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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 -
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 Jun 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.
Topics: Mycobacterium Infections, Nontuberculous; Lung; Macaca mulatta; Animals; Male; Female; Age Factors; Tomography, X-Ray Computed; Transcriptome; Microbiota
PubMed: 38771046
DOI: 10.1128/mbio.00829-24 -
Journal of Investigative Medicine High... 2024The association between Hairy Cell Leukemia (HCL) and non-tuberculous mycobacterial infections (NTMs) is well described, most notably . The exact pathophysiology is not... (Review)
Review
The association between Hairy Cell Leukemia (HCL) and non-tuberculous mycobacterial infections (NTMs) is well described, most notably . The exact pathophysiology is not known. We report a case of a 31-year-old male with concomitantly diagnosed HCL and disseminated infection who presented with rash, pancytopenia, and bulky axillary lymphadenopathy. The was initially diagnosed through use of cell-free DNA detection and confirmed by bone marrow and lymph node cultures. Hairy Cell Leukemia was diagnosed with peripheral flow cytometry and confirmed via the same bone marrow sample. His HCL was put into remission with a single course of cladribine and rituximab chemotherapy; however, his infection persisted for 6 months despite aggressive antimicrobial and surgical therapy. It was finally controlled using high-dose rifampin in combination with azithromycin and ethambutol. This case highlights the known link between HCL and Furthermore, it hints at potential causes beyond chemotherapy-induced immunocompromise. Notable possibilities include HCL cells acting as sanctuary sites for to evade the immune system, and subclinical infections causing NLRP3 inflammasome overactivation to trigger the oncogenic transformation to HCL. More research into the pathophysiologic link between HCL and infections would allow for more effective prevention, diagnosis, and treatment of these severe atypical infections which are the major cause of morbidity in the cladribine era of HCL treatment.
Topics: Humans; Male; Leukemia, Hairy Cell; Adult; Mycobacterium Infections, Nontuberculous; Mycobacterium kansasii; Cladribine; Rifampin; Azithromycin; Rituximab
PubMed: 38767131
DOI: 10.1177/23247096241253343 -
Annals of Thoracic Medicine 2024Standard antibiotic treatment for nontuberculous mycobacteria pulmonary disease (NTMPD) has unsatisfactory success rates. Pulmonary resection is considered adjunctive...
BACKGROUND
Standard antibiotic treatment for nontuberculous mycobacteria pulmonary disease (NTMPD) has unsatisfactory success rates. Pulmonary resection is considered adjunctive therapy for patients with refractory disease or severe complications, but surgical indications and extent of resection remain unclear. We present surgical treatment outcomes for NTMPD and analyzes risk factors for unfavorable outcomes.
METHODS
We conducted a retrospective investigation of medical records for patients diagnosed with NTMPD who underwent surgical treatment at Asan Medical Center between 2007 and 2021. We analyzed clinical data including microbiological and surgical outcomes.
RESULTS
A total of 71 NTMPD patients underwent thoracic surgery. Negative conversion of acid-fast bacillus (AFB) culture following pulmonary resection was observed in 51 (73.9%) patients. In terms of long-term outcomes, negative conversion was sustained in 38 cases (55.1%). Mortality occurred in 7 patients who underwent pulmonary resections for NTMPD. Statistically significant associations with factors for recurrence or non-negative conversion of AFB culture were found in older age (odds ratio [OR] =1.093, 95% confidence interval [CI]: 1.029-1.161, = 0.004), male sex (OR = 0.251, 95% CI: 0.071-0.892, = 0.033), and extensive NTMPD lesions involving three lobes or more (OR = 5.362, 95% CI: 1.315-21.857, = 0.019). Interstitial lung disease (OR = 13.111, 95% CI: 1.554-110.585, = 0.018) and pneumonectomy (OR = 19.667, 95% CI: 2.017-191.797, = 0.018) were statistically significant risk factors for postoperative mortality.
CONCLUSION
Pulmonary resection can be an effective adjuvant treatment option for NTMPD patients, with post-operative antibiotic treatment as the primary treatment. Careful patient selection is crucial, considering the associated risk factors and resectability due to complications and recurrence.
PubMed: 38766373
DOI: 10.4103/atm.atm_237_23 -
ACS Environmental Au May 2024Nontuberculous mycobacteria (NTM) are any mycobacteria that do not cause tuberculosis or leprosy. While the majority of NTM are harmless and some of them are considered... (Review)
Review
Toward Characterizing Environmental Sources of Non-tuberculous Mycobacteria (NTM) at the Species Level: A Tutorial Review of NTM Phylogeny and Phylogenetic Classification.
Nontuberculous mycobacteria (NTM) are any mycobacteria that do not cause tuberculosis or leprosy. While the majority of NTM are harmless and some of them are considered probiotic, a growing number of people are being diagnosed with NTM infections. Therefore, their detection in the environment is of interest to clinicians, environmental microbiologists, and water quality researchers alike. This review provides a tutorial on the foundational approaches for taxonomic classifications, with a focus on the phylogenetic relationships among NTM revealed by the 16S rRNA gene, gene, and gene, and by genome-based approaches. Recent updates on the genus taxonomy are also provided. A synthesis on the habitats of 189 mycobacterial species in a genome-based taxonomy framework was performed, with attention paid to environmental sources (e.g., drinking water, aquatic environments, and soil). The 16S rRNA gene-based classification accuracy for various regions was evaluated (V3, V3-V4, V3-V5, V4, V4-V5, and V1-V9), revealing overall excellent genus-level classification (up to 100% accuracy) yet only modest performance (up to 63.5% accuracy) at the species level. Future research quantifying NTM species in water systems, determining the effects of water treatment and plumbing conditions on their variations, developing high throughput species-level characterization tools for use in the environment, and incorporating the characterization of functions in a phylogenetic framework will likely fill critical knowledge gaps. We believe this tutorial will be useful for researchers new to the field of molecular or genome-based taxonomic profiling of environmental microbiomes. Experts may also find this review useful in terms of the selected key findings of the past 30 years, recent updates on phylogenomic analyses, as well as a synthesis of the ecology of NTM in a phylogenetic framework.
PubMed: 38765059
DOI: 10.1021/acsenvironau.3c00074