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Biomedical and Environmental Sciences :... May 2017We performed molecular identification of clinical isolates of Mycobacterium fortuitum (M. fortuitum) and conducted drug susceptibility testing to analyze the in vitro...
We performed molecular identification of clinical isolates of Mycobacterium fortuitum (M. fortuitum) and conducted drug susceptibility testing to analyze the in vitro susceptibility of clinical M. fortuitum isolates and potential molecular mechanism conferring resistance to fluoroquinolone and macrolide drugs. The results showed that moxifloxacin had the highest in vitro activity against M. fortuitum, and most M. fortuitum isolates were resistant to clarithromycin and linezolid in China. The loss of genetic mutation in clarithromycin- and amikacin-resistant isolates indicates that some other intrinsic mechanism conferring clarithromycin and amikacin resistance plays an essential role in M. fortuitum infection.
Topics: Antitubercular Agents; China; Drug Resistance, Bacterial; Microbial Sensitivity Tests; Mycobacterium fortuitum
PubMed: 28549494
DOI: 10.3967/bes2017.049 -
Antimicrobial Agents and Chemotherapy Jun 2019The understanding of species distribution and inducible macrolide resistance in the complex (MFC) is limited. Of 90 mostly respiratory MFC clinical isolates, half were...
The understanding of species distribution and inducible macrolide resistance in the complex (MFC) is limited. Of 90 mostly respiratory MFC clinical isolates, half were , followed by , , , and Most , , and isolates were inducibly resistant to clarithromycin, whereas two-thirds of the isolates were clarithromycin susceptible. Clarithromycin-resistant isolates exhibited common mutations of (39), potentially involved in clarithromycin resistance.
Topics: Anti-Bacterial Agents; Clarithromycin; Drug Resistance, Bacterial; Microbial Sensitivity Tests; Mycobacterium fortuitum
PubMed: 30885902
DOI: 10.1128/AAC.02331-18 -
Pulmonology Feb 2022Nontuberculous mycobacteria (NTM) are opportunistic human pathogens found in the environment. The transmission seems to be associated with inhalation of aerosol...
INTRODUCTION AND OBJECTIVES
Nontuberculous mycobacteria (NTM) are opportunistic human pathogens found in the environment. The transmission seems to be associated with inhalation of aerosol droplets, ingestion or trauma events. Recent studies indicate that NTM disease is increasing worldwide, however, the true clinical impact of NTM infections is difficult to determine due to challenges in discriminating between disease and colonization as they are ubiquitous in the environment. In addition, understanding the epidemiology of NTM is difficult and has not yet been established. In this work, we used a country NTM representative collection from the National Reference Laboratory for Tuberculosis (NRL-TB) of the National Institute of Health (INSA), to characterize the circulation trends of NTM species in Portugal and the most affected regions, contributing to a better understanding of the NTM epidemiology.
MATERIAL AND METHODS
We conducted a nationwide retrospective study where all individuals with positive NTM cultures at the NRL-TB of the INSA from 2014 to December 2020 were included. Positive cultures were identified using GenoType Mycobacterium CM/AS® (Hain Lifescience) according to manufacturer's instructions, or hsp65 DNA sequencing as previously described. Social-demographic data from patients were also analyzed and patients classified into 3 groups according only to microbiological data, "definite NTM disease", "NTM colonization" and, "possible NTM disease".
RESULTS
In the period 2014-2020, the NRL-TB performed 50397 cultures. Among these, 1118 cultures were NTM positive retrieved from 944. Most of our cases were in patients whose mean age was 64±15.9 years, and no significant differences between gender was observed, although more frequent in male patients. Overall, from the 944 cases, we were able to identified 93 "definite NTM disease" cases and 79 "possible NTM disease". Mycobacterium avium complex (MAC) (40,8%), Mycobacterium abscessus-chelonae complex (MABC) (9,6%) and Mycobacterium fortuitum (6,3%) were responsible for most of the infections. The geographical distribution of NTM cases varied significantly and was possible to observe that was independent of population density. The region were most cases occurred was Lisbon Metropolitan Area (31,9%), followed by North (25,3%) and Centre (24,4%), however North region has the highest number of "definite NTM disease" cases (n=33).
CONCLUSIONS
This is the first national wide epidemiological study on this subject, contributing to a better understanding of NTM dynamics in Portugal. MAC was the NTM species responsible for the majority of infections and, LMA the region with the highest number of cases. It was also possible to conclude that the number of NTM isolates is independent of the demography of the region.
PubMed: 35219623
DOI: 10.1016/j.pulmoe.2022.01.011 -
Brazilian Journal of Microbiology :... 2013Polycyclic aromatic hydrocarbons (PAH) are carcinogenic compounds which contaminate water and soil, and the enzymes can be used for bioremediation of these environments....
Polycyclic aromatic hydrocarbons (PAH) are carcinogenic compounds which contaminate water and soil, and the enzymes can be used for bioremediation of these environments. This study aimed to evaluate some environmental conditions that affect the production and activity of the catechol 1,2-dioxygenase (C12O) by Mycobacterium fortuitum in the cell free and immobilized extract in sodium alginate. The bacterium was grown in mineral medium and LB broth containing 250 mg L(-1) of anthracene (PAH). The optimum conditions of pH (4.0-9.0), temperature (5-70 °C), reaction time (10-90 min) and the effect of ions in the enzyme activity were determined. The Mycobacterium cultivated in LB shown higher growth and the C12O activity was two-fold higher to that in the mineral medium. To both extracts the highest enzyme activity was at pH 8.0, however, the immobilized extract promoted the increase in the C12O activity in a pH range between 4.0 and 8.5. The immobilized extract increased the enzymatic activity time and showed the highest C12O activity at 45 °C, 20 °C higher than the greatest temperature in the cell free extract. The enzyme activity in both extracts was stimulated by Fe(3+), Hg(2+) and Mn(2+) and inhibited by NH(4+) and Cu(2+), but the immobilization protected the enzyme against the deleterious effects of K(+) and Mg(2+) in tested concentrations. The catechol 1,2-dioxygenase of Mycobacterium fortuitum in the immobilized extract has greater stability to the variations of pH, temperature and reaction time, and show higher activity in presence of ions, comparing to the cell free extract.
PubMed: 24159319
DOI: 10.1590/S1517-83822013000100043 -
Journal of Clinical Tuberculosis and... Dec 2021Optimal management of infection with mycobacterial species requires accurate identification down to complex/species level due to variations in outcomes. Over the last...
Optimal management of infection with mycobacterial species requires accurate identification down to complex/species level due to variations in outcomes. Over the last few decades, there have been significant advances in laboratory diagnostics with development of newer and rapid molecular methods. Here we describe a case of that was misidentified as by DNA line probe assay.
PubMed: 34522793
DOI: 10.1016/j.jctube.2021.100268 -
Animals : An Open Access Journal From... Nov 2022Mycobacteriosis is an important disease that affects captive and wild aquatic fish. Syngnathids are susceptible to infection by non-tuberculous mycobacteria. The aim of...
Mycobacteriosis is an important disease that affects captive and wild aquatic fish. Syngnathids are susceptible to infection by non-tuberculous mycobacteria. The aim of this study was to describe clinical signs, and macroscopic and histological lesions in 25 syngnathids and the molecular characterization of the causative mycobacteria. Clinical presentation ranged from sudden death to non-specific signs, including anorexia, poor body condition, weight loss and marked dyspnea with increased respiratory effort and rate. Gross lesions were mostly ulcers on the tail and small white nodules in the liver, coelomic cavity and inside the eye. The most affected organs were gills, liver, intestine and coelomic mesentery. Microscopic lesions consisted of areas of multifocal to diffuse granulomatous inflammation and bacterial emboli with numerous intralesional acid-fast bacilli. Epithelioid cells, multinucleated giant cells, lymphocytes and fibrous connective tissue, which are commonly observed in granulomatous inflammation, were not observed here. In the real-time PCR, , and common primers, spp. were detected in 4, 7 and 14 individuals, respectively. In addition, this is the first description of mycobacteriosis found in .
PubMed: 36496780
DOI: 10.3390/ani12233259 -
International Journal of... 2022Mycobacterial fatty acid synthase Type-II (FAS-II) components are major virulence factors exploited as potential targets for developing novel antimycobacterial drugs....
BACKGROUND
Mycobacterial fatty acid synthase Type-II (FAS-II) components are major virulence factors exploited as potential targets for developing novel antimycobacterial drugs. The FAS-II enzyme 3-hydroxyacyl-ACP dehydratase (HadC) is important for biofilm development and pathogenesis of Mycobacterium tuberculosis and other mycobacterial species.
METHODS
Literature review and homology search led to the identification of Mycobacterium fortuitum MFhadC gene. Functional interaction study of MFHadC protein was done using STRING. M. fortuitum MFhadC over-expressing (HS) and knockdown (HA) strains were constructed and validated by expression analysis using quantitative polymerase chain reaction. The strains were analyzed for growth behavior and surface spreading ability. Biofilm formation was assayed through crystal violet assay, viability count, and basic fuchsin staining. In addition, survival of the strains was studied under in vitro nutrient starvation and detergent stress.
RESULTS
STRING analysis showed the interaction of HadC with proteins involved in biofilm formation. The strains HS and HA showed spreading ability on the agarose surface, exhibiting translocation patterns similar to the vector control strain. All three strains showed a similar amount of biofilm formation when analyzed using crystal violet assay, viability count, and basic fuchsin staining. The strains showed no deviation in survival when incubated under nutrient starvation and detergent stress.
CONCLUSION
Our results suggest that MFhadC may not be important for the formation and maintenance of biofilm, a factor critically important in M. fortuitum pathogenicity. However, not essential for survival and growth, MFhadC maintains the viability of M. fortuitum under a nutrient-starved environment. Collectively, MFhadC may not be used as a biofilm-specific marker for M. fortuitum.
Topics: Biofilms; Detergents; Fatty Acid Synthases; Gentian Violet; Humans; Mycobacterium fortuitum; Mycobacterium tuberculosis
PubMed: 35775548
DOI: 10.4103/ijmy.ijmy_46_22 -
The Journal of Molecular Diagnostics :... Mar 2017A new multiplex PCR test was designed to detect Mycobacterium chelonae, Mycobacterium abscessus group, and Mycobacterium fortuitum complex on the BD MAX System. A total...
Detection of Mycobacterium chelonae, Mycobacterium abscessus Group, and Mycobacterium fortuitum Complex by a Multiplex Real-Time PCR Directly from Clinical Samples Using the BD MAX System.
A new multiplex PCR test was designed to detect Mycobacterium chelonae, Mycobacterium abscessus group, and Mycobacterium fortuitum complex on the BD MAX System. A total of 197 clinical samples previously submitted for mycobacterial culture were tested using the new protocol. Samples were first treated with proteinase K, and then each sample was inoculated into the BD MAX Sample Buffer Tube. Extraction and multiplex PCR were performed by the BD MAX System, using the BD MAX ExK TNA-3 extraction kit and BD TNA Master Mix, along with specific in-house designed primers and probes for each target. The limit of detection of each target, as well as specificity, was evaluated. Of 197 clinical samples included in this study, 133 were positive and 60 were negative for mycobacteria by culture, and another 4 negative samples were spiked with M. chelonae ATCC 35752. The new multiplex PCR on the BD MAX had 97% concordant results with culture for M. abscessus group detection, 99% for M. chelonae, and 100% for M. fortuitum complex. The new multiplex PCR test performed on the BD MAX System proved to be a sensitive and specific test to detect M. chelonae, M. abscessus group, and M. fortuitum complex by real-time PCR on an automated sample-in results-out platform.
Topics: Humans; Multiplex Polymerase Chain Reaction; Mycobacterium; Mycobacterium Infections; Mycobacterium chelonae; Mycobacterium fortuitum; Real-Time Polymerase Chain Reaction; Reproducibility of Results; Sensitivity and Specificity
PubMed: 28190461
DOI: 10.1016/j.jmoldx.2016.10.004 -
Microorganisms Nov 2021group (MFG) members are able to cause clinical mycobacteriosis in fish and other animals including humans. , , , , , , , , and were isolated from fish with...
Clinical Relevance and Environmental Prevalence of Group Members. Comment on Mugetti et al. Gene Sequencing and Phylogenetic Analysis: Powerful Tools for an Improved Diagnosis of Fish Mycobacteriosis Caused by Group Members. 2021, , 797.
group (MFG) members are able to cause clinical mycobacteriosis in fish and other animals including humans. , , , , , , , , and were isolated from fish with mycobacteriosis. In other animals only three MFG species have been isolated: from camels' milk, from cutaneous infections often described as "farcy", and from different domestic and wild mammals' species. Out of 17, only 3 MFG species (, and ) have never been reported in humans. A total of eight MFG members (, , , subsp. , , , , and ) have been isolated from both pulmonary and extrathoracic locations. In extrathoracic tissues five MFG species (, , , , and ) have been diagnosed and only one MFG member ( subsp. ) has been isolated from pulmonary infection.
PubMed: 34835470
DOI: 10.3390/microorganisms9112345 -
Case Reports in Nephrology 2014Mycobacterium fortuitum is a ubiquitous, rapidly growing nontuberculous mycobacterium (NTM). It is the most commonly reported NTM in peritoneal dialysis (PD) associated...
Mycobacterium fortuitum is a ubiquitous, rapidly growing nontuberculous mycobacterium (NTM). It is the most commonly reported NTM in peritoneal dialysis (PD) associated peritonitis. We report a case of a 52-year-old man on PD, who developed refractory polymicrobial peritonitis necessitating PD catheter removal and shift to hemodialysis. Thereafter, M. fortuitum was identified in the PD catheter culture and in successive cultures of initial peritoneal effluent and patient was treated with amikacin and ciprofloxacin for six months with a good and sustained clinical response. Months after completion of the course of antibiotics, the patient successfully returned to PD. To our knowledge, this is the first reported case of M. fortuitum peritonitis in the field of polymicrobial PD peritonitis. It demonstrates the diagnostic yield of pursuing further investigations in cases of refractory PD peritonitis. In a systematic review of the literature, only 20 reports of M. fortuitum PD peritonitis were identified. Similar to our case, a delay in microbiological diagnosis was frequently noted and the Tenckhoff catheter was commonly removed. However, the type and duration of antibiotic therapy varied widely making the optimal treatment unclear.
PubMed: 25028616
DOI: 10.1155/2014/323757