Nontuberculous mycobacterial pulmonary disease: an integrated approach beyond antibiotics

Usual Interstitial Pneumonia Pattern and Mycobacteria Lung Diseases: A Case Series

BACKGROUND

Interstitial lung diseases (ILDs) are a heterogeneous group of conditions that can cause fibrosis of the lung interstitium, resulting in respiratory failure and death. Patients with an ILD, particularly idiopathic pulmonary fibrosis (IPF) or connective tissue disease-associated ILDs (CTD-ILDs), are prone to develop chronic pulmonary infections such as tuberculosis (TB) and non-tuberculous mycobacterial pulmonary disease (NTM-PD).

METHODS

This case series examines the management of three ILD patients with a usual interstitial pneumonia (UIP) pattern and concomitant NTM-PD or TB at National Institute for Infectious Diseases "Lazzaro Spallanzani" in Rome, Italy, over three years (2019-2022).

RESULTS AND CONCLUSIONS

Multi-disciplinary discussion (MDD) was crucial to define the therapeutic approach due to the increased risk of side effects and drug interactions. Our work underscored how a comprehensive diagnostic evaluation, enriched by MDD, is useful for optimizing the management and reducing drug-related adverse effects and interactions in ILD patients with cavitary lesions.

Treatment of nontuberculous mycobacterial pulmonary disease requires a stepwise and multidisciplinary approach

INTRODUCTION

Nontuberculous mycobacterial pulmonary disease (NTM-PD) occurs in people with inborn or acquired susceptibility factors. Current treatment guideline recommendations include a watchful waiting strategy, antimycobacterial and surgical treatment, with a comprehensive assessment of clinical, microbiological, and radiological factors determining which approach is most suitable.

AREAS COVERED

Treatment outcomes in NTM-PD are unsatisfactory with culture conversion rates varying from 30 to 80% and recurrence rates up to 50%. Possible explanations include our insufficient knowledge and management of host susceptibility factors, poor guideline adherence by physicians, frequent adverse drug reactions demanding premature discontinuation, inadequate drug exposures due to both drug-drug interactions and inter-patient variability in pharmacokinetics, and a lack of pharmacokinetics/pharmacodynamics targets.

EXPERT OPINION

We describe a stepwise approach to NTM-PD treatment, complementing existing guidelines, including recommendations for a multidisciplinary assessment, classification of disease severity, personalized supportive care, antimycobacterial treatment, adjuvant surgery, and host-directed therapies. The recommendations are informed by PubMed literature and the authors' clinical expertise. Recognizing that our experience is shaped within a specialized reference clinic, we acknowledge that some of these recommendations may not be applicable in all settings.

Recent advances in immunopathogenesis and clinical practice: mastering the challenge-managing of non-tuberculous mycobacteria

Non-tuberculous mycobacteria (NTM) are widespread environmental pathogens that can lead to significant disease burden, particularly in immunocompromised individuals, but also in those with a normal immune system. The global incidence of NTM is increasing rapidly, with Mycobacterium avium complex (MAC) being one of the most common types. The immunopathogenesis of the MAC involves a complex interaction between the bacteria and the host immune system. MAC survives and replicates within macrophages by preventing the fusion of phagosomes and lysosomes. The mycobacteria can neutralize reactive oxygen and nitrogen species produced by the macrophages through their own enzymes. Additionally, MAC modulates cytokine production, allowing it to suppress or regulate the immune response. Diagnosing MAC infections can be challenging, and the effectiveness of available treatments may be limited due to MAC's unpredictable resistance to various antimycobacterial drugs in different regions. Treating MAC infection requires a collaborative approach involving different healthcare professionals and ensuring patient compliance. This review aims to shed light on the complexities of MAC infection treatment, discussing the challenges of MAC infection diagnosis, pharmacological considerations, such as drug regimens, drug monitoring, drug interactions, and the crucial role of a multidisciplinary healthcare team in achieving the best possible treatment outcomes for patients.

Stealth in non-tuberculous mycobacteria: clever challengers to the immune system

Non-tuberculous Mycobacteria (NTM) are found extensively in various environments, yet most are non-pathogenic. Only a limited number of these organisms can cause various infections, including those affecting the lungs, skin, and central nervous system, particularly when the host's autoimmune function is compromised. Among these, Non-tuberculous Mycobacteria Pulmonary Diseases (NTM-PD) are the most prevalent. Currently, there is a lack of effective treatments and preventive measures for NTM infections. This article aims to deepen the comprehension of the pathogenic mechanisms linked to NTM and to formulate new intervention strategies by synthesizing current research and detailing the different tactics used by NTM to avoid elimination by the host's immune response. These intricate mechanisms not only affect the innate immune response but also successfully oppose the adaptive immune response, establishing persistent infections within the host. This includes effects on the functions of macrophages, neutrophils, dendritic cells, and T lymphocytes, as well as modulation of cytokine production. The article particularly emphasizes the survival strategies of NTM within macrophages, such as inhibiting phagosome maturation and acidification, resisting intracellular killing mechanisms, and interfering with autophagy and cell death pathways. This review aims to deepen the understanding of NTM's immune evasion mechanisms, thereby facilitating efforts to inhibit its proliferation and spread within the host, ultimately providing new methods and strategies for NTM-related treatments.

Predictive risk factors of treatment-refractory Mycobacterium avium complex lung disease: a single-center retrospective cohort study

Background

Mycobacterium avium complex lung disease (MAC-LD) is a chronic, progressive, potentially life-threatening infection. Some cases are refractory to standard guideline-based therapy (GBT), and sputum cultures are persistently positive for acid-fast bacilli. Although an early identification of treatment-refractory MAC-LD is crucial, its risk factors remain unknown.

Objectives

We aimed to identify the risk factors for refractory MAC-LD in response to initial GBT.

Design

A retrospective single-center study was conducted involving consecutive patients with MAC-LD who were diagnosed between 2006 and 2024 and received initial GBT.

Methods

Refractory MAC-LD was defined as sputum culture positivity at least 6 months after the initial GBT. Prognostic factors were identified using Cox proportional hazards analysis, and risk factors for refractory MAC-LD were examined using logistic regression analysis.

Results

Of the 201 patients with definite MAC-LD, 35 (17.4%) had refractory MAC-LD. Patients with refractory MAC-LD had a significantly lower body mass index (BMI), more cavitary lesions on high-resolution computed tomography (HRCT), and higher mortality (log-rank test, p = 0.006) compared to those with non-refractory MAC-LD. A multivariate analysis adjusted for age and sex showed that refractory MAC-LD (adjusted hazard ratio (HR): 2.76; 95% confidence interval (CI): 1.10-6.95; p = 0.030) and cavitary lesions on HRCT (adjusted HR: 2.77; 95% CI: 1.34-5.70; p = 0.005) were significantly associated with all-cause mortality. In addition, a multivariate analysis revealed that lower BMI (odds ratio (OR): 0.68; 95% CI: 0.55-0.85; p < 0.001) and cavitary lesions on HRCT (OR: 2.52; 95% CI: 1.15-5.50; p = 0.020) were independent risk factors of refractory MAC-LD.

Conclusion

Low BMI and cavitary lesions on HRCT are risk factors for refractory MAC-LD.

Targeting neutrophil serine proteases in bronchiectasis

Persistent neutrophilic inflammation is a central feature in both the pathogenesis and progression of bronchiectasis. Neutrophils release neutrophil serine proteases (NSPs), such as neutrophil elastase (NE), cathepsin G and proteinase 3. When chronically high levels of free NSP activity exceed those of protective antiproteases, structural lung destruction, mucosal-related defects, further susceptibility to infection and worsening of clinical outcomes can occur. Despite the defined role of prolonged, high levels of NSPs in bronchiectasis, no drug that controls neutrophilic inflammation is licensed for the treatment of bronchiectasis. Previous methods of suppressing neutrophilic inflammation (such as direct inhibition of NE) have not been successful; however, an emerging therapy designed to address neutrophil-mediated pathology, inhibition of the cysteine protease cathepsin C (CatC, also known as dipeptidyl peptidase 1), is a promising approach to ameliorate neutrophilic inflammation, since this may reduce the activity of all NSPs implicated in bronchiectasis pathogenesis, and not just NE. Current data suggest that CatC inhibition may effectively restore the protease-antiprotease balance in bronchiectasis and improve disease outcomes as a result. Clinical trials for CatC inhibitors in bronchiectasis have reported positive phase III results. In this narrative review, we discuss the role of high NSP activity in bronchiectasis, and how this feature drives the associated morbidity and mortality seen in bronchiectasis. This review discusses therapeutic approaches aimed at treating neutrophilic inflammation in the bronchiectasis lung, summarising clinical trial outcomes and highlighting the need for more treatment strategies that effectively address chronic neutrophilic inflammation in bronchiectasis.

Increasing trends of non-tuberculous mycobacteria clinical isolates in Guangzhou, China

Non-tuberculous mycobacteria (NTM) are one of major public health concern. The current study aimed to find the prevalence trends of NTM in Guangzhou, China from January 2018 to December 2023. A total of 26,716 positive mycobacterial cultures were collected. Thirty-six specimens with incomplete personal information were excluded. The remaining 26,680 specimens were identified using a gene chip method. 16,709 isolates were Mycobacterium tuberculosis (MTB) (62.63 %), and 9,971 were NTM (37.37 %). 43.43 % (4,330/9,971) of NTM isolates were male, and 56.57 % (5,641/9,971) were female (χ2 = 24.36, P < 0.05), a male to female ratio of approximately 1:1.30. Infections in individuals with aged 40 years and above was higher (77.63 %) than below 40 years (22.37 %) (χ2 = 4.94, P = 0.026). The annual NTM isolation rates from 2018 to 2023 were 32.03 %, 34.00 %, 36.27 %, 38.58 %, 38.99 %, and 43.24 %, respectively, showing an increasing trend (χ2 for trend = 0.097, P < 0.05) (R = 0.097, P < 0.05). Out of 9,971 NTM isolates, 8,881 cases include only five common NTM species (MAC, M. abscessus/M. chelonae, M. kansasii, M. fortuitum, and M. gordonae). The overall NTM isolation rate was 37.37 %. The NTM isolation rate was significantly higher than the national average, showing an increasing trend over the last six years.

Nontuberculous Mycobacterial Pulmonary Disease: Patients, Principles, and Prospects

Nontuberculous mycobacterial pulmonary disease (NTM-PD) is increasing in incidence globally and challenging to manage. The 2020 multisociety treatment guideline and the 2022 consensus recommendations provide comprehensive evidence-based guides to manage pulmonary diseases caused by the most common NTM. However, with >190 different NTM species that may require different multidrug regimens for treatment, the breadth and complexity of NTM-PD remain daunting for both patients and clinicians. In this narrative review, we aim to distill this broad, complex field into principles applicable to most NTM species and highlight important nuances, specifically elaborating on the presentation, diagnosis, principles of patient-centered care, principles of pathogen-directed therapy, and prospects of NTM-PD.

Efficacy of an oscillating positive expiratory pressure device in patients with Mycobacterium avium complex pulmonary disease

Patients with Mycobacterium avium complex pulmonary disease (MAC-PD) often suffer from chronic symptoms such as sputum production, which reduces quality of life. Oscillatory positive expiratory pressure (OPEP) devices are used in physiotherapy to promote the clearance of respiratory secretions. We report two cases of improved lung function and improved scores on the Leicester Cough Questionnaire (LCQ) and the Breathlessness, Cough and Sputum Scale (BCSS) after the use of OPEP in patients with MAC-PD where treatment with guideline-based therapy, including amikacin liposome inhalation suspension, had proved ineffective for symptoms. Use of OPEP might maximize the efficacy of therapy and thereby improves outcomes in patients with MAC-PD. It is important to use both guideline-based therapy and OPEP, especially in patients whose health-related quality of life is affected by sputum symptoms. Further prospective studies are warranted to assess the benefit of adding OPEP to guidelines concerning therapy for patients with MAC-PD and sputum symptoms.

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.

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.

Advances in diagnosis and treatment of non-tuberculous mycobacterial lung disease

The prevalence of Non-tuberculous Mycobacterial Pulmonary Disease (NTM-PD) is increasing worldwide. The advancement in molecular diagnostic technology has greatly promoted the rapid diagnosis of NTM-PD clinically, and the pathogenic strains can be identified to the species level through molecular typing, which provides a reliable basis for treatment. In addition to the well-known PCR and mNGS methods, there are numerous alternative methods to identify NTM to the species level. The treatment of NTM-PD remains a challenging problem. Although clinical guidelines outline several treatment options for common NTM species infections, in most cases, the therapeutic outcomes of these drugs for NTM-PD often fall short of expectations. At present, the focus of research is to find more effective and more tolerable NTM-PD therapeutic drugs and regimens. In this paper, the latest diagnostic techniques, therapeutic drugs and methods, and prevention of NTM-PD are reviewed.

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.

Risk factor of non-tuberculous Mycobacterium infection in patients with rheumatoid arthritis and other autoimmune diseases receiving biologic agents: A multicenter retrospective study

BACKGROUND

Evidence regarding the association of the usage of biologic agents (Etanercept, Tocilizumab, adalimumab and so on), such as anti-tumor necrosis factor α, with the incidence and risk factors of non-tuberculous Mycobacteria (NTM) infection is limited. Therefore, this study aimed to investigate the incidence and risk factors of NTM and their associations with biologic agents' usage, and also investigated the potential of Mycobacterium avium complex (MAC) antibodies as a predictor of NTM infection development.

METHODS

This retrospective study included 672 patients with autoimmune diseases from four hospitals in Nagasaki, Japan, from January 1, 2011, to June 30, 2019, who fulfilled the inclusion criteria.

RESULTS

Of the 672 patients, 9 (1.3%) developed complicated NTM infection, including two with disseminated infection, after the introduction of biologic agents. Of the nine patients, two died due to NTM infection but none tested positive for MAC antibodies prior to initiation of biologic agents. The mortality rate was higher in patients complicated with NTM than without NTM (22.2% vs 2.6%, P = 0.024). The corticosteroids dosage at the time of initiating the biologic agents was significantly higher in the NTM group than in the non-NTM group (median, 17 mg vs 3 mg, P = 0.0038).

CONCLUSION

In the patients undergoing therapy with biologic agents, although NTM complication was rare, it could be fatal. In particular, for patients on a relatively high dose corticosteroids, careful observation is essential for identifying NTM complication, even if the MAC antibody test is negative.

Treatable traits and challenges in the clinical management of non-tuberculous mycobacteria lung disease in people with cystic fibrosis

INTRODUCTION

Over the last ten years an increasing prevalence and incidence of non-tuberculous mycobacteria (NTM) has been reported among patients with cystic fibrosis (CF) Viviani (J Cyst Fibros, 15(5):619-623, 2016). NTM pulmonary disease has been associated with negative clinical outcomes and often requires pharmacological treatment. Although specific guidelines help clinicians in the process of diagnosis and clinical management, the focus on the multidimensional assessment of concomitant problems is still scarce.

MAIN BODY

This review aims to identify the treatable traits of NTM pulmonary disease in people with CF and discuss the importance of a multidisciplinary approach in order to detect and manage all the clinical and behavioral aspects of the disease. The multidisciplinary complexity of NTM pulmonary disease in CF requires careful management of respiratory and extra-respiratory, including control of comorbidities, drug interactions and behavioral factors as adherence to therapies.

CONCLUSIONS

The treatable trait strategy can help to optimize clinical management through systematic assessment of all the aspects of the disease, providing a holistic treatment for such a multi-systemic and complex condition.

Low geriatric nutritional risk index as a poor prognostic biomarker for immune checkpoint inhibitor treatment in solid cancer

Objective

In this investigation, we focused on the geriatric nutritional risk index (GNRI), a comprehensive metric that takes into account the patient's ideal weight, actual weight, and serum albumin levels to measure malnutrition. Our primary objective was to examine the predictive value of GNRI-defined malnutrition in determining the response to immunotherapy among cancer patients.

Methods

Relevant articles for this study were systematically searched in PubMed, the Cochrane Library, EMBASE, and Google Scholar up to July 2023. Our analysis evaluated overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and disease control rate (DCR) as clinical outcomes.

Results

This analysis comprised a total of eleven articles encompassing 1,417 patients. The pooled results revealed that cancer patients with low GNRI levels exhibited shorter OS (HR: 2.64, 95% CI: 2.08-3.36, p < 0.001) and PFS (HR: 1.87, 95% CI: 1.46-2.41, p < 0.001), and lower ORR (OR: 0.46, 95% CI: 0.33-0.65, p < 0.001) and DCR (OR: 0.42, 95% CI: 0.29-0.61, p < 0.001). Sensitivity analyses confirmed that the above results were stable. Egger's and Begg's tests revealed that there was no publication bias in the above results.

Conclusion

Our results imply that the GNRI is a useful predictor of immunotherapy response in cancer patients.

Unveiling the Clinical Diversity in Nontuberculous Mycobacteria (NTM) Infections: A Comprehensive Review

Once considered rare, nontuberculous mycobacterial (NTM) infections have garnered increasing attention in recent years. This comprehensive review provides insights into the epidemiology, clinical diversity, diagnostic methods, treatment strategies, prevention, and emerging research trends in NTM infections. Key findings reveal the global prevalence of NTM infections, their diverse clinical presentations affecting respiratory and extra-pulmonary systems, and the diagnostic challenges addressed by advances in microbiological, radiological, and immunological methods. Treatment complexities, especially drug resistance and patient adherence, are discussed, along with the vulnerability of special populations. The importance of early detection and management is underscored. Prospects in NTM research, including genomics, diagnostics, drug development, and multidisciplinary approaches, promise to enhance our understanding and treatment of these infections. This review encapsulates the multifaceted nature of NTM infections, offering a valuable resource for clinicians, researchers, and public health professionals.

Risk factors for microbiological persistence after 6 months of treatment for Mycobacterium intracellulare and its impact on the drug-resistance profile

Patients with Mycobacterium intracellulare pulmonary disease are more likely to experience poor treatment outcomes if they have been observed with microbiological persistence after 6 months of treatment. This study aims to identify the risk factors for microbiological persistence and describe the changes in the minimum inhibitory concentration (MIC) during antimycobacterial treatment. This retrospective case-control study enrolled patients diagnosed with M. intracellulare pulmonary disease between April 2017 and September 2021 at Shanghai Pulmonary Hospital. Patients with positive cultures after 6 months of treatment (positive group) were matched by age and sex in a 1:1 ratio to patients with negative conversion (negative group). Totally, 46 pairs of patients were analyzed. Risk factors for microbiological persistence at month 6 were smoking, previous tuberculosis treatment, chronic lung diseases, a positive baseline acid-fast bacilli smear, and adverse drug reactions; the risk was reduced by a regimen containing ethambutol, ≥3 effective drugs, and a higher pre-treatment absolute lymphocyte count. Regarding the drug-resistance profile, the negative group had a higher proportion of susceptibility to clarithromycin (100.0% vs 84.8%, P = 0.012). Most isolates were susceptible or intermediate to amikacin in both groups (93.5% and 84.8%, respectively). Nine patients (16.4%, 9/55) had a change in the drug-resistance profile, including four who changed from clarithromycin susceptible to clarithromycin resistant, and the other three reversed. Two pairs of isolates had a change in resistance to amikacin. In conclusion, risk factors for microbiological persistence were identified, and the change in MIC values during antimycobacterial treatment indicated the need for monitoring to enable timely adjustment of the regimen.IMPORTANCENontuberculous mycobacteria pulmonary disease (NTM-PD) has been recognized as an important public health issue because of its increasing incidence globally, low cure rate, and high recurrence rate. NTM-PD has innate resistance to many first-line anti-tuberculous drugs, which limits the treatment options. Mycobacterium intracellulare is reportedly the most important pathogenic NTM and accounts for the highest proportion of NTM-PD in China. A previous study suggested that poor microbiological response after 6 months of treatment is predictive of treatment failure. The present study investigated the risk factors associated with persistent positive sputum cultures by treatment month 6 in patients with M. intracellulare pulmonary disease and the variation in minimum inhibitory concentration patterns in clinical settings. This information might help to identify patients at higher risk of treatment failure and enable the timely provision of necessary interventions.

Nontuberculous mycobacterial pulmonary disease in a patient with unilateral pulmonary artery agenesis: Case report

Nontuberculous mycobacteria (NTM) are ubiquitous organisms, but can cause a chronic pulmonary infection in some patients. Therefore, there could be host factors susceptible to this disease. A structural lung disease including damages of lungs caused by previous respiratory infection has been suggested as a host factor. Here we presented a case of NTM pulmonary disease which developed in a structural lung disease caused by a rare congenital lung disease. A 46-year-old male, was transferred to our hospital with an unexpandable lung after a closed thoracostomy due to spontaneous pneumothorax. His chest computed tomography showed an absence of left pulmonary artery at the time of admission. Mycobacterial culture in sputum, bronchial washing fluid, and pleural fluid showed the growth of NTM. Mycobacterium intracellulare was isolated from all positive cultures in the specimens. Combinations of drugs for M. intracellulare pulmonary disease including azithromycin, rifampin, and ethambutol were administered for 16 months. Amikacin intra venous treatment used for 6 months after treatment initiation. Culture conversion was achieved at 4 months of treatment. There was no evidence of recurrence of NTM pulmonary disease for 6 months after treatment. In conclusion, patients who have structural lung disease need to be careful monitoring about development of NTM pulmonary disease.

Clinical characteristics of nontuberculous mycobacterial disease in people living with HIV/AIDS in South Korea: A multi-center, retrospective study

With the introduction of combination antiretroviral therapy (cART), the prevalence of human immunodeficiency virus (HIV)-associated nontuberculous mycobacteria (NTM) disease has declined. However, NTM diseases still occur in people living with HIV/acquired immunodeficiency syndrome (AIDS) (PLWHA). We analysed the clinical and microbiological features of NTM diseases in PLWHA in South Korea. PLWHA who were diagnosed with NTM diseases between January 2000 and March 2021 were retrospectively enrolled from five different hospitals in South Korea. Data on baseline demographics, HIV status, CD4+ T cell counts, viral load, past and current cART regimens, isolated NTM species, results of antimicrobial susceptibility tests, treatment regimens, and outcomes were collected by reviewing medical records. A total of 34 cases of NTM in PLWHA were included. Pulmonary and extrapulmonary NTM diseases accounted for 58.8% (n = 20) and 41.2% (n = 14), respectively. The lymph node was the most common site of extrapulmonary NTM disease (64.3%). The age at the time of NTM disease diagnosis was younger in the extrapulmonary NTM group than in the pulmonary NTM group (37.0 vs. 49.0 years). Mean CD4+ T cell counts at the time of NTM disease diagnosis was 186.6 cells/μL (range: 1–1394). Nine patients (26.5%) had fully suppressed viral loads at the time of NTM disease diagnosis. Mycobacterium avium complex (MAC) was the most common species found, followed by M. intracellulare and M. kansasii. MAC isolates were all susceptible to clarithromycin, but the rates of non-susceptibility to moxifloxacin, linezolid, ethambutol, and rifampin were 75%, 37.5%, 12.5%, and 12.5%, respectively. The average duration of treatment was 17 months and the mortality rate was 8.8%. NTM diseases may occur in PLWHA, even with completely suppressed viral loads. The identified clinical features of NTM diseases are essential for its clinical management in South Korea.

Nontuberculous Mycobacteria: Ecology and Impact on Animal and Human Health

Nontuberculous mycobacteria (NTM) represent an important group of environmentally saprophytic and potentially pathogenic bacteria that can cause serious mycobacterioses in humans and animals. The sources of infections often remain undetected except for soil- or water-borne, water-washed, water-based, or water-related infections caused by groups of the Mycobacterium (M.) avium complex; M. fortuitum; and other NTM species, including M. marinum infection, known as fish tank granuloma, and M. ulcerans infection, which is described as a Buruli ulcer. NTM could be considered as water-borne, air-borne, and soil-borne pathogens (sapronoses). A lot of clinically relevant NTM species could be considered due to the enormity of published data on permanent, periodic, transient, and incidental sapronoses. Interest is currently increasing in mycobacterioses diagnosed in humans and husbandry animals (esp. pigs) caused by NTM species present in peat bogs, potting soil, garden peat, bat and bird guano, and other matrices used as garden fertilizers. NTM are present in dust particles and in water aerosols, which represent certain factors during aerogenous infection in immunosuppressed host organisms during hospitalization, speleotherapy, and leisure activities. For this Special Issue, a collection of articles providing a current view of the research on NTM-including the clinical relevance, therapy, prevention of mycobacterioses, epidemiology, and ecology-are addressed.

Clinical significance and safety of combined treatment with chemotherapy and pulmonary rehabilitation regarding health-related quality of life and physical function in nontuberculous mycobacterial pulmonary disease

BACKGROUND

In the treatment of patients with nontuberculous mycobacterial pulmonary disease (NTM-PD), pulmonary rehabilitation (PR) has been recommended as a non-pharmacological therapy. However, no study has validated the combination of chemotherapy and PR in this context. This study investigated the effect of chemotherapy and supervised PR on health-related quality of life (HRQoL) and physical function in NTM-PD patients.

METHODS

This prospective cohort study included patients diagnosed with NTM-PD who had a planned hospitalization of at least 3 weeks for chemotherapy and PR. HRQoL (Leicester Cough Questionnaire [LCQ] and chronic obstructive pulmonary disease assessment test [CAT]), physical function (incremental shuttle walk distance [ISWD], quadriceps force), and C-reactive protein levels were assessed before and after treatment, and the corresponding data were analyzed in conjunction with clinical data. The adverse events of PR were also investigated.

RESULTS

Forty-two patients who met the study criteria were included in the analysis. After treatment, all LCQ item scores, total CAT score and sub-item scores related to respiratory symptoms, ISWD, quadriceps force, and C-reactive protein levels were found to have improved significantly. In the chronic cough with excessive sputum production (CCS) group, the proportions of responders who showed improvements in LCQ and CAT scores and ISWD greater than the corresponding minimal clinically important difference were significantly greater than those in the non-CCS group. No PR-related adverse events were reported.

CONCLUSIONS

Combined treatment with chemotherapy and PR may improve HRQoL and physical function, and supervised PR can be provided safely.

Decreased incremental shuttle walk test distance characterized by fibrocavitary lesions in non-tuberculous mycobacterial pulmonary disease

BACKGROUND

Patients with non-tuberculous mycobacterial pulmonary disease (NTM-PD) have impaired exercise capacity, but the underlying factors are unknown. We investigated the characteristics of patients with NTM-PD and impaired exercise capacity.

METHODS

In total, 149 patients with NTM-PD participated in this study. Patients completed the incremental shuttle walk test (ISWT) to assess exercise capacity. Peripheral muscle strength and pulmonary function were also assessed. Radiological findings were classified into three phenotypes: non-cavitary nodular bronchiectatic (NC-NB) form, cavitary nodular bronchiectatic form, and fibrocavitary (FC) form.

RESULTS

The median ISWT distance (ISWD) and %ISWD were 450 meters and 88%. Participants were classified into three groups according to %ISWD, with %ISWD <60% as the severely decreased group, 60%-80% as the moderately decreased group, and >80% as the normal or mildly decreased group. In a comparison of %ISWD among phenotypes, FC form had significantly lower %ISWD than those with NC-NB form. In the severely decreased group, peripheral muscle strength and pulmonary function were significantly lower than the other two groups. From a radiological standpoint, significantly more patients had FC form in the group with severely decreased %ISWD.

CONCLUSIONS

Decreased ISWD is characterized by a deterioration in physical function and the presence of FC lesions in NTM-PD.

Prevalence of Latent Tuberculous Infection in Patients with Nontuberculous Mycobacterial Lung Disease and Colonization: A Prospective Study in An Intermediate Tuberculosis Burden Country

Background

Controlling latent tuberculosis infection (LTBI) is important in eliminating tuberculosis (TB); however, the prevalence of LTBI has rarely been studied in patients with nontuberculous mycobacterial (NTM) lung disease (LD) and colonization (LC).

Methods

We prospectively recruited subjects with NTM isolated from sputum mycobacterial cultures from December 2011 to June 2019. NTM-LD and NTM-LC were defined according to the American Thoracic Society guidelines. Patients with negative cultures were recruited as controls. Patients with a history of active TB or positive TB cultures were excluded. LTBI was confirmed using a QuantiFERON-TB Gold In-tube test. The prevalence and factors associated with LTBI were analyzed.

Results

A total of 406 participants were enrolled, including 171 in the NTM-LD group, 153 in the NTM-LC group, and 82 in the control group. The prevalence of LTBI was higher in the NTM-LD and NTM-LC groups than in the controls (21.6%, 20.9%, and 6.1%; P = .006). Multivariable analysis showed that old age (adjusted odds ratio [aOR], 1.021, per year increment; P = .042), NTM-LD (aOR, 4.030; P = .005), NTM-LC (aOR, 3.610; P = .011, compared with the controls), and pulmonary cavitary lesions (aOR, 3.393; P = .034) were independently associated with LTBI.

Conclusions

The prevalence of LTBI was higher in the patients with NTM-LD and NTM-LC than in the controls. Old age, pulmonary cavitation, and NTM isolated from sputum were associated with a higher risk of LTBI.

Association of the Geriatric Nutritional Risk Index With the Survival of Patients With Non-Small Cell Lung Cancer After Nivolumab Therapy

The nutritional status has the potential to affect cancer immunity. We evaluated the relationship between the nutritional status and the efficacy of nivolumab in patients with non-small cell lung cancer (NSCLC). This study was a post hoc analysis of a prospective, multicenter cohort study conducted at 14 institutions in Japan between July 2016 and December 2018. The Geriatric Nutritional Risk Index (GNRI), calculated from body weight and serum albumin, was evaluated in 158 patients with NSCLC who received nivolumab. GNRI was graded as low, moderate, and high. Low GNRI was associated with significantly shorter progression-free survival [median, 1.9 mo; 95% confidence interval (CI)=0.6-3.3 mo] than moderate (median, 4.0 mo; 95% CI=2.3-5.8 mo; P=0.017) and high GNRI (median, 3.0 mo; 95% CI=1.9-7.2 mo; P=0.014). Low GNRI was also linked to significantly shorter overall survival (OS) (median, 7.8 mo; 95% CI=2.6-12.0 mo) than moderate (median, 13.0 mo; 95% CI=9.6-15.2 mo; P=0.006) and high GNRI (median, 20.6 mo; 95% CI=15.6 mo-not reached; P<0.001). High GNRI was associated with significantly longer OS than moderate GNRI (P=0.015). In multivariate Cox proportional hazard analyses, increased GNRI was predictive of longer progression-free survival and OS, similarly as tumor programmed cell death-ligand 1 expression. In patients with NSCLC receiving nivolumab. GNRI was predictive of survival and may be useful for predicting the efficacy of immune checkpoint inhibitor therapy.

Association of the Geriatric Nutritional Risk Index with the survival of patients with non-small-cell lung cancer after platinum-based chemotherapy

Background

The nutritional status can potentially affect the efficacy of cancer therapy. The Geriatric Nutritional Risk Index (GNRI), a simple index for evaluating nutritional status calculated from body weight and serum albumin levels, has been reported to be associated with the prognosis of various diseases. However, the relationships between GNRI and the efficacy of platinum-based chemotherapy in patients with non-small-cell lung cancer (NSCLC) are unknown.

Methods

The pretreatment levels of GNRI were retrospectively evaluated in 148 chemo-naïve patients with advanced NSCLC who received first-line platinum-based chemotherapy and scored as low or high.

Results

Patients with a high GNRI had a significantly higher overall response rate (ORR; 44.5% [95% confidence interval {CI} = 35.6%–53.9%] vs. 15.8% [95% CI = 7.4%–30.4%, p = 0.002), longer median progression-free survival (PFS; 6.3 months [95% CI = 5.6–7.2 months] vs. 3.8 months [95% CI = 2.5–4.7 months], p < 0.001), and longer median overall survival (OS; 22.8 months [95% CI = 16.7–27.2 months] vs. 8.5 months [95% CI = 5.4–16.0 months], p < 0.001) than those with low GNRI. High GNRI was independently predictive of better ORR in multivariate logistic regression analysis and longer PFS and OS in multivariate Cox proportional hazard analyses. In 71 patients who received second-line non-platinum chemotherapy, patients with high GNRI exhibited significantly longer PFS and OS than those with low GNRI (both p < 0.001).

Conclusions

GNRI was predictive of prolonged survival in patients with NSCLC who received first-line platinum-based chemotherapy and second-line non-platinum chemotherapy. Assessment of the nutritional status may be useful for predicting the efficacy of chemotherapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01782-2.

Anxiety and depression in patients with nontuberculous mycobacterial pulmonary disease: a prospective cohort study in South Korea

BACKGROUND

The mental health of patients with nontuberculous mycobacterial pulmonary disease (NTM-PD) has been underestimated.

RESEARCH QUESTION

What is the prevalence of, associated factors for, and clinical impact of anxiety and depression in patients with NTM-PD?

STUDY DESIGN AND METHODS

Among the patients diagnosed with NTM-PD between July 1, 2011 and December 31, 2019, who were a part of Seoul National University Hospital's prospective cohort, we included those who completed the Hospital Anxiety and Depression Scale (HADS) at least twice. Multivariable logistic regression analysis was used to identify the factors associated with anxiety and depression. Multilevel mixed-effects regression was used to analyze the HADS scores' longitudinal trends.

RESULTS

A total of 368 patients were included in this study, including 84 (22.8%) with anxiety (HADS-A score ≥8) and 83 (22.5%) with depression (HADS-D score ≥8). The presence of cough (adjusted odds ratio [aOR] 2.01, 95% confidence interval [CI] 1.19-3.39) and febrile sensation (aOR 4.45, 95% CI 2.13-9.30) were associated with anxiety, whereas dyspnea (aOR 4.13, 95% CI 1.38-12.37) and febrile sensation (aOR 2.91, 95% CI 1.38-6.13) were associated with depression. Although the HADS scores of patients with anxiety or depression at the time of enrollment and throughout the follow-up period were higher than those without, these scores declined significantly within one year after enrollment. Patients with anxiety (P=0.006) or depression (P=0.004) received antibiotic treatment more frequently than those without. Treatment outcomes did not differ depending on the initial anxiety or depression status.

INTERPRETATION

Anxiety and depression were common in patients with NTM-PD and were associated with patient-reported symptoms. While these persisted over time, the treatment outcomes did not differ.