Evidence for Environmental-Human Microbiota Transfer at a Manufacturing Facility with Novel Work-related Respiratory Disease.

Rationale: Workers' exposure to metalworking fluid (MWF) has been associated with respiratory disease.Objectives: As part of a public health investigation of a manufacturing facility, we performed a cross-sectional study using paired environmental and human sampling to evaluate the cross-pollination of microbes between the environment and the host and possible effects on lung pathology present among workers.Methods: Workplace environmental microbiota were evaluated in air and MWF samples. Human microbiota were evaluated in lung tissue samples from workers with respiratory symptoms found to have lymphocytic bronchiolitis and alveolar ductitis with B-cell follicles and emphysema, in lung tissue samples from control subjects, and in skin, nasal, and oral samples from 302 workers from different areas of the facility. In vitro effects of MWF exposure on murine B cells were assessed.Measurements and Main Results: An increased similarity of microbial composition was found between MWF samples and lung tissue samples of case workers compared with control subjects. Among workers in different locations within the facility, those that worked in the machine shop area had skin, nasal, and oral microbiota more closely related to the microbiota present in the MWF samples. Lung samples from four index cases and skin and nasal samples from workers in the machine shop area were enriched with Pseudomonas, the dominant taxa in MWF. Exposure to used MWF stimulated murine B-cell proliferation in vitro, a hallmark cell subtype found in the pathology of index cases.Conclusions: Evaluation of a manufacturing facility with a cluster of workers with respiratory disease supports cross-pollination of microbes from MWF to humans and suggests the potential for exposure to these microbes to be a health hazard.

Severe lung disease characterized by lymphocytic bronchiolitis, alveolar ductitis, and emphysema (BADE) in industrial machine-manufacturing workers.

BACKGROUND: A cluster of severe lung disease occurred at a manufacturing facility making industrial machines. We aimed to describe disease features and workplace exposures. METHODS: Clinical, functional, radiologic, and histopathologic features were characterized. Airborne concentrations of thoracic aerosol, metalworking fluid, endotoxin, metals, and volatile organic compounds were measured. Facility airflow was assessed using tracer gas. Process fluids were examined using culture, polymerase chain reaction, and 16S ribosomal RNA sequencing. RESULTS: Five previously healthy male never-smokers, ages 27 to 50, developed chest symptoms from 1995 to 2012 while working in the facility's production areas. Patients had an insidious onset of cough, wheeze, and exertional dyspnea; airflow obstruction (mean FEV1 = 44% predicted) and reduced diffusing capacity (mean = 53% predicted); and radiologic centrilobular emphysema. Lung tissue demonstrated a unique pattern of bronchiolitis and alveolar ductitis with B-cell follicles lacking germinal centers, and significant emphysema for never-smokers. All had chronic dyspnea, three had a progressive functional decline, and one underwent lung transplantation. Patients reported no unusual nonoccupational exposures. No cases were identified among nonproduction workers or in the community. Endotoxin concentrations were elevated in two air samples; otherwise, exposures were below occupational limits. Air flowed from areas where machining occurred to other production areas. Metalworking fluid primarily grew Pseudomonas pseudoalcaligenes and lacked mycobacterial DNA, but 16S analysis revealed more complex bacterial communities. CONCLUSION: This cluster indicates a previously unrecognized occupational lung disease of yet uncertain etiology that should be considered in manufacturing workers (particularly never-smokers) with airflow obstruction and centrilobular emphysema. Investigation of additional cases in other settings could clarify the cause and guide prevention.

The National Institute for Occupational Safety and Health B Reader Certification Program-An Update Report (1987 to 2018) and Future Directions.

OBJECTIVE: The National Institute for Occupational Safety and Health (NIOSH) B Reader Program provides the opportunity for physicians to demonstrate proficiency in the International Labour Office (ILO) system for classifying radiographs of pneumoconioses. We summarize trends in participation and examinee attributes and performance during 1987 to 2018. METHODS: Since 1987, NIOSH has maintained details of examinees and examinations. Attributes of examinees and their examination performance were summarized. Simple linear regression was used in trend analysis of passing rates over time. RESULTS: The mean passing rate for certification and recertification for the study period was 40.4% and 82.6%, respectively. Since the mid-1990s, the number of B Readers has declined and the mean age and years certified have increased. CONCLUSIONS: To address the declining B Reader population, NIOSH is currently taking steps to modernize the program and offer more opportunities for training and testing.

Computed Tomography Assessment for Transcatheter Aortic Valve Replacement.

Transcatheter aortic valve replacement has become a mainstream therapeutic option for patients with severe aortic stenosis who are at intermediate risk or high risk for surgical valve replacement. Computed tomography (CT) is now the standard imaging modality for preoperative vascular access planning an aortic annular sizing. This article reviews the established and potential future roles of CT in transcatheter aortic valve replacement.

Thymic hyperplasia after adjuvant chemotherapy in breast cancer.

We report 2 patients with breast cancer who were treated with surgery and adjuvant chemotherapy for stage IIa and stage I breast cancers. Follow-up CT scans showed an anterior mediastinal mass, raising concern for tumor recurrence. Thymectomy performed on the first patient, and close follow-up with radiographic studies on the second patient, revealed benign thymic enlargement. Thymic hyperplasia can occur after cytotoxic chemotherapy and may be due to rebound enlargement after initial atrophy caused by chemotherapy. Thymic hyperplasia after chemotherapy has been reported mostly in young age groups and is described in the literature to be associated with various types of cancers, including lymphomas, leukemias, testicular cancer, and sarcomas, and in the stem cell transplant setting. This is the first case series describing 2 patients with early stage breast cancer who, following adjuvant standard dose chemotherapy, developed thymic hyperplasia. Awareness of this unusual side effect in patients treated with chemotherapy may prevent unnecessary investigation and surgical intervention.

Pericardioesophageal fistula following left atrial ablation procedure.

We present a case of pericardioesophageal fistula formation in a 40 year old male who 23 days after undergoing a repeat ablation procedure for atrial fibrillation developed chest pressure, chills and diaphoresis. After initial labs and tests that demonstrated no evidence for acute myocardial ischemia, the patient underwent CT angiography of the chest. The study revealed pneumopericardium and a pericardial effusion. Suspicion was raised of perforation of the posterior left atrial myocardial wall with injury to adjacent esophagus. Water soluble contrast with transition to barium sulfate esophagram subsequently performed identified a perforation further affirming the postulate of a fistulous communication between the esophagus and pericardium. Transthoracic echocardiogram confirmed pericardial effusion but did not demonstrate myocardial defect. Endoscopic management was preferred and an esophageal stent was placed. Follow up esophagram showed an intact esophageal stent without evidence of extravasation.

"Extracaval shepherd's crook" sign: a characteristic radiographic sign of central venous catheter placement in the right internal thoracic vein.

Inaccurate positioning is a well-known and documented complication of central venous catheterization. Inadvertent placement of a central venous catheter into the right internal thoracic vein has been reported in the literature; however, the characteristic radiographic appearance for this complication has yet to be described. We report 3 cases that demonstrate central venous catheters improperly terminating in the right internal jugular vein. Characteristic radiographic findings of this altered catheter course are described. Recognition of these characteristic findings should prompt consideration for line repositioning or replacement.

Indium lung disease.

BACKGROUND: Reports of pulmonary fibrosis, emphysema, and, more recently, pulmonary alveolar proteinosis (PAP) in indium workers suggested that workplace exposure to indium compounds caused several different lung diseases. METHODS: To better understand the pathogenesis and natural history of indium lung disease, a detailed, systematic, multidisciplinary analysis of clinical, histopathologic, radiologic, and epidemiologic data for all reported cases and workplaces was undertaken. RESULTS: Ten men (median age, 35 years) who produced, used, or reclaimed indium compounds were diagnosed with interstitial lung disease 4-13 years after first exposure (n = 7) or PAP 1-2 years after first exposure (n = 3). Common pulmonary histopathologic features in these patients included intraalveolar exudate typical of alveolar proteinosis (n = 9), cholesterol clefts and granulomas (n = 10), and fibrosis (n = 9). Two patients with interstitial lung disease had pneumothoraces. Lung disease progressed following cessation of exposure in most patients and was fatal in two. Radiographic data revealed that two patients with PAP subsequently developed fibrosis and one also developed emphysematous changes. Epidemiologic investigations demonstrated the potential for exposure to respirable particles and an excess of lung abnormalities among coworkers. CONCLUSIONS: Occupational exposure to indium compounds was associated with PAP, cholesterol ester crystals and granulomas, pulmonary fibrosis, emphysema, and pneumothoraces. The available evidence suggests exposure to indium compounds causes a novel lung disease that may begin with PAP and progress to include fibrosis and emphysema, and, in some cases, premature death. Prospective studies are needed to better define the natural history and prognosis of this emerging lung disease and identify effective prevention strategies.

MR imaging of the chest using a contrast-enhanced breath-hold modified three-dimensional gradient-echo technique: comparison with two-dimensional gradient-echo technique and multidetector CT.

OBJECTIVE: The purpose of this study was to assess the feasibility of performing MR imaging of the chest using a fat-suppressed gadolinium-enhanced modified three-dimensional (3D) gradient-echo technique with a volumetric interpolated breath-hold (VIB) sequence compared with using a standard two-dimensional (2D) breath-hold gradient-echo technique. MR images obtained using both techniques were compared with multidetector CT (MDCT) scans. SUBJECTS AND METHODS: Paired gadolinium-enhanced 2D gradient-echo and 3D gradient-echo VIB images were acquired in 15 consecutive patients with suspected intrathoracic abnormalities. MDCT scans were available for comparison in 12 patients. Two reviewers independently analyzed the MR images obtained using the two techniques for overall quality, the degree of artifacts, and visibility of mediastinal or parenchymal abnormalities. The detectability of lesions on the 3D gradient-echo VIB images and 2D gradient-echo images was compared with the detectability of lesions on CT scans obtained in nine patients. RESULTS: In all cases, the MR images obtained using the 3D gradient-echo technique with the VIB sequence were rated superior to those obtained using the 2D gradient-echo technique for quality, depiction of mediastinal structures, and clarity of pulmonary vessels and central airways. On the 3D gradient-echo VIB images, the degree of phase artifacts was lower (p < 0.001), but the degree of pixel graininess was higher (p < 0.05). Detectability, confidence and conspicuity levels, and marginal delineation of the pulmonary lesions were rated higher statistically on the 3D gradient-echo VIB images than on the 2D gradient-echo images. Of the 31 solid pulmonary abnormalities depicted on MDCT, 27 (87.1%) were detected on the 3D gradient-echo VIB images, and 21 (67.7%) were seen on the 2D gradient-echo images (p < 0.05). The 3D gradient-echo VIB images showed all 14 mediastinal lesions (100%) seen on MDCT, whereas the 2D gradient-echo images showed 12 (85.7%) of the 14 lesions (p > or = 0.05). CONCLUSION: The gadolinium-enhanced modified 3D gradient-echo technique with the VIB sequence provides MR images that are superior in quality, have significantly fewer artifacts, and have a higher sensitivity for the detection of intrathoracic lesions compared with images obtained using the standard 2D gradient-echo technique.