Effect of time,temperature and pH on Mycobacterium tuberculosis culture positivity of gastric aspirate: An experimental study

BackgroundThe culture of gastric aspirate (GA) has been used for bacteriological confirmation of pulmonary tuberculosis in children and patients who are unable to expectorate. Sodium bicarbonate neutralization of gastric aspirates is commonly recommended to increase culture positivity. We aim to study Mycobacterium tuberculosis (MTB) culture positivity of GA collected from confirmed case of pulmonary tuberculosis after storing it at different temperature, pH & time.MethodsGA specimens from 865 patients of either sex predominately non-expectorating children/adults with suspected pulmonary TB were collected. Gastric lavage was performed in the morning after an overnight fasting (at least 6hrs fasting). The GA specimens were tested by CBNAAT (GeneXpert) and AFB microscopy & those who were positive on CBNAAT were further processed with MTB culture on Growth Indicator Tube (MGIT™) culture. pH neutralized and non-neutralized CBNAAT positive GA specimens were culture within 2 hours of collection and 24 hours after storage at 4 °C & room temperature.ResultsMTB was detected in 6.8% of collected GA specimens by CBNAAT. Culture positivity of neutralized GA specimens when processed within 2 hours of collection, was higher compared to paired non-neutralized GA specimens. Neutralized GA specimens had higher contamination rate than non-neutralized GA specimens. Storage of GA specimens at $Deg C had better culture yield than those stored at room temperature.ConclusionEarly neutralization of acid in Gastric aspirate (GA) is essential for better culture positivity of M. tuberculosis (MTB). If there is a delay in processing GA, it should be kept at 4 °C after neutralization; however, positivity decreases with time.     

Vessel invasion as a predictive factor for recurrence after surgery in stage I lung adenocarcinoma

BackgroundPatients with early-stage lung cancer who underwent R0 resection often encounter disease recurrence, especially during the early phase; thus, it is deemed vital to determine the predictive factors for recurrence after surgery. In this study, we aimed to identify the independent variables associated with recurrence after complete surgical resection of pathological stage I lung adenocarcinoma.MethodsWe retrospectively reviewed the medical records of 169 patients who underwent pulmonary resection for primary lung adenocarcinoma pathological stage I with curative intent lung cancer surgery from 2015 to December 2018 at our institution for information on the recurrence of the disease.ResultsPer the multivariate analysis, the presence of micropapillary pattern and vessel invasion were found to be independent predictors of disease recurrence after surgery (odds ratio [OR]: 9.36, 95% confidence interval [CI]: 2.42–36.2, P = 0.0012; and OR: 4.50, 95% CI: 1.52–13.4, P = 0.0068, respectively). Vessel invasion was also found to be an independent predictor of disease recurrence after surgery within a year (OR 11.4, 95% CI 3.08–42.5, P = 0.0003).ConclusionsThe presence of vessel invasion may help in distinguishing patients with the highest risk of early-phase disease recurrence after surgery. Patients with stage I adenocarcinoma with vessel invasion should undergo intensive surveillance after surgery.     

Prediction of the duration needed to achieve culture negativity in patients with active pulmonary tuberculosis using convolutional neural networks and chest radiography

BackgroundWe aimed to predict the duration needed to achieve culture negativity in patients with active pulmonary tuberculosis using convolutional neural networks (CNNs) and chest radiography.MethodsMedical records were searched for eligible patients with culture-confirmed active pulmonary tuberculosis. The eligible patients were randomly assigned to the training dataset group (N = 180) and the validation dataset group (N = 59). Posteroanterior X-ray radiographs in the standing position were obtained at diagnosis. The image data were augmented by a factor of 10 by randomly shifting and rotating the original image. Thus, 1800 images (112 × 112 pixels, 8-bit grayscale) from 180 patients in the training dataset group were used for training the CNN model. The model performance was evaluated on the validation dataset.ResultsThe values predicted by the CNN model were significantly associated with the actual values (Pearson's correlation coefficient 0.392, p = 0.002). The mean absolute error was 18.0. The visualization of the layer outputs suggested that the CNN model recognized some of the chest radiographic findings that were useful in predicting the duration needed to achieve culture negativity.ConclusionsThe CNN model was useful for predicting the duration needed to achieve culture negativity in active pulmonary tuberculosis, although the accuracy was unsatisfactory. This study suggests that chest radiography findings are as important as other clinical factors for prediction and could be learned by the machine.     

Risk factors of tuberculosis in Mizoram: First report of the possible role of water source

BackgroundVarious risk factors of tuberculosis have been studied across the globe, but these may be altered over time and can be specific to geographical regions and there is not much information available from Northeastern region of India. This study aims to investigate the various risk factors of tuberculosis and analyze the presence of any less-established risk factors.MethodsA total of 400 TB cases and 840 healthy controls were interviewed from December 2017 - June 2020. Logistic regression model was used to analyze associated risk factors. Patients were categorized into pulmonary and extrapulmonary TB.ResultsClinical presentation such as fever, cough, weight loss, chest pain and night sweats were more prominent among pulmonary TB patients. The most common mode of diagnosis among pulmonary and extrapulmonary TB were GeneXpert and X-ray, respectively. Tuberculosis was found to be strongly prevalent among patients from lower socio-economic status, less educated, unemployed and improper housing condition. Other risk factors associated were alcohol consumption, neighbours with TB, travel history, no BCG vaccine, mass gathering, and non-ideal weight. An interesting less-established risk factor that demands attention is the source of water supply (p-0.017, OR-2.313, CI: 1.160–4.613), which was significant in this study.ConclusionOur data suggests that apart from all the well-established risk factors for TB, water supply might play a crucial role towards the transmission of TB, since proper hospital waste water treatment is yet to be adopted in Mizoram, Northeast India. From a public health standpoint, this highlights the need for further research in this area.     

Interleukin-37 gene polymorphism and susceptibility to pulmonary tuberculosis among Iraqi patients

BackgroundControl of tuberculosis (TB) depends on a balance between host's immune factors and bacterial evasion strategies. Interleukin-37 (IL-37) is among the immunomodulatory factors that have been proposed to influence susceptibility to tuberculosis.MethodsA case–control study was conducted on 105 patients with pulmonary TB (37 active, 41 multi-drug resistant and 27 relapse) and 79 healthy controls to determine serum levels and single nucleotide polymorphisms (SNPs) of IL-37. The IL-37 level was assessed with an enzyme-linked immunosorbent kit, while DNA-sequencing was used to detect SNPs in the promoter region of IL37 gene.Results: Median level of IL-37 was markedly increased in serum of TB patients compared to controls (325.0 vs. 169.1 pg/mL; p < 0.001). This increase was universally determined in subgroups of patients distributed according to gender, age groups, and clinical type of disease, while no significant differences were found between the subgroups in patients or controls. Analysis of receiver operating characteristic curve confirmed these findings and IL-37 occupied a very good area under the curve, which was 0.816 (95% CI = 0.744–0.888; p < 0.001). At a cut-off value of 185.6 pg/mL, the sensitivity and specificity of IL-37 were 81.0 and 82.3%, respectively. Of the nine detected SNPs (rs2466449 G/A, rs2466450 A/G, rs2723168 G/A, rs3811042 G/A, rs3811045 T/C, rs3811046 G/T, rs3811047 A/G, rs3811048 G/A and rs200782323 G/A), only rs3811048 showed a significant association with TB; the G allele showed a significantly decreased frequency in TB patients compared to controls (25.2 vs. 44.9%; OR = 0.41; p < 0.001). It was possible to assign five haplotypes, and three showed significant differences between patients and controls. Frequency of haplotype A-A-G-A-C-T-G-A-G (0.331 vs. 0.213; OR = 2.10; p = 0.015) was significantly increased in TB patients compared to controls. On the contrary, frequencies of haplotypes A-A-G-A-C-T-G-G-G (0.029 vs. 0.116; OR = 0.24; p = 0.01) and A-A-G-G-T-G-A-G-G (0.140 vs. 0.275; OR = 0.45; p = 0.015) were significantly decreased in patients.ConclusionsIL-37 was up-regulated in the serum of TB patients irrespective of their gender, age or clinical type of disease. SNPs in the promoter region of IL37 gene were proposed to be associated with susceptibility to TB.     

Cellular senescence—an aging hallmark in chronic obstructive pulmonary disease pathogenesis

Chronic obstructive pulmonary disease (COPD),¹ a representative aging-related pulmonary disorder, is mainly caused by cigarette smoke (CS) exposure. Age is one of the most important risk factors for COPD development, and increased cellular senescence in tissues and organs is a component of aging. CS exposure can induce cellular senescence, as characterized by irreversible growth arrest and aberrant cytokine secretion of the senescence-associated secretory phenotype; thus, accumulation of senescent cells is widely implicated in COPD pathogenesis. CS-induced oxidative modifications to cellular components may be causally linked to accelerated cellular senescence, especially during accumulation of damaged macromolecules. Autophagy is a conserved mechanism whereby cytoplasmic components are sent for lysosomal degradation to maintain proteostasis. Autophagy diminishes with age, and loss of proteostasis is one of the hallmarks of aging. We have reported the involvement of insufficient autophagy in regulating CS-induced cellular senescence with respect to COPD pathogenesis. However, the role of autophagy in COPD pathogenesis can vary based on levels of cell stress and type of selective autophagy because excessive activation of autophagy can be responsible for inducing regulated cell death. Senotherapies targeting cellular senescence may be effective COPD treatments. Autophagy activation could be a promising sonotherapeutic approach, but the optimal modality of autophagy activation should be examined in future studies.     

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

BackgroundIn 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.MethodsThis 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.ResultsForty-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.ConclusionsCombined treatment with chemotherapy and PR may improve HRQoL and physical function, and supervised PR can be provided safely.     

High-Risk Pulmonary Embolism During Labor: JACC Patient Care Pathways

While in labor, a 37-year-old woman developed acute dyspnea, hypoxemia, and tachycardia. Transthoracic echocardiography demonstrated severe right ventricular dilation and dysfunction, raising the suspicion of acute pulmonary embolism. The patient indeed had bilateral pulmonary embolism, necessitating percutaneous thrombectomy. Her course was complicated by another saddle pulmonary embolus, heparin-induced thrombocytopenia, and COVID-19 infection. This clinical case illustrates the importance of prompt diagnosis of acute pulmonary embolism in a peripartum female patient, the multidisciplinary approach of management, and how to approach clinical complications such as heparin-induced thrombocytopenia. Furthermore, long-term management in acute pulmonary embolism is presented.     

Prevalence of pulmonary embolism in patients with obstructive sleep apnea and chronic obstructive pulmonary disease: The overlap syndrome

ObjectiveGrowing evidence indicates that both obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) may be closely associated with the prevalence of pulmonary embolism (PE). However, the relationship of overlap syndrome (OS) (coexistence of OSA and COPD) with PE is unclear. The purpose of this study was to investigate whether OS were associated with increased PE prevalence.MethodsWe performed a retrospective chart review of patients who underwent sleep study at Beijing An Zhen Hospital from 2011 to 2014. The association of OS with PE prevalence was estimated by using logistic regression models.ResultsIn contrast to control patients (neither OSA nor COPD), those subjects with OS had higher odds of PE (OR9.61; 95%CI 4.02–21.31, p < 0.001) with significance persisting after adjusting for covariates (OR 5.66; 95%CI 1.80–16.18, p = 0.004). Meanwhile, patients with OS compared with those with isolated OSA also had significantly higher odds of PE in univariate (OR 4.79; 95%CI 2.04–10.33, p = 0.0007) and adjusted models (OR 3.89; 95%CI 1.27–10.68, p = 0.019). In subgroup analysis, patients with OS had higher odds of PE than control group among male subjects (OR 8.12, 95%CI1.86–31.87, p = 0.007) and patients ≥ 58years (OR 5.50, 95%CI 1.51–18.14, p = 0.012) in multivariable models. Percentage of total sleep time with saturation lower than 90% (T90) ≥ 2.6% was significantly associated with prevalence of PE (OR 4.72, 95%CI1.34–19.83, p = 0.015) in subgroup of patients older than 58.ConclusionsOS is independently associated with PE prevalence. Longitudinal studies are needed to better understand the relationship with incident PE.     

Lower dose of ethambutol may reduce ocular toxicity without radiological deterioration for Mycobacterium avium complex pulmonary disease

BackgroundEthambutol ocular toxicity is a major problem during combination chemotherapy for Mycobacterium avium complex (MAC) pulmonary disease (MAC-PD) due to years-long therapy for MAC.ObjectivesThis study aimed to identify the lower dose of daily ethambutol that can reduce ocular toxicity.MethodsWe retrospectively reviewed the medical records of 312 patients who visited The University of Tokyo Hospital between January 2007 and December 2017 for nontuberculous mycobacterial pulmonary disease. Seventy-six patients with MAC-PD who were treated with combination chemotherapy for the first time were analyzed in this study.ResultsEthambutol was discontinued because of visual symptoms in 13 patients (17%), 7 of whom were diagnosed with ethambutol ocular neuropathy. The dose per body weight was significantly higher in patients who developed ocular neuropathy than in those who did not (15.4 mg/kg/d vs. 12.5 mg/kg/d, respectively; p = 0.048). We assigned patients to higher or lower dose groups according to the median dose of 12.5 mg/kg/d. Although ocular neuropathy developed in 6 out of 38 patients in the higher dose group, ocular neuropathy developed in 1 out of 38 patients in the lower dose group (16% vs. 3%, respectively; p = 0.038). The failures of sputum culture conversion and radiological improvement were not significantly different between the two groups (p = 0.638 and 0.305, respectively). Macrolide resistance developed in one patient per group during follow-up (3% per group, p = 0.945).ConclusionsA lower dose of ethambutol may reduce ocular toxicity without radiological deterioration for pulmonary MAC infection.     

Two cases of chronic obstructive pulmonary disease evaluated by dynamic-ventilatory digital radiography for pulmonary function and assessment of treatment efficacy

Spirometry is a crucial test used in the diagnosis and monitoring of patients with chronic obstructive pulmonary disease (COPD). Severe acute respiratory syndrome coronavirus 2 pandemic has posed numerous challenges in performing spirometry. Dynamic-ventilatory digital radiography (DR) provides sequential chest radiography images during respiration with lower doses of radiation than conventional X-ray fluoroscopy and computed tomography. Recent studies revealed that parameters obtained from dynamic DR are promising for evaluating pulmonary function of COPD patients. We report two cases of COPD evaluated by dynamic-ventilatory DR for pulmonary function and treatment efficacy and discuss the potential of dynamic DR for evaluating COPD therapy.     

Lobar distribution of non-emphysematous gas trapping and lung hyperinflation in chronic obstructive pulmonary disease

BackgroundLung hyperinflation in chronic obstructive pulmonary disease (COPD) is closely associated with emphysema and non-emphysematous gas trapping, termed functional small airway disease (fSAD), on inspiratory and expiratory computed tomography (CT). Because the cranial-caudal emphysema distribution affects pulmonary function and fSAD may precede emphysema on CT, we tested the hypothesis that lobar fSAD distribution would affect lung hyperinflation differently in COPD with minimal and established emphysema.MethodsThe volume percentages of fSAD and emphysema (fSAD% and Emph%) over the upper and lower lobes were measured using inspiratory and expiratory CT in 70 subjects with COPD. Subjects were divided into those with minimal and established emphysema (n = 36 and 34) using a threshold of 10% Emph% in the whole lung.ResultsIn the minimal emphysema group, fSAD% in the upper and lower lobes was positively correlated with functional residual capacity (FRC) and residual volume to total lung capacity ratio (RV/TLC), and the correlation of fSAD% with RV/TLC was greater in the lower lobes. Conversely, in the established emphysema group, fSAD% in the upper and lower lobes was correlated with RV/TLC, but not with FRC. In multivariate analysis, fSAD% in the lower lobes, but not in the upper lobes, was associated with RV/TLC in subjects with minimal emphysema after adjusting for age, smoking status, and bronchodilator use.ConclusionNon-emphysematous gas trapping in the upper and lower lobes has a distinct physiological effect, especially in COPD with minimal emphysema. This local evaluation might allow sensitive detection of changes in lung hyperinflation in COPD.     

Comparison of the chest computed tomography findings between patients with pulmonary tuberculosis and those with Mycobacterium avium complex lung disease

BackgroundSince the computed tomography (CT) findings of nontuberculous mycobacterial lung disease are similar to those of pulmonary tuberculosis (PTB), we often have difficulty differentiating the two. In this study, we compared the differences in chest CT findings and their locations between cases of PTB and Mycobacterium avium complex lung disease (MACLD).MethodsThe subjects were 100 MACLD patients and 42 PTB patients treated at our hospital from May 2005 to August 2015. The CT findings were retrospectively evaluated.ResultsPTB more frequently showed lung shadows with calcification inside the lesion, calcification of the mediastinal/hilar lymph node, and pleural effusion on CT than MACLD, while extensive bronchiectasis and granular/large shadows connected to bronchiectasis were more frequently observed with MACLD than PTB. For cavitary lesions, the thinnest part of the cavity wall with MACLD was thinner than that with PTB. Granular shadows, large shadows, and bronchiectasis were typically distributed to the right upper lobe and left upper division in PTB cases vs. the right intermediate lobe and left lingula in MACLD.ConclusionsChest CT findings would therefore be useful for distinguishing PTB and MACLD when typical findings are observed.     

Serum amyloid A: A potential biomarker of lung disorders

Serum amyloid A is an acute-phase protein with multiple immunological functions. Serum amyloid A is involved in lipid metabolism, inflammatory reactions, granuloma formation, and cancerogenesis. Additionally, serum amyloid A is involved in the pathogenesis of different autoimmune lung diseases. The levels of serum amyloid A has been evaluated in biological fluids of patients with different lung diseases, including autoimmune disorders, chronic obstructive pulmonary diseases, obstructive sleep apnea syndrome, sarcoidosis, asthma, lung cancer, and other lung disorders, such as idiopathic pulmonary fibrosis, tuberculosis, radiation pneumonitis, and cystic fibrosis. This review focuses on the cellular and molecular interactions of serum amyloid A in different lung diseases and suggests this acute-phase protein as a prognostic marker.     

Predictors of acute exacerbation in biopsy-proven idiopathic pulmonary fibrosis

BackgroundAcute exacerbation (AE) is a major cause of death in patients with idiopathic pulmonary fibrosis (IPF). Current evidence on AE-IPF has been largely based on clinical, rather than pathological, analyses.MethodsWe investigated AE incidence and its predictors using clinical, radiological, and pathological data of patients diagnosed with IPF by multi-disciplinary discussion.This study, a secondary analysis of previous research, included 155 patients with IPF who underwent surgical lung biopsy (SLB). Cumulative AE incidence was evaluated by the Kaplan–Meier method. Predictors of AE-IPF were analyzed with a Fine-Gray sub-distribution hazard model. Sub-analysis was performed using propensity score-matching analysis.ResultsIn this cohort, the median age of the patients was 66 years and the median percent-predicted forced vital capacity was 82.8%. The cumulative AE incidence rates at 30 days and one year post SLB were 1.9% and 7.6%, respectively. On multivariable analysis, a lower percent-predicted diffusing capacity of the lung for carbon monoxide (%DL_CO) (hazard ratio 0.98 per 1% increase, P = 0.02) and fibroblastic foci (FF)-present (vs. absent; hazard ratio 3.01, P = 0.04) were independently associated with a higher incidence of AE. The propensity score-matching analysis with adjustment for age, gender, and %DL_CO revealed that the cumulative AE incidence rate was significantly higher in the FF-present subgroup than in the FF-absent subgroup (1-year incidence rate, 10.5% vs. 0%, respectively; P = 0.04 by Gray's test).ConclusionsFF and %DL_CO were independent predictors of AE in patients with biopsy-proven IPF. FF may be associated with the pathogenesis of AE-IPF.     

Various factors contribute to death in patients with different types of pulmonary hypertension: A retrospective pilot study from a single tertiary center

BackgroundA few studies have focused on the cause of death from different types of pulmonary hypertension (PH). This study aimed to systematically analyze the primary and secondary causes of death and compare the profiles between different PH groups.MethodsThe contribution of PH to death was assessed in precapillary PH (i.e., group 1 [pulmonary arterial hypertension], group 3 [PH associated with lung disease], and group 4 [chronic thromboembolic PH]) using specific criteria; death was classified into three categories: PH death (death due to PH only), PH-related death, and PH-unrelated death. Disorders other than PH that contributed to death were analyzed, and mortality profiles were compared between groups.ResultsEighty deceased patients with PH were examined (group 1, n = 28; group 3, n = 39; and group 4, n = 13). The contribution of PH to death was significantly different between the three groups. “PH death” was most common in group 1 (61%), “PH-related death” in group 3 (56%), and “PH-related death” and “PH-unrelated death” in group 4 (38% for both). The highest contributing factor to death other than PH was respiratory failure in group 3 and malignant disease in group 4.ConclusionsSignificant variations in the causes of death were observed in groups 1, 3, and 4 PH patients. In addition to PH, respiratory failure and malignant disease significantly contributed to death in group 3 and group 4 PH, respectively. Understanding the precise death cause may be important in achieving better outcomes in PH patients.     

Grape seed procyanidin suppresses inflammation in cigarette smoke-exposed pulmonary arterial hypertension rats by the PPAR-γ/COX-2 pathway

Background and aimPulmonary arterial hypertension (PAH) is characterized by pulmonary vascular remodeling, which is mainly caused by inflammation. Inhibiting inflammation can relieve PAH. Grape seed procyanidin (GSP) possesses remarkable anti-inflammatory property and vascular protective function. In this experiment, we verified the anti-inflammatory property of GSP in cigarette smoke-exposed PAH rats and revealed its molecular mechanism.Methods and resultsIn vivo, 45 Sprague Dawley (SD) rats were divided into 5 groups randomly, treated with normoxia/cigarette smoke (CS)/GSP + CS/CS + solvent/GSP. After GSP + CS administration, a decrease in mPAP, PVR, RVHI, WT%, and WA% was detected in the rats as compared to those treated with CS. In vitro, the proliferation of pulmonary arterial smooth muscle cells (PASMCs) caused by cigarette smoke extract (CSE) was effectively attenuated with GSP + CSE administration. Furthermore, GSP significantly increased the expression of peroxisome proliferator-activated receptor γ (PPAR-γ) together with the lowered expression level of cyclooxygenase 2 (COX-2) in PASMCs co-incubated with CSE.ConclusionThese findings indicate that GSP ameliorates inflammation by the PPAR-γ/COX-2 pathway and finally inhibits the proliferation of PASMCs, which leads to pulmonary vascular remodeling.     

A case of intrapulmonary lymphangioma surrounded by pulmonary hilar structures

A 53-year-old man was referred to our hospital for examination of a nodule in the right hilar region observed on a chest roentgenogram. Computed tomography and magnetic resonance imaging revealed a 34 × 32-mm multilocular cystic mass with partial calcification adjacent to the hilar structures in the right upper lung lobe. The mass was resected using video-assisted thoracoscopic surgery and identified as pulmonary cystic lymphangioma through postoperative histopathological analysis. Intrapulmonary lymphangioma is an uncommon benign tumor, with only few reports of surgically resected cases. We describe our surgical findings and recommend surgical resection where possible for suspected intrapulmonary lymphangioma.     

Bronchoscopy for the diagnosis of nontuberculous mycobacterial pulmonary disease: Specificity and diagnostic yield in a retrospective cohort study

BackgroundBronchoscopy is a recognized method for obtaining specimens for the diagnosis of nontuberculous mycobacterial pulmonary disease (NTM-PD). However, its diagnostic properties remain to be elucidated. The aim of this study was to determine the specificity of bronchoscopy for the diagnosis of NTM-PD, and to examine the diagnostic yield of bronchoscopy for detecting nontuberculous mycobacteria (NTM) when patients cannot expectorate sputum with NTM.MethodsThis retrospective cohort study included 2657 patients who underwent bronchoscopy and mycobacterial culture between January 2004 and June 2018 in a tertiary care center in Tokyo, Japan. To examine the specificity of bronchoscopy, the first cohort comprised patients who underwent bronchoscopy for the diagnosis of lung cancer and mycobacterial culture. To investigate the diagnostic yield, patients with nodular bronchiectasis who underwent bronchoscopy for the diagnosis of NTM-PD were enrolled into the second cohort.ResultsIn total, 919 patients were diagnosed with lung cancer, 19 patients showed positive culture for NTM, and 14 patients showed findings for NTM-PD. Accordingly, the specificity was calculated as 900/905 (99.4%). In addition, NTM-PD was suspected before bronchoscopy in 199 patients; the diagnostic yield was 105/199 (52.8%). Four factors were associated with NTM-PD: upper lobe examination, absence of specific bacteria, absence of connective tissue disease, and a higher total computed tomography score.ConclusionsBronchoscopy has a high specificity for the diagnosis of NTM-PD. In addition, even when NTM is undetected in sputum, bronchoscopy may detect mycobacteria in approximately half of the patients suspected of having NTM-PD.     

Chondroitin sulfate in tissue remodeling: Therapeutic implications for pulmonary fibrosis

Fibrosis is characterized by the deposition of extracellular matrix (ECM) proteins, while idiopathic pulmonary fibrosis (IPF) is a chronic respiratory disease characterized by dysregulated tissue repair and remodeling. Anti-inflammatory drugs, such as corticosteroids and immunosuppressants, and antifibrotic drugs, like pirfenidone and nintedanib, are used in IPF therapy. However, their limited effects suggest that single mediators are inadequate to control IPF. Therefore, therapies targeting the multifactorial cascades that regulate tissue remodeling in fibrosis could provide alternate solutions. ECM molecules have been shown to modulate various biological functions beyond tissue structure support and thus, could be developed into novel therapeutic targets for modulating tissue remodeling. Among ECM molecules, glycosaminoglycans (GAG) are linear polysaccharides consisting of repeated disaccharides, which regulate cell-matrix interactions. Chondroitin sulfate (CS), one of the major GAGs, binds to multifactorial mediators in the ECM and reportedly participates in tissue remodeling in various diseases; however, to date, its biological functions have drawn considerably less attention than other GAGs, like heparan sulfate. In the present review, we discuss the involvement and regulation of CS in tissue remodeling and pulmonary fibrotic diseases, its role in pulmonary fibrosis, and the therapeutic approaches targeting CS.