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Emerging Infectious Diseases Aug 2023Nontuberculous mycobacteria (NTM) infections are caused by environmental exposure. We describe spatial distribution of NTM infections and associations with... (Review)
Review
Nontuberculous mycobacteria (NTM) infections are caused by environmental exposure. We describe spatial distribution of NTM infections and associations with sociodemographic factors and flooding in Missouri, USA. Our retrospective analysis of mycobacterial cultures reported to the Missouri Department of Health and Social Services surveillance system during January 1, 2008-December 31, 2019, detected geographic clusters of infection. Multilevel Poisson regression quantified small-area geographic variations and identified characteristics associated with risk for infection. Median county-level NTM infection rate was 66.33 (interquartile range 51-91)/100,000 persons. Risk of clustering was significantly higher in rural areas (rate ratio 2.82, 95% CI 1.90-4.19) and in counties with >5 floodings per year versus no flooding (rate ratio 1.38, 95% CI 1.26-1.52). Higher risk for NTM infection was associated with older age, rurality, and more flooding. Clinicians and public health professionals should be aware of increased risk for NTM infections, especially in similar environments.
Topics: Humans; Missouri; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Prevalence; Retrospective Studies; Risk Factors; Age Factors; Floods; Rural Population; Male; Female; Middle Aged; Aged; Disease Hotspot
PubMed: 37486160
DOI: 10.3201/eid2908.230378 -
Frontiers in Immunology 2021Autophagy is critically involved in host defense pathways through targeting and elimination of numerous pathogens autophagic machinery. Nontuberculous mycobacteria... (Review)
Review
Autophagy is critically involved in host defense pathways through targeting and elimination of numerous pathogens autophagic machinery. Nontuberculous mycobacteria (NTMs) are ubiquitous microbes, have become increasingly prevalent, and are emerging as clinically important strains due to drug-resistant issues. Compared to (Mtb), the causal pathogen for human tuberculosis, the roles of autophagy remain largely uncharacterized in the context of a variety of NTM infections. Compelling evidence suggests that host autophagy activation plays an essential role in the enhancement of antimicrobial immune responses and controlling pathological inflammation against various NTM infections. As similar to Mtb, it is believed that NTM bacteria evolve multiple strategies to manipulate and hijack host autophagy pathways. Despite this, we are just beginning to understand the molecular mechanisms underlying the crosstalk between pathogen and the host autophagy system in a battle with NTM bacteria. In this review, we will explore the function of autophagy, which is involved in shaping host-pathogen interaction and disease outcomes during NTM infections. These efforts will lead to the development of autophagy-based host-directed therapeutics against NTM infection.
Topics: Animals; Anti-Bacterial Agents; Autophagy; Biological Evolution; Drug Resistance, Bacterial; Host-Pathogen Interactions; Humans; Immunity, Innate; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria
PubMed: 34552591
DOI: 10.3389/fimmu.2021.728742 -
International Journal of Molecular... Jun 2020Over the last years, nontuberculous mycobacteria (NTM) have emerged as important human pathogens. Infections caused by NTM are often difficult to treat due to an... (Review)
Review
Over the last years, nontuberculous mycobacteria (NTM) have emerged as important human pathogens. Infections caused by NTM are often difficult to treat due to an intrinsic multidrug resistance for the presence of a lipid-rich outer membrane, thus encouraging an urgent need for the development of new drugs for the treatment of mycobacterial infections. Efflux pumps (EPs) are important elements that are involved in drug resistance by preventing intracellular accumulation of antibiotics. A promising strategy to decrease drug resistance is the inhibition of EP activity by EP inhibitors (EPIs), compounds that are able to increase the intracellular concentration of antimicrobials. Recently, attention has been focused on identifying EPIs in mycobacteria that could be used in combination with drugs. The aim of the present review is to provide an overview of the current knowledge on EPs and EPIs in NTM and also, the effect of potential EPIs as well as their combined use with antimycobacterial drugs in various NTM species are described.
Topics: Anti-Bacterial Agents; Drug Resistance, Bacterial; Drug Synergism; Humans; Membrane Transport Proteins; Microbial Sensitivity Tests; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Small Molecule Libraries
PubMed: 32545436
DOI: 10.3390/ijms21124191 -
Epidemiology and Infection Dec 2022A cross-sectional and retrospective study of patients with spp. in a Portuguese tertiary hospital, in 2009 and 2019, was performed to understand better the rise in...
A cross-sectional and retrospective study of patients with spp. in a Portuguese tertiary hospital, in 2009 and 2019, was performed to understand better the rise in isolations of nontuberculous mycobacteria (NTM). The number of patients with positive samples for spp. grew from 56 in 2009 to 83 in 2019. The proportion of NTM rose from 39.3% to 49.4% ( = 0.240), with being more frequent in 2009 and in 2019, and decreased from 60.7% to 50.6%. Higher age was associated with NTM in both years, and pulmonary disease and immunosuppression were associated with NTM in 2019 ( < 0.05), with weak to moderate correlation ( = 0.231-0.343). The overall rise of NTM, allied to their known capacity to resist antimicrobial therapy, alerts clinicians to the importance of recognising potential risk factors for infection and improving future prevention strategies.
Topics: Humans; Nontuberculous Mycobacteria; Mycobacterium Infections, Nontuberculous; Retrospective Studies; Cross-Sectional Studies; Mycobacterium avium Complex; Mycobacterium
PubMed: 36503567
DOI: 10.1017/S0950268822000899 -
Drug Discovery Today Aug 2018Incidence of pulmonary diseases caused by non-tuberculous mycobacteria (NTM), relatives of Mycobacterium tuberculosis, is increasing at an alarming rate, surpassing... (Review)
Review
Incidence of pulmonary diseases caused by non-tuberculous mycobacteria (NTM), relatives of Mycobacterium tuberculosis, is increasing at an alarming rate, surpassing tuberculosis in many countries. Current chemotherapies require long treatment times and the clinical outcomes are often disappointing. There is an urgent medical need to discover and develop new, more-efficacious anti-NTM drugs. In this review, we summarize the current status of NTM drug development, and highlight knowledge gaps and scientific obstacles in NTM drug discovery. We propose strategies to reduce biological uncertainties and to begin to populate a NTM drug pipeline with attractive leads and drug candidates.
Topics: Animals; Anti-Bacterial Agents; Drug Discovery; Drug Resistance, Bacterial; Humans; Molecular Structure; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Structure-Activity Relationship
PubMed: 29635026
DOI: 10.1016/j.drudis.2018.04.001 -
Memorias Do Instituto Oswaldo Cruz 2022Non-tuberculous mycobacteria (NTMs) cause diseases known as mycobacteriosis and are an important cause of morbidity and mortality. The diagnosis of pulmonary disease...
BACKGROUND
Non-tuberculous mycobacteria (NTMs) cause diseases known as mycobacteriosis and are an important cause of morbidity and mortality. The diagnosis of pulmonary disease caused by NTM is hampered by its clinical similarity with tuberculosis (TB) and by the lack of an accurate and rapid laboratory diagnosis.
OBJECTIVES
Detect DNA from NTMs directly from lung samples using real-time polymerase chain reaction (qPCR) for amplification of 16S rRNA. Additionally, DNA sequencing (hsp65 and rpoB genes) was used to identify the species of MNTs.
METHODS
A total of 68 sputum samples (54 with suspected NTMs and 14 with TB) from patients treated at a referral hospital were used.
FINDINGS
Of these, 27/54 (50%) were qPCR positive for NTMs and 14/14 TB patients (controls) were qPCR negative with an almost perfect concordance (Kappa of 0.93) with the Mycobacterium spp. culture. Sequencing confirmed the presence of NTM in all positive samples. The most common species was Mycobacterium gordonae (33%), followed by Mycobacterium abscessus (26%), Mycobacterium fortuitum (22%), Mycobacterium avium (15%) and Mycobacterium peregrinum (4%).
MAIN CONCLUSIONS
The qPCR technique for detecting NTMs targeting 16S rRNA has the potential to detect NTMs and rapidly differentiate from Mycobacterium tuberculosis. However, it is necessary to identify the species to help in the differential diagnosis between disease and contamination, and to guide the choice of the therapeutic scheme.
Topics: Humans; Lung; Mycobacterium Infections, Nontuberculous; Mycobacterium tuberculosis; Nontuberculous Mycobacteria; RNA, Ribosomal, 16S; Real-Time Polymerase Chain Reaction; Tuberculosis
PubMed: 35920498
DOI: 10.1590/0074-02760220031 -
Canadian Respiratory Journal 2017Nontuberculous Mycobacteria (NTM) are causing growing health problems worldwide. This is indicated by an increasing amount of scientific reports showing not only... (Review)
Review
Nontuberculous Mycobacteria (NTM) are causing growing health problems worldwide. This is indicated by an increasing amount of scientific reports showing not only well-identified species reemerging but also emergence of new species. The emergence and reemergence of NTM are particularly worrying in developing countries due to scarce published data and improper identification. Here we aimed to examine the main epidemiological aspects and diagnostic challenges associated with NTM in countries of the Gulf Cooperation Council (GCC) and compare these findings to the international arena findings. Data revealed that countries of the GCC are largely dominated by rapidly growing mycobacteria species such as (29%) and (17%) with high rate of definitive respiratory diseases. On the other hand, most of the developed countries are dominated by slowly growing mycobacteria such as MAC, , and . More efforts are needed, however, to gain insights into NTM issues in countries of the GCC.
Topics: Environmental Microbiology; Humans; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Pneumonia, Bacterial; Saudi Arabia
PubMed: 28348502
DOI: 10.1155/2017/5035932 -
Journal of Clinical Microbiology May 2019This minireview provides an update on recent taxonomic changes for the genus with an emphasis on newly identified species isolated from humans or associated with human... (Review)
Review
This minireview provides an update on recent taxonomic changes for the genus with an emphasis on newly identified species isolated from humans or associated with human disease.
Topics: Humans; Mycobacterium; Mycobacterium Infections; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Phylogeny
PubMed: 30602442
DOI: 10.1128/JCM.01408-18 -
BMC Pulmonary Medicine Sep 2015Nontuberculous mycobacteria are well known to be a cause of hot tub lung, however, to our knowledge, there exists no case report of humidifier lung induced by...
BACKGROUND
Nontuberculous mycobacteria are well known to be a cause of hot tub lung, however, to our knowledge, there exists no case report of humidifier lung induced by mycobacteria.
CASE PRESENTATION
A case of a nonimmunocompromised female patient with Mycobacterium gordonae-induced humidifier lung is described. She spontaneously recovered after discontinuing ultrasonic humidifier use. When subjected to a provocation test, she demonstrated acute respiratory distress with signs and symptoms, consistent with hypersensitivity pneumonitis. Before and after the provocation test, water in the humidifier reservoir revealed only Mycobacterium gordonae by the microbiologic analyses.
CONCLUSION
To our knowledge, this is the first report of humidifier lung induced by nontuberculous mycobacteria. Although nontuberculous mycobacteria are well-known to be agents of hot tub lung or metal working fluid lung, physicians should also consider the pathogen as a cause of hypersensitivity lung reaction associated with humidifier use.
Topics: Aged, 80 and over; Alveolitis, Extrinsic Allergic; Bronchial Provocation Tests; Female; Humans; Humidifiers; Lung; Nontuberculous Mycobacteria; Tomography, X-Ray Computed; Water Microbiology
PubMed: 26420433
DOI: 10.1186/s12890-015-0107-y -
BMC Infectious Diseases Mar 2024Nontuberculous mycobacteria (NTM) are environmental bacteria which may cause chronic lung disease. The prevalence of NTM pulmonary infection and disease has been...
BACKGROUND
Nontuberculous mycobacteria (NTM) are environmental bacteria which may cause chronic lung disease. The prevalence of NTM pulmonary infection and disease has been increasing in the United States and globally. The predominant clinically relevant species of NTM in the United States are Mycobacterium avium complex (MAC) species and Mycobacterium abscessus. With the development of rapid species identification methods for NTM (e.g. PCR probes), more testing for NTM is being conducted through commercial labs, such as Laboratory Corporation of America (Labcorp), which provides deidentified real-time testing data to the Centers for Disease Control (CDC) pursuant to a data sharing agreement. Because NTM lung infections are not reportable in most states, other data sources are key to understanding NTM testing patterns, positivity rates, and species distributions to track infection trends and identify clinical care needs.
METHODS
We obtained national Labcorp data for the period January 2019 through mid-April 2022. We subset the data to only respiratory samples sent for Acid Fast Bacilli (AFB) cultures. NTM positive results were defined as those which identified an NTM species and are not Mycobacterium tuberculosis, Mycobacterium bovis, or Mycobacterium gordonae.
RESULTS
Overall, 112,528 respiratory samples were sent for AFB testing during the study period; 26.3% were from the Southeast U.S., identified as HSS Region IV in the Labcorp dataset, and 23.0% were from the Pacific and South Pacific region (Region IX). The culture positive prevalence ranged from 20.2% in the Southeast to 9.2% in the East North Central region (Region V). In the Southeast US, M. abscessus prevalence was 4.0%. For MAC, the highest prevalence was observed in the Mountain region (Region VII) (13.5%) and the lowest proportion was in the East South Central region (7.3%, Region III). Among positive tests, the proportion which was MAC varied from 61.8% to 88.9% and was highest in the Northeast U.S. The proportion of positive samples which were M. abscessus ranged from 3.8% to 19.7% and was highest in the Southeast.
CONCLUSIONS
The Southeastern region of the U.S. has the highest rate of culture positivity in Labcorp tests for total NTM and, of all positive tests, the highest proportion of M. abscessus. These estimates may underrepresent the true number of M. abscessus infections because M. absesscus-specific probes are not commercially available and not all NTM testing in the United States is done by Labcorp. Analysis of real-time testing data from commercial laboratories may provide insights into risk factors for NTM culture positivity in 'hotspot' areas.
Topics: United States; Humans; Nontuberculous Mycobacteria; Mycobacterium avium Complex; Mycobacterium abscessus; Laboratories; Mycobacterium bovis; Opportunistic Infections
PubMed: 38448840
DOI: 10.1186/s12879-024-09059-9