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Methods in Molecular Biology (Clifton,... 2024Tuberculosis (TB) is the most common cause of death from an infectious disease. Although treatment has been available for more than 70 years, it still takes too long and...
Tuberculosis (TB) is the most common cause of death from an infectious disease. Although treatment has been available for more than 70 years, it still takes too long and many patients default risking relapse and the emergence of resistance. It is known that lipid-rich, phenotypically antibiotic-tolerant, bacteria are more resistant to antibiotics and may be responsible for relapse necessitating extended therapy. Using a microfluidic system that acoustically traps live mycobacteria, M. smegmatis, a model organism for M. tuberculosis we can perform optical analysis in the form of wavelength-modulated Raman spectroscopy (WMRS) on the trapped organisms. This system can allow observations of the mycobacteria for up to 8 h. By adding antibiotics, it is possible to study the effect of antibiotics in real-time by comparing the Raman fingerprints in comparison to the unstressed condition. This microfluidic platform may be used to study any microorganism and to dynamically monitor its response to many conditions including antibiotic stress, and changes in the growth media. This opens the possibility of understanding better the stimuli that trigger the lipid-rich downregulated and phenotypically antibiotic-resistant cell state.
Topics: Spectrum Analysis, Raman; Mycobacterium smegmatis; Microfluidics; Anti-Bacterial Agents; Acoustics; Lab-On-A-Chip Devices; Microfluidic Analytical Techniques; Humans
PubMed: 38949705
DOI: 10.1007/978-1-0716-3981-8_11 -
International Journal of Pediatric... Jun 2024Cervicofacial lymphadenitis caused by non-tubercular mycobacterial (NTM) infections has the highest infection rate in children. Our objective was to assess patient...
OBJECTIVE
Cervicofacial lymphadenitis caused by non-tubercular mycobacterial (NTM) infections has the highest infection rate in children. Our objective was to assess patient demographics, treatment methods, and the impact of weather and geography on the incidence of disease in patients with NTM cervicofacial lymphadenitis.
METHODS
The Pediatric Health Information System (PHIS) database was queried for data on all patients diagnosed with concurrent cervicofacial lymphadenopathy and NTM infection from 2004 to 2022. We assessed the association between weather patterns and NTM cervicofacial lymphadenitis by collecting monthly weather data from the NOAA National Center for Environmental Information. Incidence rates were calculated by dividing the number of cases by the total hospital discharges during the study period.
RESULTS
Among 47 PHIS hospitals, there were 992 diagnoses of NTM cervicofacial lymphadenitis. The average age at diagnosis was 2 [IQR, 2-4], with 59 % female. Drainage of skin abscesses or lesions was performed for 93 (9.4 %) patients, while 15 (1.5 %) had an excisional procedure of the CPT codes assessed. The most common antibiotics utilized were cephalosporins (28 %), macrolides (27 %), and rifampin (12 %). The most common treatment method was surgery with antibiotics (37 %) followed by no treatment at all (35 %), surgery alone (17 %), and antibiotics alone (10 %). Of the 28 states included in the analysis, Washington (IR: 3.5) and Nebraska (IR: 3.3) had the highest incidence rates (IR) of NTM cervical lymphadenitis. The cases were relatively equally distributed across the different weather seasons within each U.S. geographic region. However, the overall average wind speed was weakly associated with increasing the risk of diagnosis when utilizing a mixed effect zero-inflated negative binomial model (Incidence Ratio: 1.07, 95 % CI: (1.01-1.14), p = 0.035).
CONCLUSIONS
Our results indicate that the most common treatment method utilized in patients within our cohort with NTM cervicofacial lymphadenitis was the concurrent use of surgery and antibiotics. Our results also indicate there may be variation in the incidence rate among different states, but additional studies are needed as our cohort only included approximately 50 % of states within the U.S.
PubMed: 38944979
DOI: 10.1016/j.ijporl.2024.112019 -
Microbiology Spectrum Jun 2024Some naturally occurring compounds, known for their antimicrobial activities, have been employed as food additives. However, their efficacy in treating infections caused...
UNLABELLED
Some naturally occurring compounds, known for their antimicrobial activities, have been employed as food additives. However, their efficacy in treating infections caused by antibiotic-resistant bacteria is yet to be fully explored. Rapidly growing mycobacteria (RGM), a category within nontuberculous mycobacteria (NTM), are prevalent in various environments and can lead to infections in humans. The rise of antimicrobial resistance within RGM is a documented concern. In this study, we reported that four specific natural compounds effectively inhibited the growth and biofilm formation of three key RGM pathogens , , and . We screened 12 natural compounds for their effectiveness against antibiotic-resistant clinical strains of RGM. Four compounds showed significant inhibitory effects from the most effective to least: -cinnamaldehyde, carvacrol, gentisaldehyde, and phloroglucinaldehyde. In the analysis of time-killing kinetics, gentisaldehyde and phloroglucinaldehyde displayed bactericidal activity while -cinnamaldehyde and carvacrol exhibited bacteriostatic effects. At 1× minimal inhibition concentrations, these compounds significantly reduced biofilm formation in all three RGM species to levels between 2.9% and 20.5% relative to controls. Checkerboard assays indicated synergistic interactions between these four compounds and antibiotics such as amikacin, clarithromycin, and linezolid. Of these 12 compound-antibiotic combinations, the pairs of carvacrol-linezolid, carvacrol-amikacin, and gentisaldehyde-clarithromycin demonstrated the most synergy against multiple RGM strains. Moreover, two other compounds citral and geraniol showed synergism with all three test antibiotics. Time-killing assays further confirmed most of synergistic combinations identified in the checkerboard tests. Our research suggests the potential of these essential oils and phenolic aldehydes, both individually and in combination with antibiotics, in treating RGM infections. In addition, this work illuminates applications of these natural compounds in environmental remediation to mitigate bacterial persistence for the control of infectious diseases.
IMPORTANCE
The emergence of antimicrobial resistance within rapidly growing mycobacteria (RGM) poses a significant threat to public health. This study investigates the potential of naturally occurring compounds to combat infections caused by antibiotic-resistant RGM including , , and . We identified four specific natural compounds showing impressive inhibitory effects against antibiotic-resistant clinical strains. These compounds not only inhibited the growth and biofilm formation but also exhibited synergistic interactions with antibiotics against key RGM pathogens. Our findings highlight the alternative treatment strategies for RGM infections and potential environmental applications of these natural compounds in mitigating microbial persistence and controlling infectious diseases.
PubMed: 38934606
DOI: 10.1128/spectrum.00199-24 -
Pharmaceuticals (Basel, Switzerland) May 2024There are more than 170 known species of non-tuberculous mycobacteria, and some are responsible for serious diseases in people infected with them. One of these is Buruli...
There are more than 170 known species of non-tuberculous mycobacteria, and some are responsible for serious diseases in people infected with them. One of these is Buruli ulcers, a neglected tropical disease endemic in more than 33 countries and caused by , which infects skin tissue. Treatment consists of a long-term regimen combining the use of oral rifampin with another anti-tuberculosis drug (e.g., clarithromycin). Patients in these countries face difficulties in accessing and adhering to this therapy. This study investigates the feasibility of formulating stable, optimized clarithromycin as a topical cutaneous cream. The cream was formulated, and its stability was evaluated under different storage temperature conditions and using a stability indicator method. The results showed that the clarithromycin cream was stable for at least 60 days, even at extreme temperatures (40 °C). In conclusion, the data presented here demonstrate the stability of a new form of topical cutaneous clarithromycin, which may offer a new approach to the treatment of Buruli ulcers and clarithromycin-sensitive infections.
PubMed: 38931358
DOI: 10.3390/ph17060691 -
Microorganisms Jun 2024The Esx-1 family proteins of the Type VII secretion systems of and have been assessed and are frequently used as candidates for tuberculosis (TB) diagnosis in both...
The Presence of and and Other Gene Orthologs of the RD 1 Region in Non-Tuberculous Mycobacteria, Mycolicibacteria, Mycobacteroides and Mycolicibacter as Possible Impediments for the Diagnosis of (Animal) Tuberculosis.
The Esx-1 family proteins of the Type VII secretion systems of and have been assessed and are frequently used as candidates for tuberculosis (TB) diagnosis in both humans and animals. The presence of ESAT-6 and CFP 10 proteins, which are the most immunogenic proteins of the Esx-1 system and have been widely investigated for the immunodiagnosis of tuberculosis, in some and in , poses limitations for their use in specific diagnoses of TB. As such, to improve the specificity of the ESAT-6/CFP 10-based cell-mediated immunity (CMI) assays, other proteins encoded by genes within and outside the RD 1 region of the esx-1 locus have been evaluated as candidate antigens for CMI, as well as to investigate humoral responses in combination with ESAT-6 and or CFP 10, with varying specificity and sensitivity results. Hence, in this study, we evaluated various non-tuberculous mycobacteria (NTM), , and species genomes available on the NCBI database for the presence and composition of the RD1 region of the esx-1 locus. In addition, we also assayed by polymerase chain reaction (PCR) and sequencing of available in our culture collection for the presence and sequence diversity of and genes encoding ESAT-6 and CFP 10, respectively. Whole genome sequence (WGS) data analysis revealed the presence of RD 1 gene orthologs in 70 of the over 100 published genomes of pathogenic and non- pathogenic other than tuberculosis. Among species evaluated from our culture collection, in addition to earlier reports of the presence of and in certain , , and sp. N845T were also found to harbour orthologs of both genes. Orthologs of only were detected in , and , whereas in , and , only orthologs were detected. A phylogenetic analysis based on and sequences separated slow-growing from rapidly growing bacteria. These findings strengthen previous suggestions that and may be encoded in the majority of . The role of the Esx-1 system in both pathogenic and non-pathogenic needs further investigation, as these species may pose limitations to immunological assays for TB.
PubMed: 38930534
DOI: 10.3390/microorganisms12061151 -
Antibiotics (Basel, Switzerland) May 2024Slow-growing nontuberculous mycobacteria (NTMs) are highly prevalent and routinely cause opportunistic intracellular infectious disease in immunocompromised hosts.
OBJECTIVES
Slow-growing nontuberculous mycobacteria (NTMs) are highly prevalent and routinely cause opportunistic intracellular infectious disease in immunocompromised hosts.
METHODS
The activity of the triple combination of antibiotics, clarithromycin (CLR), rifabutin (RFB), and clofazimine (CFZ), was evaluated and compared with the activity of single antibiotics as well as with double combinations in an in vitro biofilm assay and an in vivo murine model of subsp. () lung infection.
RESULTS
Treatment of 1-week-old biofilms with the triple combination exerted the strongest effect of all (0.12 ± 0.5 × 10 CFU/mL) in reducing bacterial growth as compared to the untreated (5.20 ± 0.5 × 10/mL) or any other combination (≥0.75 ± 0.6 × 10/mL) by 7 days. The treatment of mice intranasally infected with with either CLR and CFZ or the triple combination provided the greatest reduction in CLR-sensitive bacterial counts in both the lung and spleen compared to any single antibiotic or remaining double combination by 4 weeks posttreatment. After 4 weeks of treatment with the triple combination, there were no resistant colonies detected in mice infected with a CLR-resistant strain. No clear relationships between treatment and spleen or lung organ weights were apparent after triple combination treatment.
CONCLUSIONS
The biofilm assay data and mouse disease model efficacy results support the further investigation of the triple-antibiotic combination.
PubMed: 38927142
DOI: 10.3390/antibiotics13060475 -
Archiv Der Pharmazie Jun 2024Nontuberculous mycobacteria (NTM), which include the Mycobacterium avium complex, are classified as difficult-to-treat pathogens due to their ability to quickly develop...
Nontuberculous mycobacteria (NTM), which include the Mycobacterium avium complex, are classified as difficult-to-treat pathogens due to their ability to quickly develop drug resistance against the most common antibiotics used to treat NTM infections. The overexpression of efflux pumps (EPs) was demonstrated to be a key mechanism of clarithromycin (CLA) resistance in NTM. Therefore, in this work, 24 compounds from an in-house library, characterized by chemical diversity, were tested as potential NTM EP inhibitors (EPIs) against Mycobacterium smegmatis mc155 and M. avium clinical isolates. Based on the acquired results, 12 novel analogs of the best derivatives 1b and 7b were designed and synthesized to improve the NTM EP inhibition activity. Among the second set of compounds, 13b emerged as the most potent NTM EPI. At a concentration of 4 µg/mL, it reduced the CLA minimum inhibitory concentration by 16-fold against the clinical isolate M. avium 2373 overexpressing EPs as primary mechanism of CLA resistance.
PubMed: 38923553
DOI: 10.1002/ardp.202400296 -
Scientific Reports Jun 2024The emergence of drug-resistant Mycobacterium tuberculosis strains is a threat to global health necessitating the discovery of novel chemotherapeutic agents. Natural...
The emergence of drug-resistant Mycobacterium tuberculosis strains is a threat to global health necessitating the discovery of novel chemotherapeutic agents. Natural products drug discovery, which previously led to the discovery of rifamycins, is a valuable approach in this endeavor. Against this backdrop, we set out to investigate the in vitro antimycobacterial properties of medicinal plants from Ghana and South Africa, evaluating 36 extracts and their 252 corresponding solid phase extraction (SPE) generated fractions primarily against the non-pathogenic Mycobacterium smegmatis and Mycobacterium aurum species. The most potent fraction was further evaluated in vitro against infectious M. tuberculosis strain. Crinum asiaticum (bulb) (Amaryllidaceae) emerged as the most potent plant species with specific fractions showing exceptional, near equipotent activity against the non-pathogenic Mycobacterium species (0.39 µg/ml ≤ MIC ≤ 25 µg/ml) with one fraction being moderately active (MIC = 32.6 µg/ml) against M. tuberculosis. Metabolomic analysis led to the identification of eight compounds predicted to be active against M. smegmatis and M. aurum. In conclusion, from our comprehensive study, we generated data which provided an insight into the antimycobacterial properties of Ghanaian and South African plants. Future work will be focused on the isolation and evaluation of the compounds predicted to be active.
Topics: Plants, Medicinal; Microbial Sensitivity Tests; South Africa; Plant Extracts; Ghana; Mycobacterium tuberculosis; Antitubercular Agents; Mycobacterium; Mycobacterium smegmatis; Humans; Anti-Bacterial Agents
PubMed: 38918410
DOI: 10.1038/s41598-024-65369-7 -
International Journal of... Apr 2024Environmental mycobacteria are involved in several infections ranging from lung to skin infections. In Côte d'Ivoire, apart from Mycobacterium ulcerans and...
BACKGROUND
Environmental mycobacteria are involved in several infections ranging from lung to skin infections. In Côte d'Ivoire, apart from Mycobacterium ulcerans and Mycobacterium tuberculosis, little information exists on other species. The culture of these species, a real challenge, especially in developing countries like Cote d'Ivoire, limits their identification. However, there are reports in literature of infections caused by these mycobacteria, and few species have never been described in human or animal infections. These are difficult cases to treat because of their resistance to most antituberculosis antibiotics. The aim of our work was to study the diversity of potentially pathogenic mycobacterial species in wastewater drainage channels in different townships and in two hospital effluents in the city of Abidjan.
METHODS
Wastewater samples were cultured, followed by conventional polymerase chain reaction (PCR) targeting mycobacterial 16S ribonucleic acid (16S RNA) using PA/MSHA primers. 16 S RNA identified were sequenced by Sanger techniques. Sequences obtained were analyzed, and a phylogenic tree was built.
RESULTS
Fast-growing mycobacteria, including Mycobacterium fortuitum, Mycobacterium phocaicum, Mycobacterium sp., and others presence, were confirmed both by culture and molecular techniques. M. fortuitum strain was the same in effluents of the Treichville University Hospital and in the wastewater of the township of Koumassi. New species never isolated in Côte d'Ivoire, such as M. phocaicum, have been identified in wastewater of the township of Yopougon.
CONCLUSION
This study showed that the sewer network in the city of Abidjan is colonized by both potentially pathogenic mycobacteria and saprophytic environmental mycobacteria.
Topics: Cote d'Ivoire; Phylogeny; RNA, Ribosomal, 16S; Humans; Nontuberculous Mycobacteria; Wastewater; Polymerase Chain Reaction; DNA, Bacterial; Mycobacterium
PubMed: 38916386
DOI: 10.4103/ijmy.ijmy_96_24 -
International Journal of... Apr 2024GeneXpert Mycobacterium tuberculosis/rifampicin (MTB/RIF) is a conceptually helpful tool for establishing tuberculosis (TB) disease. Negative results from the GeneXpert...
OBJECTIVE
GeneXpert Mycobacterium tuberculosis/rifampicin (MTB/RIF) is a conceptually helpful tool for establishing tuberculosis (TB) disease. Negative results from the GeneXpert test do not exclude the possibility of diagnosing non-tuberculous mycobacteria lung disease (NTMLD) as a chronic pulmonary disease. When a patient is diagnosed on a clinical basis, and there is no bacteriological evidence of TB, it is necessary to consider NTM as one of the causes of disease with TB-like symptoms. The prevalence of non-tuberculous mycobacteria (NTM) disease is rising globally, but its diagnosis is still delayed and often misdiagnosed as multidrug-resistant TB (MDR-TB). This study highlights the implication of negative GeneXpert MTB/RIF results in suspected TB patients who conducted mycobacteria culture and detected the incidence of NTMLD.
METHODS
In this experimental study, the performance of GeneXpert MTB/RIF-negative results with those of mycobacteria cultures and lung abnormalities among suspected TB patients in a referral hospital in Indonesia were evaluated. From January to August 2022, 100 sputum samples from suspected chronic pulmonary TB patients with GeneXpert MTB/RIF assay-negative results were cultured in Lowenstein-Jensen medium, and the implication among negative GeneXpert result MTB/RIF assay.
RESULTS
7% were confirmed to have MTB and 1% had NTM by culture assay. Moreover, 34% were diagnosed with clinical TB and treated with anti-TB drugs.
CONCLUSION
For patients with negative assay results of GeneXpert MTB/RIF regarding clinically suspected chronic TB infection, further diagnostic tests to determine the causative agents of the lung abnormalities should be carried out.
Topics: Humans; Mycobacterium tuberculosis; Rifampin; Male; Sputum; Female; Adult; Middle Aged; Indonesia; Tuberculosis, Pulmonary; Mycobacterium Infections, Nontuberculous; Tuberculosis, Multidrug-Resistant; Nontuberculous Mycobacteria; Aged; Young Adult
PubMed: 38916385
DOI: 10.4103/ijmy.ijmy_100_24