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Journal of Clinical Microbiology Feb 2001We evaluated the ability of the AccuProbe (Gen-Probe, San Diego, Calif.) to detect Mycobacterium gordonae and Mycobacterium avium complex directly in liquid medium... (Comparative Study)
Comparative Study
We evaluated the ability of the AccuProbe (Gen-Probe, San Diego, Calif.) to detect Mycobacterium gordonae and Mycobacterium avium complex directly in liquid medium flagged positive by the MB/BacT (Organon Teknika Corp., Durham, N.C.). Seventy-one bottles from clinical specimens containing M. gordonae and 34 containing M. avium, confirmed by culture, were tested by direct AccuProbe assay for both organisms after additional incubation for > or = 48 h and centrifugation at 4,500 x g for 15 min. Relative light unit (RLU) values were analyzed using the manufacturer's recommended cutoff of 30,000 RLU and a lower cutoff of 10,000 RLU. Using the 30,000 RLU cutoff, 55 of 71 (77.5%) specimens containing M. gordonae yielded positive results, whereas 28 of 34 (82.3%) M. avium complex specimens were correctly identified by direct probe. No specimens shown by culture to contain either M. gordonae or M. avium complex tested positive with the probe for the opposite organism (100% specificity). When the cutoff was lowered to 10,000 RLU, 67 of 71 M. gordonae (94.4%) and 32 of 34 M. avium complex (94.1%) specimens were correctly identified. This difference was significant for M. gordonae (P = 0.004) but not for M. avium complex (P = 0.26) compared to detection using the recommended RLU cutoff. Specificity was 100% for specimens containing M. gordonae that were tested with the M. avium complex probe using the 10,000 RLU cutoff, whereas specificity for specimens containing M. avium complex tested with the M. gordonae probe was 97%. Using a lower RLU cutoff for determining a positive result using the M. gordonae or M. avium complex probes when testing instrument-positive MB/BacT bottles directly will improve sensitivity without substantially compromising specificity.
Topics: Bacteriology; Chromatography, High Pressure Liquid; Culture Media; Humans; Mycobacterium Infections, Nontuberculous; Mycobacterium avium Complex; Mycobacterium avium-intracellulare Infection; Nontuberculous Mycobacteria; Reproducibility of Results; Sensitivity and Specificity
PubMed: 11158108
DOI: 10.1128/JCM.39.2.570-573.2001 -
BMC Infectious Diseases Mar 2021Nontuberculous mycobacteria (NTM) are environmental bacterium that may cause and/or compound respiratory diseases in humans. There are over a hundred NTM species with...
BACKGROUND
Nontuberculous mycobacteria (NTM) are environmental bacterium that may cause and/or compound respiratory diseases in humans. There are over a hundred NTM species with varying pathogenicity's Therefore, it is necessary to characterize the populations at risk for each species.
METHODS
Demographic (age, sex, and state of residence) and microbiological data from 2014 were extracted from Mississippi, Missouri, and Ohio disease surveillance systems. NTM species with > 50 reports were included in the analysis. Patient sex, age, and incidence rates were generated for each of the following NTM species: M. abscessus, M. avium complex (MAC), M. chelonae, M. fortuitum, M. gordonae, M. kansasii, M. mucogenicum, and M. peregrinum.
RESULTS
Analysis by sex showed that M. chelonae,M. fortuitum, M. gordonae,and M. kansasii had significantly higher rates in males than females. Age was not associated with patient rates for several specific NTM species e.g., M. chelonae. Mississippi had the highest patient' rates for M. avium, M. gordonae, M. kansasii, and M. chelonae. Ohio had the highest patient' rates for M. abscessus, M. mucogenicum, and M. peregrinum. The highest patient's rate for M. fortuitum was observed in Missouri.
CONCLUSION
This study showed that NTM infection occurred more frequently in males. The highest rates were observed in Mississippi for most of the NTMs studied. Age was not a strong risk factor for some of the NTM species.
Topics: Adolescent; Adult; Age Factors; Aged; Aged, 80 and over; Child; Child, Preschool; Databases, Factual; Female; Humans; Infant; Male; Middle Aged; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Prevalence; Risk Factors; Sex Factors; United States; Young Adult
PubMed: 33706712
DOI: 10.1186/s12879-021-05925-y -
BMC Infectious Diseases Jan 2018The non-tuberculous mycobacteria include those mycobacterium species that are not members of the Mycobacterium tuberculosis complex, the causative agent of pulmonary...
BACKGROUND
The non-tuberculous mycobacteria include those mycobacterium species that are not members of the Mycobacterium tuberculosis complex, the causative agent of pulmonary tuberculosis and Mycobacterium leprae. In Zambia, Non-tuberculous Mycobacteria are gaining recognition as pathogens of public health significance. However, there is scanty information on the isolation and speciation of these organisms for better patient management, consequently reducing the burden of these infections. Given the above information, the thrust of this study was to isolate and characterize NTM from humans and water in Namwala district of Zambia.
METHOD
This was a cross-sectional study were 153 individuals with suspected TB were sampled from four health facilities in Namwala district, sputum samples were also collected. Additionally, 149 water samples were collected from different water drinking sources such as Tap water, Borehole water, rivers, wells and streams. Standard TB culture methods were employed to isolate Non-tuberculous Mycobacteria and later 16S-23S internal transcribed spacer region Sequencing was employed to characterize NTM.
RESULTS
Seven (7, 4.6%) NTM species were identified from humans with M. arupense (3, 42.9%) being the most common organism, while twenty three (23, 15.4%) NTM were identified from water with the common species being Mycobacterium gordonae (5, 21.7%). Mycobacterium avium and Mycobacterium fortuitum were both identified from human and water samples.
CONCLUSION
This study has shown the isolation of NTM species from humans and water. The isolation of NTM from drinking water sources could signify a public health risk to humans.
Topics: Cross-Sectional Studies; Humans; Mycobacterium Infections, Nontuberculous; Mycobacterium avium; Mycobacterium fortuitum; Nontuberculous Mycobacteria; Public Health; Sputum; Water Microbiology; Zambia
PubMed: 29310592
DOI: 10.1186/s12879-017-2939-y -
Journal of Clinical Microbiology Jan 2020infection and nontuberculous mycobacteria (NTM) infections exhibit similar clinical symptoms; however, the therapies for these two types of infections are different....
infection and nontuberculous mycobacteria (NTM) infections exhibit similar clinical symptoms; however, the therapies for these two types of infections are different. Therefore, the rapid and accurate identification of and NTM species is very important for the control of tuberculosis and NTM infections. In the present study, a Cas12a/guide RNA (gRNA)-based platform was developed to identify and most NTM species. By designing species-specific gRNA probes targeting the sequence, a Cas12a/gRNA-based platform successfully identified and six major NTM species (, , , , , and ) without cross-reactivity. In a blind assessment, a total of 72 out of 73 clinical isolates were correctly identified, which is consistent with previous sequencing results. These results suggest that the Cas12a/gRNA-based platform is a promising tool for the rapid, accurate, and cost-effective identification of both and NTM species.
Topics: Bacterial Proteins; CRISPR-Associated Proteins; CRISPR-Cas Systems; Endodeoxyribonucleases; Humans; Mycobacterium; Mycobacterium Infections, Nontuberculous; Mycobacterium avium Complex; Mycobacterium tuberculosis; Nontuberculous Mycobacteria; RNA Probes; RNA, Guide, CRISPR-Cas Systems; RNA, Ribosomal, 16S; Sensitivity and Specificity; Tuberculosis
PubMed: 31723010
DOI: 10.1128/JCM.01368-19 -
International Journal of... Jun 2015Pulmonary infections with nontuberculous mycobacteria (NTM) are recognized as a problem in immunodeficient individuals and are increasingly common in older people with... (Review)
Review
Pulmonary infections with nontuberculous mycobacteria (NTM) are recognized as a problem in immunodeficient individuals and are increasingly common in older people with no known immune defects. NTM are found in soil and water, but factors influencing transmission from the environment to humans are mostly unknown. Studies of the epidemiology of NTM disease have matched some clinical isolates of NTM with isolates from the patient's local environment. Definitive matching requires strain level differentiation based on molecular analyses, including partial sequencing, PCR-restriction fragment length polymorphism (RFLP) analysis, random amplified polymorphic DNA (RAPD) PCR, repetitive element (rep-) PCR and pulsed field gel electrophoresis (PFGE) of large restriction fragments. These approaches have identified hospital and residential showers and faucets, hot-tubs and garden soil as sources of transmissible pathogenic NTM. However, gaps exist in the literature, with many clinical isolates remaining unidentified within environments that have been tested, and few studies investigating NTM transmission in developing countries. To understand the environmental reservoirs and transmission routes of pathogenic NTM, different environments, countries and climates must be investigated.
Topics: Environmental Microbiology; Humans; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria
PubMed: 26972876
DOI: 10.1016/j.ijmyco.2015.03.002 -
Clinical Microbiology Reviews Jan 2004Environmental mycobacteria are emerging pathogens causing opportunistic infections in humans and animals. The health impacts of human-mycobacterial interactions are... (Review)
Review
Environmental mycobacteria are emerging pathogens causing opportunistic infections in humans and animals. The health impacts of human-mycobacterial interactions are complex and likely much broader than currently recognized. Environmental mycobacteria preferentially survive chlorination in municipal water, using it as a vector to infect humans. Widespread chlorination of water has likely selected more resistant environmental mycobacteria species and potentially explains the shift from M. scrofulaceum to M. avium as a cause of cervical lymphadenitis in children. Thus, human activities have affected mycobacterial ecology. While the slow growth and hydrophobicity of environmental mycobacteria appear to be disadvantages, the unique cell wall architecture also grants high biocide and antibiotic resistance, while hydrophobicity facilitates nutrient acquisition, biofilm formation, and spread by aerosolization. The remarkable stress tolerance of environmental mycobacteria is the major reason they are human pathogens. Environmental mycobacteria invade protozoans, exhibiting parasitic and symbiotic relationships. The molecular mechanisms of mycobacterial intracellular pathogenesis in animals likely evolved from similar mechanisms facilitating survival in protozoans. In addition to outright infection, environmental mycobacteria may also play a role in chronic bowl diseases, allergies, immunity to other pulmonary infections, and the efficacy of bacillus Calmette-Guerin vaccination.
Topics: Animals; Environmental Microbiology; Eukaryota; Humans; Incidence; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Tuberculosis
PubMed: 14726457
DOI: 10.1128/CMR.17.1.98-106.2004 -
Journal of Infection in Developing... Dec 2019Non-tuberculous mycobacterium (NTM) can colonize the human body, leading to opportunistic infection. This study was conducted to analyze the NTM species composition in a...
INTRODUCTION
Non-tuberculous mycobacterium (NTM) can colonize the human body, leading to opportunistic infection. This study was conducted to analyze the NTM species composition in a primary hospital and investigate the potential features of the patients with different NTM species.
METHODOLOGY
Mycobacterial strains were collected from the patients admitted at the hospital from January 2016 to May 2019. MPB64 assay was used to screen NTM strains and confirmed by Rv0577 amplification. The species were identified by hsp65 sequencing. The clinical records of patients with NTM were retrospectively reviewed.
RESULTS
Among the 122 identified NTM isolates, the most common strains were Mycobacterium avium complex (MAC, n = 102, 83.6%), Mycobacterium abscessus (n = 9, 7.4%) and Mycobacterium lentiflavum (n = 5, 4.1%). The predominant species among MAC were Mycobacterium chimaera (n = 57, 46.7%), followed by Mycobacterium intracellulare (n = 25, 20.5%) and Mycobacterium colombiense (n = 17, 13.9%). A significantly lower percentage of positive acid-fast assay was observed in Mycobacterium colombiense positive patients than in those with Mycobacterium intracellulare and Mycobacterium chimaera. Mycobacterium intracellulare was more frequently isolated in patients from the infectious department than in other MAC members.
CONCLUSIONS
A predominant prevalence of Mycobacterium chimaera in Dongyang of Zhejiang Province was different from other regions in China, indicating that its prevalence has been likely underestimated. The heterogeneity in clinical features, caused by different MAC members, required an accurate species identification of the NTM isolated in the primary hospitals.
Topics: Aged; Aged, 80 and over; China; Cross Infection; Female; Humans; Male; Middle Aged; Molecular Epidemiology; Mycobacterium Infections, Nontuberculous; Mycobacterium avium Complex; Mycobacterium avium-intracellulare Infection; Nontuberculous Mycobacteria; Opportunistic Infections; Retrospective Studies; Species Specificity
PubMed: 32088696
DOI: 10.3855/jidc.11772 -
Antimicrobial Agents and Chemotherapy May 2017The main goal of our study was to evaluate the bedaquiline susceptibility of six prevalent species of pathogenic nontuberculous mycobacteria (NTM) in China. In...
The main goal of our study was to evaluate the bedaquiline susceptibility of six prevalent species of pathogenic nontuberculous mycobacteria (NTM) in China. In addition, we investigated the potential molecular mechanisms contributing to bedaquiline resistance in the different NTM species. Among slowly growing mycobacteria (SGM), bedaquiline exhibited the highest activity against ; the MIC and MIC values were 0.03 and 16 mg/liter, respectively. Among rapidly growing mycobacteria (RGM), subsp. (s) and subsp. () seemed more susceptible to bedaquiline than , with MIC and MIC values of 0.13 and >16 mg/liter, respectively, for both species. On the basis of bimodal distributions of bedaquiline MICs, we proposed the following epidemiological cutoff (ECOFF) values: 1.0 mg/liter for SGM and 2.0 mg/liter for RGM. Among , , , , , and isolates, 14 (29.8%), 41 (27.2%), 33 (39.3%), 44 (20.2%), 42 (25.8%), and 7 (31.8%), respectively, were resistant to bedaquiline. No significant differences in the proportions of bedaquiline resistance among these species were observed ( > 0.05). Genetic mutations were observed in 74 isolates (10.8%), with all nucleotide substitutions being synonymous. In conclusion, our data demonstrate that bedaquiline shows moderate activity against NTM species. Using the proposed ECOFF values, we could distinguish between bedaquiline-resistant and -susceptible strains with the broth dilution method. In addition, no nonsynonymous mutations in the gene that conferred bedaquiline resistance in all six NTM species were identified.
Topics: Antitubercular Agents; Bacterial Proton-Translocating ATPases; Diarylquinolines; Drug Resistance, Bacterial; Humans; Microbial Sensitivity Tests; Mutation; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; RNA, Ribosomal, 16S
PubMed: 28242674
DOI: 10.1128/AAC.02627-16 -
Emerging Infectious Diseases Jul 2017Mycobacterium gordonae is often regarded as a weak pathogen that only occasionally causes overt disease. We report a case of M. gordonae infection in the facial skin,...
Mycobacterium gordonae is often regarded as a weak pathogen that only occasionally causes overt disease. We report a case of M. gordonae infection in the facial skin, nasal mucosa, and paranasal sinus in an immunocompetent patient and review previous cases. The T-SPOT.TB test might be useful in diagnosing such cases.
Topics: Anti-Bacterial Agents; Biopsy; China; Epistaxis; Female; Humans; Middle Aged; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Tomography, X-Ray Computed; Tuberculin Test; Ulcer
PubMed: 28628445
DOI: 10.3201/eid2307.162033 -
Journal of the Formosan Medical... Jun 2020Great progress has recently been made in methodologies for identifying nontuberculous mycobacteria (NTM). Recommendations for drug susceptibility testing (DST) of NTM... (Review)
Review
Great progress has recently been made in methodologies for identifying nontuberculous mycobacteria (NTM). Recommendations for drug susceptibility testing (DST) of NTM have been expanded and updated by the Clinical and Laboratory Standards Institute and are crucial in the management of NTM infections. This article summarizes the clinically relevant molecular methods used to discriminate NTM species and updates the information on DST. Furthermore, recent progress on new antimicrobials against NTM infections is reviewed.
Topics: Anti-Bacterial Agents; Humans; Microbial Sensitivity Tests; Mycobacterium Infections, Nontuberculous; Mycobacterium tuberculosis; Nontuberculous Mycobacteria
PubMed: 32423573
DOI: 10.1016/j.jfma.2020.05.002