisms and occasional colonizers of the human respiratory system. The immunosuppressed individuals infected by human immunodeficiency virus (HIV) infection have become the most significant risk factor for disseminated NTM disease and of these, 95% are due to Mycobacterium avium complex. In developed countries, as the incidence of tuberculosis decreased, the occurrence of NTM in pulmonary diseases increased 5. In India infection with non-tuberculous mycobacteria (NTM) is reported to be low as M. tuberculosis is more prevalent and endemic. The infection with NTM is either overlooked by clinicians or in some places facilities are not available for the isolation of NTM. 6

Mycobacterium mucogenicum and other non-tuberculous mycobacteria in potable water of a trauma hospital: a potential source for human infection

This study examined the frequency of occurrence of non-tuberculous mycobacteria (NTM) in potable water samples from a main trauma hospital in Mexico City. Sixty-nine potable water samples were collected, 23 from each source: cistern, kitchen tap and bathroom showers. Of the 69 samples, 36 harboured NTM species. Twenty-nine of the 36 isolates were Mycobacterium mucogenicum, two Mycobacterium rhodesiae, one Mycobacterium peregrinum, one Mycobacterium fortuitum and three were Mycobacterium spp. Hospital potable water harbouring NTM represents a potential source for nosocomial infections, therefore we suggest that hospital potable water microbiological guidelines should include testing for NTM species.

Non-tuberculous mycobacteria and microbial populations in drinking water distribution systems.

Data on the occurrence of non-tuberculous mycobacteria (NTM), in parallel with those obtained for bacterial indicators and amoebae, are presented with the aim to collect information on the spread of NTM in drinking water distribution systems in Italy. Samples were collected from taps of hospitals and households in Central and Southern Italy. The concentration values obtained for the more traditional microbial parameters complied with the mandatory requirements for drinking water. Conversely, moderate-to-high microbial loads (till 300 CFU/L) were observed for the NTM. Positive samples were obtained from 62% of the investigated water samples. Analogous results were observed for amoebae showing a higher percentage of positive samples (76%). In terms of public health, the presence of mycobacteria in water distribution systems may represent a potential risk especially for vulnerable people such as children, the elderly or immunocompromised individuals.

Incidence of nontuberculous mycobacteria in four hot water systems using various types of disinfection

The objective of this study was to determine the incidence of nontuberculous mycobacteria (NTM) in hot water systems of 4 selected hospital settings. The hospitals provided the following types of disinfection for their hot water systems: hydrogen peroxide and silver, thermal disinfection, chlorine dioxide, and no treatment (control). In each building, 6 samples were collected from 5 sites during a 3 month period. NTM were detected in 56 (46.7%) of 120 samples; the CFU counts ranged from 10 to 1625 CFU/L. The detected NTM species were the pathogens Mycobacterium kansasii, Mycobacterium xenopi, and Mycobacterium fortuitum and the saprophyte Mycobacterium gordonae. The most common to be isolated was M. xenopi, which was present in 51 samples. The hot water systems differed significantly in the incidence of NTM. NTM were not detected in the system treated by thermal disinfection, and a relatively low incidence (20% positive samples) was found in the system disinfected with chlorine dioxide. However, a high incidence was found in the control system with no additional disinfection (70% positives) and in the system using hydrogen peroxide and silver (97% positives). Water temperatures above 50 degrees C significantly limited the occurrence of NTM.

Occurrence of nontuberculous mycobacteria in environmental samples.

Nontuberculous mycobacteria (NTM) are a major cause of opportunistic infection in immunocompromised hosts. Because there is no evidence of person-to-person transmission and NTM have been found in drinking water, the environment is considered a likely source of infection. In this study the widespread occurrence of NTM was examined in drinking water, bottled water, and ice samples. A total of 139 samples were examined for NTM by a membrane filtration culture technique followed by PCR amplification and 16S rRNA sequence determination to identify the isolates. NTM were not detected in bottled water or cisterns but were detected in 54% of the ice samples and 35% of the public drinking-water samples from 21 states. The most frequently occurring isolate was M. mucogenicum (formerly referred to as an M. chelonae-like organism).