Nontuberculous Mycobacteria Research Articles

GenoMycAnalyzer: a web-based tool for species and drug resistance prediction for Mycobacterium genomes

BackgroundDrug-resistant tuberculosis (TB) is a major threat to global public health. Whole-genome sequencing (WGS) is a useful tool for species identification and drug resistance prediction, and many clinical laboratories are transitioning to WGS as a routine diagnostic tool. However, user-friendly and high-confidence automated bioinformatics tools are needed to rapidly identify M. tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM), detect drug resistance, and further guide treatment options.ResultsWe developed GenoMycAnalyzer, a web-based software that integrates functions for identifying MTBC and NTM species, lineage and spoligotype prediction, variant calling, annotation, drug-resistance determination, and data visualization. The accuracy of GenoMycAnalyzer for genotypic drug susceptibility testing (gDST) was evaluated using 5,473 MTBC isolates that underwent phenotypic DST (pDST). The GenoMycAnalyzer database was built to predict the gDST for 15 antituberculosis drugs using the World Health Organization mutational catalogue. Compared to pDST, the sensitivity of drug susceptibilities by the GenoMycAnalyzer for first-line drugs ranged from 95.9% for rifampicin (95% CI 94.8–96.7%) to 79.6% for pyrazinamide (95% CI 76.9–82.2%), whereas those for second-line drugs ranged from 98.2% for levofloxacin (95% CI 90.1–100.0%) to 74.9% for capreomycin (95% CI 69.3–80.0%). Notably, the integration of large deletions of the four resistance-conferring genes increased gDST sensitivity. The specificity of drug susceptibilities by the GenoMycAnalyzer ranged from 98.7% for amikacin (95% CI 97.8–99.3%) to 79.5% for ethionamide (95% CI 76.4–82.3%). The incorporated Kraken2 software identified 1,284 mycobacterial species with an accuracy of 98.8%. GenoMycAnalyzer also perfectly predicted lineages for 1,935 MTBC and spoligotypes for 54 MTBC.ConclusionsGenoMycAnalyzer offers both web-based and graphical user interfaces, which can help biologists with limited access to high-performance computing systems or limited bioinformatics skills. By streamlining the interpretation of WGS data, the GenoMycAnalyzer has the potential to significantly impact TB management and contribute to global efforts to combat this infectious disease. GenoMycAnalyzer is available at http://www.mycochase.org.

The changing epidemiology of pulmonary infection in children and adolescents with cystic fibrosis: an 18-year experience.

The impact of evolving treatment regimens, airway clearance strategies, and antibiotic combinations on the incidence and prevalence of respiratory infection in cystic fibrosis (CF) in children and adolescents remains unclear. The incidence, prevalence, and prescription trends from 2002 to 2019 with 18,339 airway samples were analysed. Staphylococcus aureus [-3.86% (95% CI -5.28-2.43)] showed the largest annual decline in incidence, followed by Haemophilus influenzae [-3.46% (95% CI -4.95-1.96)] and Pseudomonas aeruginosa [-2.80%95% CI (-4.26-1.34)]. Non-tuberculous mycobacteria and Burkholderia cepacia showed a non-significant increase in incidence. A similar pattern of change in prevalence was observed. No change in trend was observed in infants < 2years of age. The mean age of the first isolation of S. aureus (p < 0.001), P. aeruginosa (p < 0.001), H. influenza (p < 0.001), Serratia marcescens (p = 0.006) and Aspergillus fumigatus (p = 0.02) have increased. Nebulised amikacin (+ 3.09 ± 2.24 prescription/year, p = 0.003) and colistin (+ 1.95 ± 0.3 prescriptions/year, p = 0.032) were increasingly prescribed, while tobramycin (-8.46 ± 4.7 prescriptions/year, p < 0.001) showed a decrease in prescription. Dornase alfa and hypertonic saline nebulisation prescription increased by 16.74 ± 4.1 prescriptions/year and 24 ± 4.6 prescriptions/year (p < 0.001). There is a shift in CF among respiratory pathogens and prescriptions which reflects the evolution of cystic fibrosis treatment strategies over time.

Patients at risk of nontuberculous mycobacterial pulmonary disease who need testing evaluated using a modified Delphi process by European experts

BackgroundIdentifying patients at risk of nontuberculous mycobacterial pulmonary disease (NTM-PD) is challenging. Delays in NTM-PD identification and management are associated with declining lung function and increased morbidity and mortality.Study design and methodsEuropean NTM-PD experts (n=12) participated in a three-round modified Delphi process to score symptoms and comorbidities potentially associated with NTM-PD as reasons to test for nontuberculous mycobacteria.ResultsExperts reached a consensus on the symptoms and comorbidities that should and should not prompt testing for nontuberculous mycobacteria. Requirements for testing were scored as high (mean ≥7), medium (mean ≥4–&lt;7) or low (mean &lt;4). Nontuberculous mycobacteria testing should be undertaken when multiple suggestive symptoms are present simultaneously in all patients except those with cancer (7.3–8.8), or when radiology is indicative of NTM-PD (≥8.9). Symptoms of persistent sputum production, recurrent respiratory infection and haemoptysis should prompt testing for nontuberculous mycobacteria, particularly in those with underlying respiratory diseases. Symptomatic patients with bronchiectasis or previous tuberculosis/NTM-PD or those being prescribed or undergoing long-term macrolide therapy for a respiratory condition should also be tested. Testing is not warranted in patients without an underlying respiratory disorder or in those without a history of respiratory disorders unless presenting with multiple symptoms.ConclusionsAssessing patients’ risk of NTM-PD is challenging. This Delphi consensus process provides insight into symptoms and clinical characteristics that should prompt NTM-PD assessment. Timely testing and diagnosis would enable initiation of appropriate management.

Multiparameter immunoprofiling for the diagnosis and differentiation of progressive versus nonprogressive nontuberculous mycobacterial lung disease-A pilot study.

Clinical prediction of nontuberculous mycobacteria lung disease (NTM-LD) progression remains challenging. We aimed to evaluate antigen-specific immunoprofiling utilizing flow cytometry (FC) of activation-induced markers (AIM) and IFN-γ enzyme-linked immune absorbent spot assay (ELISpot) accurately identifies patients with NTM-LD, and differentiate those with progressive from nonprogressive NTM-LD. A Prospective, single-center, and laboratory technician-blinded pilot study was conducted to evaluate the FC and ELISpot based immunoprofiling in patients with NTM-LD (n = 18) and controls (n = 22). Among 18 NTM-LD patients, 10 NTM-LD patients were classified into nonprogressive, and 8 as progressive NTM-LD based on clinical and radiological features. Peripheral blood mononuclear cells were collected from patients with NTM-LD and control subjects with negative QuantiFERON results. After stimulation with purified protein derivative (PPD), mycobacteria-specific peptide pools (MTB300, RD1-peptides), and control antigens, we performed IFN-γ ELISpot and FC AIM assays to access their diagnostic accuracies by receiver operating curve (ROC) analysis across study groups. Patients with NTM-LD had significantly higher percentage of CD4+/CD8+ T-cells co-expressing CD25+CD134+ in response to PPD stimulation, differentiating between NTM-LD and controls. Among patients with NTM-LD, there was a significant difference in CD25+CD134+ co-expression in MTB300-stimulated CD8+ T-cells (p <0.05; AUC-ROC = 0.831; Sensitivity = 75% [95% CI: 34.9-96.8]; Specificity = 90% [95% CI: 55.5-99.7]) between progressors and nonprogressors. Significant differences in the ratios of antigen-specific IFN-γ ELISpot responses were also seen for RD1-nil/PPD-nil and RD1-nil/anti-CD3-nil between patients with nonprogressive vs. progressive NTM-LD. Our results suggest that multiparameter immunoprofiling can accurately identify patients with NTM-LD and may identify patients at risk of disease progression. A larger longitudinal study is needed to further evaluate this novel immunoprofiling approach.

Mycobacterium abscessus subsp. Bolletti-associated osteomyelitis of the lumbar vertebrae in immunocompetent patient

Introduction: Nontuberculous mycobacteria (NTM)-related Vertebral Osteomyelitis (VO) is a rare disease with challenging diagnosis and management. NTM-caused disease more often develops in vulnerable populations, affecting individuals who are immunocompromised or who have underlying health conditions. Methods: We report a case of Mycobacterium abscessus subsp. Bolletti-associated VO in a 60-year-old immunocompetent female patient. Results: The patient presented with chronic back pain and paresis of the legs. She underwent surgery - partial resection of L4 and L5 vertebral bodies, and vertebroplasty with allograft. Culture for Mycobacterium abscessus subspace Bolletti was positive from operation material, and treatment with multiagent antibacterial therapy was started. After 2 months of treatment, an asymptomatic m.psoas abscess was identified on control imaging. Repeated surgery with abscess drainage was applied, and treatment of M.abscessus infection was continued. After a 12-month course of treatment, the patient recovered successfully and could walk without support. During treatment, she experienced a lot of drug side effects including peripheral neuropathy. Conclusion: Sampling for Mycobacterium tuberculosis and NTM should be always considered in both, immunocompromised and immunocompetent patients presenting with clinical symptoms and imaging findings consistent with VO.

Retrospective and prospective evaluation of the FluoroType®-Mycobacteria VER 1.0 assay for the identification of mycobacteria from cultures in a French center.

Rapid, reliable identification of mycobacteria from positive cultures is essential for patient management, particularly for the differential diagnosis of Mycobacterium tuberculosis complex (MTBC) and nontuberculous mycobacteria (NTM) species. The aim of the present study was to evaluate a new "In-Vitro-Diagnostic"-certified PCR kit, FluoroType®-Mycobacteria VER1.0 (Hain Lifescience GmbH) for NTM and MTBC identification from cultures. Mycobacteria identification isolated from positive cultures during routine practice at the Lyon university hospital mycobacteria laboratory obtained by hsp65 amplification/sequencing were compared retrospectively and prospectively to those obtained by and the FluoroType®-Mycobacteria VER1.0kit. The overall agreement between hsp65 amplification/sequencing and the FluoroType®-Mycobacteria VER1.0kit was 88.4% (84/95); 91.2% (52/57) for the retrospective period and 84.2% (32/38) for the prospective period. There were 9 (9.5%) minor discrepancies (species in the FluoroType®-Mycobacteria VER1.0database and identified at genus level): 4 during the retrospective period, 5 during the prospective period; and 2 (2.1%) major discrepancies (species in the FluoroType®-Mycobacteria VER1.0database and identified incorrectly to species level): 1 during the retrospective period (M. kumamotonense identified as M. abscessus subsp massiliense by the kit) and 1 during the prospective period (M. chimaera identified as M. smegmatis by the kit). Including concordant results at genus level and minor discrepancies, 17.9% (17/95) of strains were identified as Mycobacterium sp. by the FluoroType®-Mycobacteria-VER1.0kit. The good performance of the FluoroType®-Mycobacteria-VER1.0kit with few major discrepancies could enable its use for first-line identification of positive mycobacteria cultures. However, an alternative identification method at least for reference laboratories is needed owing to the non-negligible proportion of NTM strains were identified at genus level.

Genomic epidemiology of Mycobacterium abscessus at an adult cystic fibrosis programme reveals low potential for healthcare-associated transmission.

Nontuberculous mycobacteria (NTM) has been reported to be transmitted between people with cystic fibrosis (CF) attending CF centres. A suspected Mycobacterium abscessus outbreak was investigated at the University of Texas Southwestern (UTSW) Adult CF Program using a combination of pathogen genomic sequencing and epidemiologic methods. The objectives of the present study were to apply the Healthcare-Associated Links in Transmission of NTM (HALT NTM) study to investigate the occurrence of potential healthcare-associated transmission and/or acquisition of NTM among people with CF infected with genetically similar NTM isolates. Whole-genome sequencing of respiratory M. abscessus isolates from 50 people with CF receiving care at UTSW was performed to identify genetically similar isolates. Epidemiologic investigation, comparison of respiratory and environmental isolates, and home residence watershed mapping were studied. Whole-genome sequencing analysis demonstrated seven clusters of genetically similar M. abscessus (four ssp. abscessus and three ssp. massiliense). Epidemiologic investigation revealed potential opportunities for healthcare-associated transmission within three of these clusters. Healthcare environmental sampling did not recover M. abscessus, but did recover four human disease-causing species of NTM. No subjects having clustered infections lived in the same home residence watershed. Some subjects were infected with more than one M. abscessus genotype, both within and outside of the dominant circulating clones. Healthcare-associated person-to-person transmission of M. abscessus appears to be rare at this centre. However, polyclonal infections of M. abscessus species and subspecies, not originating from the endemic hospital environment, suggest multiple shared modes of acquisition outside the healthcare setting.

Biofilm prevention concentration of clarithromycin against clinically relevant species of nontuberculous mycobacteria.

Mycobacterium avium complex (MAC) and Mycobacterium abscessus are a group of nontuberculous mycobacteria (NTM) that have been described as human pathogens. Their ability to develop biofilms in tissues and medical devices is one of the most important pathogenicity factors, with important implications in diagnosis and treatment. Macrolides are usually considered one of the bases of this treatment. Here we have studied the biofilm prevention concentration (BPC) of 16 strains (n=16) with clarithromycin to avoid the biofilm development by these NTM. In this study, all M. abscessus strains have similar BPC, while MAC strains showed different values. For MAC the concentrations ranged between 1-16 mg/L, while for M. abscessus the concentration was 32 mg/L for all strains except one that was 64 mg/L. These results open the possibility of using macrolides for the prevention of biofilm development in patients with a risk of developing NTM disease.

The Price of Beauty: A Literature Review on Non-Tuberculous Mycobacteria Infection After Cosmetic Procedures.

Abstract Non-tuberculous mycobacteria (NTM) infection of the skin and soft tissues is a complication of cosmetic procedures. The incidence of cutaneous NTM infections has increased significantly as aesthetic operations have become more commonplace. With the rise of cosmetic tourism, the geographic expansion of NTM infections is a major concern. Due to the unique pathogenesis of NTM infections, diagnosis and treatment remain significant challenges for clinicians. Clinical management relies on a combination of antibiotic therapy with drug susceptibility testing and appropriate surgical debridement. Some new drugs, photodynamic therapy, and bacteriophage therapy have been developed in recent years, and may improve the aesthetic outcomes. This review summarizes the cosmetic procedures prone to NTM infections in recent years and their clinical features. We propose a 2-stage treatment procedure, including a hospitalization phase and a follow-up phase. We aim to increase the alertness of clinicians to NTM infections for timely detection and treatment. Level of Evidence: 3

Gradenigo Syndrome With Facial and Hypoglossal Nerve Impairment Caused by Nontuberculous Mycobacteria Successfully Treated by Antibiotics Without Surgery.

Gradenigo Syndrome With Facial and Hypoglossal Nerve Impairment Caused by Nontuberculous Mycobacteria Successfully Treated by Antibiotics Without Surgery.

Diagnosing adult and pediatric extrapulmonary tuberculosis by MPT64 antigen detection with immunohistochemistry and immunocytochemistry using reproduced polyclonal antibodies.

Diagnosing extrapulmonary tuberculosis (EPTB) is challenging. Immunohistochemistry or immunocytochemistry has been used to diagnose tuberculosis (TB) by detection of MPT64 antigen from various extrapulmonary specimens and has shown good diagnostic performance in our previous studies. The test can distinguish between disease caused by Mycobacterium tuberculosis (Mtb) complex and nontuberculous mycobacteria and can be applied on formalin-fixed paraffin-embedded tissue. As the antibodies previously used were in limited supply, a new batch of polyclonal antibodies was developed for scale-up and evaluated for the first time in this study. Our aim was to assess the diagnostic accuracy of the MPT64 test with reproduced antibodies in the high burden settings of Pakistan and India. Patients were enrolled prospectively. Samples from suspected sites of infection were collected and subjected to histopathologic and/or cytologic evaluation, routine TB diagnostics, GeneXpert MTB/RIF (Xpert), and the MPT64 antigen detection test. Patients were followed until the end of treatment. Based on a composite reference standard (CRS), 556 patients were categorized as TB cases and 175 as non-TB cases. The MPT64 test performed well on biopsies with a sensitivity and specificity of 94% and 75%, respectively, against a CRS. For cytology samples, the sensitivity was low (36%), whereas the specificity was 81%. Overall, the MPT64 test showed higher sensitivity (73%) than Xpert (38%) and Mtb culture (33%). The test performed equally well in adults and children. We found an additive diagnostic value of the MPT64 test in conjunction with histology and molecular tests, increasing the yield for EPTB. In conclusion, immunochemical staining with MPT64 antibodies improves the diagnosis of EPTB in high burden settings and could be a valuable addition to routine diagnostics.

Rapid and accurate identification and differentiation of Mycobacterium tuberculosis and non-tuberculous mycobacteria using PCR kits available in a high-burden setting.

Infections caused by mycobacteria, including Mycobacterium tuberculosis complex (MTBC) and non-tuberculous mycobacteria (NTM), are a major public health issue worldwide. An accurate diagnosis of mycobacterial species is a challenge for surveillance and treatment, particularly in high-burden settings usually associated with low- and middle-income countries. In this study, we analyzed the clinical performance of two commercial PCR kits designed for the identification and differentiation of MTBC and NTM, available in a high-burden setting such as Ecuador. A total of 109 mycobacteria isolates were included in the study, 59 of which were previously characterized as M. tuberculosis and the other 59 as NTM. Both kits displayed great clinical performance for the identification of M. tuberculosis, with 100% sensitivity. On the other hand, for NTM, one of the kits displayed a good clinical performance with a sensitivity of 94.9% (CI 95%: 89-100%), while the second kit had a reduced sensitivity of 77.1% (CI 95%: 65-89%). In conclusion, one of the kits is a fast and reliable tool for the identification and discrimination of MTBC and NTM from clinical isolates.

Complete genome sequences and multidrug resistance genotypes of nontuberculous mycobacteria isolates from the Central Tuberculosis Reference Laboratory Muhimbili Tanzania

Background: Nontuberculous mycobacteria (NTM) usually comprise a group of environmental bacteria, with emerging but elusive coinfection with tuberculous mycobacteria, causing pulmonary tuberculosis. Whole genome sequencing may give insight into potential antimicrobial resistance genotypes, giving clinicians and policymakers proper directions in clinical applications and management regimens. Methods: WGS was performed on twenty-four gDNA isolates from archival samples at the Central Tuberculosis Reference Laboratory using the MinION Oxford Nanopore Sequencing approach. Out of twenty-four, two were confirmed to belong to the NTM group. Further analysis was done to resolve the complete genomes of two nontuberculous mycobacteria strains isolated from tuberculosis patients. We then combined phylogenomics, reference-based scaffolding and average nucleotide identity (ANI) analysis to delineate each strain's taxonomic position and corresponding features. Results: Our findings reveal that the two strains fit into the genus Mycolicibacterium, and the closest relative is Mycolicibacterium novocastrense. Coupling BacAnt and CARD-based antibiotic resistance analyses revealed multidrug-resistant genotypes of diverse spectra and mechanisms. While the BC02 strain is genetically resistant to beta-lactams, macrolides and rifamycins, the BC05 strain portrays an extended drug resistance genotype encompassing beta-lactams, macrolides, polyamines, and aminoglycosides. Both strains possess a single nucleotide polymorphism (SNP) of the RNA polymerase beta-subunit (rpoB), representing resistance to the first-line rifampicin. Additionally, the BC05 strain genetically portrays resistance to ethambutol, isoniazid and fosfomycin through mechanisms involving target alteration through SNPs, drug inactivation and efflux. Conclusion: Our findings strongly suggest the potential implication of multidrug-resistant NTM clinical isolates in the pathogenesis of pulmonary tuberculosis.

Efficacy of SPR720 in murine models of non-tuberculous mycobacterial pulmonary infection.

Non-tuberculous mycobacterial pulmonary disease (NTM-PD) is increasing worldwide, with Mycobacterium avium complex (MAC) and Mycobacterium abscessus as the predominant pathogens. Current treatments are poorly tolerated and modestly effective, highlighting the need for new treatments. SPR719, the active moiety of the benzimidazole prodrug SPR720, inhibits the ATPase subunits of DNA gyrase B, a target not exploited by current antibiotics, and therefore, no cross-resistance is expected with standard-of-care (SOC) agents. To evaluate the in vitro activity of SPR719 against MAC and M. abscessus clinical isolates, including those resistant to SOC agents, and in vivo efficacy of SPR720 in murine non-tuberculous mycobacteria (NTM) pulmonary infection models. NTM isolates were tested for susceptibility to SPR719. Chronic C3HeB/FeJ and severe combined immunodeficient murine models of pulmonary infection were used to assess efficacy of SPR720 against MAC and M. abscessus, respectively. SPR719 was active against MAC (MIC90, 2 mg/L) and M. abscessus (MIC90, 4 mg/L) clinical isolates. Efficacy of SPR720 was demonstrated against MAC pulmonary infection, both as a monotherapy and in combination with SOC agents. SPR720 monotherapy exhibited dose-dependent reduction in bacterial burden, with the largest reduction observed when combined with clarithromycin and ethambutol. Efficacy of SPR720 was also demonstrated against M. abscessus pulmonary infection where monotherapy exhibited a dose-dependent reduction in bacterial burden with further reductions detected when combined with SOC agents. In vitro activity of SPR720 against common NTM pathogens and efficacy in murine infections warrant the continued clinical evaluation of SPR720 as a new oral option for the treatment of NTM-PD.

Implication of Negative GeneXpert Mycobacterium tuberculosis/Rifampicin Results in Suspected Tuberculosis Patients: A Research Study.

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. 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. 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. 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.

Bovine Tuberculosis in Wild Boar (Sus scrofa) in Slovenia.

Mycobacteria of the Mycobacterium tuberculosis complex (MTC) are capable of infecting a wide variety of animals. Wild boar (Sus scrofa) has been recognized as an important wildlife reservoir for bovine tuberculosis. We screened wild boar in Slovenia for the presence of (1) Mycobacterium bovis in tissues and (2) antibodies to M. bovis in blood samples. In 2016 and 2017, 1284 tissue samples from 676 wild boar were subjected to cultivation. In 2018 and 2019, blood samples from 132 wild boar were examined using an ELISA kit. None of the MTC species were isolated from the tissue samples, and no antibodies to M. bovis were detected in the blood samples. Several nontuberculous mycobacteria (NTM), identified by 16S rRNA sequencing and/or matrix-assisted laser desorption ionization time-of-flight mass spectrometry, were found in the tissues of 9.8% of the wild boar: Mycobacterium nonchromogenicum, Mycobacterium peregrinum/Mycobacterium septicum, Mycobacterium avium, Mycobacterium engbaekii, Mycobacterium arupense, Mycobacterium algericum, Mycobacterium bohemicum, Mycobacterium confluentis, Mycobacterium flavescens, Mycobacterium fortuitum, Mycobacterium thermoresistibile, and Mycobacterium vaccae. Species-level identification was not possible for 21.2% of the isolates. At the time of the study, wild boar in Slovenia were not at risk from bTB; the significance of the presence of NTM in wild boar remains to be clarified and evaluated from a One Health perspective.

Adjuvant surgical resection for nontuberculous mycobacterial pulmonary disease: Effectiveness and complications.

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. 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. 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, P = 0.004), male sex (OR = 0.251, 95% CI: 0.071-0.892, P = 0.033), and extensive NTMPD lesions involving three lobes or more (OR = 5.362, 95% CI: 1.315-21.857, P = 0.019). Interstitial lung disease (OR = 13.111, 95% CI: 1.554-110.585, P = 0.018) and pneumonectomy (OR = 19.667, 95% CI: 2.017-191.797, P = 0.018) were statistically significant risk factors for postoperative mortality. 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.

Tuberculosis and Nontuberculous Mycobacterial Infections in Patients with Spondyloarthritis: A Population-Based Study.

Background and Objectives: Tuberculosis is caused by Mycobacterium tuberculosis (MTB), while nontuberculous mycobacteria (NTM) encompass a group of mycobacterial species that are distinct from the MTB complex and leprae. Spondyloarthritis (SpA) is a group of chronic inflammatory diseases with shared clinical characteristics and is treated with biological agents; however, their use may elevate the risk of MTB and NTM infections. This study aimed to compare the incidence and risk of MTB and NTM infections in patients with SpA, including ankylosing spondylitis (AS) and psoriatic arthritis (PsA), using a population-based approach. Materials and Methods: This study included 2333 patients with SpA and 9332 age- and sex-matched controls from the Korea National Health Insurance Service-National Sample Cohort database from 2002 to 2019. The patients were identified using the International Classification of Diseases-10 codes for AS, PsA, MTB, and NTM. Results: The results showed that a negligible percentage of patients with SpA developed NTM (0.002%) and MTB (0.016%), with no significant difference in the incidence rate ratio (IRR) compared to controls. Among patients with SpA treated with biologics, the IRRs for NTM and MTB were 5.66 and 3.069, respectively; however, these were not statistically significant. No cases of NTM or MTB infection were reported in female patients with SpA treated with biologics. In both the SpA patient group and the control group, the incidence of MTB was higher in individuals over 60 years old compared to those under 60 years old. Cox proportional hazard analysis revealed a significant adjusted hazard ratio of 1.479 for MTB in patients with SpA after adjusting for age, sex, smoking history, insurance level, and comorbidities. However, this significance was not maintained when biological therapy was further adjusted. Conclusions: Our study indicated that the risks of NTM and MTB infection are not elevated in patients with SpA. Although biological use may potentially increase the risk of MTB infection, it does not lead to a significant increase in incidence rates. Proactive screening for latent tuberculosis and adequate prophylaxis using biologics can effectively manage the risk of NTM and MTB infections.

Building size and disinfectant type influence the detection and concentration of Mycobacterium spp. in hot water plumbing

The number of nontuberculous mycobacteria (NTM) lung disease cases is increasing in the United States (US). This respiratory disease is primarily caused by three NTM species: Mycobacterium avium, M. intracellulare, and M. abscessus. Since disease transmission could occur through water aerosolization, this study investigated these three species' occurrence (sporadic and persistent) in hot water samples collected from residences (n = 70) and office buildings (n = 30) across the US. A longitudinal survey design was used. Three quantitative Polymerase Chain Reaction (qPCR) assays were used to measure the mycobacterial species in the water samples. Additionally, the water's disinfectant residual was measured. A structure's age and square footage were evaluated to predict mycobacterial contamination. Also, the seasonal occurrence of each species was assessed by structure type. Residences had a 43 % (30/70), and office buildings had a 77 % (23/30) detection frequency of one or more Mycobacterium spp. in their hot water. The age of the structure influenced M. intracellulare detection frequency but not M. avium and M. abscessus. The structure's square footage affected M. avium and M. intracellulare detection frequency but not M. abscessus. In chlorinated water, M. intracellulare was detected 1.4× more often in office buildings' hot water than in chloraminated water. In chloraminated water, the Mycobacterium spp. were detected 2–2.5× more often in residences, while M. avium and M. abscessus were detected 1.5–2.3× more often in office buildings, compared to chlorinated water. Each Mycobacterium spp. had a different trend associated with the type of structure and disinfectant. Further research is needed to better understand NTM occurrence in the built environment to improve public health.

Misdiagnosis of non-tuberculous mycobacteria as tuberculous by the GeneXpert MTB/RIF Ultra: Fact or fiction?

No abstract available.