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Journal of Korean Medical Science May 2024Coinfections with multiple nontuberculous mycobacterial (NTM) species have not been widely studied. We aimed to evaluate the clinical characteristics and treatment...
BACKGROUND
Coinfections with multiple nontuberculous mycobacterial (NTM) species have not been widely studied. We aimed to evaluate the clinical characteristics and treatment outcomes in patients with NTM-pulmonary disease (PD) caused by coinfection with multiple NTM species.
METHODS
We retrospectively reviewed patients with NTM-PD at a tertiary referral hospital in Korea between March 2012 and December 2018. Coinfection was defined as two or more species of NTM pathogens isolated from the same respiratory specimen or different specimens within three months.
RESULTS
Among 1,009 patients with NTM-PD, 147 (14.6%) NTM coinfections were observed (average age 64.7 years, 69.4% women). NTM species were identified more frequently (median 6 vs. 3 times, < 0.001) in the coinfection group than in the single species group, and follow-up duration was also longer in the coinfection group (median 44.9 vs. 27.1 months, < 0.001). complex (MAC) and and (MAB) were the dominant combinations (n = 71, 48.3%). For patients treated for over six months in the MAC plus MAB group (n = 31), sputum culture conversion and microbiological cure were achieved in 67.7% and 41.9% of patients, respectively. We divided the MAC plus MAB coinfection group into three subgroups according to the target mycobacteria; however, no statistical differences were found in the treatment outcomes.
CONCLUSION
In NTM-PD cases, a significant number of multiple NTM species coinfections occurred. Proper identification of all cultured NTM species through follow-up is necessary to detect multispecies coinfections. Further research is needed to understand the nature of NTM-PD in such cases.
Topics: Humans; Female; Male; Middle Aged; Retrospective Studies; Mycobacterium Infections, Nontuberculous; Aged; Coinfection; Nontuberculous Mycobacteria; Treatment Outcome; Lung Diseases; Mycobacterium avium Complex; Anti-Bacterial Agents; Republic of Korea
PubMed: 38804011
DOI: 10.3346/jkms.2024.39.e167 -
Antibiotics (Basel, Switzerland) Apr 2024This study investigates the in vitro activity of α-aroyl--aryl-phenylalanine amides (AAPs), previously identified as antimycobacterial RNA polymerase (RNAP) inhibitors,...
This study investigates the in vitro activity of α-aroyl--aryl-phenylalanine amides (AAPs), previously identified as antimycobacterial RNA polymerase (RNAP) inhibitors, against a panel of 25 non-tuberculous mycobacteria (NTM). The compounds, including the hit compound MMV688845, were selected based on their structural diversity and previously described activity against mycobacteria. Bacterial strains, including the complex, complex, and other clinically relevant NTM, were cultured and subjected to growth inhibition assays. The results demonstrate significant activity against the most common NTM pathogens from the and complexes. Variations in activity were observed against other NTM species, with for instance displaying high susceptibility and and resistance to AAPs. Comparative analysis of RNAP β and β' subunits across mycobacterial species revealed strain-specific polymorphisms, providing insights into differential compound susceptibility. While conservation of target structures was observed, differences in compound activity suggested influences beyond drug-target interactions. This study highlights the potential of AAPs as effective antimycobacterial agents and emphasizes the complex interplay between compound structure, bacterial genetics, and in vitro activity.
PubMed: 38786132
DOI: 10.3390/antibiotics13050404 -
Ethiopian Journal of Health Sciences Sep 2023Non-tuberculous mycobacteria (NTM) have been reported to cause pulmonary and extrapulmonary infections. These NTMs are often misdiagnosed as MTB due to their similar... (Review)
Review
BACKGROUND
Non-tuberculous mycobacteria (NTM) have been reported to cause pulmonary and extrapulmonary infections. These NTMs are often misdiagnosed as MTB due to their similar clinical presentations to tuberculosis, leading to inappropriate treatment and increased morbidity and mortality rates. This literature review aims to provide an overview of the prevalence, clinical manifestations, diagnosis, and management of NTM infections in Africa.
METHODS
A systematic search was performed using various electronic databases including PubMed, Scopus, and Web of Science. The search was limited to studies published in the English language from 2000 to 2021. The following keywords were used: "non-tuberculous mycobacteria", "NTM", "Africa", and "prevalence". Studies that focused solely on the Mycobacterium tuberculosis complex or those that did not report prevalence rates were excluded. Data extraction was performed on eligible studies. Overall, a total of 32 studies met the inclusion criteria and were included in this review.
RESULTS
In our literature review, we identified a total of 32 studies that reported non-tuberculosis mycobacteria (NTM) in Africa. The majority of these studies were conducted in South Africa, followed by Ethiopia and Nigeria. The most commonly isolated NTM species were Mycobacterium avium complex (MAC), Mycobacterium fortuitum, and Mycobacterium abscessus. Many of the studies reported a high prevalence of NTM infections among HIV-positive individuals. Other risk factors for NTM infection included advanced age, chronic lung disease, and previous tuberculosis infection.
CONCLUSION
In conclusion, this literature review highlights the significant burden of non-tuberculosis mycobacteria infections in Africa. The prevalence of these infections is high, and they are often misdiagnosed due to their similarity to tuberculosis. The lack of awareness and diagnostic tools for non-tuberculosis mycobacteria infections in Africa is a major concern that needs to be addressed urgently. It is crucial to improve laboratory capacity and develop appropriate diagnostic algorithms for these infections.
Topics: Humans; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Africa; Prevalence
PubMed: 38784502
DOI: 10.4314/ejhs.v33i5.21 -
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 -
Emerging Infectious Diseases Jun 2024
Topics: Humans; Mycobacterium Infections, Nontuberculous; Nontuberculous Mycobacteria; Virginia; Population Surveillance; Laboratories
PubMed: 38782019
DOI: 10.3201/eid3006.240431 -
Cureus Apr 2024Nontuberculous mycobacteria (NTM) are uncommon causes of cutaneous and musculoskeletal infections. Here, we present an immunocompromised patient with persistent swelling...
Nontuberculous mycobacteria (NTM) are uncommon causes of cutaneous and musculoskeletal infections. Here, we present an immunocompromised patient with persistent swelling in the left hand, wrist, and distal forearm. MRI findings revealed flexor tenosynovitis with synovial hypertrophy of the left hand and wrist and loculated fluid containing rice bodies along the distal flexor digitorum muscles in the volar aspect of the left wrist. The patient underwent flexor tenosynovectomy, and histological examination of the excised tenosynovium and mass revealed noncaseating granulomas. was identified in microbiological cultures. Antimycobacterial therapy was administered postoperatively to manage the infection. This report underscores the significance of maintaining a high index of suspicion for NTM infection when assessing chronic hand swelling, particularly in individuals with compromised immune systems.
PubMed: 38779290
DOI: 10.7759/cureus.58716 -
International Journal of... Jan 2024Microorganisms belonging to the Mycobacterium avium complex (MAC) are ubiquitous in the environment, but only a minority of infected persons develop disease. An...
Microorganisms belonging to the Mycobacterium avium complex (MAC) are ubiquitous in the environment, but only a minority of infected persons develop disease. An underlying lung disease or immune deficiency is a prerequisite for clinical manifestation. However, disseminated MAC disease primarily manifests in people living with human immunodeficiency virus (HIV) in the severe immunodeficiency stage with a whole host of clinical symptoms. We present two cases of disseminated M. avium infection in people living with HIV in the stage of severe immunodeficiency. Both patients exhibited distinct disease progression, with the absence of pulmonary symptoms being a common characteristic. The first patient predominantly experienced high fever, accompanied by diarrhea and severe anemia. The normothermia in the second patient was incongruent with the presence of marked cachexia, severe abdominal pain, and magnetic resonance imaging evidence of abdominal lymph node involvement. The causative agent was isolated from both sputum and stools. The patients underwent treatment that comprised aminoglycoside, macrolide, ethambutol, and rifampicin. Although both patients achieved optimal viral suppression of HIV, the immunologic response to antiretroviral therapy was suboptimal. The first patient died in the setting of severe immunodeficiency due to the development of decompensated liver cirrhosis, while the second patient demonstrated a slight reverse course of the disease.
Topics: Adult; Humans; Male; AIDS-Related Opportunistic Infections; Fatal Outcome; HIV Infections; Mycobacterium avium Complex; Mycobacterium avium-intracellulare Infection; Sputum
PubMed: 38771289
DOI: 10.4103/ijmy.ijmy_23_24 -
International Journal of... Jan 2024Smear microscopy for acid-fast bacilli visualization is important to assess the infectivity rate in patients with pulmonary tuberculosis (PTB), but it has limited... (Comparative Study)
Comparative Study
Correlation of Cyclic Threshold Values Generated by GeneXpert Ultra MTB/RIF and Fluorescence Microscopy to Predict Mycobacterial Burden in Suspected Cases of Pulmonary Tuberculosis.
BACKGROUND
Smear microscopy for acid-fast bacilli visualization is important to assess the infectivity rate in patients with pulmonary tuberculosis (PTB), but it has limited sensitivity; hence, it is important to find an alternative strategy. The aim of our study was to compare the fluorescence microscopy grading by Auramine O phenol staining technique of respiratory samples with the cyclic threshold (Ct) values of GeneXpert Ultra (Mycobacterium tuberculosis/rifampicin [MTB/RIF]) and assess the diagnostic efficacy of GeneXpert Ultra (MTB/RIF) compared to microscopy in suspected cases of PTB.
METHODS
The study was conducted in the Mycobacteriology Laboratory, Department of Microbiology, in Kasturba Hospital, Manipal. The study was a prospective, single-centered, cross-sectional study. Four hundred and fifty-two respiratory samples were included in the study. An optimal Ct cutoff value for ruling smear-positivity and smear-negativity and the mean Ct cutoff value were calculated. Clinical and radiological data from the requisition forms were assessed. IBM SPSS statistics software version 22 was used. The correlation between GeneXpert Ultra (MTB/RIF) Ct values and smear status was calculated by polychoric correlation. The extended McNemar's test was used to find the association between the variables.
RESULTS
GeneXpert Ultra (MTB/RIF) yielded a higher positivity rate of 22.2% compared to smear microscopy 17.2%. Ct value and smear grading yielded a positive correlation (P = 0.8681; P < 0.05). GeneXpert Ultra (MTB/RIF) yielded nontuberculous mycobacteria in five undetected cases and speciated as Mycobacterium abscessus complex.
CONCLUSIONS
Our study confirms the GeneXpert Ultra (MTB/RIF) Ct value levels as a predictor of smear positivity.
Topics: Humans; Tuberculosis, Pulmonary; Mycobacterium tuberculosis; Cross-Sectional Studies; Prospective Studies; Microscopy, Fluorescence; Male; Female; Adult; Middle Aged; Sputum; Young Adult; Rifampin; Aged; Sensitivity and Specificity; Adolescent; Bacterial Load
PubMed: 38771279
DOI: 10.4103/ijmy.ijmy_199_23 -
International Journal of... Jan 2024In patients with cystic fibrosis (CF), representatives of the fast-growing Mycobacterium abscessus complex (MABSc) are often distinguished, but the culture of the...
BACKGROUND
In patients with cystic fibrosis (CF), representatives of the fast-growing Mycobacterium abscessus complex (MABSc) are often distinguished, but the culture of the material taken from such patients increases the growth time. We analyzed the terms of cultivation of MABSc representatives on dense nutrient media and also evaluated the productivity of a modified nutrient medium based on agar for the isolation of Burkholderia cepacia complex (BCC).
METHODS
Sixty-four strains of MABSc isolated from patients with CF and suspected tuberculosis were analyzed. The material from the patients was cultured on a universal chromogenic medium, 5% blood agar, yolk-salt agar, selective medium for isolation of BCC, and Löwenstein-Jensen medium. The cultures were incubated for 5 days (37°C, aerobic conditions), after for 23 days (28°C, aerobic conditions). The productivity of the developed nutrient medium was evaluated by the number of cells that gave visible growth after culturing 0.1 mL of a bacterial suspension of 103 CFU/mL.
RESULTS
76.8% of the strains grew in a 2-week period, and 23.2% of the strains were obtained at a later date from 18 to 28 days (average: 21.23 days). The modified medium with a concentration of 240 mg of iron (III) polymaltose hydroxide proved to be the most optimal for the isolation of MABSc.
CONCLUSION
When using a chromogenic medium for culture material from patients with CF, it is necessary to extend incubation up to 28 days to increase the probability of MABSc isolation. The modified BCC medium showed a good selectivity result but required further investigation.
Topics: Humans; Cystic Fibrosis; Culture Media; Mycobacterium abscessus; Mycobacterium Infections, Nontuberculous; Time Factors; Bacteriological Techniques; Burkholderia cepacia complex
PubMed: 38771277
DOI: 10.4103/ijmy.ijmy_205_23 -
MBio May 2024Nontuberculous mycobacteria (NTM) are environmentally ubiquitous organisms that predominately cause NTM pulmonary disease (NTMPD) in individuals over the age of 65. The...
UNLABELLED
Nontuberculous mycobacteria (NTM) are environmentally ubiquitous organisms that predominately cause NTM pulmonary disease (NTMPD) in individuals over the age of 65. The incidence of NTMPD has increased in the U.S., exceeding that of . However, the mechanisms leading to higher susceptibility and severity of NTMPD with aging are poorly defined in part due to the lack of animal models that accurately recapitulate human disease. Here, we compared bacterial load, microbial communities, and host responses longitudinally between three young (two female and one male) and two aged (two female) rhesus macaques inoculated with subsp. (MAH) in the right caudal lobe. Unilateral infection resulted in a low bacterial load in both young and aged animals confined to the infected side. Although a robust inflammatory response was only observed in the inoculated lung, immune cell infiltration and antigen-specific T cells were detected in both lungs. Computed tomography, gross pathology, and histopathology revealed increased disease severity and persistence of bacterial DNA in aged animals. Additional analyses showed the translocation of gut and oral-pharyngeal bacterial DNA into the lower respiratory microbiome. Finally, single-cell RNA sequencing revealed a heightened inflammatory response to MAH infection by alveolar macrophages in aged animals. These data are consistent with the model that increased disease severity in the aged is mediated by a dysregulated macrophage response that may be sustained through persistent antigen presence.
IMPORTANCE
Nontuberculous mycobacteria (NTM) are emerging as pathogens of high consequence, as cases of NTM pulmonary disease (NTMPD) have exceeded those of . NTMPD can be debilitating, particularly in patients over 65 years of age, as it causes chronic cough and fatigue requiring prolonged treatments with antibiotics. The underlying mechanisms of this increased disease severity with age are poorly understood, hampering the development of therapeutics and vaccines. Here, we use a rhesus macaque model to investigate the impact of age on host-NTM interactions. This work shows that aging is associated with increased disease severity and bacterial persistence in aged rhesus macaques, thus providing a preclinical model to develop and test novel therapeutics and interventions.
PubMed: 38771046
DOI: 10.1128/mbio.00829-24