Project description:The diagnosis of pulmonary non-tuberculous mycobacterial disease (pNTM) is dependent on the isolation of NTM in culture, which is prone to overgrowth and contamination and may not capture the diversity of mycobacteria present, including rare or unidentified species. This study aimed to develop a culture independent method of detecting and identifying mycobacteria from sputum samples using partial sequencing of the hsp65 gene. DNA was extracted from sputum samples from subjects with pNTM and disease controls. Multiplexed partial sequencing of the hsp65 gene was performed using the Illumina MiSeq and custom primers. A reference database of hsp65 sequences was created for taxonomy assignment. Sequencing results were obtained from 42 subjects (31 cases, 11 controls). Mycobacterial sequences were identified in all subjects. In 90.5% of samples more than one species was found (median 5.5). The species isolated in culture was detected by sequencing in 81% of subjects and was the most abundant species in 62%. The sequencing of NTM from clinical samples reveals a far greater diversity than conventional culture and suggests NTM are present as communities rather than a single species. NTM were found to be present even in the absence of isolation in culture or clinical disease.
Project description:Nontuberculous mycobacteria (NTM) are environmental organisms associated with pulmonary disease without person-to-person transmission. Although genetic causes of disseminated NTM infection are well characterized, genetic causes for most human susceptibility to pulmonary NTM infection have not been determined.Family histories for relevant disease characteristics were obtained as part of an ongoing natural history study. Six families were identified in which at least two blood relatives had pulmonary NTM. A systematic review of medical records extracted data relevant to pulmonary infection and baseline demographics. Data were reconfirmed by telephone interviews.Familial clustering of pulmonary NTM was proven in six families. Four of the families were white, and the majority of affected individuals were women. The average age at diagnosis was 56.4 +/- 10.7 years, the average height was 167.5 +/- 8.7 cm, and the mean BMI was 22.0 +/- 2.98 kg/m(2). Scoliosis was present in 31%. Five of 12 patients had cystic fibrosis transmembrane conductance regulator gene variations, but none had classic cystic fibrosis. Infections were caused by both slow and rapid growing mycobacteria, including Mycobacterium avium, Mycobacterium intracellulare, Mycobacterium kansasii, Mycobacterium abscessus, and Mycobacterium massiliense. Family members were typically infected with different species of NTM.We identified six familial clusters of pulmonary NTM infection, suggesting that there are genetic factors contributing to host susceptibility to pulmonary infection with NTM among some individuals with nodular bronchiectatic disease.
Project description:A uniform prognostic marker is needed for nontuberculous mycobacterial pulmonary disease (NTM-PD) due to the diverse clinical course. We aimed to seek the utility of the BACES score, originally derived to predict all-cause mortality, for various outcomes. To calculate the BACES score, one point was given for each of the following factors: body mass index < 18.5 kg/m2, age ≥ 65 years, presence of cavities, elevated erythrocyte sedimentation rate, or male sex. The study included 681 patients, of whom 97 (14.2%), 189 (27.7%), 192 (28.2%), 143 (21.0%), 47 (6.9%), and 13 (1.9%) had BACES scores of 0 to 5. Those with greater BACES scores were more likely to experience dyspnea, body weight loss, and anorexia. With severe disease, the risk of disease progression increased while the rate of treatment culture conversion decreased. After adjustment of comorbidities, higher BACES score was independently associated with the risk of mortality from respiratory causes or infection. As a simple and efficient bedside tool for assessing the severity of NTM-PD, the BACES score has the potential to be utilized as a surrogate marker for uniform severity assessment.
Project description:The clinical relevance of newly described nontuberculous mycobacteria is often unclear. We report a case of pulmonary infection caused by Mycobacterium hassiacum in an immunocompetent patient in Austria who had chronic obstructive pulmonary disease. Antimicrobial drug susceptibility testing showed low MICs for macrolides, aminoglycosides, fluoroquinolones, tetracyclines, imipenem, and linezolid.
Project description:RationaleThe clinical features of patients infected with pulmonary nontuberculous mycobacteria (PNTM) are well described, but the genetic components of infection susceptibility are not.ObjectivesTo examine genetic variants in patients with PNTM, their unaffected family members, and a control group.MethodsWhole-exome sequencing was done on 69 white patients with PNTM and 18 of their white unaffected family members. We performed a candidate gene analysis using immune, cystic fibrosis transmembrance conductance regulator (CFTR), cilia, and connective tissue gene sets. The numbers of patients, family members, and control subjects with variants in each category were compared, as was the average number of variants per person.Measurements and main resultsA significantly higher number of patients with PNTM than the other subjects had low-frequency, protein-affecting variants in immune, CFTR, cilia, and connective tissue categories (35, 26, 90, and 90%, respectively). Patients with PNTM also had significantly more cilia and connective tissue variants per person than did control subjects (2.47 and 2.55 compared with 1.38 and 1.40, respectively; P = 1.4 × 10(-6) and P = 2.7 × 10(-8), respectively). Patients with PNTM had an average of 5.26 variants across all categories (1.98 in control subjects; P = 2.8 × 10(-17)), and they were more likely than control subjects to have variants in multiple categories. We observed similar results for family members without PNTM infection, with the exception of the immune category.ConclusionsPatients with PNTM have more low-frequency, protein-affecting variants in immune, CFTR, cilia, and connective tissue genes than their unaffected family members and control subjects. We propose that PNTM infection is a multigenic disease in which combinations of variants across gene categories, plus environmental exposures, increase susceptibility to the infection.
Project description:ObjectiveThe aim of this study was to compare long-term mortality following diagnosis of pulmonary nontuberculous mycobacterial (NTM) disease between patients with and without rheumatoid arthritis (RA) and to evaluate predictive factors for death outcomes.MethodsWe reviewed the electronic medical records of all patients who were newly diagnosed with pulmonary NTM disease at participating institutions between August 2009 and December 2018. Patients were followed until death, loss to follow-up, or the end of the study. Taking into consideration the presence of competing risks, we used the cumulative incidence function with Gray's test and Fine-Gray regression analysis for survival analysis.ResultsA total of 225 patients (34 RA patients and 191 non-RA controls) were followed, with a mean time of 47.5 months. Death occurred in 35.3% of RA patients and 25.7% of non-RA patients. An exacerbation of pulmonary NTM disease represented the major cause of death. The estimated cumulative incidence of all-cause death at 5 years was 24% for RA patients and 23% for non-RA patients. For NTM-related death, the 5-year cumulative incidence rate was estimated to be 11% for RA patients and 18% for non-RA patients. Gray's test revealed that long-term mortality estimates were not significantly different between patient groups. Fine-Gray regression analysis showed that the predictive factors for NTM-related death were advanced age (adjusted hazards ratio 7.28 [95% confidence interval 2.91-18.20] for ≥80 years and 3.68 [1.46-9.26] for 70-80 years vs. <70 years), male sex (2.40 [1.29-4.45]), Mycobacterium abscessus complex (4.30 [1.46-12.69] vs. M. avium), and cavitary disease (4.08 [1.70-9.80]).ConclusionsRA patients with pulmonary NTM disease were not at greater risk of long-term mortality compared with non-RA patients. Rather, advanced age, male sex, causative NTM species, and cavitary NTM disease should be considered when predicting the outcomes of RA patients with pulmonary NTM disease.
Project description:BackgroundOwing to the unsatisfactory results of antibiotic treatment alone, surgical resection is currently considered as adjunctive therapy in patients with nontuberculous mycobacterial pulmonary disease (NTM-PD). However, reports regarding the outcomes of surgery vary considerably by institution. Here, we investigated the surgical outcomes and risk factors associated with unfavorable outcomes after surgery.MethodsWe analyzed patients with NTM-PD who underwent pulmonary resection at Seoul National University Hospital between January 1, 2006, and December 31, 2020, and assessed the types of surgical procedures, complications, and long-term outcomes. Multivariate logistic regression analysis was used to identify the risk factors associated with treatment refractoriness or recurrence after surgery.ResultsAmong 67 patients who underwent surgery during the study period, the most common indication for surgery was persistent culture positivity despite rigorous medical treatment (80.6%), followed by longstanding cavitary lesions or radiographic aggravation (10.4%) and massive hemoptysis (4.5%). Among 53 patients with positive mycobacterial cultures at the time of surgery, 38 (71.7%) achieved initial negative culture conversion, 9 (17.0%) of whom experienced recurrence. Nine (13.4%) patients experienced postoperative complications, which were managed without lasting morbidity and mortality. Female sex (adjusted odds ratio [aOR] 6.63; 95% confidence interval [CI] 1.04-42.4; P = .046), preoperative positive mycobacterial culture (aOR 5.87; 95 %CI 1.04-33.08; P = .045), and residual lesions (aOR 6.86; 95 %CI 1.49-31.56; P = .013) were associated with refractoriness or recurrence.ConclusionsPulmonary resection is a reasonable treatment modality for patients with refractory NTM-PD or major complications such as massive hemoptysis. The potential risk factors associated with unfavorable outcomes included female sex, preoperative positive mycobacterial culture, and residual lesions after surgery.
Project description:BackgroundSince nontuberculous mycobacterial pulmonary disease (NTM-PD) is common in middle-aged/elderly slender women at risk of osteoporosis, we hypothesized that NTM-PD could be associated with osteoporosis. The study aimed to evaluate the prevalence of osteoporosis in patients with NTM-PD compared with that in the general population and determine the factors associated with osteoporosis in the subjects, including the serum estradiol (E2) and 25-hydroxyvitamin D (25OHD) levels.MethodsWe have recruited 228 consecutive adult patients with NTM-PD from a prospective cohort study at the Keio University Hospital, who had no history of osteoporosis or osteoporosis-associated bone fracture but underwent dual-energy X-ray absorptiometry-based bone mineral density (BMD) evaluation from August 2017-September 2019. The E2 and 25OHD levels were measured in 165 patients with available stored serum samples. We performed multivariable logistic regression analyses for osteopenia and osteoporosis.ResultsOsteoporosis (T-score ≤ - 2.5) and osteopenia (T-score - 1 to - 2.5) were diagnosed in 35.1% and 36.8% of patients with NTM-PD, respectively. Compared with the general population, the proportion of osteoporosis was significantly higher in 50-59-, 60-69-, and 70-79-year-old women with NTM-PD. Multivariable analysis revealed that older age (adjusted odds ratio [aOR] for 1-year increase = 1.12; 95% confidence interval [CI] = 1.07-1.18), female sex (aOR = 36.3; 95% CI = 7.57-174), lower BMI (aOR for 1 kg/m2 decrease = 1.37; 95% CI = 1.14-1.65), and chronic Pseudomonas aeruginosa (PA) infection (aOR = 6.70; 95% CI = 1.07-41.8) were independently associated with osteoporosis. Additionally, multivariable analysis in 165 patients whose serum E2 and 25OHD levels were measured showed that both low E2 levels (< 10 pg/mL) and lower 25OHD levels were independently associated with osteoporosis.ConclusionsMiddle-aged/elderly women with NTM-PD have a higher prevalence of osteoporosis than the general population. BMD screening should be considered in NTM-PD, especially in older females with severe diseases such as chronic PA infection and lower BMI, and low serum E2 and 25OHD levels.
Project description:Patients with nontuberculous mycobacterial lung disease (NTM-LD) have increased mortality. The impact of NTM species on the risk of mortality remains unclear, especially that of death by non-cancer causes. We conducted a retrospective cohort study from 2006 to 2018 in a tertiary-care hospital in Taiwan. We enrolled patients who fulfilled the microbiological diagnostic criteria of NTM-LD. The mortality causes within 8 years after diagnosis were identified, and the Cox proportional hazard regression was performed for risk factors of mortality. A total of 1,652 subjects with NTM-LD were included. Among them, 723 (43.8%) were infected by Mycobacterium avium complex (MAC), 408 (24.7%) by M. abscessus complex (MABC), 120 (7.3%) by Mycobacterium kansasii (MK), 304 (18.4%) by other rapid-growing mycobacteria (RGM), and 97 (5.9%) by other slow-growing mycobacteria (SGM) groups. The 8-year all-cause mortality was 45.2% for all and the highest in the MK-LD group (59.2%), followed by the MABC-LD and MAC-LD groups. The adjusted hazard ratios were 2.20 (95% confidence interval: 1.40-3.46) in the MK-LD, 1.85 (1.54-2.22) in the MABC-LD, and 1.65 (1.12-2.41) in the MAC-LD groups for all-cause mortality, compared with the SGM group. Kaplan-Meier survival curves showed that all-cause mortality, non-cancer mortality, and mortality due to chronic airway diseases were significantly correlated with NTM species (log-rank p = 0.0031, < 0.001, and 0.001, respectively). High 8-year mortality rates were found in patients with NTM-LDs according to different NTM species. Notably, the difference was significant in non-cancer mortality causes, especially in chronic airway diseases.