Acute eosinophilic pneumonia following electronic cigarette use

The efficacy and acceptability of pharmacological monotherapies and e-cigarette on smoking cessation: a systemic review and network meta-analysis

Background and aims

Several pharmacological interventions, such as nicotine replacement therapy (NRT), varenicline, and bupropion, have been approved for clinical use of smoking cessation. E-cigarettes (EC) are increasingly explored by many RCTs for their potentiality in smoking cessation. In addition, some RCTs are attempting to explore new drugs for smoking cessation, such as cytisine. This network meta-analysis (NMA) aims to investigate how these drugs and e-cigarettes compare regarding their efficacy and acceptability.

Materials and methods

This systematic review and NMA searched all clinical studies on smoking cessation using pharmacological monotherapies or e-cigarettes published from January 2011 to May 2022 using MEDLINE, COCHRANE Library, and PsychINFO databases. NRTs were divided into transdermal (TDN) and oronasal nicotine (ONN) by administrative routes, thus 7 network nodes were set up for direct and indirect comparison. Two different indicators measured the efficacy: prevalent and continuous smoking abstinence. The drop-out rates measured the acceptability.

Results

The final 40 clinical studies included in this study comprised 77 study cohorts and 25,889 participants. Varenicline is more effective intervention to assist in smoking cessation during 16-32 weeks follow-up, and is very likely to prompt dropout. Cytisine shows more effectiveness in continuous smoking cessation but may also lead to dropout. E-cigarettes and oronasal nicotine are more effective than no treatment in encouraging prevalent abstinence, but least likely to prompt dropout. Finally, transdermal nicotine delivery is more effective than no treatment in continuous abstinence, with neither significant effect on prevalent abstinence nor dropout rate.

Conclusion

This review suggested and agreed that Varenicline, Cytisine and transdermal nicotine delivery, as smoking cessation intervention, have advantages and disadvantages. However, we had to have reservations about e-cigarettes as a way to quit smoking in adolescents.

E-cigarette-/Vape-Associated Lung Injury as a Cause of Interstitial Lung Disease

E-cigarette-/vape-associated lung injury (EVALI) refers to damage to lung tissue occurring as a result of e-cigarette utilization or via vaping of inhaled nicotine products. Vaping refers to the practice of inhaling an aerosol derived from heating a liquid or gas containing substances such as nicotine, cannabinoids, flavoring, or additives. Battery-operated e-cigarettes or vape pens are the vessels commonly used in this practice. EVALI, first described in the literature in 2019, has a non-specific course, presenting initially with cough and dyspnea. It can progress, however, to interstitial lung disease or result in damage to the lung parenchyma with concomitant inflammation and fibrosis. Imaging findings reflect the development of this inflammation and fibrosis, often visualized as ground-glass opacities on computed tomography (CT) scans. Formal biopsies are not required to make the diagnosis of EVALI, and thus, a gap exists in the scientific literature with regard to the pathology of lungs exposed to non-tetrahydrocannabinol (THC) e-cigarettes. The following case details the clinical course of a 62-year-old male who presented to the outpatient pulmonology office with symptomology and exposure history consistent with EVALI, unique in presentation due to the timeline of his disease development. The patient initially presented to the clinic for the evaluation of a non-productive cough and exertional dyspnea beginning one year ago, with an associated new home oxygen requirement of 2 liters via nasal cannula. The patient's past medical history was relevant for diffuse large B-cell lymphoma treated with the chemotherapeutic regimen that consists of etoposide phosphate, prednisone, vincristine sulfate (Oncovin), cyclophosphamide, doxorubicin hydrochloride (hydroxydaunorubicin), and rituximab, commonly known as EPOCH-R, as well as a social history relevant for a 35-pack-year smoking history. On further questioning, the patient revealed that following cessation of cigarette smoking, he began using non-THC e-cigarettes daily and had been doing so for 10 years prior to symptom onset. Imaging and biopsy findings consisted of a CT of the chest demonstrating concern for interstitial lung disease and an open lung biopsy demonstrating diffuse alveolar damage with eosinophilia. Given the patient's history, clinical symptoms, and imaging findings, a diagnosis of EVALI was established. This case was documented not only to increase awareness of the rising incidence of EVALI as the use of e-cigarettes and vapes becomes increasingly popular but also to further understand the inhalational injury sustained from non-THC e-cigarettes and other inhalational practices.

Cardiopulmonary Impact of Electronic Cigarettes and Vaping Products: A Scientific Statement From the American Heart Association

Vaping and electronic cigarette (e-cigarette) use have grown exponentially in the past decade, particularly among youth and young adults. Cigarette smoking is a risk factor for both cardiovascular and pulmonary disease. Because of their more limited ingredients and the absence of combustion, e-cigarettes and vaping products are often touted as safer alternative and potential tobacco-cessation products. The outbreak of e-cigarette or vaping product use-associated lung injury in the United States in 2019, which led to >2800 hospitalizations, highlighted the risks of e-cigarettes and vaping products. Currently, all e-cigarettes are regulated as tobacco products and thus do not undergo the premarket animal and human safety studies required of a drug product or medical device. Because youth prevalence of e-cigarette and vaping product use was as high as 27.5% in high school students in 2019 in the United States, it is critical to assess the short-term and long-term health effects of these products, as well as the development of interventional and public health efforts to reduce youth use. The objectives of this scientific statement are (1) to describe and discuss e-cigarettes and vaping products use patterns among youth and adults; (2) to identify harmful and potentially harmful constituents in vaping aerosols; (3) to critically assess the molecular, animal, and clinical evidence on the acute and chronic cardiovascular and pulmonary risks of e-cigarette and vaping products use; (4) to describe the current evidence of e-cigarettes and vaping products as potential tobacco-cessation products; and (5) to summarize current public health and regulatory efforts of e-cigarettes and vaping products. It is timely, therefore, to review the short-term and especially the long-term implications of e-cigarettes and vaping products on cardiopulmonary health. Early molecular and clinical evidence suggests various acute physiological effects from electronic nicotine delivery systems, particularly those containing nicotine. Additional clinical and animal-exposure model research is critically needed as the use of these products continues to grow.

Clinical manifestations of EVALI in adolescents before and during the COVID-19 pandemic

INTRODUCTION

E-cigarette, or vaping, product use-associated lung injury (EVALI) results from inhaling the aerosol of e-cigarettes and has similar clinical features to coronavirus disease 2019 (COVID-19). EVALI case counts since the declaration of the COVID-19 pandemic is unknown.

METHODS

A retrospective electronic health record chart review of adolescents hospitalized at one institution with EVALI was conducted. Clinical characteristics and hospital course of patients hospitalized during the pandemic were compared to those prepandemic.

RESULTS

The clinical presentation of adolescents hospitalized prior-to (n = 19) and during the COVID-19 pandemic (n = 22) were similar with respect to constitutional, respiratory, and gastrointestinal symptoms. All patients hospitalized during the pandemic were tested for COVID-19 at least once. Only one patient had a positive SARS-CoV-2 RT-PCR test result. Thirty-one out of 39 patients treated with corticosteroids had clinical improvement within 24 h (79%). Patients hospitalized during the pandemic had a shorter median length of stay (5 vs. 7 days, p < 0.01), and were less often discharged with home oxygen (1 vs. 6 patients, p = 0.04). Pulmonary function tests improved pre- to postcorticosteroid treatment and postcorticosteroid to follow-up.

CONCLUSIONS

Eliciting a history of vaping in adolescents presenting with constitutional, respiratory, and gastrointestinal symptoms is important to identify EVALI cases, which have continued throughout the COVID-19 pandemic. A shorter length of stay with less need for mechanical ventilation and home oxygen in adolescents hospitalized during the pandemic may reflect increased familiarity with EVALI characteristics. Corticosteroids led to clinical and pulmonary function improvement.

The E-cigarette or Vaping Product Use-Associated Lung Injury Epidemic: Pathogenesis, Management, and Future Directions: An Official American Thoracic Society Workshop Report

E-cigarette or vaping product use-associated lung injury (EVALI) is a severe pulmonary illness associated with the use of e-cigarettes or vaping products that was officially identified and named in 2019. This American Thoracic Society workshop was convened in 2021 to identify and prioritize research and regulatory needs to adequately respond to the EVALI outbreak and to prevent similar instances of disease associated with e-cigarette or vaping product use. An interdisciplinary group of 26 experts in adult and pediatric clinical care, public health, regulatory oversight, and toxicology were convened for the workshop. Four major topics were examined: 1) the public health and regulatory response to EVALI; 2) EVALI clinical care; 3) mechanisms contributing to EVALI; and 4) needed actions to address the health effects of EVALI. Oral presentations and group discussion were the primary modes used to identify top priorities for addressing EVALI. Initiatives including a national EVALI case registry and biorepository, integrated electronic medical record coding system, U.S. Food and Drug Administration regulation and enforcement of nicotine e-cigarette standards, regulatory authority over nontobacco-derived e-cigarettes, training in evaluating exogenous exposures, prospective clinical studies, standardized clinical follow-up assessments, ability to more readily study effects of cannabinoid e-cigarettes, and research to identify biomarkers of exposure and disease were identified as critical needs. These initiatives will require substantial federal investment as well as changes to regulatory policy. Overall, the workshop identified the need to address the root causes of EVALI to prevent future outbreaks. An integrated approach from multiple perspectives is required, including public health; clinical, basic, and translational research; regulators; and users of e-cigarettes. Improving the public health response to reduce the risk of another substantial disease-inducing event depends on coordinated actions to better understand the inhalational toxicity of these products, informing the public of the risks, and developing and enforcing regulatory standards for all e-cigarettes.

Impact of vaping on respiratory health

Widespread uptake of vaping has signaled a sea change in the future of nicotine consumption. Vaping has grown in popularity over the past decade, in part propelled by innovations in vape pen design and nicotine flavoring. Teens and young adults have seen the biggest uptake in use of vape pens, which have superseded conventional cigarettes as the preferred modality of nicotine consumption. Relatively little is known, however, about the potential effects of chronic vaping on the respiratory system. Further, the role of vaping as a tool of smoking cessation and tobacco harm reduction remains controversial. The 2019 E-cigarette or Vaping Use-Associated Lung Injury (EVALI) outbreak highlighted the potential harms of vaping, and the consequences of long term use remain unknown. Here, we review the growing body of literature investigating the impacts of vaping on respiratory health. We review the clinical manifestations of vaping related lung injury, including the EVALI outbreak, as well as the effects of chronic vaping on respiratory health and covid-19 outcomes. We conclude that vaping is not without risk, and that further investigation is required to establish clear public policy guidance and regulation.

Acute eosinophilic pneumonia caused by nicotine‐free vaping in an adolescent patient: A case report

An 18‐year‐old man was admitted to our hospital with pneumonia 4 days after he initiated vaping. The patient did not show improvement after ceftriaxone and azithromycin treatment. The cell count of the bronchoalveolar lavage fluid (BALF) revealed 64% eosinophils and 18% lymphocytes. Based on the BALF findings, the patient met the current diagnostic criteria and was diagnosed with vaping‐induced acute eosinophilic pneumonia (AEP). AEP caused by nicotine‐free vaping is rare in Japan. Thus, in cases of AEP, the patient's history of cigarette smoking as well as vaping should be considered.

Association between electronic cigarette use in children and adolescents and coughing a systematic review

BACKGROUND

The use of electronic cigarettes (e-cigarettes) among adolescents is increasing worldwide. E-cigarettes are marketed as a safe alternative to other tobacco products. The aim of this systematic review is to evaluate whether e-cigarette use in children and adolescents is associated with coughing.

METHOD

Studies were identified through systematic searches of Excerpta Medica Database, Medline, Cumulative Index to Nursing and Allied Health Literature, British Nursing Index, OVID Emcare, Health Management Information Consortium, PsycINFO, and Allied and Complementary Medicine. The Grey Literature was also searched. Selected studies either contained only children and adolescents as study participants or if adults were included, the data for adolescents and children must be presented separately.

RESULTS

Seven studies were selected from 104. Three studies compared e-cigarette users with nonusers; two studies found a significant association between coughing and e-cigarette use in adolescence. Two studies investigated whether adolescents attributed their symptoms to their e-cigarette use. One study reported that coughing was the most likely negative symptom reported by adolescents on initiation of e-cigarette use; the other study found that adolescents, on initiation of e-cigarette use, reported coughing. Two studies looked at the cases of children and adolescents who had presented to the hospital after e-cigarette use and found coughing was a common presenting symptom.

CONCLUSION

This systematic review shows that adolescent use of e-cigarettes is associated with increased coughing and e-cigarette users are more likely to report coughing compared to non-users.

Harms of Electronic Cigarettes: What the Healthcare Provider Needs to Know

Electronic cigarettes (e-cigarettes) reached the market without either extensive preclinical toxicology testing or long-term safety trials that would be required of conventional therapeutics or medical devices. E-cigarettes are considered a tobacco product and as such have no manufacturing quality or safety standards. A growing body of evidence documents severe harms from e-cigarette use, including injuries from product explosions, nicotine poisoning, and severe lung diseases. Commonly used e-cigarette components have significant inhalation toxicity. Emerging evidence from laboratory studies suggests substantial reason for concern for long-term harms, including risk for cardiovascular disease, chronic obstructive lung disease, and cancer. Rather than helping people stop smoking, e-cigarette use is associated with reduced rates of smoking cessation among current smokers and an increased risk of relapse to smoking among former smokers. The World Health Organization advises, "Unlike the tried and tested nicotine and non-nicotine pharmacotherapies that are known to help people quit tobacco use, WHO does not endorse e-cigarettes as cessation aids." Careful evaluation of all the available research justifies a strong recommendation that healthcare providers should neither prescribe nor recommend e-cigarettes for persons who are tobacco dependent. If a patient is dependent on e-cigarettes, the healthcare provider should provide counseling and treatment (of nicotine dependence) to help the patient to stop their e-cigarette use.

Electronic cigarette use (vaping) and patterns of tobacco cigarette smoking in pregnancy-evidence from a population-based maternity survey in England

OBJECTIVES

Exposure to tobacco products during pregnancy presents a potential harm to both mother and baby. This study sought to estimate the prevalence of vaping during pregnancy and to explore the factors and outcomes associated with vaping in pregnancy.

SETTING

England.

PARTICIPANTS

Women who gave birth between 15th and 28th October 2017.

METHODS

A cross-sectional population-based postal survey of maternal and infant health, the National Maternity Survey (NMS) 2018. The prevalence of vaping and patterns of cigarette smoking were estimated, and regression analysis was used to explore associations between maternal characteristics and vaping, and between vaping and birth outcomes.

OUTCOME MEASURES

Unweighted and weighted prevalence of vaping with 95% confidence intervals, and unadjusted and adjusted relative risks or difference in means for the association of participant characteristics and secondary outcomes with vaping. Secondary outcome measures were: preterm birth, gestational age at birth, birthweight, and initiation and duration of breastfeeding.

RESULTS

A total of 4,509 women responded to the survey. The prevalence of vaping in pregnancy was 2.8% (95%CI 2.4% to 3.4%). This varied according to the pattern of cigarette smoking in pregnancy: 0.3% in never-smokers; 3.3% in ex-smokers; 7.7% in pregnancy-inspired quitters; 9.5% in temporary quitters; and 17.7% in persistent smokers. Younger women, unmarried women, women with fewer years of formal education, women living with a smoker, and persistent smokers were more likely to vape, although after adjusting for pattern of cigarette smoking and maternal characteristics, persistent smoking was the only risk factor. We did not find any association between vaping and preterm birth, birthweight, or breastfeeding.

CONCLUSIONS

The prevalence of vaping during pregnancy in the NMS 2018 was low overall but much higher in smokers. Smoking was the factor most strongly associated with vaping. Co-occurrence of vaping with persistent smoking has the potential to increase the harms of tobacco exposure in pregnant women and their infants.

Chronic E-Cigarette Aerosol Inhalation Alters the Immune State of the Lungs and Increases ACE2 Expression, Raising Concern for Altered Response and Susceptibility to SARS-CoV-2

Conventional smoking is known to both increase susceptibility to infection and drive inflammation within the lungs. Recently, smokers have been found to be at higher risk of developing severe forms of coronavirus disease 2019 (COVID-19). E-cigarette aerosol inhalation (vaping) has been associated with several inflammatory lung disorders, including the recent e-cigarette or vaping product use-associated lung injury (EVALI) epidemic, and recent studies have suggested that vaping alters host susceptibility to pathogens such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To assess the impact of vaping on lung inflammatory pathways, including the angiotensin-converting enzyme 2 (ACE2) receptor known to be involved in SARS-CoV-2 infection, mice were exposed to e-cigarette aerosols for 60 min daily for 1-6 months and underwent gene expression analysis. Hierarchical clustering revealed extensive gene expression changes occurred in the lungs of both inbred C57BL/6 mice and outbred CD1 mice, with 2,933 gene expression changes in C57BL/6 mice, and 2,818 gene expression changes in CD1 mice (>abs 1.25-fold change). Particularly, large reductions in IgA and CD4 were identified, indicating impairment of host responses to pathogens via reductions in immunoglobulins and CD4 T cells. CD177, facmr, tlr9, fcgr1, and ccr2 were also reduced, consistent with diminished host defenses via decreased neutrophils and/or monocytes in the lungs. Gene set enrichment (GSE) plots demonstrated upregulation of gene expression related to cell activation specifically in neutrophils. As neutrophils are a potential driver of acute lung injury in COVID-19, increased neutrophil activation in the lungs suggests that vapers are at higher risk of developing more severe forms of COVID-19. The receptor through which SARS-CoV-2 infects host cells, ACE2, was found to have moderate upregulation in mice exposed to unflavored vape pens, and further upregulation (six-fold) with JUUL mint aerosol exposure. No changes were found in mice exposed to unflavored Mod device-generated aerosols. These findings suggest that specific vaping devices and components of e-liquids have an effect on ACE2 expression, thus potentially increasing susceptibility to SARS-CoV-2. In addition, exposure to e-cigarette aerosols both with and without nicotine led to alterations in eicosanoid lipid profiles within the BAL. These data demonstrate that chronic, daily inhalation of e-cigarette aerosols fundamentally alters the inflammatory and immune state of the lungs. Thus, e-cigarette vapers may be at higher risk of developing infections and inflammatory disorders of the lungs.

A 20-Year-Old Man with e-Cigarette or Vaping Product Use-Associated Lung Injury (EVALI) and Thrombotic Coagulopathy

BACKGROUND In 2019, the US Centers for Disease Control and Prevention (CDC) described the criteria for the diagnosis of e-cigarette or vaping product use-associated lung injury (EVALI), which may be caused by contamination of delta-9-tetrahydrocannabinoid (THC) e-liquids with vitamin E acetate. This report describes a case of a 20-year-old man with a history of recreational drug use that included vaping, who presented with EVALI and a coagulopathy associated with thrombotic events. CASE REPORT We present a 20-year-old patient who worked at a cannabidiol (CBD) manufacturing facility with a history of e-cigarette use and polysubstance abuse in remission who presented with respiratory and gastrointestinal symptoms accompanied by 50-pound weight loss over 6 months. The patient had been vaping with nicotine and THC-containing e-cigarettes multiple times per day for 1.5 years. He met the CDC surveillance criteria for EVALI, consisting of respiratory symptoms and infiltrates on imaging within 90 days of vaping, and was found to have eosinophilic pneumonia secondary to THC-containing e-cigarette use. Additionally, thrombi were detected in the pulmonary arteries, right saphenous vein, and right ventricle. A segmental infarct was noted in the inferior pole of the left kidney. CONCLUSIONS We present the second case report potentially linking e-cigarette use with clinically significant thrombogenesis, the first with both arterial and venous thromboses. This report demonstrates the importance of taking a history of e-cigarette use in patients presenting with lung injury. Although EVALI and the diagnostic criteria have only recently been described, systemic effects, including coagulopathy, are now being reported.

E-cigarettes and Vaping, Product-use Associated Lung Injury: A Case Series of Adolescents

Introduction

Lung injury associated with the use of electronic cigarettes and vaping (EVALI) was first identified in 2019. Since then, clusters of cases have been reported in the literature. Our aim was to describe the clinical presentation of adolescents with EVALI in the emergency department and their clinical outcomes.

Case Series

In our case series, we identified seven adolescents diagnosed with EVALI. We describe their signs and symptoms on presentation to the emergency department and their clinical course. The most common symptoms on presentation were cough, shortness of breath, and vomiting. Each of these symptoms was seen in 71% of patients (n = 5), although not always together. Sinus tachycardia was noticed in 100% of patients (n = 7) and tachypnea in 85% (n = 6). While 85% (n = 6) required hospitalization for respiratory support, all patients were later discharged home on room air. After the diagnosis of EVALI, 85% of patients (n = 6) were treated with steroids.

Conclusion

EVALI is a new disease with unclear mechanisms that commonly presents with symptoms of cough, shortness of breath, and vomiting. It causes severe respiratory compromise in the adolescent population, requiring hospitalization and respiratory support.

E-cigarette use and respiratory disorders: an integrative review of converging evidence from epidemiological and laboratory studies

Background

Use of electronic cigarettes (e-cigarettes) is prevalent among adolescents and young adults, but there has been limited knowledge about health consequences in human populations. We conduct a systematic review and meta-analysis of results on respiratory disorders from studies of general-population samples and consider the mapping of these results to findings about biological processes linked to e-cigarettes in controlled laboratory studies.

Method

We conducted a literature search and meta-analysis of epidemiological studies on the association of e-cigarette use with asthma and with COPD. We discuss findings from laboratory studies about effects of e-cigarettes on four biological processes: cytotoxicity, oxidative stress/inflammation, susceptibility to infection and genetic expression.

Results

Epidemiological studies, both cross-sectional and longitudinal, show a significant association of e-cigarette use with asthma and COPD, controlling for cigarette smoking and other covariates. For asthma (n=15 studies), the pooled adjusted odds ratio (aOR) was 1.39 (95% CI 1.28–1.51); for COPD (n=9 studies) the aOR was 1.49 (95% CI 1.36–1.65). Laboratory studies consistently show an effect of e-cigarettes on biological processes related to respiratory harm and susceptibility to illness, with e-cigarette conditions differing significantly from clean-air controls, although sometimes less than for cigarettes.

Conclusions

The evidence from epidemiological studies meets established criteria for consistency, strength of effect, temporality, and in some cases a dose–response gradient. Biological plausibility is indicated by evidence from multiple laboratory studies. We conclude that e-cigarette use has consequences for asthma and COPD, which is of concern for respirology and public health.

Epidemiological studies show a relationship of e-cigarette use with asthma and COPD, and laboratory studies show their adverse effects on four biological processes. It can be concluded that e-cigarette use is of significant concern for public health.https://bit.ly/3drH4pj

E-cigarettes: A novel therapy or a looming catastrophe

Electronic cigarettes (e-cigarettes) were originally developed in 2003 as healthier alternatives to conventional tobacco cigarettes. Their popularity has since significantly increased and both users and nonusers are exposed to their aerosol and product constituents. Although some evidence suggests that e-cigarette use may facilitate smoking cessation, definitive data are lacking and e-cigarettes are not approved by the Food and Drug Administration as a cessation aid. While e-cigarette aerosol contains fewer toxins than conventional cigarette smoke, studies evaluating whether e-cigarettes are less harmful are inconclusive. The health impact of e-cigarettes for both users and nonusers cannot be determined with currently available data, and there are both environmental concerns and issues regarding nonuser exposure. Most of the currently available data related to the health effects of e-cigarettes do not evaluate their effects on the general population and evidence regarding the systemic health effects of e-cigarettes is limited. In addition, there has been a recent rise in vaping-related lung injuries. Therefore, the detrimental effects of e-cigarette use should be further investigated, and every effort should be made to increase public awareness of the harmful effects of e-cigarettes.

Lung disorders induced by respirable organic chemicals

Respirable organic chemicals were originally thought to cause allergic respiratory diseases, such as bronchial asthma and hypersensitivity pneumonitis, and believed not to cause lung disorders derived from inflammatory or fibrotic processes such as pulmonary fibrosis and interstitial pneumonitis. It has recently been reported, however, that exposure to organic chemicals can cause interstitial lung diseases. In this review, we discuss the clinical features of occupational asthma and hypersensitivity pneumonitis, as well as other lung disorders, including interstitial pneumonitis, caused by humidifier disinfectants in Korea and by a cross-linked acrylic acid-based polymer (CL-PAA) in Japan.

Overview of Pathologic Findings of Vaping in the Context of an Autopsy Patient With Chronic Injury

CONTEXT.—

Electronic cigarettes are handheld devices that heat an inner liquid containing chemicals to be aerosolized and inhaled, and have become a popular alternative to conventional cigarettes. Their use, termed vaping, has been linked to severe injury, with 2711 cases of associated lung injury and 60 deaths reported to the Centers for Disease Control and Prevention at the time of writing. Published case reports and series have emerged detailing clinical and imaging characteristics of vaping-induced lung injury. However, the pathologic characteristics of these induced injuries are still being established, particularly findings occurring over time.

OBJECTIVE.—

To illustrate the autopsy findings of an older patient who died of vaping-induced injury after prolonged symptomology and to provide a review of the most recent literature regarding the basic science, epidemiology, clinical presentation, imaging characteristics, and pathology of vaping-induced lung injury.

DATA SOURCES.—

Autopsy case and peer-reviewed literature.

CONCLUSIONS.—

Vaping-induced lung injury has emerged as a public health issue, and this case represents a rare opportunity to evaluate this issue at autopsy. Most commonly, the injury has been attributed to tetrahydrocannabinol product use as opposed to nicotine. This case demonstrates that as today's young and relatively healthy "vapers" grow older and develop the comorbidities that come with advanced age, there is serious risk of chronic lung damage from vaping that could result in death. Further observations and studies, particularly autopsy evidence, are clearly important to understand the possible outcomes.

Differential plasma exosomal long non-coding RNAs expression profiles and their emerging role in E-cigarette users, cigarette, waterpipe, and dual smokers

Long non-coding RNAs (lncRNAs) are the varied set of transcripts that play a critical role in biological processes like gene regulation, transcription, post-transcriptional modification, and chromatin remodeling. Recent studies have reported the presence of lncRNAs in the exosomes that are involved in regulating cell-to-cell communication in lung pathologies including lung cancer, chronic obstructive pulmonary disease (COPD), asthma, and idiopathic pulmonary fibrosis (IPF). In this study, we compared the lncRNA profiles in the plasma-derived exosomes amongst non-smokers (NS), cigarette smokers (CS), E-cig users (E-cig), waterpipe smokers (WP) and dual smokers (CSWP) using GeneChip™ WT Pico kit for transcriptional profiling. We found alterations in a distinct set of lncRNAs among subjects exposed to E-cig vapor, cigarette smoke, waterpipe smoke and dual smoke with some overlaps. Gene enrichment analyses of the differentially expressed lncRNAs demonstrated enrichment in the lncRNAs involved in crucial biological processes including steroid metabolism, cell differentiation and proliferation. Thus, the characterized lncRNA profiles of the plasma-derived exosomes from smokers, vapers, waterpipe users, and dual smokers will help identify the biomarkers relevant to chronic lung diseases such as COPD, asthma or IPF.

E-Cigarette or Vaping Product Use-associated Lung Injury: Developing a Research Agenda. An NIH Workshop Report

The NHLBI convened a working group on October 23, 2019, to identify the most relevant and urgent research priorities and prevailing challenges in e-cigarette or vaping product use-associated lung injury (EVALI). Experts across multiple disciplines discussed the complexities of the EVALI outbreak, identified research priorities, and recommended strategies to address most effectively its causal factors and improve diagnosis, treatment, and prevention of this disease. Many research priorities were identified, including the need to create national and international registries of patients with EVALI, to track accurately those affected and assess outcomes. The group concluded that biospecimens from subjects with EVALI are urgently needed to help define EVALI pathogenesis and that vaping has disease risks that are disparate from smoking, with the occurrence of EVALI highlighting the importance of broadening e-cigarette research beyond comparators to smoking-related diseases.

Acute Eosinophilic Pneumonia Due to Vaping-Associated Lung Injury

A case is described of a 29-year-old female who presented with acute hypoxic respiratory failure due to acute eosinophilic pneumonia, associated with the use of electronic cigarettes to vape tetrahydrocannabinol (THC), together with the contemporary clinical understanding of the syndrome of electronic-cigarette associated lung injury (EVALI). Attention is drawn to acute eosinophilic pneumonia as a potential consequence of vaping-associated lung injury to understand the diagnostic evaluations and therapeutic interventions for acute eosinophilic pneumonia associated with vaping THC.

E-cigarette use and respiratory disorders: an integrative review of converging evidence from epidemiological and laboratory studies

BACKGROUND

Use of electronic cigarettes (e-cigarettes) is prevalent among adolescents and young adults, but there has been limited knowledge about health consequences in human populations. We conduct a systematic review and meta-analysis of results on respiratory disorders from studies of general-population samples and consider the mapping of these results to findings about biological processes linked to e-cigarettes in controlled laboratory studies.

METHOD

We conducted a literature search and meta-analysis of epidemiological studies on the association of e-cigarette use with asthma and with COPD. We discuss findings from laboratory studies about effects of e-cigarettes on four biological processes: cytotoxicity, oxidative stress/inflammation, susceptibility to infection and genetic expression.

RESULTS

Epidemiological studies, both cross-sectional and longitudinal, show a significant association of e-cigarette use with asthma and COPD, controlling for cigarette smoking and other covariates. For asthma (n=15 studies), the pooled adjusted odds ratio (aOR) was 1.39 (95% CI 1.28-1.51); for COPD (n=9 studies) the aOR was 1.49 (95% CI 1.36-1.65). Laboratory studies consistently show an effect of e-cigarettes on biological processes related to respiratory harm and susceptibility to illness, with e-cigarette conditions differing significantly from clean-air controls, although sometimes less than for cigarettes.

CONCLUSIONS

The evidence from epidemiological studies meets established criteria for consistency, strength of effect, temporality, and in some cases a dose-response gradient. Biological plausibility is indicated by evidence from multiple laboratory studies. We conclude that e-cigarette use has consequences for asthma and COPD, which is of concern for respirology and public health.

All up in smoke: vaping-associated lung injury

The electronic cigarette (EC), was initially introduced as a safe alternative to conventional cigarette smoking While initially seemingly innocuous, over 2800 E-cigarette, or Vaping, product use-associated lung injury (EVALI) cases have been reported in the USA, with a spectrum of clinical severity ranging from mild dyspnea to overt respiratory failure In this report we highlight three EVALI cases whom presented with dyspnea and a variety of non-specific symptoms. Diagnostic imaging demonstrated bilateral reticular infiltrates and ground-glass opacities with lymphadenopathy. Clinically, patients failed to respond to empiric antibiotics but improved after initiating steroids. Consistent with prior case series, our patients reported exposure to EC liquids containing tetrahydrocannabinol (THC)/cannabidiols (CBD) additives, suggesting Vitamin E acetate as the potentially harmful constituent. In this case series and review, we not only summarize prior clinical studies that have evaluated the effects of vaping on cardiopulmonary function as well as case reports on EVALI, but also discuss the pathophysiology of vaping and EVALI. It remains unclear not only why some individuals develop EVALI, but why the clinical and pathological presentations vary. EVALI remains a significant public health concern and clinicians must maintain a high index of suspicion for this novel phenomenon.

Electronic-Cigarette Vehicles and Flavoring Affect Lung Function and Immune Responses in a Murine Model

The use of electronic nicotine delivery systems (ENDS), also known as electronic-cigarettes (e-cigs), has raised serious public health concerns, especially in light of the 2019 outbreak of e-cig or vaping product use-associated acute lung injury (EVALI). While these cases have mostly been linked to ENDS that contain vitamin E acetate, there is limited research that has focused on the chronic pulmonary effects of the delivery vehicles (i.e., without nicotine and flavoring). Thus, we investigated lung function and immune responses in a mouse model following exposure to the nearly ubiquitous e-cig delivery vehicles, vegetable glycerin (VG) and propylene glycol (PG), used with a specific 70%/30% ratio, with or without vanilla flavoring. We hypothesized that mice exposed sub-acutely to these e-cig aerosols would exhibit lung inflammation and altered lung function. Adult female C57BL/6 mice (n = 11-12 per group) were exposed to filtered air, 70%/30% VG/PG, or 70%/30% VG/PG with a French vanilla flavoring for 2 h a day for 6 weeks. Prior to sacrifice, lung function was assessed. At sacrifice, broncho-alveolar lavage fluid and lung tissue were collected for lipid mediator analysis, flow cytometry, histopathology, and gene expression analyses. Exposures to VG/PG + vanilla e-cig aerosol increased lung tidal and minute volumes and tissue damping. Immunophenotyping of lung immune cells revealed an increased number of dendritic cells, CD4+ T cells, and CD19+ B cells in the VG/PG-exposed group compared to air, irrespective of the presence of vanilla flavoring. Quantification of bioactive lung lipids demonstrated a >3-fold increase of 2-arachidonoylglycerol (2-AG), an anti-inflammatory mediator, and a 2-fold increase of 12-hydroxyeicosatetraenoic acid (12-HETE), another inflammatory mediator, following VG/PG exposure, with or without vanilla flavoring. This suggests that e-cig aerosol vehicles may affect immunoregulatory molecules. We also found that the two e-cig aerosols dysregulated the expression of lung genes. Ingenuity Pathway Analysis revealed that the gene networks that are dysregulated by the VG/PG e-cig aerosol are associated with metabolism of cellular proteins and lipids. Overall, our findings demonstrate that VG and PG, the main constituents of e-liquid formulations, when aerosolized through an e-cig device, are not harmless to the lungs, since they disrupt immune homeostasis.

Three Patients With Acute Pulmonary Damage Following the Use of E-Cigarettes-A Case Series

BACKGROUND

The use of e-cigarettes is on the rise around the world. Many case reports of acute lung injury due to e-cigarette use have been published in recent months in the USA, but no comparable cases have emerged in Germany up to the present report. The use of e-cigarettes has risen very rapidly in the USA in recent years, simultaneously with the legalization of marijuana sale in many American states. Most of the cases described there involved the use, not only of nicotine, but of tetrahydrocannabinol (THC, the psychoactive ingredient in marijuana) as well, though some of the patients had indeed not used additives (e.g. THC).

METHODS

We report three cases in Germany of acute pulmonary illness that we consider to have been caused by the use of e-cigarettes.

RESULTS

All three patients were hospitalized for acute shortness of breath. Two displayed partial respiratory insufficiency and bilateral pulmonary infiltrates. All three stated that they had used ordinary, commercially available e-cigarettes every day for at least the past three months. In the first patient, a 48-year-old man, the complete blood count and bronchial lavage findings indicated eosinophilic inflammation. The second patient, a 22-year-old man, developed multiple episodes of hemoptysis, with computed tomography (CT) showing diffuse alveolar bleeding; his complete blood count also revealed eosinophilic inflammation. The third patient, a 34-year-old man, displayed acute ground-glass lung opacities as well as fibrosing changes on CT corresponding to pulmonary sarcoidosis. All three recovered on high-dose systemic corticosteroid treatment and were discharged from the hospital in 2 to 12 days.

CONCLUSION

In the first two cases, acute pulmonary injury was very likely due to e-cigarette consumption, as all other possible causes were ruled out. A possible link to e-cigarette use was present in the third case. We thus describe the first three suspected cases of acute lung disease due to e-cigarette use in Germany. These patients do not share any common, typical clinical picture; rather, their symptoms represent different components of the wide spectrum of interstitial lung disease. A uniform national registry should be established to improve our understanding of the adverse effects of e-cigarettes and the resulting acute and chronic changes in the lungs.

Histologic patterns of lung injury in patients using e-cigarettes

In recent years, e-cigarette use has become more popular. Until recently, it was considered safer than smoking. We report two cases of acute pulmonary illness associated with vaping, focusing on their histologic patterns.

Clinical Features of E-cigarette, or Vaping, Product Use-Associated Lung Injury in Teenagers

BACKGROUND

In the United States in 2019, there was an outbreak of electronic cigarette, or vaping, product use-associated lung injury (EVALI). The manifestations of EVALI in adolescents are not well characterized. We describe the diagnosis, evaluation, and management of EVALI in adolescents hospitalized at a tertiary care, university-affiliated children's hospital.

METHODS

A multidisciplinary committee developed an EVALI algorithm on the basis of guidelines from the Centers for Disease Control and Prevention. A retrospective chart review was conducted on patients diagnosed with EVALI. Descriptive analyses included sociodemographic characteristics, clinical presentation, laboratory and imaging results, pulmonary function testing, oxygen requirements, and clinic follow-up.

RESULTS

Thirteen hospitalized adolescents were diagnosed with confirmed or probable EVALI. The majority were female (54%) with a mean age of 15.9 years. Sixty-nine percent of patients presented with respiratory symptoms, whereas gastrointestinal symptoms were prominent in 85% of patients. Vaping Δ-9-tetrahydrocannabinol was reported in 92% of patients, and vaping nicotine was reported in 62% of patients. All had bilateral ground-glass opacities on the chest computed tomography (CT) scan. Treatment with glucocorticoids led to clinical improvement in 11 of 12 patients. Treatment with glucocorticoids led to improvement in both forced expiratory volume in 1 second and forced vital capacity (P < .05). Four patients required home oxygen on the basis of 6-minute walk test results.

CONCLUSIONS

Diagnosis of EVALI should be suspected on the basis of vaping history and clinical presentation. Glucocorticoid treatment led to an improvement in symptoms and lung function. The 6-minute walk test may help determine oxygen needs at discharge.

EVALI and the Pulmonary Toxicity of Electronic Cigarettes: A Review

Electronic cigarettes are a novel and emerging product increasingly used by the general public. However, despite their popularity, they remain poorly studied and with likely serious health risks. EVALI, or "electronic cigarette or vaping product use-associated lung injury," is a recently described entity at the forefront of current investigations. Though EVALI has been linked to vitamin E acetate, a constituent of THC vaping products, electronic cigarettes likely pose a host of other pulmonary toxicities. The presentation, diagnostic work-up, treatment, and pathophysiology of EVALI are herein described, as well as the general pulmonary toxicity profile of electronic cigarettes.

Electronic cigarette vapour moderately stimulates pro-inflammatory signalling pathways and interleukin-6 production by human monocyte-derived dendritic cells

Dendritic cells (DCs) are professional antigen presenting cells that play a critical role in bridging innate and adaptive immunity. Numerous studies have shown that tobacco constituents present in conventional cigarettes affect the phenotype and function of DCs; however, no studies have examined the effects of vapour from E-cigarettes on human DCs. Here, the effects of E-cigarette vapour extract (ECVE) on the phenotype and function of DCs were investigated by creating an in vitro cell culture model using human monocyte-derived DCs (MoDCs). Immature DCs were generated from peripheral blood monocytes and mature DCs were then produced by treatment with LPS or Poly I:C for 24 h. For LPS-matured DCs, 3% ECVE treatment slightly suppressed HLA-DR and CD86 expression, whereas 1% ECVE treatment enhanced IL-6 production. The overall expression of 29 signalling molecules and other cytoplasmic proteins (mainly associated with DC activation) was significantly upregulated in immature DCs by 1% ECVE, and in LPS-treated DCs by 3% ECVE. In particular, the condition that induced IL-6 production also upregulated MAPK pathway activation. These findings indicate that E-cigarette vapour moderately affects human DCs, but the effects are less pronounced than those reported for tobacco smoke.

Case series: Adolescent victims of the vaping public health crisis with pulmonary complications

Alongside the epidemic use of electronic cigarettes (e-cigarettes) across the country, evidence of multiple pulmonary complications has emerged, with the most immediately life-threatening being the new clinical condition of e-cigarette/vaping-associated lung injury (EVALI), with investigation actively underway to further define this entity and determine the cause or causes. We present a series of cases of respiratory illnesses associated with e-cigarette use, many of which meet criteria for suspected or confirmed EVALI, managed at a pediatric tertiary care center, demonstrating notable variation in presenting symptoms and severity. Most cases improved with supportive respiratory care and the administration of corticosteroids and antibiotics, although generally no infection was found. The cases also tend to show improvement with discontinuation of the use of e-cigarettes. We discuss challenges in determining the contribution of e-cigarettes to the case pathology and review possible diagnostic and treatment options. In patients suffering from e-cigarette-related respiratory illness including EVALI, the primary treatment goal should be the cessation of e-cigarette use and avoidance of other possible pulmonary toxins, including conventional cigarettes. Prevention of e-cigarette use is critical in the youth population, as these patients are typically nicotine naïve and do not engage in smoking conventional cigarettes before initiation of vaping.

A Systematic Literature Review of E-Cigarette-Related Illness and Injury: Not Just for the Respirologist

Following the recent electronic cigarette (e-cigarette) illness outbreak, the current review aimed to collect all related clinical cases for study and analysis and provide a critical synopsis of the proposed injury mechanism. Adhering to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analysis) guidelines, e-cigarette-related clinical cases were identified via Google Scholar and PubMed databases. Additionally, references of published case reports and previous review papers were manually searched, revealing 159 publications presenting e-cigarette-related case reports and 19 reports by the Centers for Disease Control and Prevention. 238 individual cases were identified; 53% traumatic injuries due to e-cigarette explosion or self-combustion, 24% respiratory cases, and 12% poisonings. Additional cases pertained to oral, cardiovascular, immunologic, hematologic, allergic reactions, infant complications, and altered medication levels. Case reports were mainly published between 2016-2019 (78%). The oldest case, a lipoid pneumonia, was published in 2012. The current review showed that e-cigarette-related health effects extend beyond the acute lung injury syndrome, including traumatic, thermal injuries and acute intoxications. Physicians should be aware of the distinct clinical presentations and be trained to respond and treat effectively. Regulators and public health authorities should address the regulatory gap regarding electronic nicotine delivery systems (ENDS) and novel tobacco products.

Pulmonary Illness Related to E-Cigarette Use in Illinois and Wisconsin - Final Report

BACKGROUND

E-cigarettes are battery-operated devices that heat a liquid and deliver an aerosolized product to the user. Pulmonary illnesses related to e-cigarette use have been reported, but no large series has been described. In July 2019, the Wisconsin Department of Health Services and the Illinois Department of Public Health received reports of lung injury associated with the use of e-cigarettes (also called vaping) and launched a coordinated public health investigation.

METHODS

We defined case patients as persons who reported use of e-cigarette devices and related products in the 90 days before symptom onset and had pulmonary infiltrates on imaging and whose illnesses were not attributed to other causes. Medical record abstraction and case patient interviews were conducted with the use of standardized tools.

RESULTS

There were 98 case patients, 79% of whom were male; the median age of the patients was 21 years. The majority of patients presented with respiratory symptoms (97%), gastrointestinal symptoms (77%), and constitutional symptoms (100%). All case patients had bilateral infiltrates on chest imaging. A total of 95% of the patients were hospitalized, 26% underwent intubation and mechanical ventilation, and two deaths were reported. A total of 89% of the patients reported having used tetrahydrocannabinol products in e-cigarette devices, although a wide variety of products and devices was reported. Syndromic surveillance data from Illinois showed that the mean monthly rate of visits related to severe respiratory illness in June through August of 2019 was twice the rate that was observed in the same months in 2018.

CONCLUSIONS

Case patients presented with similar clinical characteristics. Although the definitive substance or substances contributing to injury have not been determined, this initial cluster of illnesses represents an emerging clinical syndrome or syndromes. Additional work is needed to characterize the pathophysiology and to identify the definitive causes.

E-cigarette, or vaping, product use-associated lung injury in adolescents: a review of imaging features

BACKGROUND

There has been a recent increase in recognition of lung disease related to the use of electronic cigarettes (called "vaping"). These patients present with acute respiratory illness following exposure to vaporized cannabis or nicotine products and sometimes require hospitalization and intensive care. We describe the imaging findings of this disease entity in the pediatric population.

OBJECTIVE

To describe the radiologic findings of lung injury associated with electronic cigarette use (vaping) in the adolescent pediatric population.

MATERIALS AND METHODS

We identified all adolescents with acute respiratory illness and a history of electronic cigarette use who presented at our institution within a 3-month period (June 2019 through August 2019). We excluded adolescents with potential intercurrent pulmonary disease. We reviewed the charts for symptomatology and laboratory and pathology data. In addition, we reviewed the chest radiographs and chest CTs of these adolescents.

RESULTS

The review group consisted of 12 teenage pediatric patients (10 boys and 2 girls; mean age 16.9 years, range 16.0-17.7 years) with acute respiratory illness found to have a temporal association with electronic cigarette use for cannabis products, nicotine, or both. Other etiologies for illness in these adolescents had been excluded by clinical and laboratory evaluation. All of the adolescents were admitted to the hospital for treatment. The clinical presentations included dyspnea, abdominal pain and constitutional symptoms. Pulmonary function testing that was performed in all patients during admission or follow-up demonstrated reduced diffusion capacity in 4/12 (33%), an obstructive ventilatory pattern in 4/12 (33%), a restrictive pattern in 1/12 (8%), and a mixed obstructive and restrictive pattern in 2/12 (17%) adolescents. Bronchoalveolar lavage studies, performed in 9 of the 12 adolescents, revealed inflammatory cells and lipid-laden macrophages. All of the patients underwent CT of the chest; the findings were notable for centrilobular ground-glass nodules (11/12; 92%) and confluent ground-glass opacities (12/12; 100%), with frequent subpleural sparing (9/12; 75%). Additionally, 6/12 (50%) adolescents demonstrated small pleural effusions; 6/12 (50%) had mild bronchial wall thickening; 9/12 (75%) had enlarged hilar or mediastinal lymph nodes; and 2/12 (17%) had a small pericardial effusion.

CONCLUSION

As seen in our teenage population, e-cigarette, or vaping, product use-associated lung injury (EVALI) is characterized by centrilobular ground-glass nodules and ground-glass opacities with subpleural sparing. The imaging findings are most consistent with acute lung injury resulting from toxic inhalation. Because adolescent pediatric patients might not be forthcoming with their history of electronic cigarette use, it is important for the pediatric radiologist to be aware of the imaging patterns of this disease.

[E-Cigarettes - Operating Principle, Ingredients, and Associated Acute Lung Injury]

Beginning in April of 2019, the US saw > 2,000 cases of hospitalized, often young, patients with severe acute lung injury, of which over 40 died, and the only existing connection between patients was their use of electronic cigarettes (e-cigarettes). The acronym EVALI ("e-cigarette, or vaping, product use associated lung injury") has since been established for the condition. This review article is intended to provide an overview of recent, mainly US literature on EVALI, including the case definition, epidemiology, clinical presentation, typical disease progression, as well as potential triggers. Ancillary to this, the review further provides a general overview of the basic function of e-cigarettes, the ingredients of the liquids used in these (e-liquids), as well as a brief description of the associated potential inhalation risks.

Discordant bilateral bronchoalveolar lavage findings in a patient with acute eosinophilic pneumonia associated with counterfeit tetrahydrocannabinol oil vaping

Vaping has emerged as a popular alternative form of inhalation of nicotine and marihuana derivates (including Tetrahydrocannabinol, THC) in part due to the avoidance of combustion byproducts. Unfortunately, THC oil (especially that produced by unregulated individuals) may contain dilutants such as propylene glycol, vitamin E, and flavoring ingredients that can lead to adverse respiratory effects. Acute eosinophilic pneumonia (AEP) has been described in association with e-cigarette and vaping associated lung injury (EVALI) but the majority of bronchoalveolar lavage (BAL) samples reported in the literature do not show eosinophils as the predominant cell lineage. Only two other cases of AEP have been published, and here we present the first case reported in the literature of a patient with EVALI with AEP pattern associated with counterfeit tetrahydrocannabinol (THC) oil vaping and discordant bilateral BAL cell count differential.

Lung Injury Associated with E-Cigarette or Vaping Product Use

In the United States, an epidemic of unusual and severe lung disease associated with the use of e-cigarettes, or vaping, began in spring 2019. By fall 2019, the US Centers for Disease Control and Prevention had received reports of e-cigarette or vaping product use-associated lung injury (EVALI) cases from all state health departments in the continental US, Hawaii, and the US Virgin Islands. According to the cases, a number of young people had developed severe lung disease characterized by marked shortness of breath and cough. Constitutional and gastrointestinal symptoms are common. Clinical laboratory test results in EVALI are often consistent with nonspecific findings of pulmonary/systemic inflammation. Many reported cases of EVALI have required critical care interventions including noninvasive positive airway pressure, cardiotonic pressors, and intubation/mechanical ventilation. The need for extracorporeal membrane oxygenation support has been reported in some cases. The lung disease is diffuse and has multiple pathologies. Patients are often treated with intravenous or oral corticosteroids with clinical improvement, although the natural history of the disease remains unknown. In rare cases, the outcome is fatal. This article reviews the epidemiology, clinical presentation, radiographic appearance, diagnostic approach, and treatment regimens for patients with vaping-induced lung disease as noted in multiple patients and the current literature. [Pediatr Ann. 2020;49(2):e93-e98.].

Vaping-Associated Respiratory Distress Syndrome: Case Classification and Clinical Guidance

Exposure to vaping is associated with a growing list of respiratory syndromes including an acute progressive form with life-threatening hypoxemic respiratory failure and pathologic changes of lung injury termed vaping-associated respiratory distress syndrome.

DATA SOURCES

Center from Disease Control, Departments of Public Health, MEDLINE (via PubMed), and the Cochrane Library.

STUDY SELECTION DATA EXTRACTION AND DATA SYNTHESIS

Cases, series, and public health reports of cases that met the Centers for Disease Control and Prevention case definition of vaping-associated respiratory disease were extracted by an author with perfect verification by a second. Cases were classified on the basis of toxin exposure, symptoms, oxygen saturation, progression to respiratory failure, and pathologic features, and a clinically actionable system of classification was based on expert opinion.

CONCLUSIONS

The reported spectrum of vaping-associated respiratory diseases allows clinical classification of cases into groups with distinct evaluation, management, and recommendations for prevention and follow-up. Clinical stratification also identifies a small proportion of vaping-exposed patients who are at risk for progression to hypoxemic respiratory failure and an acute respiratory distress syndrome-like illness.

Life-threatening bronchiolitis related to electronic cigarette use in a Canadian youth

BACKGROUND

Although electronic cigarettes (e-cigarettes) were initially marketed as a potential smoking-cessation aid and a safer alternative to smoking, the long-term health effect of e-cigarette use ("vaping") is unknown. Vaping e-liquids expose the user to several potentially harmful chemicals, including diacetyl, a flavouring compound known to cause bronchiolitis obliterans with inhalational exposure ("popcorn worker's lung").

CASE DESCRIPTION

We report the case of a 17-year-old male who presented with intractable cough, progressive dyspnea and malaise after vaping flavoured e-liquids and tetrahydrocannabinol intensively. Initial physical examination showed fever, tachycardia, hypoxemia, and bibasilar inspiratory crackles on lung auscultation. Computed tomography of the chest showed diffuse centrilobular "tree-inbud" nodularity, consistent with acute bronchiolitis. Multiple cultures, including from 2 bronchoalveolar lavage samples, and biopsy stains, were negative for infection. He required intubation, invasive mechanical ventilation and venovenous extracorporeal membrane oxygenation (ECMO) for refractory hypercapnia. The patient's condition improved with high-dose corticosteroids. He was weaned off ECMO and mechanical ventilation, and discharged home after 47 days in hospital. Several months after hospital discharge, his exercise tolerance remained limited and pulmonary function tests showed persistent, fixed airflow obstruction with gas trapping. The patient's clinical picture was suggestive of possible bronchiolitis obliterans, thought to be secondary to inhalation of flavouring agents in the e-liquids, although the exact mechanism of injury and causative agent are unknown.

INTERPRETATION

This case of severe acute bronchiolitis, causing near-fatal hypercapnic respiratory failure and chronic airflow obstruction in a previously healthy Canadian youth, may represent vaping-associated bronchiolitis obliterans. This novel pattern of pulmonary disease associated with vaping appears distinct from the type of alveolar injury predominantly reported in the recent outbreak of cases of vaping-associated pulmonary illness in the United States, underscoring the need for further research into all potentially toxic components of e-liquids and tighter regulation of e-cigarettes.

Electronic cigarettes: where to from here?

Although the usage of electronic (e)-cigarettes (EC) and similar devices has gained in popularity as an apparent smoking cessation strategy, serious concerns are emerging in relation to both the efficacy of this strategy, as well as the inappropriate use of these devices. While the comparative safety of e-cigarettes is based on the reasonable contention that the levels of inhaled toxicants present in the aerosols generated by these devices are considerably lower than those present in tobacco smoke, the perception that they are indeed relatively risk-free is being challenged on several fronts. Notwithstanding lack of convincing evidence of efficacy as a superior smoking cessation strategy, foremost among emerging concerns is the increasing use of electronic nicotine-delivery devices by young never-smokers. Other concerns include increasing levels of sophistication in the design and capacity of these devices in relation to nicotine content and delivery, the potential threat of manipulation of the contents of e-liquids, as well as other additives such as illicit drugs and other potentially toxic agents that can be vaporised. These issues, together with the potential risks to respiratory health, specifically "e-cigarette or vaping product use-associated lung injury" represent the major thrusts of this review.

The First Case of E-Cigarette-Induced Polycythemia

A 71-year-old male smoker was referred to our hospital because of increased hemoglobin and hematocrit. At initial consultation, his hemoglobin and hematocrit levels were 21.8 g/dl and 64.8%, respectively. Other laboratory data and his cardiopulmonary functions were almost normal, and JAK2 V617F mutation was negative. He had smoked about 25 cigarettes per day for 50 years until the age of 70, when he switched from conventional smoking to electronic cigarettes (e-cigarettes). We requested that he quit e-cigarette use. Thereafter, his hemoglobin and hematocrit gradually decreased and normalized. Here, we report the first case of e-cigarette-induced polycythemia.

Preoperative vaping prevalence and behavior of French surgical patients: A multicentre study

INTRODUCTION

Prevalence and tobacco-related perioperative complications have been largely reported. The impact of vaping (e-cigarette use) on the perioperative period has been rarely evaluated. The purpose of this multicentre cross-sectional survey was to assess the prevalence of vaping and behaviour of patients undergoing elective surgery.

METHODS

After institutional review board committee and patient approvals, patients (aged ≥18 years) scheduled for elective non-cardiac surgery in six French hospitals were assessed preoperatively. Demographic characteristics, and information on vaping, smoking or dual-use status and consumption were reported.

RESULTS

In six centres, 1712 eligible patients were approached and 1664 patients were included in this study from June 2016 to January 2017. Of these, 62 patients used e-cigarettes in the preoperative period (3%; 95% CI: 2–4), including 24 exclusive e-cigarette users (1%; 95% CI: 1–2), 38 dual-users (2%; 95% CI: 2–3) and 365 smokers (22%; 95% CI: 20–24). Vapers were older than smokers (53 vs 47 years old; p=0.01). During the preoperative period, 12 patients (1%) reported vaping the morning of surgery.

CONCLUSIONS

In the preoperative period, vaping was ten-fold less prevalent than smoking. Although the clinical relevance may be weak, further research is needed to explore the real impact of vaping on patients’ outcomes and to elaborate on clinical recommendations.

A Case Report of Secondary Spontaneous Pneumothorax Induced by Vape

Electronic cigarettes (referred here as E-cigarettes or vapes) are devices that contain heated nicotine/cannabinol vaporized aerosol solution for consumption. While long-term toxicities of E-cigarettes are unknown, the acute adverse events of vaping that have occurred are concerning. There have been variations of pneumonitis presentations so far, however, very few case reports have been shown to have a complication of a pneumothorax. We hereby present a case of a 35-year-old male who presented with spontaneous pneumothorax and pneumonitis due to vaping.

Vaping Associated Lung Injury (EVALI): An Explosive United States Epidemic

As of November 5, 2019, there have been 2051 cases of e-cigarette, or vaping, product use associated lung injury (EVALI), with 39 deaths reported in the United States, over four months. The rapidly increasing popular habits of vaping and e-cigarette use has suddenly turned deadly in the United States. This epidemic of vaping-associated illness appears to be limited to the United States with few reported cases and no deaths from the rest of the world.

Electronic Cigarette or Vaping-associated Lung Injury (EVALI): The Tip of the Iceberg

The Centers for Disease Control and Prevention, the U.S. Food and Drug Administration, and state and local health departments have begun an investigation into the lung injury attributed to the use of electronic cigarette (e-cigarette) or vaping products. A clinical case of a 24-year-old man who used e-cigarette products regularly and presented with shortness of breath, productive cough, chest pain, and fever for 1 week was discussed. Radiographic and CT findings in that patient were reviewed. Recent cases of e-cigarette-associated lung injury from the literature were summarized to continue the dialogue and encourage radiologists to research this relatively new and specific type of lung injury. © RSNA, 2019.

Vaping-Associated Acute Respiratory Failure Due to Acute Lipoid Pneumonia

Electronic cigarettes, pens, cartridges and other devices were developed as nicotine delivery systems not requiring combustion of tobacco leaves. This technology was subsequently employed to deliver the cannabis component tetrahydrocannabinol (THC) via products often manufactured without adequate quality oversight and sold illegally. Recently, five patients presenting within a 2-month period with acute respiratory failure due to acute lipoid pneumonia after inhaling THC-containing concentrates or oils have been described. We report a 28-year-old previously healthy man who presented in acute respiratory failure 2 weeks after initiating use of a street-purchased THC-containing vape cartridge. Bronchoalveolar lavage cytology with oil red O staining confirmed the diagnosis of acute lipoid pneumonia. Diffuse alveolar hemorrhage and eosinophilic pneumonia were excluded. Evolving evidence supports a clinical entity of acute respiratory failure due to acute, exogenous lipoid pneumonia induced by THC-containing concentrates or oils inhaled through a variety of vaping products. All six patients reported to date received intravenous corticosteroids and survived to hospital discharge.