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Ethiopian Journal of Health Sciences Sep 2023Non-tuberculous mycobacteria (NTMs) are ubiquitous, free-living, environmental saprophytic microorganisms. NTMs belong to the genus Mycobacterium which includes...
BACKGROUND
Non-tuberculous mycobacteria (NTMs) are ubiquitous, free-living, environmental saprophytic microorganisms. NTMs belong to the genus Mycobacterium which includes Mycobacterium tuberculosis (MTB). NTMs have lately been a major cause of pulmonary disease (PD) in immuno-compromised individuals including HIV-1 patients. NTMs and MTB appear similar based on microscopy, radiology, and clinical symptoms; consequently, this may lead to misdiagnosis. This study sought to establish the prevalence of NTM pulmonary disease in HIV-1 patients presumed to have pulmonary tuberculosis.
METHODS
A cross-sectional analytical laboratory study design was used targeting 617 adult HIV-1 infected patients presenting with presumptive pulmonary TB at Bungoma County Hospital Comprehensive Care Clinic in Western Kenya between July 2021 to June 2022.
RESULTS
A total of 75 (12.2%, 4.6 -9.8 CI) of the participants presented with presumptive MTB and had TB-like symptoms while 542 (87.8%, 12.5 -30.7 CI) were negative. Additionally, 56 (9.1%) were infected with NTMs. HIV-positive participants had a significantly higher prevalence of NTMs 62 (11.8%, 5.6 -9.2 CI) compared to 2 (2.1%, 0.4 -1.8 CI). In HIV + study participants P<0.0001. M. avium was the most prevalent NTM, 25(33.3%), followed by M. fortuitum 20 (26.7%). A significant number of the isolates were M. tuberculosis 10 (13.3%) as well as M. kansasii 8 (10.7%).
CONCLUSION
There seems to be a high prevalence of NTMPD in HIV-1 patients which is assumed to be pulmonary TB. Differential diagnosis of the mycobacterium species is necessary to help improve disease management and outcomes in this group of patients.
Topics: Humans; Kenya; Male; Adult; Female; Mycobacterium Infections, Nontuberculous; Cross-Sectional Studies; Prevalence; Tuberculosis, Pulmonary; HIV Infections; Middle Aged; Nontuberculous Mycobacteria; HIV-1; Young Adult
PubMed: 38784500
DOI: 10.4314/ejhs.v33i5.3 -
Annals of Laboratory Medicine Jan 2024Limited data are available regarding the activity of SPR719, a derivative of benzimidazole, against diverse nontuberculous mycobacteria (NTM) species. We investigated...
Limited data are available regarding the activity of SPR719, a derivative of benzimidazole, against diverse nontuberculous mycobacteria (NTM) species. We investigated the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of SPR719 against clinical NTM isolates, including clarithromycin- and amikacin-resistant strains. NTM isolates were obtained from patients with NTM-pulmonary disease caused by various NTM species, including complex, (subspecies and ), , and . Regardless of clarithromycin or amikacin resistance, the MIC and MBC values of SPR719 were comparable among these major pathogenic NTM species. In over 70% of the isolates, the MIC values were ≤2 μg/mL with MBC values of ≤4 μg/mL. The MIC and MBC values of were relatively lower than those of the other species with little difference between them, demonstrating the bactericidal properties of SPR719. The activity of SPR719 against major clinical NTM species suggests that SPR719 can serve as a novel treatment option for NTM-pulmonary disease.
Topics: Humans; Clarithromycin; Amikacin; Nontuberculous Mycobacteria; Benzimidazoles; Anti-Bacterial Agents; Mycobacterium Infections, Nontuberculous
PubMed: 37665290
DOI: 10.3343/alm.2024.44.1.92 -
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 -
ACG Case Reports Journal Jul 2023is associated with skin and soft-tissue infections, yet isolated liver involvement is rare. A 67-year-old asymptomatic man was referred for endoscopic ultrasound (EUS)...
is associated with skin and soft-tissue infections, yet isolated liver involvement is rare. A 67-year-old asymptomatic man was referred for endoscopic ultrasound (EUS) to evaluate a gastric lesion and an incidental liver mass. EUS revealed a heterogeneous liver mass that was sampled. Pathology revealed necrotic granulomatous inflammation and positive acid-fast bacilli stain with deoxyribonucleic acid. Levofloxacin plus trimethoprim and sulfamethoxazole for 3 months were used for complete resolution of liver lesion. Isolated nontuberculous liver involvement is uncommon. We report the first case of a liver mass caused by diagnosed by EUS-fine needle aspiration.
PubMed: 37426570
DOI: 10.14309/crj.0000000000001083 -
Medicine Dec 2023Injection-related abscesses are a common complication in clinical practice, but the identification of infected bacteria might be difficult.
RATIONALE
Injection-related abscesses are a common complication in clinical practice, but the identification of infected bacteria might be difficult.
PATIENT CONCERNS
A 51-year-old female patient was admitted to the hospital due to a lump on her right buttock that emerged after receiving intramuscular injections to treat left shoulder joint pain. The lump gradually enlarged into a 3.0 to 4.5 cm mass at the time of admission with symptoms such as skin redness, itching, and pain.
DIAGNOSES
The patient received ultrasonic and other laboratory examinations. Laboratory results from the drainage indicated that the infection was caused by a rapidly growing mycobacteria and was confirmed as Mycobacterium fortuitum by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry.
INTERVENTIONS
The patient was treated with antibiotics for 12 days after incision and drainage of the abscess in the right buttock. Local dressings were changed regularly. A migration lesion that appeared 3 days after treatment was drained and cleaned when it matured.
OUTCOMES
The lesion substantially decreased in size and the patient was discharged after 2 months of treatment.
LESSONS
Rapidly growing mycobacteria are rare but important pathogens that should be considered in patients with injection-related abscesses. Early identification and appropriate treatment can result in a favorable prognosis.
Topics: Humans; Female; Middle Aged; Mycobacterium fortuitum; Abscess; Mycobacterium Infections; Mycobacterium; Muscles; Pain; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 38050215
DOI: 10.1097/MD.0000000000036060 -
BMC Microbiology Mar 2024Cameroon is a tuberculosis (TB) burden country with a 12% positivity among TB presumptive cases. Of the presumptive cases with a negative TB test, some are infected with...
BACKGROUND
Cameroon is a tuberculosis (TB) burden country with a 12% positivity among TB presumptive cases. Of the presumptive cases with a negative TB test, some are infected with Non-tuberculous Mycobacteria (NTM). However, the diagnosis of NTM infections remains difficult due to the lack of tools in many laboratories, particularly in resource limited laboratories and remote setting. The present study was undertaken to determine NTM profile and associated comorbidities among TB presumptive people.
METHODS
A retrospective study was conducted from December 2018 to December 2019 in the Tuberculosis-National Reference Laboratory (TB-NRL) for Bacteriological analysis of samples and Jamot Hospital of Yaounde (JHY) for clinical evaluation of confirmed NTM patients. We included in this study data of 5267 TB presumptive people previously diagnosed using three consecutive samples and having culture and SD Bioline results with or without Microscopy and reverse hybridization-based Line Probe Assay(LPA) results. The data on co-morbidities or history of people infected with NTM were then collected from the three participants with available clinical data.
RESULTS
We collected data of 5267 presumptive TB people. Among them, 3436 (65.24%), have a positive culture with 3200 (60.75%) isolates belong to Mycobacterium tuberculosis Complex (MBTC) and 236 (4.48%) to NTM. Our results showed that, 123 (52.11%) NTM were isolated from people with negative microscopy and 113 (47.88%) from people with positive microscopy. Among the 236 NTM, 108 (45.8%) isolates were identified using LPA. M. fortuitum was the most represented species (32.41%) followed by M. intracellulare (19.44%). Sputum had the highest proportion of NTM (56%), followed by bronchial aspirations (31%). The extra-pulmonary samples presented lower proportions of isolates compared to pulmonary samples. Some patients affected with NTM presented comorbidities as HIV infection, Pulmonary tuberculosis, Type 2 diabetes, Chronic bronchitis and Alveolar pneumonia.
CONCLUSIONS
Our study showed the presence of NTM strains among presumptive TB people with a predominance of M. fortuitum and M. intracellulare. It is important to implement a surveillance system of NTM in TB burden country and also to develop a point-of-care test for NTM identification in limited-resource settings.
Topics: Humans; Nontuberculous Mycobacteria; HIV Infections; Mycobacterium Infections, Nontuberculous; Retrospective Studies; Diabetes Mellitus, Type 2; Cameroon; Tuberculosis
PubMed: 38532357
DOI: 10.1186/s12866-024-03256-x -
BioRxiv : the Preprint Server For... Feb 2024Endolysins are highly evolved bacteriophage-encoded lytic enzymes produced to damage the bacterial cell wall for phage progeny release. They offer promising potential as...
Endolysins are highly evolved bacteriophage-encoded lytic enzymes produced to damage the bacterial cell wall for phage progeny release. They offer promising potential as highly specific lytic proteins with a low chance of bacterial resistance. The diversity in lysin sequences and domain organization can be staggering. analysis of bacteriophage and prophage genomes can help identify endolysins exhibiting unique features and high antibacterial activity, hence feeding the pipeline of narrow-spectrum protein antibiotics. Mycobacteriophage lysis cassettes mostly have two lytic enzymes, LysinA and LysinB. The enzyme LysinA targets peptidoglycan in the cell wall and possesses a modular architecture. LysinB typically contains a single domain and acts upon the mycolyl ester linkages in mycolyl-arabinogalactan-peptidoglycan (Payne et al., 2010). This study aimed to find novel LysinBs against . After a detailed characterization of lysis cassettes from three prophages, we chose to work on a LysinB (hereafter described as LysinB_MF) found in an incomplete prophage (phiE1336, 9.4 kb in strain E1336). LysinB_MF showed low sequence similarity with any other endolysins in the database and formed a separate clade on phylogenetic analysis. LysinB_MF's structure, extracted from the AlphaFold Protein Structure Database, demonstrated a modular architecture with two structurally distinct domains: a peptidoglycan-binding domain (PGBD) at the N-terminal and the characteristic alpha/beta hydrolase domain connected via a linker peptide. We found the alpha/beta hydrolase domain, which is the enzyme-active domain (EAD), contains the conserved Ser-Asp-His catalytic triad with a tunnel-like topology and forms intermolecular hydrogen bonds. The PGBD shows structural similarity to the cell-wall binding domain of an amidase from , hinting at its acquisition due to domain mobility. Our electrostatic potential analysis suggested that PGBD might be essential to the enzyme activity. This was experimentally validated by generating a truncated version of the enzyme, which demonstrated about six-fold decreased activity compared to its native form. The antimycobacterial activity of this enzyme was also compromised in its absence. Based on our analysis, PGBD emerged as an integral constituent of enzymes with diverse functional properties and is predicted to be a conserved cross-kingdom. Overall, this study highlights the importance of mining mycobacterial prophages as a novel endolysin source. It also provides unique insights into the diverse architecture of mycobacteriophage-encoded endolysins and the importance of functional domains for their catalytic activities.
PubMed: 38405724
DOI: 10.1101/2024.02.15.580446 -
International Journal of Molecular... Mar 2024C19 steroids and C22 steroids are vital intermediates for the synthesis of steroid drugs. Compared with C19 steroids, C22 steroids are more suitable for synthesizing...
C19 steroids and C22 steroids are vital intermediates for the synthesis of steroid drugs. Compared with C19 steroids, C22 steroids are more suitable for synthesizing progesterone and adrenocortical hormones, albeit less developed. 9,22-dihydroxy-23,24-bisnorchol-4-ene-3-one(9-OHBA), due to its substituents at positions C-9 and C-22, is a beneficial and innovative steroid derivative for synthesizing corticosteroids. We focused on the C22 pathway in ATCC 35855, aiming to develop a productive strain that produces 9-OHBA. We used a mutant strain, MFΔ, that knocked out from ATCC 35855 named MFKD in this study as the original strain. Hsd4A and FadA5 are key enzymes in controlling the C19 metabolic pathway of steroids in ATCC 35855. After knocking out , MFKDΔ accumulated 81.47% 9-OHBA compared with 4.13% 9-OHBA in the strain MFKD. The double mutant MFKDΔΔ further improved the selectivity of 9-OHBA to 95.13%, and 9α-hydroxy-4-androstenedione (9-OHAD) decreased to 0.90% from 4.19%. In the end, we obtained 6.81 g/L 9-OHBA from 10 g/L phytosterols with a molar yield of 80.33%, which showed the best performance compared with formerly reported strains.
Topics: Mycobacterium fortuitum; Androstenedione; Molar; Phytosterols; Progesterone
PubMed: 38612391
DOI: 10.3390/ijms25073579 -
Southern African Journal of Infectious... 2024Non-tuberculous mycobacteria (NTM) management comprises prolonged therapy that includes macrolides. Non-tuberculous mycobacteria can cause disease in patients with...
BACKGROUND
Non-tuberculous mycobacteria (NTM) management comprises prolonged therapy that includes macrolides. Non-tuberculous mycobacteria can cause disease in patients with predisposing conditions such as HIV and structural lung disease. Local data on NTM disease and macrolide resistance are scarce, and routine antimicrobial susceptibility testing is currently not performed for NTM in South Africa.
OBJECTIVES
This study aims to characterise NTM isolated at Tshepong National Health Laboratory Service (NHLS) according to species and antimicrobial susceptibility pattern.
METHOD
A retrospective data analysis of NTM isolates from Tshepong NHLS was performed from January to June 2020. GenoType NTM-DR was performed on selected isolates where the assay can confirm the species and determine resistance to macrolides and aminoglycosides.
RESULTS
Of the 194 collected NTM isolates, 183 were included in the study. Patients' ages ranged from 1 day to 81 years (median 36 years). The most common specimen was sputum (84.7%), followed by gastric aspirate (6.6%). The most common NTM isolated were (67.6%), (12.6%), (4.3%), (3.9%), and (3.9%). Macrolide resistance occurred in 2.8% of tested isolates; no aminoglycoside resistance was detected. Although most isolates were from males (62.3%), resistance was observed only in females.
CONCLUSION
predominated, with only two and two isolates showing macrolide resistance; aminoglycoside resistance was absent.
CONTRIBUTION
This study highlights the need for increased awareness of NTM, regular nationwide NTM surveillance, and monitoring of resistance trends to guide future patient management and ensure good treatment outcomes.
PubMed: 38322299
DOI: 10.4102/sajid.v39i1.525 -
Infection & Chemotherapy Mar 2024The distribution of species and characteristics of non
- tuberculous mycobacteria (NTM) differ, and surveillance data for changes in antimicrobial...BACKGROUND
The distribution of species and characteristics of non
- tuberculous mycobacteria (NTM) differ, and surveillance data for changes in antimicrobial susceptibilities of NTM is insufficient. This study analyzed the changes in antimicrobial susceptibility trends across NTM species and assessed the appropriateness of empirical antimicrobial drugs for NTM.MATERIALS AND METHODS
We retrospectively analyzed the clinical characteristics, including demographics, distribution of NTM species, antimicrobial drug susceptibilities, and outcomes, at a teaching hospital in Jeju Island from 2009 - 2022.
RESULTS
Overall, 342 patients were included in the analysis; 93.0% were classified into the pulmonary group (PG) and 7.0% into the extrapulmonary group (EPG). The isolation rate of was significantly higher in PG (36.8% 0%, = 0.001), while that of was significantly higher in EPG (4.5% 31.3%, = 0.001). The antimicrobial susceptibility rate is higher against clarithromycin (89.9%) and amikacin (83.3%) and lower against rifampin (54.7%) and ethambutol (28.1%). The susceptibility rate to clarithromycin was over 80%, but those to rifampin and ethambutol showed decreasing annual trends. Of the 162 patients who received empirical antimicrobial therapy, actual antimicrobial susceptibility rates were high (90.1%) using empirical macrolide, and relatively low using ethambutol and rifampin (28.0% and 58.8%, respectively).
CONCLUSION
This is the first study of analysis of the distribution, baseline characteristics, and antimicrobial susceptibility of isolated NTM species in pulmonary and extrapulmonary patients in Jeju Island over 10 years. Policies that continuously monitor changes in susceptibility rate are required to ensure effective treatment strategies.
PubMed: 37674341
DOI: 10.3947/ic.2023.0052