Treatment outcome definitions in nontuberculous mycobacterial pulmonary disease: an NTM-NET consensus statement

Relationship between culture conversion and clinical outcomes in nontuberculous mycobacterial pulmonary disease: Narrative review

PURPOSE

Nontuberculous mycobacterial pulmonary disease (NTMPD) is a chronic, often progressive condition associated with a significant symptom burden and increased mortality. Goals of NTMPD treatment include microbiological eradication, symptom reduction, improved quality of life (QoL), and preventing disease progression. Antibiotics are used to reduce microbial burden, and cultures of sputum are used to guide treatment. However, it is unclear whether achieving culture-negative status (often called "culture conversion") is associated with improved clinical outcomes. Studies use a variety of measures including symptom burden, radiological status, lung function, 6-min walk test distance, QoL assessments, and mortality to evaluate clinical outcomes related to changes in how patients feel, function, and survive. There is strong interest in more clearly understanding which clinical benefits may be associated with culture conversion. As NTMPD can cause sustained structural lung damage and declines in long-term pulmonary function, it is important to have clear evidence if prevention of these morbidities is associated with culture conversion.

METHODS

This targeted literature review summarizes the published evidence regarding associations between sputum culture conversion and clinical outcomes in patients with NTMPD. Identified studies used varying definitions of culture conversion and treatment success, making interpretation of outcomes across studies challenging.

RESULTS

Although some studies suggest an association between culture conversion and aspects of clinical improvement, overall, there are currently few high-quality studies supporting a link.

CONCLUSION

Further clarification of the relationship between culture conversion and clinical outcomes would be helpful in improving clinical monitoring and therapeutic decision-making during the treatment of patients with NTMPD.

Aminoglycoside susceptibility and treatment outcomes in Mycobacterium avium complex pulmonary disease

BACKGROUND

Treatment with parenteral aminoglycosides is recommended for patients with advanced Mycobacterium avium complex pulmonary disease (MAC-PD). However, the evidence supporting susceptibility-based treatment with aminoglycosides is limited.

METHODS

We retrospectively reviewed patients with MAC-PD treated with aminoglycosides for at least eight weeks between October 2005 and December 2018 at a tertiary referral center in South Korea. Patients without drug susceptibility test (DST) results were excluded.

RESULTS

Among 951 patients diagnosed with MAC-PD, 46 received at least six months of treatment, including aminoglycosides. Thirty patients with DST results were enrolled in this study. The median age was 57 years (interquartile range [IQR], 50-62 years), with 70 % female. Four patients had received prior treatment for MAC-PD. M. intracellulare was the most common causative species (46.7 %), followed by M. avium (43.3 %). The median duration of follow-up was 41.3 months (IQR 7.6-68.7 months) after treatment initiation. Sputum acid-fast bacilli smear was positive in 43.3 %; cavities were present in 73.3 % of patients. The median treatment duration was 16.4 months (IQR 13.5-27.0 months). Culture conversion and all-cause mortality rates were 60.0 % and 20.0 %, respectively. Amikacin was susceptible in 80.0 % of the patients; however, culture conversion rates did not differ based on susceptibility. Amikacin-susceptible patients had a higher, but insignificant, odds of culture conversion (odds ratio 1.667, 95 % confidence interval 0.275-10.094, p = 0.578) CONCLUSION: Our findings suggest that DST is not correlated with efficacy of aminoglycosides in MAC-PD. Further research is required to clarify its role in treatment decisions.

Malignant Pleural Mesothelioma: From Pathophysiology to Innovative Actionable Targets

BACKGROUND

Pleural mesothelioma (PM) is a rare and highly aggressive cancer which arises from mesothelial layer and primarily linked to asbestos exposure, genetic predispositions, and specific mutations. Despite current treatment modalities, including chemotherapy, antiangiogenic therapy and more recently immunotherapy, the prognosis remains dismal, with a median survival time of 6-18 months.

OBJECTIVES

The urgent need for novel therapeutic strategies has prompted research into molecular targets and precision medicine approaches. At present, many potential targets for therapeutic strategies have been identified, and emerging clinical trials are demonstrating certain clinical efficacy.

METHODS

This review examines advancements in understanding PM's genetic and epigenetic landscape, signaling pathways, and promising therapeutic targets.

RESULTS

We also discuss the results of recent clinical trials and their potential implications for future treatment paradigms.

The therapeutic impact of maximum chemotherapy possession days during three consecutive months in non-tuberculous mycobacterial lung disease: A real-world experience

PURPOSE

Adherence to guideline recommendations in the treatment of non-tuberculous mycobacterial lung disease (NTM-LD) is often difficult. Thus, this study aimed to investigate the impact of the integrity of NTM-LD treatment on treatment outcomes.

MATERIALS AND METHODS

The participants were screened from the National Taiwan University Hospital-Integrative Medical Database (NTUH-iMD) and the Taiwan National Health Insurance Research Database (NHIRD). The longest treatment duration during 3 consecutive months was defined as maximum chemotherapy possession days (MCPDs) and was categorized as low (28-55 days), medium (56-90 days), and maximum (≥91 days). We analyzed microbiological cure and 3-year mortality using MCPDs.

RESULTS

Low, medium, and maximum MCPD groups had 83 (19.2 %), 94 (21.8 %), and 255 (59.0 %) participants in the NTUH-iMD cohort (N = 432) and 1203 (26.5 %), 1251 (27.6 %), and 2084 (45.9 %) participants in the NHIRD cohort (N = 4538), respectively. In the NTUH-iMD cohort, multivariable analysis showed that adjusted hazard ratios (aHRs) of 3-year mortality were 0.51 (95 % CI: 0.29-0.90) and 0.29 (0.18-0.49) in medium and maximum MCPD groups compared with the low MCPD group. The trends of survival benefit by maximum MCPDs were also found in the NHIRD cohort. The maximum MCPD group had 45.9 % participants with microbiologic cure, which was significantly higher than in medium and low MCPD groups (27.7 % and 4.0 %, respectively; p < 0.001).

CONCLUSION

Maximum MCPD for NTM-LD increased microbiological cure and reduced 3-year mortality by 71 % compared with low MCPD group. Maintaining NTM-LD treatment integrity as possible might positively impact disease outcomes.

Relationship Between Clarithromycin Minimum Inhibitory Concentrations and Treatment Responses in Mycobacterium avium Complex Pulmonary Disease

BACKGROUND

Mycobacterium avium complex pulmonary disease (MAC-PD) is a chronic lung condition with rapidly increasing prevalence worldwide. Macrolides like azithromycin and clarithromycin are the backbone of long-term antibiotic therapy for progressive MAC-PD. The impact of minimum inhibitory concentrations (MICs), especially within the susceptible range, for macrolides on treatment responses remains unclear.

METHODS

We analyzed adult patients who started treatment for MAC-PD between 1 March 2009 and 1 March 2022 at Seoul National University Hospital. Patients were categorized into 4 groups according to the clarithromycin MICs of their causative strains at treatment initiation. Logistic regression was employed to evaluate the impact of clarithromycin MICs on the likelihood of microbiological cure. Companion drugs and their MICs, alongside clinical characteristics like age, sex, body mass index, cavity presence, acid-fast bacilli smear positivity, causative species, and erythrocyte sedimentation rate were adjusted in multivariable analysis.

RESULTS

Four-hundred thirty-six patients (median age, 65 years; 34% men) were included. Microbiological cure rates were 51.8%, 51.9%, 50.0%, and 18.2% for patients with clarithromycin MICs ≤0.5, 1-2, 4-8, and ≥32 µg/mL, respectively (P = .181). No significant differences in microbiological cure rates were observed across varying levels of clarithromycin MICs within the susceptible range (≤8 µg/mL). Relative to patients with clarithromycin-susceptible strains, patients with MICs ≥32 µg/mL had an odds ratio of 0.25 for achieving microbiological cure (95% confidence interval [CI]: 0.06-1.07; P = .06).

CONCLUSIONS

Treatment responses were comparable among patients with strains having clarithromycin MICs within the susceptible range but were likely to be worse for patients with strains having MICs ≥32 µg/mL.

Prospective Analysis of urINe LAM to Eliminate NTM Sputum Screening (PAINLESS) study: Rationale and trial design for testing urine lipoarabinomannan as a marker of NTM lung infection in cystic fibrosis

BACKGROUND

Routine screening for nontuberculous mycobacterial (NTM) lung disease is dependent on sputum cultures. This is particularly challenging in the cystic fibrosis (CF) population due to reduced sputum production and low culture sensitivity. Biomarkers of infection that do not rely on sputum may lead to earlier diagnosis, but validation trials require a unique prospective design.

PURPOSE

The rationale of this trial is to investigate the utility of urine lipoarabinomannan (LAM) as a test to identify people with CF with a new positive NTM culture. We hypothesize that urine LAM is a sensitive, non-invasive screening test with a high negative predictive value to identify individuals with a relatively low risk of having positive NTM sputum culture.

STUDY DESIGN

This is a prospective, single-center, non-randomized observational study in adults with CF, 3 years of negative NTM cultures, and no known history of NTM positive cultures. Patients are followed for two year-long observational periods with the primary endpoint being a positive NTM sputum culture within a year of a positive urine LAM result and a secondary endpoint of a positive NTM sputum culture within 3 years of a positive urine LAM result. Study implementation includes remote consent and sample collection to accommodate changes from the COVID-19 pandemic.

CONCLUSIONS

This report describes the study design of an observational study aimed at using a urine biomarker to assist in the diagnosis of NTM lung infection in pwCF. If successful, urine LAM could be used as an adjunct to traditional sputum cultures for routine NTM screening, and replace cultures in low-risk individuals unable to produce sputum.

Effect of Individual Agents on Time to Culture Conversion in Mycobacterium avium Complex Pulmonary Disease

In a cohort of 534 patients treated for Mycobacterium avium complex pulmonary disease, those who failed to achieve culture conversion were older, had higher proportions of males and cavity presence, were more likely to receive clofazimine and aminoglycosides, but less likely to receive rifampicin, and had a shorter overall treatment duration. Time-varying analysis of individual drug effects on time to culture conversion identified rifampicin as being associated with a reduced culture conversion rate (adjusted hazard ratio, 0.959; 95% confidence interval, .924-.995; P = .027), suggesting a potentially negative effect on Mycobacterium avium complex pulmonary disease outcomes, whereas other drugs showed no significant association.

Isolation of Genetically Distinct Strains Within the Same Species During Treatment of Mycobacterium Avium Complex Pulmonary Disease

BACKGROUND

Research on isolating genetically different strains within the same species in patients undergoing treatment for Mycobacterium avium complex (MAC) pulmonary disease (PD) is limited. We investigated the frequency of genetically distinct strains identified within the same species among on-treatment isolates compared with pretreatment isolates throughout the course of MAC-PD treatment.

RESEARCH QUESTION

What is the frequency of genetically distinct strains identified within the same species among pretreatment and on-treatment isolates in patients with MAC-PD?

STUDY DESIGN AND METHODS

We serially collected pretreatment and on-treatment clinical isolates from patients with MAC-PD treated for over 1 month from November 2019 to October 2022 at a tertiary hospital in South Korea. We used multilocus sequence typing (MLST) genotypic analysis to determine whether the on-treatment isolate was a genetically different strain compared with the pretreatment isolate.

RESULTS

Among 327 enrolled patients, we identified the on-treatment isolates of 198 patients as the same species as the pretreatment isolates. The median treatment duration for the 198 patients was 14.4 months (interquartile range, 12.1-16.9 months). Of these patients, MLST analysis showed the presence of a genetically different strain among the on-treatment isolates at least once in 24.7% (49/198) of patients (95% CI, 18.9-31.4) compared with the pretreatment isolate. There were variations in the timing, frequency, and number of distinct strains in these 49 patients.

INTERPRETATION

We identified a genetically distinct strain within the same species at least once in approximately 25% of patients in whom the same species was isolated after the initiation of anti-MAC-PD therapy. These findings may affect the determination of treatment outcomes and corresponding MAC-PD treatment strategies.

Effects of Amikacin Liposome Inhalation Suspension and Amikacin Resistance Development in Patients With Refractory Mycobacterium avium Complex Pulmonary Disease

Background

Amikacin liposome inhalation suspension (ALIS) is key for treating refractory Mycobacterium avium complex pulmonary disease (MAC-PD). However, microbiological efficacy by subtype remains unknown. The frequency and mechanism of amikacin (AMK) resistance during ALIS administration are also unclear.

Methods

We retrospectively analyzed data from refractory MAC-PD patients who received ALIS for at least 6 months as an adjunct to guideline-based therapy at the NHO Kinki Chuo Chest Medical Center. We investigated the efficacy of ALIS and analyzed gene expression and the frequency of AMK resistance.

Results

We enrolled 44 patients (median age, 72.0 years): 19 (43.2%) with the noncavitary nodular bronchiectatic (NC-NB) subtype and 25 (56.8%) with the cavitary subtype. Overall, sputum culture conversion was 56.8% (25/44): 84.2% (16/19) in the NC-NB subtype and 36.0% (9/25) in the cavitary subtype (P = .001). During intermittent dosing, conversion occurred in 50.0% (9/18). In patients with C-reactive protein (CRP) ≥1 mg/dL, cavitary subtype, and clarithromycin (CLM) resistance, the risk ratio for persistently positive cultures was 10.81 (95% CI, 1.66-70.40) compared with those with CRP <1 mg/dL, NC-NB subtype, and CLM susceptibility. Of all participants, 15.9% (7/44) had isolates with AMK resistance (minimum inhibitory concentration ≥128 µg/mL), and of these 71.4% (5/7) had rrs mutations.

Conclusions

Regimens that included ALIS achieved higher culture conversion in NC-NB than cavitary MAC-PD cases. High CRP levels, cavitary disease, and CLM resistance predicted persistent culture positivity. AMK resistance acquired during ALIS administration may limit treatment options for refractory MAC-PD.

Evaluation of treatment response with serial CT in patients with non-tuberculous mycobacterial pulmonary disease

OBJECTIVES

In patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD), the response to treatment is evaluated based on microbiological, clinical, and radiological data. However, little is known about the dynamics of CT findings. The aim of this study was to evaluate CT changes in NTM-PD in order to define radiological criteria for treatment success.

METHODS

Retrospective multicenter study (Hannover, Heidelberg, Gauting). Sixty patients with NTM-PD and at least two consecutive CT scans were included. Scoring for NTM-PD was performed by evaluating variables of bronchiectasis, mucus plugging, bronchiolitis, cavities, nodules, and consolidations on an ordinal scale from 0 to 3. Differences between baseline and follow-up were calculated, and patients with/without cultural conversion were compared using the Mann-Whitney U-test. For paired comparison of the two consecutive CT scans the Wilcoxon test was used.

RESULTS

Comparing patients with and without culture conversion, there were significant differences in temporal changes of bronchiectasis (p < 0.001), cavities (p = 0.006), bronchiolitis (p < 0.001), consolidations (p = 0.004), and total score (p < 0.001). Nodules showed no significant differences between groups (p = 0.060). The Wilcoxon test showed significant differences between both CTs in patients with a microbiological cure for the total score (p < 0.001), cavities (p = 0.005), bronchiolitis (p < 0.001), and consolidations (p = 0.021) with a decrease after microbiological cure, whereas bronchiectasis (p = 0.102) and nodules (p = 0.18) stayed stable. In the case of persistently positive cultures, there was an increase in the total score (p = 0.010) which was attributable to progressive bronchiectasis (p < 0.001).

CONCLUSION

Cavities, consolidations, and bronchiolitis are useful to assess treatment response, whereas bronchiectasis and nodules may remain stable despite successful treatment.

CLINICAL RELEVANCE STATEMENT

Cavities, consolidations, and bronchiolitis can assess treatment response whereas bronchiectasis and nodules may remain stable despite successful treatment. In persistently positive cultures, bronchiectasis showed an increase over time indicating that NTM-PD is a progressive chronic disease.

KEY POINTS

Little is known about CT changes in nontuberculous mycobacteria pulmonary disease (NTM-PD) and criteria to evaluate treatment response. In the case of culture conversion, cavities and bronchiolitis decreased whereas bronchiectasis and nodules remained stable. Cavities and bronchiolitis can evaluate treatment response in NTM, but bronchiectasis and nodules may persist despite successful treatment.

A Rare Pathogenic Masquerader of Pulmonary Disease: A Case Report

This case report details a 61-year-old male patient with a history of chronic obstructive pulmonary disease (COPD) and significant smoking exposure, who presented with progressive anorexia, weight loss, nocturnal sweating, and worsening respiratory symptoms in early 2024. Imaging revealed bi-apical opacities with cavitation, and sputum cultures identified Mycobacterium szulgai, a rare nontuberculous mycobacterium (NTM). The patient was managed with a multi-drug regimen including azithromycin, rifampin, and ethambutol, targeting symptom relief, radiographic stability, and sputum conversion. Early treatment results demonstrated clinical improvement, weight gain, and decreased radiographic abnormalities, although sputum studies remained positive. This case underscores the diagnostic and therapeutic complexities of rare NTM infections in patients with underlying lung disease.

Diversity and antimicrobial resistance profiles of Mycobacterium avium complex clinical isolates in Thailand based on whole genome comparative analysis

The Mycobacterium avium complex (MAC) is a group of closely related nontuberculous mycobacteria that can cause various diseases in humans. In this study, genome sequencing, comprehensive genomic analysis, and antimicrobial susceptibility testing of 66 MAC clinical isolates from King Chulalongkorn Memorial Hospital, Bangkok, Thailand were carried out. Whole-genome average nucleotide identity (ANI) revealed the MAC species distribution, comprising 54 (81.8%) M. intracellulare, 6 (9.1%) M. avium, 5 (7.6%) M. colombiense, and 1 (1.5%) M. timonense. Phylogenetic analysis revealed a high diversity of M. intracellulare isolates and their evolutionary relationships which could be divided into 2 subspecies: M. intracellulare subsp. intracellulare and M. intracellulare subsp. chimaera. In addition, M. intracellulare subsp. chimaera mostly clustered in the distinct clades separated from M. intracellulare strains originating from other countries. Most MAC isolates were resistant to linezolid and moxifloxacin based on phenotypic antimicrobial susceptibility testing. Mutations within rrl gene associated with clarithromycin resistance were detected in M. intracellulare and M. colombiense. The pan-genome analysis presented clade-specific proteins for M. intracellulare, such as PE and PPE protein families. This study provides valuable insights into the genomic diversity and antimicrobial resistance profiles of MAC isolates circulating in Thailand, which are useful for clinical management, guiding the development of targeted diagnostic, and treatment strategies for MAC infections.

Optimal incubation duration of liquid cultures for assessing culture negative conversion in patients with Mycobacterium avium complex and Mycobacterium abscessus pulmonary diseases

PURPOSE

Mycobacterial liquid culturing typically requires six weeks or longer, primarily because of the slow growth rate of Mycobacterium tuberculosis. This study aimed to evaluate the potential of shortening the duration of mycobacterial liquid culturing in healthcare settings with high prevalence rates of non-tuberculous mycobacteria.

METHODS

We retrospectively analyzed the relationship between mycobacterial species and time to positive testing of liquid cultures from sputum samples using the Mycobacteria Growth Indicator Tube system over a 3.5-year period beginning in July 2020 at a university hospital in Japan.

RESULTS

We analyzed 15,147 sputum culture samples and found a 1.1% positivity rate for Mycobacterium tuberculosis complex, while the rates for Mycobacterium avium complex and Mycobacterium abscessus were 17.6% and 2.1%, respectively. The median time to positivity was 17 days for Mycobacterium tuberculosis complex, 9 days for Mycobacterium avium complex, and 4 days for Mycobacterium abscessus. Comparing a 4-week culture period with an eight-week period, the positivity rates for Mycobacterium avium complex and Mycobacterium abscessus were 97.0% and 99.4%, respectively.

CONCLUSION

In settings with a high incidence of non-tuberculous mycobacteria, the basic liquid culturing period can be safely shortened to 4 weeks without significantly compromising detection sensitivity, except for the samples that are highly suspected to contain tuberculosis, extremely slow-growing mycobacteria, smear-positive, or nucleic acid amplification testing positive.

Long-term clinical course of Mycobacterium avium complex pulmonary disease patients with treatment failure

Despite guideline-based therapy, some patients with Mycobacterium avium complex pulmonary disease (MAC-PD) experience treatment failure. We analyzed the clinical courses of 271 patients with treatment-refractory MAC-PD who discontinued therapy after at least 12 months. Patients were categorized into two groups-the retreatment group, who resumed antibiotics due to clinical or radiological deterioration, and the stable group, who did not require antibiotics. Of the study patients, 138 (51%) were in the retreatment group, whereas 133 (49%) were in the stable group. In the multivariate analysis models, an elevated erythrocyte sedimentation rate (adjusted hazard ratio [aHR] =1.01), the presence of a cavity (aHR = 1.75), and the number of lobes affected by bronchiectasis (aHR = 1.21) were associated with the need for retreatment. Our data indicated that approximately 50% of the patients with refractory MAC-PD who discontinued antibiotics eventually required retreatment, which was influenced by the extent of lung destruction or inflammation. These findings can aid in determining treatment strategies for patients with refractory diseases.

Treatment outcomes in NTM-PD in a high TB burden context

BACKGROUND

Non-tuberculous mycobacterial (NTM) pulmonary disease (PD) is a significant concern in China, compounding the existing burden of TB. This review aims to summarise the treatment outcomes for NTM-PD in China.

METHODS

We reviewed the evidence on NTM-PD, including treatment regimens and clinical outcomes, from 17 studies identified through screening of three Chinese biomedical databases.

RESULTS

Antimicrobial treatment showed a microbiological cure rate ranging from 17.2% to 60.0% in studies with ≥50 NTM-PD patients, with lower rates observed among older and malnourished patients. The Mycobacterium chelonae abscessus group (MC-AG) and Mycobacterium avium-intracellulare complex (MAC) were the most prevalent NTM species in China. Higher microbiological cure rates were seen in MAC PD compared with MC-AG PD. The addition of cefoxitin and linezolid improved culture conversion rates in MC-AG-infected patients. One study (n = 24) demonstrated that resecting lesions and chemotherapy led to more favourable clinical outcomes.

CONCLUSION

Treatment regimens recommended in Chinese guidelines yielded poor-to-moderate outcomes for NTM-PD in China, highlighting the need for further research into alternative antimicrobial treatments to improve efficacy.

Significance of changes in cavity after treatment in Mycobacterium avium complex pulmonary disease

Cavities are characteristic radiological features related to increased mycobacterial burden and poor prognosis in Mycobacterium avium complex pulmonary disease (MAC-PD). However, cavity changes following treatment and their clinical implications remain unknown. We aimed to elucidate whether cavity obliteration or reduction in cavity size or wall thickness correlates with microbiological cure. In total, 136 adult patients with cavitary MAC-PD treated for ≥ 6 months between January 1st, 2009, and December 31st, 2021, in a tertiary referral centre in South Korea were enrolled. The cavity with the largest diameter at treatment initiation was tracked for size and thickness changes. Following median treatment of 20.0 months, 74 (54.4%) patients achieved microbiological cure. Cavity obliteration, achieved in 58 (42.6%) patients at treatment completion, was independently associated with microbiological cure. In patients with persistent cavities, size reduction of ≥ 10% was significantly associated with microbiological cure, whereas thickness reduction was not. Five-year mortality rates in patients with cavity obliteration, persistent but reduced cavity, and persistent cavity without shrinkage were 95.6%, 72.1%, and 65.3%, respectively (P < 0.001). In conclusion, cavity obliteration or shrinkage at treatment completion is associated with microbiological cure and reduced mortality in MAC-PD, suggesting that cavity changes could serve as a proxy indicator for treatment response.

The Association Between Sputum Culture Conversion and Mortality in Cavitary Mycobacterium avium Complex Pulmonary Disease

BACKGROUND

The association between treatment outcome and the mortality of patients with Mycobacterium avium complex pulmonary disease (MAC-PD) with cavitary lesions is unclear. This article assessed the impact of culture conversion on mortality in patients with cavitary MAC-PD.

RESEARCH QUESTION

Is the achievement of sputum culture conversion in patients with MAC-PD with cavitary lesions associated with the prognosis?

STUDY DESIGN AND METHODS

From 2002 to 2020, a total of 351 patients with cavitary MAC-PD (105 with the fibrocavitary type and 246 with the cavitary nodular bronchiectatic type), who had been treated with a ≥ 6-month macrolide-containing regimen at a tertiary referral center in South Korea, were retrospectively enrolled in this study. All-cause mortality during the follow-up period was analyzed based on culture conversion at the time of treatment completion.

RESULTS

The cohort had a median treatment duration of 14.7 months (interquartile range [IQR], 13.4-16.8 months). Of the 351 patients, 69.8% (245 of 351) achieved culture conversion, and 30.2% (106 of 351) did not. The median follow-up was 4.4 years (IQR, 2.3-8.3 years) in patients with culture conversion and 3.1 years (IQR, 2.1-4.8 years) in those without. For the patients with and without culture conversion, all-cause mortality was 5.3% vs 35.8% (P < .001), and the 5-year cumulative mortality was 20.0% vs 38.4%, respectively. Cox analysis found that a lack of culture conversion was significantly associated with higher mortality (adjusted hazard ratio, 5.73; 95% CI, 2.86-11.50). Moreover, the 2-year landmark analysis revealed a distinct impact of treatment outcome on mortality.

INTERPRETATION

The mortality rate of patients with cavitary MAC-PD who did not achieve culture conversion was significantly higher than that of those with culture conversion.

Clofazimine serum concentration and safety/efficacy in nontuberculous mycobacterial pulmonary disease treatment

BACKGROUND

Clofazimine (CFZ) has shown promising effects against Mycobacterium avium-intracellulare complex pulmonary disease (MAC-PD) and Mycobacterium abscessus species pulmonary disease (MABS-PD). However, the optimal CFZ dose remains unknown. We aimed to explore the relationship between steady-state CFZ concentration and its safety and efficacy in MAC-PD and MABS-PD.

METHODS

This prospective observational study focused on patients with MAC-PD and MABS-PD treated with CFZ (UMIN 000041053). To understand the safety and efficacy profile of CFZ and elucidate its optimal concentration, we analyzed CFZ-induced pigmentation grade, QTc interval, and culture conversion outcomes in relation to serum CFZ concentration using Student's t-test, a concentration-QTc model, and multivariable logistic regression analysis, respectively. In total, 64 patients (34 with MAC-PD; 30 with MABS-PD) were included.

RESULTS

The steady-state concentration of CFZ was higher in the moderate-to-severe pigmentation group than in the none-to-light pigmentation group (P < 0.001). At a CFZ concentration of 1 mg/L, the QTc interval was prolonged by 17.3 ms (95 % confidence interval [CI], 3.9-25.4) from baseline. Culture conversion was achieved in 33 (51.6 %) patients. The only significant predictor of culture conversion was surgery (adjusted odds ratio, 5.4; 95 % CI, 1.3-38.0). CFZ concentration and MIC of CFZ less than 0.25 mg/L were not associated with culture conversion in this study.

CONCLUSION

CFZ-induced pigmentation and QT interval prolongation are associated with serum CFZ concentrations. CFZ dosage may be optimized by monitoring serum CFZ concentration.

PARK2 as a susceptibility factor for nontuberculous mycobacterial pulmonary disease

BACKGROUND

The genetic signatures associated with the susceptibility to nontuberculous mycobacterial pulmonary disease (NTM-PD) are still unknown. In this study, we performed RNA sequencing to explore gene expression profiles and represent characteristic factor in NTM-PD.

METHODS

Peripheral blood samples were collected from patients with NTM-PD and healthy individuals (controls). Differentially expressed genes (DEGs) were identified by RNA sequencing and subjected to functional enrichment and immune cell deconvolution analyses.

RESULTS

We enrolled 48 participants, including 26 patients with NTM-PD (median age, 58.0 years; 84.6% female), and 22 healthy controls (median age, 58.5 years; 90.9% female). We identified 21 upregulated and 44 downregulated DEGs in the NTM-PD group compared to those in the control group. NTM infection did not have a significant impact on gene expression in the NTM-PD group compared to the control group, and there were no differences in the proportion of immune cells. However, through gene ontology (GO), gene set enrichment analysis (GSEA), and protein-protein interaction (PPI) analysis, we discovered that PARK2 is a key factor associated with NTM-PD. The PARK2 gene, which is linked to the ubiquitination pathway, was downregulated in the NTM-PD group (fold change, - 1.314, P = 0.047). The expression levels of PARK2 remained unaltered after favorable treatment outcomes, suggesting that the gene is associated with host susceptibility rather than with the outcomes of infection or inflammation. The area under the receiver operating characteristic curve for the PARK2 gene diagnosing NTM-PD was 0.813 (95% confidence interval, 0.694-0.932).

CONCLUSION

We identified the genetic signatures associated with NTM-PD in a cohort of Korean patients. The PARK2 gene presents as a potential susceptibility factor in NTM-PD .

Prospective Analysis of urINe LAM to Eliminate NTM Sputum Screening (PAINLESS) study: Rationale and trial design for testing urine lipoarabinomannan as a marker of NTM lung infection in cystic fibrosis

Background

Routine screening for nontuberculous mycobacterial (NTM) lung disease is dependent on sputum cultures. This is particularly challenging in the cystic fibrosis (CF) population due to reduced sputum production and low culture sensitivity. Biomarkers of infection that do not rely on sputum may lead to earlier diagnosis, but validation trials require a unique prospective design.

Purpose

The rationale of this trial is to investigate the utility of urine lipoarabinomannan (LAM) as a test to identify people with CF with a new positive NTM culture. We hypothesize that urine LAM is a sensitive, non-invasive screening test with a high negative predictive value to identify individuals with a relatively low risk of having positive NTM sputum culture.

Study design

This is a prospective, single-center, non-randomized observational study in adults with CF, 3 years of negative NTM cultures, and no known history of NTM positive cultures. Patients are followed for two year-long observational periods with the primary endpoint being a positive NTM sputum culture within a year of a positive urine LAM result and a secondary endpoint of a positive NTM sputum culture within 3 years of a positive urine LAM result. Study implementation includes remote consent and sample collection to accommodate changes from the COVID-19 pandemic.

Conclusions

This report describes the study design of an observational study aimed at using a urine biomarker to assist in the diagnosis of NTM lung infection in pwCF. If successful, urine LAM could be used as an adjunct to traditional sputum cultures for routine NTM screening.

CT findings as predictive factors for treatment failure in Mycobacterium abscessus complex lung disease: a retrospective cohort study

PURPOSE

Mycobacterium abscessus complex (MABC) commonly causes lung disease (LD) and has a high treatment failure rate of around 50%. In this study, our objective is to investigate specific CT patterns for predicting treatment prognosis and monitoring treatment response, thus providing valuable insights for clinical physicians in the management of MABC-LD treatment.

METHODS

We retrospectively assessed 34 patients with MABC-LD treated between January 2015 and December 2020. CT scores for bronchiectasis, cellular bronchiolitis, consolidation, cavities, and nodules were measured at initiation and after treatment. The ability of the CT scores to predict treatment outcomes was analyzed in logistic regression analyses.

RESULTS

The CT scoring system had excellent inter-reader agreement (all intraclass correlation coefficients, > 0.82). The treatment failure (TF) group (17/34; 50%) had higher cavitation diameter (p = 0.049) and extension (p = 0.041) at initial CT and higher cavitation diameter (p = 0.049) and extension (p =0 .045), consolidation (p = 0.022), and total (p = 0.013) scores at follow-up CT than the treatment success (TS) group. The changes of total score and consolidation score (p = 0.049 and 0.024, respectively) increased in the TF group more than the TS group between the initial and follow-up CT. Multivariable logistic regression analysis showed initial cavitation extension, follow-up consolidation extension, and change in consolidation extension (adjusted odds ratio: 2.512, 2.495, and 9.094, respectively, per 1-point increase; all p < 0.05) were significant predictors of treatment failure.

CONCLUSIONS

A high pre-treatment cavitation extension score and an increase in the consolidation extension score during treatment on CT could be alarm signs of treatment failure requiring tailor the treatment of MABC-LD carefully.

Real-World Patients' Diagnosis-to-Treatment Journey with Nontuberculous Mycobacterial Pulmonary Disease: A Cross-Sectional Survey

INTRODUCTION

The incidence and prevalence of nontuberculous mycobacterial pulmonary disease (NTM-PD) are increasing globally. Approximately 80% of NTM-PD cases in Japan and five countries within Europe (Eur5; France, Germany, Italy, Spain, and the UK) are caused by Mycobacterium avium complex (MAC). This study describes the clinical decision-making process associated with the management of patients with NTM-PD in Japan and the Eur5.

METHODS

We analyzed data from a survey conducted between July 2013 and October 2013 among physicians treating patients with NTM-PD in clinical practice to compare the healthcare settings, clinical presentation, and patient management in Japan and the Eur5.

RESULTS

Overall, 619 physicians (Japan, 173; Eur5, 446) participated in the survey. Most patients in Japan (85%) and the Eur5 (79%) were diagnosed with MAC-PD. Patients were managed generally in hospital-based outpatient clinics (117/173, 68%) in Japan and research/teaching hospitals affiliated with medical schools (140/446, 31%) in the Eur5. The most common reason for delaying treatment was the patient's symptoms not being considered serious enough for treatment (55/128, 43%) in Japan and awaiting results of antimicrobial susceptibility testing (44/151, 29%) in the Eur5. Culture negativity was less commonly achieved after treatment in patients in Japan versus those in the Eur5 (31% [73/238] vs. 70% [300/426], p < 0.0001). In treatment phases that were either completed or discontinued, the primary goal was symptomatic improvement, followed by achieving culture conversion, in both Japan and the Eur5. Overall, 19% (16/85) of physicians in Japan and 43% (220/511) in the Eur5 were "entirely satisfied" with their patients' treatment outcomes.

CONCLUSIONS

Similarities and differences exist in the healthcare settings, clinical presentation, and management of patients with NTM-PD in Japan and the Eur5. Insufficient consideration of culture status by physicians, delayed treatment initiation, and symptom-based cessation emphasize the need for educational efforts on the guideline-based strategies.

Adjuvant surgical treatment of non-tuberculous mycobacterial lung disease in chronic thromboembolic pulmonary hypertension: A first case report

Pulmonary hypertension (PH) is not considered a known risk factor for non-tuberculous mycobacterial lung disease (NTM-LD), despite that many studies state that incidence is almost equal to other chronic lung diseases. Current standard of care for NTM-LD consists in multidrug antibiotic regimen for several months. However, it results in negative culture conversion in a minority of cases. Therefore, when feasible an adjuvant surgical approach is indicated. In this case report we highlight the importance of multidisciplinary team discussion in providing the best therapeutic strategy in presence of significant comorbidities like chronic thromboembolic pulmonary hypertension.

Drinking Water Microbiota, Entero-Mammary Pathways, and Breast Cancer: Focus on Nontuberculous Mycobacteria

The prospect of drinking water serving as a conduit for gut bacteria, artificially selected by disinfection strategies and a lack of monitoring at the point of use, is concerning. Certain opportunistic pathogens, notably some nontuberculous mycobacteria (NTM), often exceed coliform bacteria levels in drinking water, posing safety risks. NTM and other microbiota resist chlorination and thrive in plumbing systems. When inhaled, opportunistic NTM can infect the lungs of immunocompromised or chronically ill patients and the elderly, primarily postmenopausal women. When ingested with drinking water, NTM often survive stomach acidity, reach the intestines, and migrate to other organs using immune cells as vehicles, potentially colonizing tumor tissue, including in breast cancer. The link between the microbiome and cancer is not new, yet the recognition of intratumoral microbiomes is a recent development. Breast cancer risk rises with age, and NTM infections have emerged as a concern among breast cancer patients. In addition to studies hinting at a potential association between chronic NTM infections and lung cancer, NTM have also been detected in breast tumors at levels higher than normal adjacent tissue. Evaluating the risks of continued ingestion of contaminated drinking water is paramount, especially given the ability of various bacteria to migrate from the gut to breast tissue via entero-mammary pathways. This underscores a pressing need to revise water safety monitoring guidelines and delve into hormonal factors, including addressing the disproportionate impact of NTM infections and breast cancer on women and examining the potential health risks posed by the cryptic and unchecked microbiota from drinking water.

The Impact of Trehalose Dimycolate on the Clinical Course of Mycobacterium avium Complex Pulmonary Disease

Rationale: The clinical implications of trehalose 6,6'-dimycolate (TDM) in nontuberculous mycobacterial pulmonary disease have not been studied. Objectives: To examine the presence of TDM in clinical isolates obtained from patients with Mycobacterium avium complex (MAC) pulmonary disease (PD) and its impact on disease severity and treatment outcomes. Methods: We analyzed clinical isolates from patients with diagnoses of MAC PD at Seoul National University Hospital between January 1, 2019, and December 31, 2021. The lipids were extracted from clinical isolates obtained at the time of diagnosis using mass spectrometry. Mass peaks between 300 and 3,500 m/z were obtained, and the peak patterns of the total lipids were analyzed. Results: TDM was identified in clinical isolates from 176 of 343 patients. Cavities were more prevalent in patients with TDM-negative isolates (19.8%) than in those with TDM-positive isolates (10.2%) (P = 0.015). The time to antibiotic treatment was shorter in patients with TDM-negative isolates (4 mo [interquartile range, 2-10 mo]) than in those with TDM-positive isolates (7 mo [interquartile range, 3-16 mo]) (P = 0.032). Patients with TDM-negative isolates had a significantly lower proportion of culture conversions (P = 0.012). TDM was associated with higher likelihood of culture conversion (adjusted hazard ratio, 2.29; P = 0.035). Conclusions: TDM-negative isolates were linked to a higher occurrence of cavities, earlier initiation of treatment, and worse treatment outcome in patients with MAC PD.

Proposed Etiotypes for Chronic Obstructive Pulmonary Disease: Controversial Issues

The 2023 Global Initiative for Chronic Obstructive Lung Disease (GOLD) revised the definition of chronic obstructive pulmonary disease (COPD) to broadly include a variety of etiologies. A new taxonomy, composed of etiotypes, aims to highlight the heterogeneity in causes and pathogenesis of COPD, allowing more personalized management strategies and emphasizing the need for targeted research to understand and manage COPD better. However, controversy arises with including some diseases under the umbrella term of COPD, as their clinical presentations and treatments differ from classical COPD, which is smoking-related. COPD due to infection (COPD-I) and COPD due to environmental exposure (COPD-P) are classifications within the new taxonomy. Some disease entities in these categories show distinct clinical features and may not benefit from conventional COPD treatments, raising questions about their classification as COPD subtypes. There is also controversy regarding whether bronchiectasis with airflow limitations should be classified as an etiotype of COPD. This article discusses controversial issues associated with the proposed etiotypes for COPD in terms of COPD-I, COPD-P, and bronchiectasis. While the updated COPD definition by GOLD 2023 is a major step towards recognizing the disease's complexity, it also raises questions about the classification of related respiratory conditions. This highlights the need for further research to improve our understanding and approach to COPD management.

Growing from common ground: nontuberculous mycobacteria and bronchiectasis

Bronchiectasis and nontuberculous mycobacteria (NTM) are intricately intertwined, with NTM capable of being both a cause and consequence of bronchiectatic disease. This narrative review focuses on the common ground of bronchiectasis and NTM pulmonary disease (NTM-PD) in terms of diagnostic approach, underlying risk factors and treatment strategies. NTM-PD diagnosis relies on a combination of clinical, radiological and microbiological criteria. Although their epidemiology is complicated by detection and reporting biases, the prevalence and pathogenicity of NTM species vary geographically, with Mycobacterium avium complex and Mycobacterium abscessus subspecies most frequently isolated in bronchiectasis-associated NTM-PD. Diagnosis of nodular bronchiectatic NTM-PD should prompt investigation of host factors, including disorders of mucociliary clearance, connective tissue diseases and immunodeficiencies, either genetic or acquired. Treatment of NTM-PD in bronchiectasis involves a multidisciplinary approach and considers the (sub)species involved, disease severity and comorbidities. Current guideline-based antimicrobial treatment of NTM-PD is considered long, cumbersome and unsatisfying in terms of outcomes. Novel treatment regimens and strategies are being explored, including rifampicin-free regimens and inclusion of clofazimine and inhaled antibiotics. Host-directed therapies, such as immunomodulators and cytokine-based therapies, might enhance antimycobacterial immune responses. Optimising supportive care, as well as pathogen- and host-directed strategies, is crucial, highlighting the need for personalised approaches tailored to individual patient needs. Further research is warranted to elucidate the complex interplay between host and mycobacterial factors, informing more effective management strategies.

Long-term Outcomes of Adjunctive Lung Resection for Nontuberculous Mycobacteria Pulmonary Disease

Background

Adjunctive lung resection is recommended for select patients with nontuberculous mycobacteria (NTM) pulmonary disease (PD). However, data are limited on long-term recurrence rates in patients infected with major pathogens, including Mycobacterium avium complex (MAC) and Mycobacterium abscessus (MABC).

Methods

In this prospective observational study, we retrospectively analyzed data from 125 patients with MAC-PD (n = 90) or MABC-PD (n = 35) who underwent adjunctive lung resection. We evaluated microbiological response, postoperative complications, recurrence, and all-cause mortality over a median 80-month follow-up.

Results

Persistent culture positivity (64%) was the most common indication for surgery, followed by hemoptysis, recurrent pneumonia, or radiologic deterioration. Postoperative complications occurred in 18 (14%) patients, with no surgery-related deaths. Treatment outcomes did not significantly differ between the MAC- and MABC-PD groups. Cure with culture conversion was achieved in 112 (90%) patients. Recurrence occurred in 37 (33%) of 112 patients, of which 18 (49%) cases were attributed to reinfection by different NTM species or subspecies. The MAC group had higher recurrence rates than the MABC group (Kaplan-Meier curve, log-rank test, P = .043) and was significantly associated with recurrence in the multivariable analysis (adjusted hazard ratio, 2.71; 95% CI, 1.23-5.99). However, mortality was higher in the MABC-PD group than the MAC-PD group (7/35 vs 4/90, P = .006).

Conclusions

Adjunctive lung resection with antibiotics helps to reduce bacterial burden and manage symptoms in patients with NTM-PD. However, it does not prevent recurrence, which is mostly caused by reinfection.

Improvement in Health-Related Quality of Life Following Antibiotic Treatment in Nontuberculous Mycobacterial Pulmonary Disease: Initial Analysis of the NTM-KOREA Cohort

BACKGROUND

Improving health-related quality of life (HRQOL) has emerged as a priority in the management of nontuberculous mycobacterial pulmonary disease (NTM-PD). We aimed to evaluate HRQOL and its changes after 6 months' treatment in patients with NTM-PD.

METHODS

The NTM-KOREA is a nationwide prospective cohort enrolling patients initiating treatment for NTM-PD in 8 institutions across South Korea. We conducted the Quality of Life-Bronchiectasis (QOL-B) at 6-month intervals and evaluated baseline scores (higher scores indicate better quality of life) and changes after 6 months' treatment. Multivariate logistic regression was performed to identify factors associated with improvement in the QOL-B physical functioning and respiratory symptoms domains.

RESULTS

Between February 2022 and August 2023, 411 patients were included in the analysis. Baseline scores (95% confidence interval [CI]) for physical functioning and respiratory symptoms were 66.7 (46.7-86.7) and 81.5 (70.4-92.6), respectively. Among 228 patients who completed the QOL-B after 6 months' treatment, improvements in physical functioning and respiratory symptoms were observed in 61 (26.8%) and 71 (31.1%) patients, respectively. A lower score (adjusted odds ratio; 95% CI) for physical functioning (0.93; 0.91-0.96) and respiratory symptoms (0.92; 0.89-0.95) at treatment initiation was associated with a greater likelihood of physical functioning and respiratory symptom improvement, respectively; achieving culture conversion was not associated with improvement in physical functioning (0.62; 0.28-1.39) or respiratory symptoms (1.30; 0.62-2.74).

CONCLUSIONS

After 6 months of antibiotic treatment for NTM-PD, HRQOL improved in almost one-third, especially in patients with severe initial symptoms, regardless of culture conversion.

CLINICAL TRIALS REGISTRATION

ClinicalTrials.gov identifier: NCT03934034.

Minimum inhibitory concentrations of azithromycin in clinical isolates of Mycobacterium avium complex in Japan

The latest guidelines include azithromycin as a preferred regimen for treating Mycobacterium avium complex (MAC) pulmonary disease. However, serially collected susceptibility data on clinical MAC isolates are limited, and no breakpoints have been determined. We investigated the minimum inhibitory concentrations (MICs) of azithromycin and clarithromycin for all MAC strains isolated in 2021 from a single center in Japan, excluding duplicates. The MICs were determined using a panel based on the microbroth dilution method, according to the latest Clinical and Laboratory Standards Institute recommendations. The MICs were determined for 318 MAC strains. Although there was a significant positive correlation between the MICs of azithromycin and clarithromycin, the MICs of azithromycin tended to be higher than those of clarithromycin. Among the cases in which the strains were isolated, 18 patients initiated treatment, including azithromycin treatment, after sample collection. Some patients infected with stains with relatively high azithromycin MICs achieved a microbiological cure with azithromycin-containing regimens. This study revealed a higher MIC distribution for azithromycin than clarithromycin, raising questions about the current practice of estimating azithromycin susceptibility based on the clarithromycin susceptibility test result. However, this was a single-center study that included only a limited number of cases treated with azithromycin. Therefore, further multicenter studies that include a greater number of cases treated with azithromycin are warranted to verify the distribution of azithromycin MICs and examine the correlation between azithromycin MICs and treatment effectiveness.IMPORTANCEThe macrolides serve as key drugs in the treatment of pulmonary Mycobacterium avium complex infection, and the administration of macrolide should be guided by susceptibility test results. Azithromycin is recommended as a preferred choice among macrolides, surpassing clarithromycin; however, drug susceptibility testing is often not conducted, and clarithromycin susceptibility is used as a surrogate. This study represents the first investigation into the minimum inhibitory concentration of azithromycin on a scale of several hundred clinical isolates, revealing an overall tendency for higher minimum inhibitory concentrations compared with clarithromycin. The results raise questions about the appropriateness of using clarithromycin susceptibility test outcomes for determining the administration of azithromycin. This study highlights the need for future discussions on the clinical breakpoints of azithromycin, based on large-scale clinical research correlating azithromycin susceptibility with treatment outcomes.

Antimicrobial susceptibility of Mycobacterium abscessus and treatment of pulmonary and extra-pulmonary infections

BACKGROUND

Mycobacterium abscessus (MAB) is the mycobacterial species least susceptible to antimicrobials. Infections are difficult to treat, and cure rates are below 50% even after a combination of 4-5 drugs for many months.

OBJECTIVES

To examine antimicrobial susceptibilities and treatment recommendations in light of what is known about mechanisms of resistance and pharmacodynamics/pharmacokinetics (PK/PD) interactions.

SOURCES

Original papers on the topics of 'antimicrobials', 'susceptibility', 'treatment', and 'outcome' from 2019 onwards, in the context of the evidence brought by the guidelines published in 2020 for pulmonary infections.

CONTENT

MAB is susceptible in vitro to only a few antimicrobials. Breakpoints were set by the Clinical and Laboratory Standards Institute and are revised by the European Committee on Antimicrobial Susceptibility Testing for epidemiological cut-off values. Innate resistance is due to multiple resistance mechanisms involving efflux pumps, inactivating enzymes, and low drug-target affinity. In addition, MAB may display acquired resistance to macrolides and amikacin through mutations in drug binding sites. Treatment outcomes are better for macrolide-based combinations and MAB subspecies massiliense. New compounds in the family of cyclines, oxazolidinones, and penem-β-lactamase inhibitor combinations (described in another paper), as well as bedaquiline, a new antituberculous agent, are promising, but their efficacy remains to be proven. PK/PD studies, which are critical for establishing optimal dosing regimens, were mainly done for monotherapy and healthy individuals.

IMPLICATIONS

Medical evidence is poor, and randomized clinical trials or standardized cohorts are needed to compare outcomes of patients with similar underlying disease, clinical characteristics, and identified MAB subspecies/sequevar. Microbiological diagnosis and susceptibility testing need to be harmonized to enable the comparison of agents and the testing of new compounds. Testing antimicrobial combinations requires new methods, especially for PK/PD parameters. Molecular testing may help in assessing MAB resistance prior to treatment. New antimicrobials need to be systematically tested against MAB to find an effective antimicrobial regimen.

Drugs for treating infections caused by non-tubercular mycobacteria: a narrative review from the study group on mycobacteria of the Italian Society of Infectious Diseases and Tropical Medicine

BACKGROUND

Non-tuberculous mycobacteria (NTM) are generally free-living organism, widely distributed in the environment, with sporadic potential to infect. In recent years, there has been a significant increase in the global incidence of NTM-related disease, spanning across all continents and an increased mortality after the diagnosis has been reported. The decisions on whether to treat or not and which drugs to use are complex and require a multidisciplinary approach as well as patients' involvement in the decision process.

METHODS AND RESULTS

This review aims at describing the drugs used for treating NTM-associated diseases emphasizing the efficacy, tolerability, optimization strategies as well as possible drugs that might be used in case of intolerance or resistance. We also reviewed data on newer compounds highlighting the lack of randomised clinical trials for many drugs but also encouraging preliminary data for others. We also focused on non-pharmacological interventions that need to be adopted during care of individuals with NTM-associated diseases CONCLUSIONS: Despite insufficient efficacy and poor tolerability this review emphasizes the improvement in patients' care and the needs for future studies in the field of anti-NTM treatments.

Clinical Characteristics and Treatment Outcomes of Pulmonary Diseases Caused by Coinfections With Multiple Nontuberculous Mycobacterial Species

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, P < 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, P < 0.001). Mycobacterium avium complex (MAC) and M. abscessus and M. massiliense (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.

Beyond Symptoms: Radiologic identification of asymptomatic Mycobacterium avium complex pulmonary infections

BACKGROUND

Although international nontuberculous mycobacterial pulmonary disease (NTM-PD) guidelines highlight symptom presence at diagnosis, the clinical characteristics of asymptomatic Mycobacterium avium complex pulmonary infection (MAC-PI) patients remain understudied. We clarified the clinical characteristics and course of asymptomatic MAC-PI patients.

METHODS

We retrospectively analyzed 200 consecutive patients with MAC-PIs and adequate available data who newly met the microbiological and radiological criteria for NTM-PD at Fukujuji Hospital from January 2018 to June 2020. We compared the clinical characteristics and course of asymptomatic patients with symptomatic patients and evaluated factors influencing treatment initiation through multivariate analysis.

RESULTS

111 patients were symptomatic and 89 were asymptomatic at diagnosis. While the proportion was significantly lower than that in the symptomatic group (28.8 %), 15.7 % of asymptomatic group patients had cavitary lesions (P = 0.042). In the asymptomatic group, treatments were initiated in 38 (42.7 %) patients, and cavitary lesions, a positive acid-fast bacilli smear, and younger age were independent risk factors for treatment initiation. Among 22 (57.9 %) patients who experienced disease progression necessitating treatment during follow-up, 13 (34.2 %) displayed radiological progression without any worsening of symptoms. Agents used for treatment were consistent across the groups, with no significant differences in culture conversion, microbiological recurrence rates, or spontaneous culture conversion rates.

CONCLUSION

Routine health checkups and radiological examinations can detect clinically important MAC-PIs even in the absence of symptoms. Considering that the clinical course of asymptomatic MAC-PI patients is largely similar to that of symptomatic patients, timely and appropriate management and intervention are essential for all MAC-PI patients.

Safety and Efficacy of Clofazimine as an Alternative for Rifampicin in Mycobacterium avium Complex Pulmonary Disease Treatment: Outcomes of a Randomized Trial

BACKGROUND

Results of retrospective studies have suggested clofazimine as an alternative for rifampicin in the treatment of Mycobacterium avium complex pulmonary disease (MAC-PD).

RESEARCH QUESTION

Is a treatment regimen consisting of clofazimine-ethambutol-macrolide noninferior to the standard treatment regimen (rifampicin-ethambutol-macrolide) in the treatment of MAC-PD?

STUDY DESIGN AND METHODS

In this single-center, nonanonymized clinical trial, adult patients with MAC-PD were randomly assigned in a 1:1 ratio to receive rifampicin or clofazimine as adjuncts to an ethambutol-macrolide regimen. The primary outcome was sputum culture conversion following 6 months of treatment.

RESULTS

Forty patients were assigned to receive either rifampicin (n = 19) or clofazimine (n = 21) in addition to ethambutol and a macrolide. Following 6 months of treatment, both arms showed similar percentages of sputum culture conversion based on an intention-to-treat analysis: 58% (11 of 19) for rifampicin and 62% (13 of 21) for clofazimine. Study discontinuation, mainly due to adverse events, was equal in both arms (26% vs 33%). Based on an on-treatment analysis, sputum culture conversion following 6 months of treatment was 79% in both groups. In the clofazimine arm, diarrhea was more prevalent (76% vs 37%; P = .012), while arthralgia was more frequent in the rifampicin arm (37% vs 5%; P = .011). No difference in the frequency of corrected QT interval prolongation was seen between groups.

INTERPRETATION

A clofazimine-ethambutol-macrolide regimen showed similar results to the standard rifampicin-ethambutol-macrolide regimen and should be considered in the treatment of MAC-PD. The frequency of adverse events was similar in both arms, but their nature was different. Individual patient characteristics and possible drug-drug interactions should be taken into consideration when choosing an antibiotic regimen for MAC-PD.

CLINICAL TRIAL REGISTRATION

EudraCT; No.: 2015-003786-28; URL: https://eudract.ema.europa.eu.

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.

OPTIMA: An Open-Label, Noncomparative Pilot Trial of Inhaled Molgramostim in Pulmonary Nontuberculous Mycobacterial Infection

Rationale: Inhaled granulocyte-macrophage colony-stimulating factor (GM-CSF) has been proposed as a potential immunomodulatory treatment for nontuberculous mycobacterial (NTM) infection.Objectives: This open-label, noncomparative pilot trial investigated the efficacy and safety of inhaled GM-CSF (molgramostim nebulizer solution) in patients with predominantly treatment-refractory pulmonary NTM infection (Mycobacterium avium complex [MAC] and M. abscessus [MABS]), either in combination with ongoing guideline-based therapy (GBT) or as monotherapy in patients who had stopped GBT because of lack of efficacy or intolerability.Methods: Thirty-two adult patients with refractory NTM infection (MAC, n = 24; MABS, n = 8) were recruited into two cohorts: those with (n = 16) and without (n = 16) ongoing GBT. Nebulized molgramostim 300 μg/d was administered over 48 weeks. Sputum cultures and smears and clinical assessments (6-min-walk distance, symptom scores, Quality of Life-Bronchiectasis Questionnaire score, and body weight) were collected every 4 weeks during treatment and 12 weeks after the end of treatment. The primary endpoint was sputum culture conversion, defined as three consecutive monthly negative cultures during the treatment period.Results: Eight patients (25%) achieved culture conversion on treatment (seven [29.2%] patients with MAC infection, one [12.5%] patient with MABS infection); in four patients, this was durable after the end of treatment. Of the 24 patients with MAC infection, an additional 4 patients had a partial response, converting from smear positive at baseline to smear negative at the end of treatment, and time to positivity in liquid culture media increased. Two of these patients sustained negative cultures from the end of treatment. Other clinical endpoints were unchanged. Serious adverse events were mainly pulmonary exacerbations or worsening NTM infection. Three deaths, not treatment related, were reported.Conclusions: In this population of patients with severe NTM disease, molgramostim was safe and well tolerated. Sputum culture conversion rates for patients with MAC infection (29.2%) were greater than reported for similar refractory MAC cohorts managed with GBT alone. Less benefit was seen for MABS infection. No serious safety concerns were identified. Further evaluation in a larger cohort is warranted.Clinical trial registered with www.clinicaltrials.gov (NCT03421743).

Clinical course of nontuberculous mycobacterial pulmonary disease in patients with rheumatoid arthritis

OBJECTIVES

The impact of rheumatoid arthritis (RA) on nontuberculous mycobacterial pulmonary disease (NTM-PD) has not been well established. In this study, we investigated the clinical course of NTM-PD in patients with RA and the impact of RA on the prognosis of NTM-PD.

METHODS

We analyzed patients who developed NTM-PD after being diagnosed with RA from January 2004 to August 2023 at a tertiary referral hospital in South Korea. The patient's baseline characteristics, clinical course, and prognosis were evaluated. An optimal matching analysis was performed to measure the impact of RA on the risk of mortality.

RESULTS

During the study period, 18 patients with RA [median age, 68 years; interquartile range (IQR) 59-73; female, 88.9%] developed NTM-PD. The median interval between RA diagnosis and subsequent NTM-PD development was 14.8 years (IQR, 8.6-19.5). At a median of 30 months (IQR, 27-105) after NTM-PD diagnosis, 10 of 18 (55.6%) patients received anti-mycobacterial treatment for NTM-PD and 5 (50.0%) patients achieved microbiological cure. When matched to patients with NTM-PD but without RA, patients with both RA and NTM-PD had a higher risk of mortality (adjusted hazard ratio, 8.14; 95% confidence interval, 2.43-27.2).

CONCLUSION

NTM-PD occurring after RA is associated with a higher risk of mortality than NTM-PD in the absence of RA.

Treatment Outcomes of Clofazimine-Containing Regimens in Severe Mycobacterium avium Complex Pulmonary Disease

Background

Clofazimine is suggested as a promising drug for the treatment of nontuberculous mycobacterial pulmonary disease. However, the role of clofazimine in severe Mycobacterium avium complex pulmonary disease (MAC-PD) remains unclear. In this study, we investigated the treatment outcomes of patients with severe MAC-PD treated with regimens containing clofazimine.

Methods

This study included patients diagnosed with severe MAC-PD at Seoul National University Hospital who underwent anti-mycobacterial treatment between 1 January 2011 and 31 December 2022. We assessed the rate of culture conversion within 6 months and microbiological cure in patients receiving clofazimine-containing regimens, considering the dose and duration of clofazimine administration.

Results

A total of 170 patients with severe MAC-PD, treated with regimens containing clofazimine, were included in the analysis. The median age of patients was 68 years (interquartile range, 59-75 years), with a female predominance (n = 114 [67.1%]). Cavities were identified in 121 patients (71.2%). Within 6 months, 77 patients (45.3%) achieved culture conversion, and 84 of 154 (54.6%) patients attained microbiological cure. The dose of clofazimine (100 mg vs 50 mg) was not associated with culture conversion (adjusted odds ratio [aOR], 0.64 [95% confidence interval {CI}, .29-1.42]) or microbiological cure (aOR, 1.21 [95% CI, .52-2.81]). The microbiological cure rate reached 71.0% when clofazimine was administered for 6-12 months, compared to 23.1% when administered for <6 months.

Conclusions

Clofazimine demonstrated a relatively favorable efficacy in severe MAC-PD, regardless of the maintenance dose. This effect was more pronounced when administered for a duration exceeding 6 months.

Post-treatment Radiographic Severity and Mortality in Mycobacterium avium Complex Pulmonary Disease

Rationale: Imaging studies are widely performed when treating Mycobacterium avium complex pulmonary disease (MAC-PD); however, the clinical significance of post-treatment radiographic change is unknown. Objectives: To determine whether a deep neural network trained with pulmonary tuberculosis could adequately score the radiographic severity of MAC-PD and then to examine relationships between post-treatment radiographic severity and its change from baseline and long-term prognosis. Methods: We retrospectively collected chest radiographs of adult patients with MAC-PD treated for ⩾6 months at baseline and at 3, 6, 9, and 12 months of treatment. We correlated the radiographic severity score generated by a deep neural network with visual and clinical severity as determined by radiologists and mycobacterial culture status, respectively. The associations between the score, improvement from baseline, and mortality were analyzed using Cox proportional hazards regression. Results: In total, 342 and 120 patients were included in the derivation and validation cohorts, respectively. The network's severity score correlated with radiologists' grading (Spearman coefficient, 0.40) and mycobacterial culture results (odds ratio, 1.02; 95% confidence interval [CI], 1.0-1.05). A significant decreasing trend in the severity score was observed over time (P < 0.001). A higher score at 12 months of treatment was independently associated with higher mortality (adjusted hazard ratio, 1.07; 95% CI, 1.03-1.10). Improvements in radiographic scores from baseline were associated with reduced mortality, regardless of culture conversion (adjusted hazard ratio, 0.42; 95% CI, 0.22-0.80). These findings were replicated in the validation cohort. Conclusions: Post-treatment radiographic severity and improvement from baseline in patients with MAC-PD were associated with long-term survival.

The role of treatment regimen and duration in treating patients with Mycobacterium avium complex lung disease: A real-world experience and case-control study

PURPOSE

The treatment advantage of guideline-based therapy (GBT) in Mycobacterium avium complex lung disease (MAC-LD) is well-known. However, GBT is not always feasible. The aim of the study was to analyze the relationship of treatment regimens and duration with outcomes.

MATERIALS AND METHODS

This study screened patients with MAC-LD from Jan 2011 to Dec 2020 and enrolled those who received treatment. The treatment regimens were categorized to triple therapy (three active drugs) and non-triple therapy. The favorable outcomes included microbiological cure or clinical cure if no microbiologic persistence.

RESULTS

A total of 106 patients with MAC-LD were enrolled. Among them, 88 subjects (83 %) received triple therapy, 58 (54.7 %) had MAC treatment >12 months, and 66 (62.3 %) had favorable outcomes. Patients receiving triple therapy (90.9 % vs. 67.5 %, p = 0.008) and treatment >12 months (62.1 % vs. 42.5 %, p = 0.07) had higher proportion of favorable outcomes than unfavorable outcomes. Multivariable logistic regression analysis showed that age >65, comorbidities of COPD and prior tuberculosis, low hemoglobin, and high MAC burden were independent risk factors of unfavorable outcome. In contrast, triple therapy (OR: 0.018, 95 % CI: 0.04-0.78, p = 0.022) and treatment duration >12 months (OR: 0.20, 95 % CI: 0.055-0.69, p = 0.012) were protective factors against unfavorable outcome.

CONCLUSIONS

Triple therapy including GBT, and treatment more than 12 months achieved more favorable outcome. Maintenance of triple therapy, but not reducing the number of active drugs, might be an acceptable alternative of GBT.

Challenges and knowledge gaps in the management of non-tuberculous mycobacterial pulmonary disease in sub-Saharan African countries with a high tuberculosis burden: a scoping review

INTRODUCTION

In sub-Saharan African (SSA) countries endemic for tuberculosis (TB), previous TB is a significant risk factor for non-tuberculous mycobacterial pulmonary disease (NTM-PD). The deployment of GeneXpert MTB/RIF in pulmonary TB diagnostic work-up regularly identifies symptomatic patients with a positive smear microscopy but negative GeneXpert, indicative of NTM presence. This scoping review outlines recent evidence for NTM-PD diagnosis and management in SSA.

OBJECTIVE

The review's objective was to outline the risk factors, available diagnostics, management options and outcomes of NTM-PD in high-burden TB settings in SSA using the population-concept-context framework.

DESIGN AND DATA SOURCES

We searched existing literature from PubMed, Web of Science, African Journals Online, Google Scholar and grey literature. Studies published between January 2005 and December 2022 were retained. Data were extracted into Rayyan software and Mendeley and summarised using Excel.

RESULTS

We identified 785 potential articles, of which 105 were included in the full-text review, with 7 papers retained. Included articles used international criteria for diagnosing NTM-PD. Multiple papers were excluded due to non-application of the criteria, suggesting challenging application in the SSA setting. Identified risk factors include previous TB, smoking and mining. Most commonly, chest radiography and not CT was used for the radiological diagnosis of PD, which may miss early changes related to NTM-PD. Molecular methods for NTM species identification were employed in research settings, usually at referral centres, but were unavailable for routine care. Most studies did not report a standardised approach to treatment and they were not offered treatment for the specific disease, marking a lack of guidance in treatment decision-making. When treatment was provided, the outcome was often not reported due to the lack of implementation of standardised outcome definitions.

CONCLUSIONS

These outlined challenges present a unique opportunity for researchers to undertake further studies in NTM-PD and proffer solutions more applicable to SSA.

Change of erythrocyte sedimentation rate as prognostic biomarker for Mycobacterium avium complex pulmonary disease through anti-mycobacterial treatment

BACKGROUND

It remains unclear whether erythrocyte sedimentation rate (ESR) accurately predicts prognosis during treatment and how ESR changes.

OBJECTIVES

We aimed to assess the predictive values of ESR as a prognostic factor of Mycobacterium avium complex pulmonary disease (MAC-PD) while on anti-mycobacterial treatment and its changes according to the treatment responses.

DESIGN

This study is a retrospective cohort study.

METHODS

This study included patients aged 18 years or older who initiated anti-mycobacterial treatment for MAC-PD at Seoul National University Hospital between January 1, 2009 and March 31, 2022. ESR should be measured at least twice, with a minimum interval of 3 months, during the initial 12 months from the commencement of antibiotic treatment. A mixed linear regression and Cox proportional-hazards models were used to analyze repeated ESR data and the association with patient survival.

RESULTS

Of a total of 825 patients who initiated antibiotic treatment for MAC-PD, 369 patients were included in the analysis. Increased levels of ESR during the treatment process were associated with a higher risk of mortality (adjusted hazard ratio 1.03; 95% confidence interval, 1.02-1.03) after adjusting age, sex, comorbidities, presence of cavity, acid-fast bacilli smear positivity, and culture conversion at 12 months. During the treatment, ESR at 12 months of treatment significantly decreased compared to baseline ESR in both the culture-converted and not-converted groups, which was categorized based on whether the culture conversion was achieved within the 12 months after treatment initiation.

CONCLUSION

ESR predicted mortality during treatment and decreased over time, regardless of treatment outcomes. Our results underscore the importance of administering anti-mycobacterial treatment even in patients who did not achieve a microbiological cure.

Mycobacterium avium complex pulmonary disease patients with limited treatment options

How to identify MAC-PD patients with limited treatment options: an expert consensus https://bit.ly/3QwLQ8T.

The Clinical Implications of Serum Carbohydrate Antigen 19-9 Levels in Patients with Nontuberculous Mycobacteria Pulmonary Disease

Serum carbohydrate antigen 19-9 (CA19-9) levels can increase in nontuberculous mycobacteria pulmonary disease (NTM-PD), and the levels correlate with disease activity. We compared the clinical characteristics of NTM-PD patients with and without elevated CA19-9 levels and evaluated its association with antibiotic response in a retrospective study of NTM-PD patients diagnosed between January 1994 and December 2020. We analyzed 1112 patients who had serum CA19-9 measured: 322 with elevated CA19-9 and 790 with normal CA19-9. The erythrocyte sedimentation rate and C-reactive protein levels were significantly higher in the elevated CA19-9 group (p < 0.001 and p = 0.029, respectively). The 1-year culture conversion rate after antibiotics did not differ between the elevated (n = 206) and normal (n = 377) CA19-9 groups (80% vs. 72%, p = 0.055). Analysis of a subset of 434 patients revealed that current smoking, bronchiectasis, acid-fast bacilli smear positivity, and the M. abscessus strain significantly reduced microbiological cure rates. Serum CA 19-9 levels did not have a significant association with microbiological cure in a multivariate analysis. These findings suggest that the role of serum CA19-9 in predicting antibiotic treatment outcomes is limited, and that elevated CA19-9 does not necessarily indicate a poor outcome.

Pulmonary Mycobacterium abscessus infection treated in combination with inhaled tigecycline

Pulmonary disease caused by Mycobacterium abscessus is difficult to treat, as there is currently no reliable evidence-based treatment. Treatment is long, complex and has many side effects. In this case, we report a patient with treatment-refractory pulmonary M abscessus disease, treated with inhaled tigecycline. Treatment with inhaled tigecycline lasted 15 months with comparably limited side effects. There were no positive mycobacterial cultures in the follow-up period of 2 years. Inhaled tigecycline is an option in the treatment of pulmonary M. abscessus when first-line treatment fails. Additional research should investigate this further.

Successful addition of topical antibiotic treatment after surgery in treatment-refractory nontuberculous mycobacterial skin and soft tissue infections

Treatment of skin and soft tissue infections with nontuberculous mycobacteria sometimes fails despite repeated debridements and long-term systemic antibiotic therapy. These treatment-refractory infections can cause significant morbidity and pose a treatment challenge. Following surgery, we treated three patients with negative pressure wound therapy with the instillation and dwell time of topical antibiotics, in addition to systemic antibiotic treatment. Treatment was successful and well tolerated, except for some local irritation.

Medications and Monitoring in Treatment of Nontuberculous Mycobacterial Pulmonary Disease

In the treatment of nontuberculous mycobacteria (NTM) lung disease, clinicians must consider potential toxicities that may occur as a result of prolonged exposure to a multidrug antibiotic regimen. Frequent clinical and microbiological monitoring is required to assess response and guide treatment duration. This article summarizes toxicity profiles of the antibiotics that are most frequently prescribed for the treatment of NTM lung disease. The role of therapeutic drug monitoring during use of amikacin and linezolid is discussed. The available evidence to guide frequency and extent of medication monitoring during NTM treatment is provided.

Development of prevalence and incidence of non-tuberculous mycobacteria in German laboratories from 2016 to 2020

Numbers of non-tuberculous mycobacteria (NTM) pulmonary diseases (PD) have been repeatedly reported as increasing over the last decades, particularly in Europe. Sound epidemiological data are however missing for most European regions. This study calculated prevalence and incidence of NTM recovered from patients' lungs in Germany, the largest Central European country, over a five-year period. It furthermore determined regional particularities of NTM species and results from susceptibility testing. 22 German NTM laboratories provided their mycobacteriological diagnostic data of 11,430 NTM isolates recovered from 5998 pulmonary patients representing 30% of all notified NTM-PD cases of Germany from 2016 to 2020. NTM incidence and prevalence were calculated for every study year. The presented epidemiological indicators are particularly reliant as TB surveillance data were used as a reference and TB notification reaches almost 100% in Germany. Laboratory incidence and prevalence of NTM recovered from respiratory samples ranged from 4.5-4.9 and from 5.3-5.8/100,000 for the population of Germany, respectively, and did not change over the five-year study period. Prevalence and incidence were stable also when stratifying for facultative pathogenic NTM, M. avium/intracellulare complex (MAIC), and M. abscessus/chelonae complex (MABSC). The proportion of NTM with drug susceptibility testing (DST) increased from 27.3% (2016) to 43.8% (2020). The unchanging laboratory NTM prevalence/incidence in Germany represents a "ceiling" of possible NTM-PD notification when diagnostic strategies do not change in the coming years. A notable increase in NTM-DST may indicate better notification of NTM-PD and/or awareness of new clinical guidelines but still remains below clinical needs.