Variable agreement among experts regarding Mycobacterium avium complex lung disease

Pulmonary Nontuberculous Mycobacterial Infection in Infants: A Systematic Review

Limited information and literature exist examining pulmonary infections caused by nontuberculous mycobacterial specifically in an infant population. The objective of our study was to summarize clinical characteristics and outcomes of infant patients with nontuberculous mycobacterial pulmonary infection via systematic literature review to identify common diagnostic and treatment regimens for this infection in infants. A search of MEDLINE and PubMed databases in October 2019 using MeSH search terms “infant,” “NTM,” “pulmonary,” and “Mycobacterium abscessus” yielded 139 articles. Inclusion criteria were i) English-language studies including cases and case series with ii) established nontuberculous mycobacterial pulmonary infection in iii) a patient population of infants no older than 24 months. Patients with cystic fibrosis and any study which did not contain relevant information such as infection and age were excluded. This yielded data on 37 patients extracted from 28 studies analyzed. The most common strain was Mycobacterium avium complex, isolated in 56.8% of patient diagnoses. Bronchoscopy/thoracoscopy with a subsequent culture were the most common diagnostic techniques, utilized in 64.9% of cases. Drug therapeutic treatment was utilized in 86% of cases, with a median of three drugs administered. Notable limitations of this study are the small sample size and its retrospective nature, which relies on information reported in previous case studies. Although there is limited formal clinician consensus on the treatment of NTM pulmonary infection and how it may differ in an infant population, our findings indicate an informal consensus typically involving diagnostic lung specimen culture and antibiotic therapy.

Guidelines in Gastroenterology: Careful Interpretation Is Essential

Introduction

Clinical practice guidelines (CPG) contain recommendations that aim to guide physicians in the diagnosis of and therapeutic approach toward patients affected by gastrointestinal (GI) pathologies. These CPG systematically combine scientific evidence and clinical judgment, culminating in recommendations that have been shown to improve patient care.

Material and Methods

European and North American guidelines published in the area of gastroenterology in 2018 and 2019 were considered for inclusion. To standardize the results, only guidelines that used GRADE as an evidence system were included. Thus, in the end, 1,233 recommendations from 29 guidelines published between 2018 and 2019 were analyzed.

Results

Of the 1,233 recommendations collected, 324 (26.3%) had a low level of evidence and 127 (10.3%) had a very low level of evidence, indicating little evidence or expert opinion. Of the 29 publications analyzed, 14 (48.3%) did not present any recommendation with a high level of evidence. Regarding the 1,233 individual recommendations expressed in these 29 publications, only 336 (27.25%) assumed a high level of evidence, with 277 (82.44%) referring to liver pathology. Of the recommendations evaluated, 77 were from North American societies and the remaining 1,156 were European recommendations. In relation to the first group, only 3 (3.9%) had a high level of evidence belonging to the Guidelines for Sedation and Anesthesia in GI Endoscopy.

Conclusions

More than 25% of all recommendations currently accepted to guide patients with gastroenterological disorders are based on low-quality evidence or expert opinion. Thus, these documents should guide our performance, but clinical sense and multidisciplinarity must not be overlooked in dubious cases and with weak scientific evidence. Research should focus on the development of randomized controlled trials and systematic reviews to improve the evidence supporting the guidelines that guide clinical practice.

Management of Drug Toxicity in Mycobacterium avium Complex Pulmonary Disease: An Expert Panel Survey

Adverse events are frequent in nontuberculous mycobacteria pulmonary disease treatment, but evidence to support their management is scarce. An expert panel survey on management of adverse events shows consistent opinions on management of hepatoxicity, ocular toxicity, ototoxicity, tinnitus, and gastrointestinal upset. These opinions can provide assistance in individual patient management decisions.

Scientific evidence underlying the American College of Gastroenterology's clinical practice guidelines

BACKGROUND

Clinical practice guidelines contain recommendations for physicians to determine the most appropriate care for patients. These guidelines systematically combine scientific evidence and clinical judgment, culminating in recommendations intended to optimize patient care. The recommendations in CPGs are supported by evidence which varies in quality. We aim to survey the clinical practice guidelines created by the American College of Gastroenterology, report the level of evidence supporting their recommendations, and identify areas where evidence can be improved with additional research.

METHODS

We extracted 1328 recommendations from 39 clinical practice guidelines published by the American College of Gastroenterology. Several of the clinical practice guidelines used the differing classifications of evidence for their recommendations. To standardize our results, we devised a uniform system for evidence.

RESULTS

A total of 39 clinical practice guidelines were surveyed in our study. Together they account for 1328 recommendations. 693 (52.2%) of the recommendations were based on low evidence, indicating poor evidence or expert opinion. Among individual guidelines, 13/39 (33.3%) had no recommendations based on high evidence.

CONCLUSION

Very few recommendations made by the American College of Gastroenterology are supported by high levels of evidence. More than half of all recommendations made by the American College of Gastroenterology are based on low-quality evidence or expert opinion.

Respiratory infections due to nontuberculous mycobacterias

The most common infections caused by nontuberculous mycobacteria (NTM) are lung infections. The microorganisms causing these infections most frequently are Mycobacterium avium complex, Mycobacterium kansasii and Mycobacterium abscessus complex. Their incidence has increased in the last three decades. After identifying an NTM in the respiratory tract, clinical and radiological aspects must be considered to determine if isolations are clinically relevant. Predisposing conditions that could contribute to infection must also be investigated. Pulmonary disease due to NTM is presented in three clinical forms: a) pneumonitis due to hypersensitivity; b) fibrocavitary form; and c) nodular-bronchiectasic. The diagnosis of respiratory disease due to NTM does not make it obligatory to immediately initiate treatment. Before initiating the latter, other factors must be considered, such as age, comorbidities, life expectancy, due to the prolonged nature of treatments, with potential side effects and, in many cases, only a slight response to the treatment.

Factors which influence treatment initiation for pulmonary non-tuberculous mycobacterium infection in HIV negative patients; a multicentre observational study

BACKGROUND

Clinical, radiological and microbiological criteria inform diagnosis of pulmonary Non-Tuberculous Mycobacteria (NTM) disease and treatment decisions. This multicentre, review aims to characterise NTM disease meeting ATS/IDSA criteria and define factors associated with initiation of treatment.

METHODS

Sputum samples growing NTM from 5 London hospitals between 2010 and 2014 were identified. Data for HIV-negative individuals meeting ATS/IDSA guidelines for pulmonary NTM disease were extracted. Associations between clinical variables and treatment decision were investigated using Chi-squared, Fishers-exact or Mann Whitney tests. Factors associated with treatment in univariate analysis (p < 0.150) were included in a multivariate logistic regression model.

RESULTS

NTM were identified from 817 individuals' sputum samples. 108 met ATS/IDSA criteria. 42/108 (39%) were initiated on treatment. Median age was 68 (56-78) in the cohort. On multivariate analysis, factors significantly associated with treatment of pulmonary NTM infection were: Cavitation on HRCT (OR: 6.49; 95% CI: 2.36-17.81), presenting with night sweats (OR 4.18; 95% CI: 1.08-16.13), and presenting with weight loss (OR 3.02; 95% CI: 1.15-7.93). Of those treated, 18(43%) have completed treatment, 9(21%) remain on treatment, 10(24%) stopped due to side effects, 5(12%) died during treatment. Mortality was 31% (n = 13) in treated versus 21% (n = 14) in the non-treated cohort. Subgroup analysis of individual NTM species did not observe any differences in treatment initiation or outcomes between groups.

DISCUSSION

Decision to treat pulmonary NTM infection requires clinical judgement when interpreting clinical guidelines. Factors independently associated with decision to treat in this HIV-negative cohort include cavitation on HRCT and presenting with night sweats or weight loss.

Diagnosis and Treatment of Nontuberculous Mycobacterial Lung Disease: Clinicians' Perspectives

Nontuberculous mycobacteria (NTM) are emerging pathogens that affect both immunocompromised and immunocompetent patients. The incidence and prevalence of NTM lung disease are increasing worldwide and rapidly becoming a major public health problem. For the diagnosis of NTM lung disease, patients suspected to have NTM lung disease are required to meet all clinical and microbiologic criteria. The development of molecular methods allows the characterization of new species and NTM identification at a subspecies level. Even after the identification of NTM species from respiratory specimens, clinicians should consider the clinical significance of such findings. Besides the limited options, treatment is lengthy and varies by species, and therefore a challenge. Treatment may be complicated by potential toxicity with discouraging outcomes. The decision to start treatment for NTM lung disease is not easy and requires careful individualized analysis of risks and benefits. Clinicians should be alert to those unique aspects of NTM lung disease concerning diagnosis with advanced molecular methods and treatment with limited options. Current recommendations and recent advances for diagnosis and treatment of NTM lung disease are summarized in this article.

Antibiotic treatment for nontuberculous mycobacterial lung disease

Pulmonary infections are the most frequent diseases caused by nontuberculous mycobacteria (NTM). Common causative organisms of pulmonary infection are slowly growing mycobacteria including Mycobacterium avium complex and Mycobacterium kansasii, and rapidly growing mycobacteria including Mycobacterium abscessus complex. Clinical concern has been raised over the increasing incidence of NTM lung disease combined with the poor treatment outcomes of these chronic infectious diseases. Since treatment guidelines of the American Thoracic Society/Infectious Disease Society of America were published in 2007 there have been continuous efforts to improve the outcomes of NTM lung disease, albeit slowly and with limitations. Here, we focus on recent advances in the antibiotic treatment of NTM lung disease.

Health-related quality of life, comorbidities and mortality in pulmonary nontuberculous mycobacterial infections: A systematic review

Nontuberculous mycobacterial (NTM) infections are increasing in disease frequency worldwide. This systematic review examines health-related quality of life (HRQOL), comorbidities and mortality associated with pulmonary NTM disease. We searched MEDLINE, EMBASE, CINAHL, Scopus Life Sciences, conference proceedings and Google (earliest date available to February 2015) for primary studies. Eligible studies compared populations with and without pulmonary NTM disease in high-income jurisdictions. We excluded studies on HIV/AIDS. All languages were accepted. Two reviewers followed MOOSE and PRISMA reporting guidelines and independently appraised quality using STROBE. All studies were summarized qualitatively regardless of quality. Of 3193 citations screened, we included 17 studies mostly from Taiwan (n = 5) and the USA (n = 4). Two studies assessed HRQOL; one assessed comorbidities, 11 assessed mortality, and three assessed multiple outcomes. Populations with pulmonary NTM reported significantly worse or similar HRQOL than the general population, depending on the instruments used. Some suggested greater prevalence of having bronchiectasis (n = 2) and greater risk of developing pulmonary tuberculosis (n = 1). Most (n = 7) suggested no difference in mortality, although only one was age-matched and gender-matched to the general population. Four suggested NTM populations had higher mortality-two of which compared with the general population and were deemed of high quality, while two compared with non-NTM patients from hospital. High clinical heterogeneity in study design may explain discordant results. Bias assessments and controlling for confounding were carried out poorly. No consistent trends were observed although there is suggestion of an increased health burden from respiratory diseases and increased mortality associated with pulmonary NTM disease.

Update on pulmonary disease due to non-tuberculous mycobacteria

Non-tuberculous mycobacteria (NTM) are emerging worldwide as significant causes of chronic pulmonary infection, posing a number of challenges for both clinicians and researchers. While a number of studies worldwide have described an increasing prevalence of NTM pulmonary disease over time, population-based data are relatively sparse and subject to ascertainment bias. Furthermore, the disease is geographically heterogeneous. While some species are commonly implicated worldwide (Mycobacterium avium complex, Mycobacterium abscessus), others (e.g., Mycobacterium malmoense, Mycobacterium xenopi) are regionally important. Thoracic computed tomography, microbiological testing with identification to the species level, and local epidemiology must all be taken into account to accurately diagnose NTM pulmonary disease. A diagnosis of NTM pulmonary disease does not necessarily imply that treatment is required; a patient-centered approach is essential. When treatment is required, multidrug therapy based on appropriate susceptibility testing for the species in question should be used. New diagnostic and therapeutic modalities are needed to optimize the management of these complicated infections.

Semiquantitative Culture Analysis during Therapy for Mycobacterium avium Complex Lung Disease

RATIONALE

Microbiologically based criteria such as sputum culture conversion to negative have traditionally been used to define treatment success for mycobacterial diseases. There are, however, limited data regarding whether nontuberculous mycobacterial sputum culture conversion or semiquantitative culture analysis correlates with subjective or nonmicrobiologic objective indices of treatment response.

OBJECTIVES

To determine whether a semiquantitative mycobacterial culture scale correlated with clinical disease status and was predictive of long-term sputum mycobacterial culture conversion to negative in a cohort of patients with nodular/bronchiectatic Mycobacterium avium complex lung disease undergoing therapy.

METHODS

One hundred and eighty patients undergoing standard macrolide-based therapy for M. avium complex lung disease were monitored at standard frequent intervals with symptomatic, radiographic, and microbiologic data collected, including semiquantitative mycobacterial culture analysis. Analyses were used to evaluate clinical and microbiologic predictors of long-term sputum conversion to culture negative.

MEASUREMENTS AND MAIN RESULTS

After 12 months of therapy, 148 (82%) patients had sputum conversion to culture negative. Baseline semiquantitative sputum culture scores did not differ between patients with sputum conversion and those without. The change in sputum culture semiquantitative score from baseline to Month 3 was highly predictive of subsequent sputum long-term conversion status indicative of treatment success, as was improvement in cough, and especially early radiographic improvement.

CONCLUSIONS

Early semiquantitative sputum agar plate culture results can be used to predict symptomatic and radiographic improvement as well as long-term sputum culture conversion to negative in this population. We suggest that semiquantitative sputum culture scores can be a useful tool for evaluating new nontuberculous mycobacterial lung disease therapies.