Giant cell interstitial pneumonia: case series with comprehensive ultrastructural analyses of "not only" hard metal pneumoconiosis

AIMS

Giant cell interstitial pneumonia (GIP) is a fibrosing lung disease histologically characterized by centrilobular pulmonary fibrosis and cannibalistic intra-alveolar multinucleated giant cells. It is considered a form of pneumoconiosis caused particularly by secondary exposure to hard metals (cemented carbide or tungsten carbide). Hard metals are commonly used in various industrial applications, such as cutting tools, drilling tools, machine inserts, and other wear-resistant components. However, cases with unknown exposure that recurred in transplanted lungs have been described. This has led to the hypothesis of a complex etiopathogenesis, likely multifactorial, involving the coparticipation of immune mechanisms. We aimed to identify all the elements present in a series of GIP lung samples to better understand the pathogenic mechanisms of the disease.

METHODS AND RESULTS

We describe five cases of histologically diagnosed GIP in patients with occupational exposure to metallic dust using ultrastructural characterization to identify metal dust and to quantify asbestos fibres. We found that tungsten was present in three cases, albeit in trace amounts in two of them. Numerous elements were identified in all samples, including asbestos fibres in patients with endstage pulmonary fibrosis. Furthermore, in one of the described cases the recurrence of the disease was also observed in transplanted lungs.

CONCLUSION

These findings support the hypothesis that GIP may be due to elements other than hard metals, with asbestos possibly representing a contributory factor in the expression of a more severe fibrotic disease. The recurrence of GIP observed in transplanted organs strengthens the hypothesis of the existence of a not yet fully understood etiopathogenic immune mechanism.

E-cigarette, or Vaping, Product Use Associated Lung Injury: Epidemiology, Challenges, and Implications With COVID-19

BACKGROUND

E-cigarette, or vaping products produce an aerosol by heating nicotine, or cannabis including tetrahydrocannabinol (THC) and cannabidiol (CBD), mixed with other chemicals that help make the aerosol. They are increasingly popular among teenagers and young adults, with a 2023 survey reporting that 2.13 million middle and high school students in the United States used e-cigarettes within the last 30 days. The use of e-cigarette, or vaping products could lead to an acute pulmonary inflammatory syndrome called e-cigarette, or vaping, product use-associated lung injury (EVALI). We review the challenges in diagnosing and treating EVALI, especially during the COVID-19 pandemic.

METHODS

We conducted a literature search on June 10, 2024 using the PubMed database. We searched for articles, case reports and CDC reports investigating the pathogenesis, treatment, and challenges of diagnosing EVALI during the COVID-19 pandemic.

RESULTS

The exact causes of EVALI are not completely understood, although it has been linked to the use of THC and vitamin E acetate. There are no specific biomarkers to diagnose EVALI and it is typically diagnosed through a process of eliminating other possible conditions. Eight studies detailed cases where pediatric patients were initially diagnosed with COVID-19 or community-acquired pneumonia, despite multiple negative COVID-19 tests, and were later found to have EVALI.

CONCLUSIONS

After alerting the public about the removal of vitamin E acetate from vape liquids in 2020, there has been a decline in cases of EVALI, although they are still detected. Therefore, it is necessary to continue looking for diagnostic markers of EVALI and further investigate the toxicity of vapes and e-cigarettes to prevent the recurrence of another EVALI epidemic, especially among teenagers and young adults.

Spectrum of Thoracic Imaging Findings in the Setting of Substance Abuse

ABSTRACT

Substance abuse continues to be prevalent nationwide and can lead to a myriad of chest pathologies. Imaging findings are vast and can include nodules, masses, ground-glass opacities, airspace disease, and cysts. Radiologists with awareness of these manifestations can assist in early identification of disease in situations where information is unable to be obtained from the patient. This review focuses on thoracic imaging findings associated with various forms of substance abuse, which are organized by portal of entry into the thorax: inhalation, ingestion, and injection.

Uncommon Causes of Interlobular Septal Thickening on CT Images and Their Distinguishing Features

Interlobular septa thickening (ILST) is a common and easily recognized feature on computed tomography (CT) images in many lung disorders. ILST thickening can be smooth (most common), nodular, or irregular. Smooth ILST can be seen in pulmonary edema, pulmonary alveolar proteinosis, and lymphangitic spread of tumors. Nodular ILST can be seen in the lymphangitic spread of tumors, sarcoidosis, and silicosis. Irregular ILST is a finding suggestive of interstitial fibrosis, which is a common finding in fibrotic lung diseases, including sarcoidosis and usual interstitial pneumonia. Pulmonary edema and lymphangitic spread of tumors are the commonly encountered causes of ILST. It is important to narrow down the differential diagnosis as much as possible by assessing the appearance and distribution of ILST, as well as other pulmonary and extrapulmonary findings. This review will focus on the CT characterization of the secondary pulmonary lobule and ILST. Various uncommon causes of ILST will be discussed, including infections, interstitial pneumonia, depositional/infiltrative conditions, inhalational disorders, malignancies, congenital/inherited conditions, and iatrogenic causes. Awareness of the imaging appearance and various causes of ILST allows for a systematic approach, which is important for a timely diagnosis. This study highlights the importance of a structured approach to CT scan analysis that considers ILST characteristics, associated findings, and differential diagnostic considerations to facilitate accurate diagnoses.

Metal Concentrations in E-Cigarette Aerosol Samples: A Comparison by Device Type and Flavor

BACKGROUND

The rapid evolution of electronic cigarette (e-cigarette) products warrants surveillance of the differences in exposure across device types-modifiable devices (MODs), cartridge ("pod")-containing devices (PODs), disposable PODs (d-PODs)-and flavors of the products available on the market.

OBJECTIVE

This study aimed to measure and compare metal aerosol concentrations by device type and common flavors.

METHODS

We collected aerosol from 104 MODs, 67 PODs (four brands: JUUL, Bo, Suorin, PHIX), and 23 d-PODs (three brands: ZPOD, Bidi, Stig) via droplet deposition in a series of conical pipette tips. Metals and metalloids [aluminum (Al), arsenic (As), cobalt (Co), chromium (Cr), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), antimony (Sb), tin (Sn), and zinc (Zn)] were measured using inductively coupled plasma mass spectrometry (ICP-MS), results were log-transformed for statistical analysis, and concentrations are reported in aerosol units (mg / m 3 ).

RESULTS

Of the 12 elements analyzed, concentrations were statistically significantly higher in MOD devices, except for Co and Ni, which were higher in PODs and d-PODs. Of the POD brands analyzed, PHIX had the highest median concentrations among four metals (Al, Ni, Pb, and Sn) compared to the rest of the POD brands. According to POD flavor, seven metals were three to seven orders of magnitude higher in tobacco-flavored aerosol compared to those in mint and mango flavors. Among the d-POD brands, concentrations of four metals (Al, Cu, Ni, and Pb) were higher in the ZPOD brand than in Bidi Stick and Stig devices. According to d-POD flavor, only Cr concentrations were found to be statistically significantly higher in mint than tobacco-flavored d-PODs.

DISCUSSION

We observed wide variability in aerosol metal concentrations within and between the different e-cigarette device types, brands, and flavors. Overall, MOD devices generated aerosols with higher metal concentrations than PODs and d-PODs, and tobacco-flavored aerosols contained the highest metal concentrations. Continued research is needed to evaluate additional factors (i.e., nicotine type) that contribute to metal exposure from new and emerging e-cigarette devices in order to inform policy. https://doi.org/10.1289/EHP11921.

User-generated content and influencer marketing involving e-cigarettes on social media: a scoping review and content analysis of YouTube and Instagram

BACKGROUND

Evidence suggests that experimentation with e-cigarettes among young people is increasing. Social media is widely used by young people with user-generated content and influencer marketing particularly influential in promoting products. This paper documents a snapshot of online user-generated content and influencer marketing related to e-cigarettes on YouTube and Instagram.

METHODS

Scoping review of relevant e-cigarette-related content on two social media platforms popular with youths, YouTube and Instagram, between June and August 2021. Content analysis was undertaken to examine text, audio, and video content, recording age restrictions, health warnings, page characteristics, and post characteristics. Narrative post content was coded using a coding frame that was developed inductively in response to emergent categories.

RESULTS

Vaping was portrayed positively on social media; of the posts analysed, 86.5% (n = 90 of 104) of Instagram posts and 66.0% (n = 64 of 97) of YouTube videos. Warnings about age restrictions and health (e.g., nicotine addiction/toxicity) did not feature in the majority of posts; 43.3% (n = 42) of YouTube videos (n = 42) contained an age warning compared to 20.2% of Instagram posts (n = 21). While 25.8% (n = 25) of YouTube videos and 21.2% of Instagram (n = 22) posts contained a health warning.

CONCLUSION

Of concern is the fact that the vast majority of YouTube and Instagram content about e-cigarettes promoted their use, and typically the content does not contain age and/or health warnings. These findings may highlight a priority for governmental policy to restrict the ability of marketers to reach youths with social media content promoting e-cigarettes.

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.

Imaging of Occupational and Environmental Lung Disease

The respiratory tract is continuously exposed to and filters toxins from the home and work environments. Certain occupations and environmental exposures can cause unique injuries to the upper and lower respiratory system. Despite increasing federal regulations in the workplace, occupation-associated lung disease is still a major cause of lung disease and disability and continues to evolve with changes in industry, regulation, and new emerging exposures and toxins. Establishing a diagnosis can be difficult, often due to long latency between exposure and clinical disease, insufficient patient history, and nonspecific or varying imaging appearance. Identifying key imaging features of occupational lung disease along with a multidisciplinary approach can aid in accurate and timely diagnosis. In this review, we will discuss the importance of a comprehensive patient history, multidisciplinary approach to diagnosis, and key imaging features of occupation-related lung injuries. Radiographic and computed tomographic findings will be described and illustrated.

E-cigarette or vaping product use-associated lung injury: A review of clinico-radio-pathological characteristics

Aggressive, albeit false marketing of electronic nicotine delivery systems (ENDS) or vaping devices as safer alternatives to cigarette smoking, combined with lack of regulations, has led to its mass adoption, especially among youth. A sudden increase in acute lung injuries was noted in 2019 which was linked to ENDS. It was termed by the Centers for Disease Control and Prevention (CDC) as electronic cigarette or vaping product use-associated lung injury (EVALI). Analysis of bronchoalveolar lavage fluid samples linked EVALI to vitamin E acetate (VEA), which is used as a diluting agent for marijuana oils. Patients with EVALI present with a combination of non-specific respiratory, gastrointestinal, and systemic symptoms. Laboratory results may show elevated inflammatory biomarkers. EVALI is a diagnosis of exclusion and must meet the following criteria: i) history of vaping within last 90 days, ii) abnormal chest imaging, iii) negative evaluation for infection, and iv) no other plausible diagnosis. A spectrum of computed tomography (CT) chest findings has been reported in EVALI, ranging from diffuse alveolar damage to organizing pneumonia, characterized by bilateral ground-glass opacities, consolidation, and septal thickening. A similar spectrum is seen on histopathology, characterized by lipid-laden alveolar macrophages, with varying degrees of infiltrative inflammatory cells and fibrin deposition. Early and accurate identification of the EVALI pattern can help optimize patient care. For example, in diffuse alveolar damage (DAD), a lower threshold for ventilation support and corticosteroid may improve outcomes. Here, we review the etiopathogenesis, clinical management, histopathology, and imaging features of EVALI.

Clinical Findings in Adolescents Hospitalized With EVALI; Novel Report on Coagulopathy

OBJECTIVES

Describe clinical characteristics of adolescents hospitalized with e-cigarette or vaping product use-associated lung injury (EVALI) and to investigate association between EVALI and coagulopathy.

METHODS

We conducted a retrospective cohort study of adolescents admitted to the general inpatient or ICUs at 2 major tertiary children's hospitals from January 2019 to June 2021. We included analysis of demographics, clinical findings, laboratory and imaging results, and outcomes.

RESULTS

Forty-four hospitalizations met diagnostic criteria for inclusion per Centers for Disease Control and Prevention guidelines, with 55% of patients admitted after April 2020. Compared with adults, pediatric patients were less likely to present with pulmonary symptoms. Significant laboratory work included elevated white blood cell count of 14.3 k/uL (confidence interval [CI], 13.7-15.0) with neutrophilic predominance, C-reactive protein of 25.2 mg/dL (CI, 22.1-28.2), and erythrocyte sedimentation rate of 66.7 mm/hour (CI, 26.9-76.4). Chest radiographs were poor predictors of disease in 53% of our patients but computed tomography was 100% sensitive. Significant coagulation abnormalities included prothrombin time of 17.7 seconds (CI, 16.4-19.1) and international normalized ratio of 1.54 (CI, 1.43-1.66). Coagulation studies improved with vitamin K and steroid administration. Nine of 16 patients (56%) had abnormal diffusing capacity of the lung for carbon monoxide divided by alveolar volume <80% predicted, suggesting evidence of pulmonary vascular disease, or >100%, suggesting pulmonary hemorrhage.

CONCLUSIONS

EVALI continues to be an important differential diagnosis in the adolescent population. EVALI is likely a result of systemic inflammation with consequences beyond the pulmonary system. The novel report of coagulopathy among adolescents with EVALI in this cohort reveals an opportunity to detect coagulopathy and initiate early therapy.

COVID or Not COVID? A Great Mimicker Behind the Smoke Screen

Vaping is becoming increasingly popular as an alternative to cigarettes. However, vaping does not come without risks; electronic cigarette (e-cigarette) and vaping-associated lung injury (EVALI) is one of the most severe consequences. Coronavirus disease 2019 (COVID-19) and bacterial pneumonia cases often present with almost identical features. We present a case of a young man who presented with pneumonia that was initially thought to be related to COVID-19 infection but later diagnosed as EVALI. Clinicians should have a high suspicion of EVALI in patients who present with hypoxemia and negative infectious workup, particularly during the COVID-19 era. Administration of corticosteroids has shown remarkable efficacy in improving hypoxemia; however, many patients may have chronic lung injury and may require oxygen long-term. Cases of EVALI should continue to be reported and followed up long term for monitoring disease outcomes.

E-cigarette, or vaping, product use Associated Lung Injury (EVALI): new scenarios for physicians and radiologists

A 59-year-old female ex-smoker with 40 pack year smoking history and a 5-year current e-cigarette (EC) use history, presented with progressive dyspnea on exertion and daily cough for 2 months. A CT scan showed a consolidation area with air bronchogram in the middle lobe and non-calcific bilateral nodules, which could be attributed to community-acquired pneumonia. The patient was treated with empiric antibiotics and systemic steroids for 10 days. Infectious, neoplastic and autoimmune pathologies were excluded, whereas a broncho-alveolar lavage revealed an accumulation of lipids in the cytoplasm of the alveolar macrophages. Despite the recommendation of vaping cessation, the patient continued to use EC. A new CT exam, carried out after 18 months, showed reversed halo sign (RHS), patchy ground-glass opacity (GGO), pleuro-parenchymal bands, and indeed perilobular pattern, suggestive of organizing pneumonia (OP). The final diagnosis was E-cigarette, or vaping, product use Associated Lung Injury (EVALI)- related OP.

Electronic Cigarette or Vaping Product Use-Associated Lung Injury in a Previously Healthy Young Male

Vaping (i.e., the use of electronic cigarettes) has been gaining popularity among people for the past few years, perhaps due to the misconception that its use is less harmful than traditional cigarettes. Although the long-term effects of these products are still unknown, it has been shown that they can be implicated in acute lung injury in healthy people. In 2019, an epidemic of severe acute lung injury was reported in the United States, and it was linked to vaping or electronic cigarette use and was referred to as e-cigarette or vaping product use-associated lung injury (EVALI). Here, we present the first case of EVALI in the state of Qatar.

Smoking Addiction and Strategies for Cessation

Cigarette smoking is the leading cause of chronic obstructive pulmonary disease (COPD) worldwide. Smoking cessation is thus integral to the treatment of COPD. Nicotine addiction is a disease dependent on the complex interactions of neurotransmitter pathways, conditioned behaviors, environmental cues, genetic predisposition, and personal life circumstances, which render some more susceptible to tobacco abuse than others. The most successful smoking cessation programs are individualized, comprehensive, and utilize combinations of clinician counseling, behavioral reinforcement, community resources, advanced technology support (eg, smartphone apps, and Internet Web sites), and pharmacotherapy (both nicotine-based and nonnicotine medications). E-cigarettes were introduced to the US market in 2006 and touted as a safer alternative to tobacco cigarette smoking. Unfortunately, over the last 5 to 10 years, recreational e-cigarette use, or "vaping," has increased in popularity, especially among adolescents. This has introduced nicotine addiction to an entire generation of nonsmokers and resulted in numerous cases of acute lung disease, now known as e-cigarette or vape product use-associated lung injury (EVALI). In light of these adverse events, e-cigarettes and vape products are not currently recommended as a smoking cessation aid.

The vaping product use associated lung injury: is this a new pulmonary disease entity?

In the summer of 2019, an epidemic of e-cigarette or vaping product use associated lung injury (EVALI) broke out in the United States of America. EVALI is a lung disease that can be severe and life-threatening. It should be emphasized that EVALI is not a clinical diagnosis, but surveillance case definition. Due to the profile of users of such devices, the pathology mainly affects young adults, although cases of EVALI have been reported in almost all age groups, from teenage children to seniors. The worst prognosis is in patients over 35 years of age, with accompanying diseases. A significant number of patients declared the use of products containing tetrahydrocannabinol (THC). The most likely factor responsible for the occurrence of EVALI is vitamin E acetate, which is sometimes added to liquids necessary for the use of electronic cigarette type devices, especially those liquids that contain THC. Nevertheless, it is possible that other substances used in liquids may also be a causative factor. Typical for EVALI are respiratory, gastrointestinal and systemic symptoms, while in imaging tests, a characteristic feature of EVALI is the presence of opacities on the chest radiogram and ground-glass clouds on computed tomography scans. In the course of this disease, respiratory failure often occurs (58%). In the vast majority of cases oxygen substitution is necessary. Currently, the best treatment of EVALI is considered to be the administration of systemic glucocorticosteroids. Over 90% of patients with EVALI required hospitalization, while the mortality rate was about 2.42%. Median age of the fatalities was 51 years. The aim of this review is to summarise the available information on EVALI and to consider possible causative factors and pathomechanism.

Imaging in Vaping-associated Lung Injury: Beyond the Haze

E-cigarette or vaping, product associated lung injury is a rampant public health issue with a total of 2807 reported hospitalized patients in the United States as of February 18, 2020. Limited data, non-specific symptoms, non-responsiveness to antibiotics, and the lack of a specific biomarker, make it a diagnosis of exclusion. Overlap of clinical and imaging findings with other ongoing respiratory illness (MERS, SARS and COVID-19) poses a challenge in accurate diagnosis. We compiled 3 cases of patients hospitalized with confirmed vaping-associated lung injury and analyzed their imaging patterns, which revealed bilateral consolidation, ground-glass opacities and pleural effusions. We also reviewed the available literature on pathophysiology, imaging findings of EVALI and other respiratory illness.

Chest-CT mimics of COVID-19 pneumonia-a review article

Coronavirus disease 2019 (COVID-19) emerged in early December 2019 in China, as an acute lower respiratory tract infection and spread rapidly worldwide being declared a pandemic in March 2020. Chest-computed tomography (CT) has been utilized in different clinical settings of COVID-19 patients; however, COVID-19 imaging appearance is highly variable and nonspecific. Indeed, many pulmonary infections and non-infectious diseases can show similar CT findings and mimic COVID-19 pneumonia. In this review, we discuss clinical conditions that share a similar imaging appearance with COVID-19 pneumonia, in order to identify imaging and clinical characteristics useful in the differential diagnosis.

CT Findings and Patterns of E-Cigarette or Vaping Product Use-Associated Lung Injury: A Multicenter Cohort of 160 Cases

BACKGROUND

E-cigarette and vaping-induced lung injury (EVALI) causes a spectrum of CT lung injury patterns. Relative frequencies and associations with vaping behavior are unknown.

RESEARCH QUESTION

What are the frequencies of imaging findings and CT patterns in EVALI and what is the relationship to vaping behavior?

STUDY DESIGN AND METHODS

CT scans of 160 subjects with EVALI from 15 institutions were retrospectively reviewed. CT findings and patterns were defined and agreed on via consensus. The parenchymal organizing pneumonia (OP) pattern was defined as regional or diffuse ground-glass opacity (GGO) ± consolidation without centrilobular nodules (CNs). An airway-centered OP pattern was defined as diffuse CNs with little or no GGO, whereas a mixed OP pattern was a combination of the two. Other patterns included diffuse alveolar damage (DAD), acute eosinophilic-like pneumonia, and pulmonary hemorrhage. Cases were classified as atypical if they did not fit into a pattern. Imaging findings, pattern frequencies, and injury severity were correlated with substance vaped (marijuana derives [tetrahydrocannabinol] [THC] only, nicotine derivates only, and both), vaping frequency, regional geography, and state recreational THC legality. One-way analysis of variance, χ² test, and multivariable analyses were used for statistical analysis.

RESULTS

A total of 160 patients (79.4% men) with a mean age of 28.2 years (range, 15-68 years) with EVALI underwent CT scan. Seventy-seven (48.1%), 15 (9.4%), and 68 (42.5%) patients admitted to vaping THC, nicotine, or both, respectively. Common findings included diffuse or lower lobe GGO with subpleural (78.1%), lobular (59.4%), or peribronchovascular (PBV) sparing (40%). Septal thickening (50.6%), lymphadenopathy (63.1%), and CNs (36.3%) were common. PBV sparing was associated with younger age (P = .02). Of 160 subjects, 156 (97.5%) had one of six defined patterns. Parenchymal, airway-centered, and mixed OP patterns were seen in 89 (55.6%), 14 (8.8%), and 32 (20%) patients, respectively. Acute eosinophilic-like pneumonia (six of 160, 3.8%), DAD (nine of 160, 5.6%), pulmonary hemorrhage (six of 160, 3.8%), and atypical (four of 160, 2.5%) patterns were less common. Increased vaping frequency was associated with more severe injury (P = .008). Multivariable analysis showed a negative association between vaping for > 6 months and DAD pattern (P = .03). Two subjects (1.25%) with DAD pattern died. There was no relation between pattern and injury severity, geographic location, and state legality of recreational use of THC.

INTERPRETATION

EVALI typically causes an OP pattern but exists on a spectrum of acute lung injury. Vaping habits do not correlate with CT patterns except for negative correlation between vaping > 6 months and DAD pattern. PBV sparing, not previously described in acute lung injury, is a common finding.

Differential diagnoses of acute ground-glass opacity in chest computed tomography: pictorial essay

Ground-glass opacity is a very frequent and unspecified finding in chest computed tomography. Therefore, it admits a wide range of differential diagnoses in the acute context, from viral pneumonias such as influenza virus, coronavirus disease 2019 and cytomegalovirus and even non-infectious lesions, such as vaping, pulmonary infarction, alveolar hemorrhage and pulmonary edema. For this diagnostic differentiation, ground glass must be correlated with other findings in imaging tests, with laboratory tests and with the patients' clinical condition. In the context of a pandemic, it is extremely important to remember the other pathologies with similar findings to coronavirus disease 2019 in the imaging exams.

Vape-Associated Pulmonary Injury (VAPI) Presenting With a "Miliary" Pattern on Imaging

Electronic (E)-cigarette use or vaping is associated with pulmonary injury. Users can present with wide-ranging symptoms, varying degrees of pulmonary injury, and respiratory distress. Lung injury secondary to vaping is associated with a variety of patterns on pulmonary imaging. Typical radiographic findings are consistent with bilateral, basilar ground-glass opacities and or consolidation with septal thickening. We present a case of vape-associated pulmonary injury (VAPI) in a previously healthy adult who was found to have atypical radiographic findings. A 34-year-old male presented with a chief complaint of a two-week history of malaise, nausea, cough, and worsening shortness of breath. A chest CT scan without contrast revealed diffuse nodules in a miliary pattern. The patient reported a six-month history of tetrahydrocannabinol (THC) vape use. Bronchoscopy with cytologic analysis confirmed findings consistent with the VAPI. To our knowledge, this is the first report of a "miliary" pattern of infiltrates and nodules in a patient with VAPI. This pattern on CT imaging led to increased suspicion for other possible etiologies, including tuberculosis. Thus, moving forward, we believe that VAPI needs to be considered in the differential diagnosis if a patient presents with radiographic findings consistent with a miliary or diffuse micronodular pattern.

E-Cigarette or Vaping Product Use-Associated Lung Injury: A Review for Pathologists

CONTEXT.—

Vaping is the inhalation of heated aerosol from a small battery-powered device as a method to deliver nicotine or other substances. A recent outbreak of severe respiratory illness primarily in the United States has put a spotlight on vaping and its potential risks.

OBJECTIVE.—

To familiarize pathologists with vaping, the cytologic and histopathologic features of vaping-associated acute lung injury, and the role of pathology in this diagnosis.

DATA SOURCES.—

A targeted literature review was performed.

CONCLUSIONS.—

Most cases of vaping-associated lung injury have been linked to vaping products containing tetrahydrocannabinol or other cannabinoids. Lung biopsies show a spectrum of nonspecific acute lung injury patterns (organizing pneumonia, diffuse alveolar damage, acute fibrinous, and organizing pneumonia, or combinations of the above), accompanied by prominent, foamy macrophage accumulation. Injury is usually accentuated around small airways. Lipid-laden macrophages can be identified in bronchioloalveolar lavage fluid in most patients and these can be highlighted using lipid stains, such as oil red O, but the clinical utility of this finding remains unclear, as lipid-laden macrophages can be seen in a wide variety of processes and should not be relied upon to make the diagnosis. Classic histologic features of exogenous lipoid pneumonia have not been identified in tissue samples. Lightly pigmented macrophages, similar to those seen with traditional cigarette smoking, are present in some cases but are usually a minor feature. To date, no specific pathologic features for vaping-related injury have been identified, and it remains a diagnosis of exclusion that requires clinicopathologic correlation.

The Significance of Subpleural Sparing in CT Chest: A State-of-the-Art Review

The subpleural sparing pattern is a common finding on computed tomography (CT) of the lungs. It comprises of pulmonary opacities sparing the lung peripheries, typically 1cm and less from the pleural surface. This finding has a variety of causes, including idiopathic, inflammatory, infectious, inhalational, cardiac, traumatic, and bleeding disorders. Specific disorders that can cause subpleural sparing patterns include nonspecific interstitial pneumonia (NSIP), organizing pneumonia (OP), pulmonary alveolar proteinosis (PAP), diffuse alveolar hemorrhage (DAH), vaping-associated lung injury (VALI), cracked lung, pulmonary edema, pneumocystis jirovecii pneumonia (PJP), pulmonary contusion, and more recently, Coronavirus disease 2019 (COVID-19) pneumonia. Knowledge of the many etiologies of this pattern can be useful in preventing diagnostic errors. In addition, although the etiology of subpleural sparing pattern is frequently indistinguishable during an initial radiologic evaluation, the differences in location of opacities in the lungs, as well as the presence of additional radiologic findings, patient history, and clinical presentation, can often be useful to suggest the appropriate diagnosis. We did a comprehensive search on Pubmed and Google Scholar database using keywords of "subpleural sparing," "peripheral sparing," "sparing of peripheries," "CT chest," "chest imaging," and "pulmonary disease." This review aims to describe the primary differential diagnosis of subpleural sparing pattern seen on chest imaging with a strong emphasis on clinical and radiographic findings. We also discuss the pathogenesis and essential clues that are crucial to narrow the differential diagnosis.

Childhood interstitial lung disease: A case-based review of the imaging findings

Childhood interstitial lung disease (chILD) consists of a large, heterogeneous group of individually rare disorders. chILD demonstrates major differences in disease etiology, natural history, and management when compared with the adult group. It occurs primarily secondary to an underlying developmental or genetic abnormality affecting the growth and maturity of the pediatric lung. They present with different clinical, radiologic, and pathologic features. In this pictorial review article, we will divide chILD into those more prevalent in infancy and those not specific to infancy. We will use a case based approach to discuss relevant imaging findings including modalities such as radiograph and computed tomography in a wide variety of pathologies.

Vaping-related lung injury

The use of electronic nicotine delivery systems has increased in popularity dramatically over the past decade. Although lung diseases caused by vaping have been reported since the modern invention of the electronic cigarette, in the summer of 2019, patients began to present to health care centers at epidemic levels with an acute respiratory illness relating to vaping, which the Center for Disease Control termed E-cigarette or vaping product use-associated lung injury (EVALI). This review discusses electronic nicotine delivery systems as well as the etiology, clinical presentation, imaging findings, pathologic features, treatment, and long-term consequences of EVALI. We conclude with the practical impact EVALI has had on the practice of pathology.

The Role of Imaging in the Management of Suspected or Known COVID-19 Pneumonia. A Multidisciplinary Perspective

Coronavirus disease (COVID-19) is an illness caused by a novel coronavirus that has rapidly escalated into a global pandemic leading to an urgent medical effort to better characterize this disease biologically, clinically, and by imaging. In this review, we present the current approach to imaging of COVID-19 pneumonia. We focus on the appropriate use of thoracic imaging modalities to guide clinical management. We also describe radiologic findings that are considered typical, atypical, and generally not compatible with COVID-19. Furthermore, we review imaging examples of COVID-19 imaging mimics, such as organizing pneumonia, eosinophilic pneumonia, and other viral infections.

Clinical, Bronchoscopic, and Imaging Findings of e-Cigarette, or Vaping, Product Use-Associated Lung Injury Among Patients Treated at an Academic Medical Center

IMPORTANCE

e-Cigarette, or vaping, product use-associated lung injury (EVALI) has caused more than 2800 illnesses and 68 deaths in the United States. Better characterization of this novel illness is needed to inform diagnosis and management.

OBJECTIVE

To describe the clinical features, bronchoscopic findings, imaging patterns, and outcomes of EVALI.

DESIGN, SETTING, AND PARTICIPANTS

This case series of 31 adult patients diagnosed with EVALI between June 24 and December 10, 2019, took place at an academic medical center in Salt Lake City, Utah.

EXPOSURES

e-Cigarette use, also known as vaping.

MAIN OUTCOMES AND MEASURES

Symptoms, laboratory findings, bronchoscopic results, imaging patterns, and clinical outcomes.

RESULTS

Data from 31 patients (median [interquartile range] age, 24 [21-31] years) were included in the study. Patients were primarily men (24 [77%]) and White individuals (27 [87%]) who used e-cigarette products containing tetrahydrocannabinol (THC) (29 [94%]). Patients presented with respiratory (30 [97%]), constitutional (28 [90%]), and gastrointestinal (28 [90%]) symptoms. Serum inflammatory markers were elevated in all patients. Bronchoscopy was performed in 23 of 28 inpatients (82%) and bronchoalveolar lavage (BAL) revealed the presence of lipid-laden macrophages (LLMs) in 22 of 24 cases (91%). BAL samples tested positive for Pneumocystis jirovecii (3 patients [13%]), rhinovirus (2 patients [8%]), human metapneumovirus and Aspergillus (1 patient each [4%]); all except human metapneumovirus were determined to be false-positives or clinically inconsequential. The exclusive or dominant computed tomography (CT) pattern was organizing pneumonia in 23 of 26 cases (89%). Patients received antibiotics (26 [84%]) and corticosteroids (24 [77%]), and all survived; 20 patients (65%) seen in follow-up showed marked improvement, but residual symptoms (13 [65%]), radiographic opacities (8 [40%]), and abnormal pulmonary function tests (8 of 18 [44%]) were common.

CONCLUSIONS AND RELEVANCE

In this case series, patients with EVALI characteristically presented with a flu-like illness with elevated inflammatory markers, LLMs on BAL samples, and an organizing pneumonia pattern on CT imaging. Bronchoscopic testing for infection had a high incidence of false-positive results. Patients had substantial residual abnormal results at early follow-up. These data suggest a limited role for bronchoscopy in typical presentations of EVALI without risk factors for alternative diagnoses and the need for careful longitudinal follow-up.

Guidance on the Clinical Management of Electronic Cigarette or Vaping-Associated Lung Injury

In the summer of 2019, there was a rise in clusters of adolescents and young adults in the United States reporting to emergency departments with acute respiratory distress related to use of e-cigarette (electronic cigarette) or vaping. The number of patients with e-cigarette or vaping-associated lung injury continued to rise through the summer before peaking in September 2019. Through the efforts of state and federal public health agencies, officials were able to define the condition, identify the relationship of the respiratory injury to tetrahydrocannabinol-containing products, and stem the rise in new cases. In this report, we present a comprehensive review of the clinical characteristics and features of patients with e-cigarette or vaping-associated lung injury and guidelines for patient care and management to inform and navigate clinicians who may encounter these patients in their clinical practice.

E-cigarette or vaping product use-associated lung injury (EVALI) features and recognition in the emergency department

Since August 2019, the pulmonary disease termed e-cigarette or vaping product-use associated lung injury (EVALI), has resulted in 2758 hospitalizations and 64 deaths in the United States. EVALI is considered in patients who have vaped or dabbed within 90 days of symptom onset, and have abnormal lung imaging in the absence of any pulmonary infection. The majority of EVALI patients are otherwise healthy adolescents and young adults. The leading etiology of EVALI is contamination of delta-9-tetrahydrocannabinoid (THC) e-liquids with vitamin E acetate. Although the exact pathophysiology of vitamin E acetate-induced lung injury is unknown, vitamin E acetate may lead to pulmonary lipid accumulation and/or interfere with surfactant functioning. EVALI symptoms are vague but consist of a constellation of constitutional, pulmonary, and gastrointestinal symptoms. Patients often present multiple times to healthcare facilities as their clinical condition worsens with a considerable mortality risk. The diagnosis of EVALI hinges on obtaining history leading to the recognition of vaping/dabbing. Physicians need to be persistent, but nonjudgmental, in obtaining vaping histories, especially in THC-prohibited states. Radiographical findings of nonspecific bilateral ground-glass infiltrates are best detected on computed tomography. Management for EVALI requires a multidisciplinary approach focused on supportive respiratory care and ruling-out infectious causes. Corticosteroids may be of benefit. Most patients who are hypoxic, have comorbidities, or lack appropriate follow-up within 24-48 hours should be admitted for monitoring. Patients may benefit from substance abuse counseling and should be instructed to avoid vaping. As the outbreak continues, cases should be reported to local health departments and poison control centers.

Clinical and radiological characteristics of e-cigarette or vaping product use associated lung injury

PURPOSE

E-cigarette or vaping product use associated lung injury (EVALI) has received national attention as an epidemic resulting in cases of significant morbidity and mortality. We aim to present the clinical and imaging findings in adolescents with pulmonary symptoms from suspected EVALI.

METHODS

Chest radiographs and CTs of adolescents (< 19 years) with acute pulmonary symptoms and history of vaping were reviewed by two radiologists in consensus. Clinical presentation and laboratory data were derived from the electronic medical records including pulmonary function tests (PFTs).

RESULTS

Eleven patients were identified (9 male, mean 16.6 years). The most common presentation was progressive, subacute respiratory distress with abdominal pain. All but one of the patients tested positive for tetrahydrocannabinol. Chest radiograph features were notable for interstitial pattern of opacities (91%) and basilar abnormalities (82%). CT features were notable for ground-glass opacities (89%), interstitial opacities (78%), and subpleural sparing (67%). Eight patients underwent PFTs. Six had diffusing capacity measurement, which demonstrated impaired diffusion in 3 (50%). All patients received supportive treatment with supplemental oxygen and corticosteroids.

CONCLUSION

Adolescents with suspected EVALI commonly present with subacute respiratory distress with abdominal pain. Imaging findings include ground-glass opacities, subpleural sparing, and basilar opacities, most consistent with organizing pneumonia or hypersensitivity pneumonitis. Recognition of the common imaging findings may have significant patient management implications, especially if the diagnosis is not suspected clinically. The lung function effects of vaping are consistent with mildly reduced airflow, which improves on follow-up testing, and reduced diffusion capacity, which, concerningly, does not improve.

Radiologic and Pathologic Correlation in EVALI

OBJECTIVE. The purpose of this article is to characterize the appearance on CT of e-cigarette or vaping product use-associated lung injury (EVALI) in a cohort with histopathologic evidence of this disorder. MATERIALS AND METHODS. Twenty-four patients with EVALI were identified. Chest CT examinations were reviewed by two radiologists for various chest CT findings. For comparison with pathologic findings, CT assessments were distilled into previously described patterns of EVALI seen on CT: acute lung injury (ALI), chronic eosinophilic pneumonia (CEP) or organizing pneumonia (OP), acute eosinophilic pneumonia (AEP), alveolar hemorrhage, hypersensitivity pneumonitis (HP), lipoid pneumonia, and mixed or unclassifiable patterns. RESULTS. Sixteen of 24 (67%) patients were men; the mean age was 34.5 years (range, 17-67 years). The most common CT finding was ground-glass opacities, which was present in 23 of 24 (96%) patients and the dominant finding in 18 of 24 (75%) patients. Consolidation was the next most common finding in 42% of patients. Interlobular septal thickening was present in 29%. Lobular low attenuation was conspicuous in six patients. Distribution was multifocal in 54% of patients, peripheral in 17%, and centrally predominant in 8%. Subpleural sparing was seen in 45%. The predominant CT pattern was ALI (42%), concordant with histopathologic findings in 75%; the next most predominant pattern was ground-glass opacity centrilobular nodules resembling HP (33%). A CT pattern of CEP or OP was seen in 13% of patients, all showing ALI on lung biopsy. No patient showed macroscopic lung parenchymal fat. Two patients with CT ALI patterns showed OP on histopathologic examination. Of the eight patients with ground-glass opacity centrilobular nodules resembling HP at CT, none showed HP at histopathologic examination. CONCLUSION. EVALI manifests at CT as ALI with multifocal ground-glass opacity, often with organizing consolidation, and a small centrilobular nodular pattern resembling HP.

Pulmonary Injury Resulting from Vaping or e-Cigarette Use: Imaging Appearances at Presentation and Follow-up

Electronic cigarette or vaping product use-associated lung injury most frequently presents with an acute lung injury pattern at CT, manifesting as multifocal ground-glass opacity and/or consolidation, typically multifocal and multilobar, possibly with subpleural sparing. Areas of organization, manifesting as contracting consolidation, mild architectural distortion, intralobular lines, lobular distortion, and traction bronchiectasis may occur as the illness evolves. A CT appearance resembling hypersensitivity pneumonitis, reflecting the exquisitely bronchiolocentric micronodular lesions of organizing pneumonia and acute lung injury seen at histopathologic findings in these patients, may be encountered. Less common CT appearances include organizing pneumonia or acute eosinophilic pneumonia patterns, the latter consisting of multifocal opacity and smooth interlobular septal thickening, possibly with small effusions, but without clinical evidence of volume overload. Patients may present with pneumothorax or pneumomediastinum, or these conditions may develop during their illness course. Most patients improve clinically and at imaging on follow-up, particularly following exposure cessation and corticosteroid therapy, but the time course to improvement is variable and most likely related to the severity of the lung injury. Radiologists should be familiar with the imaging manifestations of vaping-associated pulmonary injury, and the possibility of this condition should be considered when the imaging findings reviewed in this article are encountered. © RSNA, 2020.

E-cigarette or vaping product use-associated lung injury in the pediatric population: imaging features at presentation and short-term follow-up

BACKGROUND

Cases of e-cigarette or vaping product use-associated lung injury (EVALI) have rapidly reached epidemic proportions, yet there remain limited reports within the literature on the associated imaging findings.

OBJECTIVE

We describe the most common imaging findings observed on chest computed tomography (CT) and chest radiograph (CXR) at presentation and at short-term follow-up at our major pediatric hospital.

MATERIALS AND METHODS

A retrospective review of the electronic medical records was performed on all patients with suspected EVALI who were treated at a major pediatric hospital and 11 patients were included for analysis. Two board-certified pediatric radiologists then categorized the CXRs as either normal or abnormal, and further performed a systematic review of the chest CTs for imaging findings in the lungs, pleura and mediastinum. Interrater discordance was reconciled by consensus review.

RESULTS

The 11 patients (9 males:2 females) ranged in age from 14 to 18 years. Gastrointestinal and constitutional symptoms were present in all patients, whereas shortness of breath and cough were reported in 5/11 and 6/11 patients, respectively. The CXR was abnormal in 10/11 patients, whereas all chest CTs were abnormal. The most common CT findings included consolidation, ground-glass opacities, interlobular septal thickening, lymphadenopathy and crazy-paving pattern. Almost all patients demonstrated subpleural sparing, and less than half also demonstrated peribronchovascular sparing. There was complete or near-complete resolution of imaging abnormalities in 5/6 patients with a median follow-up duration of 114 days.

CONCLUSION

Pulmonary opacities with subpleural and peribronchovascular sparing was a commonly observed pattern of EVALI in the pediatric population at this institution. A CXR may not be sufficiently sensitive in diagnosing EVALI, and radiologists and clinicians should exercise caution when excluding EVALI based on the lack of a pulmonary opacity. Caution should also be exercised when excluding EVALI solely based on the lack of respiratory symptoms. Despite extensive pulmonary involvement at presentation, findings may resolve on short-term follow-up imaging.

A review of toxic effects of electronic cigarettes/vaping in adolescents and young adults

In this review, we examine the known and suspected toxicity of electronic cigarettes (e-cigarettes) in adolescents and young adults, to improve awareness of risks and identification of complications of their use. The use of e-cigarettes, or "vaping," is exploding among the pediatric population. E-cigarettes heat a solution containing a psychoactive compound, most commonly nicotine or tetrahydrocannabinol (THC), along with flavorings and other additives to a vapor, which users inhale. Since their introduction in the early 2000s, e-cigarette use is now prolific among youth, per the Monitoring the Future survey, with over 40% of high school seniors reporting use within the past year. Adolescents are vulnerable to the risks of e-cigarettes, as they are targeted as new consumers with advertisements and flavoring compounds, and are not utilizing them as a means to smoking cessation. The pulmonary risks of vaping are rapidly emerging, with the most immediately alarming being the condition electronic-cigarette/vaping associated lung injury (EVALI). Additionally, there have been more recent studies showing extrapulmonary effects including cardiovascular, immunologic and neuro-developmental effects. Many of these effects are likely dose-dependent. Public health efforts are urgently needed to decrease or eliminate new e-cigarette initiation, and support should be established to assist current e-cigarette users with cessation. We strongly advocate for the elimination of e-cigarette flavorings and advertising directed at adolescents, and call for physicians to be cognizant of this expanding epidemic.

A Case-Based Review of Vaping-Induced Injury-Pulmonary Toxicity and Beyond

The last 10 years has seen a steady rise in the use of electronic cigarettes ("e-cigarettes" or ECIGs) or "vape pens." Though initially developed to assist with smoking cessation, use among adolescents has been particularly high. A concomitant rise in ECIG-related injuries disproportionately affecting young patients has been recognized. This unique case series highlights both pulmonary and extra-pulmonary ECIG-induced injuries including vape tip ingestion, maxillofacial fractures after vape pen explosion, myocarditis, and several different manifestations of vaping-associated lung injury. Becoming familiar with expected imaging findings in the wide array of ECIG-induced complications will help radiologists recognize these findings, recommend further imaging as needed, facilitate early diagnosis by help referring clinicians elicit the relevant history from patients, and expedite appropriate treatment.

The importance of anti-vaping vigilance-EVALI in seven adolescent pediatric patients in Northeast Ohio

As of 18 February 2020, the e-cigarette or vaping product use-associated lung injury (EVALI) epidemic has claimed the lives of 68 patients in the USA with the total number of reported cases standing at 2807 to date. We present the clinical and radiologic findings, course of illness, and treatment of EVALI in seven adolescent patients in Northeast Ohio. Five of our patients required supplemental oxygen with four requiring intensive care unit care for respiratory support during admission. Three patients were treated with systemic steroids while inpatient. Bilateral opacities were seen on radiographic imaging of all seven of our patients. All patients were discharged alive on room air. However, impaired diffusing capacity of the lungs for carbon monoxide (DLCO) with nonobstructive spirometry was seen in patients that were tested postdischarge. This suggests that although recovery from the acute illness process of EVALI is achieved, there may be long-term impact on lung function in these patients. We recommend close follow-up with a pediatric pulmonologist where spirometry and DLCO can be performed.

Vaping associated lung injury: A potentially life-threatening epidemic in US youth

BACKGROUND

The Center for Disease Control (CDC) has identified a national outbreak in the United States of over 2600 cases of e-cigarette or vaping product use-associated lung injury (EVALI), including 60 deaths as of January 2020. We describe our experience in six adolescents.

MATERIAL AND METHODS

We identified all pediatric patients diagnosed with EVALI by CDC guidelines over a 6-month period at our health system. Clinical presentation, hospital course, and imaging were reviewed.

RESULTS

Six patients were identified (three males, three females; median age 18.5 years). Presenting symptoms varied, including constitutional, gastrointestinal, neurologic, and respiratory complaints with pulmonary symptomatology becoming the dominant feature of the illness. Three patients required intensive care unit-level care, one of whom expired 36 days after presentation. Three had bronchoalveolar lavage, two with evidence of lipid-laden macrophages. Four had pulmonary function testing with various results. Admission chest radiographs in all revealed bibasilar interstitial infiltrate which rapidly progressed. Five patients had computed tomography chest imaging demonstrating: confluent pulmonary infiltrates with subpleural sparing (n = 2), generalized ground-glass opacities (n = 1), patchy ground-glass opacities (n = 1) and a reticulonodular pattern (n = 1). Brain magnetic resonance imaging (MRI) obtained in two patients was normal in one and showed a focal signal abnormality in the corpus callosum in one.

CONCLUSION

We describe the clinical course and radiologic findings of EVALI in our adolescent patients and present a new finding in the brain not yet described in the literature. Given the diversity of presenting symptoms, a high level of suspicion for EVALI is necessary for patients reporting vaping product use regardless of the presence of pulmonary complaints. Brain MRI should be strongly considered in patients with neurologic symptoms.

Review of Health Consequences of Electronic Cigarettes and the Outbreak of Electronic Cigarette, or Vaping, Product Use-Associated Lung Injury

Electronic cigarettes (e-cigarettes) are battery-operated devices to insufflate nicotine or other psychoactive e-liquid aerosols. Despite initial claims of e-cigarettes as a nicotine-cessation device, aggressive marketing of e-cigarettes has led to an explosion in adolescents' and young adults' use over the last few years. Coupled with a lack of adequate investigation and regulation of e-cigarettes, the USA is facing an outbreak of e-cigarette, or vaping, product use-associated lung injury (EVALI) starting in mid-2019. While little long-term health hazard data are available, the components and constituents of e-cigarettes may adversely impact health. Propylene glycol and glycerin are humectants (water-retaining excipients) that generate pulmonary irritants and carcinogenic carbonyl compounds (e.g., formaldehyde, acetaldehyde, and acrolein) when heated in e-cigarettes. Metals contained in heating coils and cartridge casings may leach metals such as aluminum, chromium, iron, lead, manganese, nickel, and tin. Flavoring agents are considered safe for ingestion but lack safety data for inhalational exposures. Diacetyl, a common buttery flavoring agent, has known pulmonary toxicity with inhalational exposures leading to bronchiolitis obliterans. In 2019, clusters of lung injury associated with e-cigarette use were identified in Wisconsin and Illinois. Patients with EVALI present with a constellation of respiratory, gastrointestinal, and constitutional symptoms. Radiographically, patients have bilateral ground glass opacifications. As of February 18, 2020, the Centers for Disease Control has identified 2807 hospitalized patients diagnosed with either "confirmed" or "probable" EVALI in the US. Currently, vitamin E acetate (VEA) used as a diluent in tetrahydrocannabinol vape cartridges is implicated in EVALI. VEA cuts tetrahydrocannabinol oil without changing the appearance or viscosity. When inhaled, pulmonary tissue lacks the mechanism to metabolize and absorb VEA, which may lead to its accumulation. While most EVALI patients were hospitalized, treatment remains largely supportive, and use of corticosteroids has been associated with clinical improvement. The outbreak of EVALI highlights the need for regulation of e-cigarette devices and e-liquids. Clinicians need to be aware of the health hazards of e-cigarettes and be vigilant in asking about vaping.

Review of Cases of E-Cigarette or Vaping Product Use-Associated Lung Injury (EVALI) and Brief Review of the Literature

Since the appearance of the E-Cigarette in the early 2000s, its industry, popularity, and prevalence have risen dramatically. In the past, E-Cigarette use with the vaping of nicotine or cannabis products had been associated with a few reported cases of lung injury. However, in 2019, thousands of cases of E-Cigarette or vaping product use-associated lung injury (EVALI) were reported in the United States. Evidence linked this outbreak with vaping of tetrahydrocannabinol (THC). We report two confirmed cases of EVALI and their associated clinical, radiologic, and pathologic features. This report supports the growing body of information regarding EVALI. It also discusses various substances, particularly vitamin E acetate, which has been suggested as a causative agent.

E-Cigarette or Vaping Product-Associated Lung Injury: A Review

Since its introduction in the US market in 2007, the use of electronic nicotine delivery systems, colloquially referred to as e-cigarettes or "vaping" products, has increased substantially, particularly among high school children and young men. With the legalization of marijuana within multiple states in the United States and thus, coincident change in the public perception of its risk, the availability of multiple tetrahydrocannabinol (the psychoactive agent in marijuana)- and cannabidiol (a nonpsychogenic agent in marijuana)- containing vaping products has also increased tremendously. Since March 2019, there has been an ongoing epidemic of acute lung injury secondary to the use of e-cigarettes, with over 2600 cases and 60 deaths reported all over the United States; the term e-cigarette- or vaping product-associated lung injury is used. E-cigarette- or vaping product-associated lung injury is defined by the 1) presence of pulmonary infiltrates in imaging; 2) use of electronic nicotine delivery systems within the previous 90 days; and 3) absence of other possible causes such as infection, cardiac, neoplastic, or rheumatologic causes. A significant proportion of patients hospitalized with e-cigarette- or vaping product-associated lung injury have required admission in the intensive care unit, with mechanical ventilation needed in up to one-third of patients. Corticosteroids, supportive care, and further avoidance of vaping products remain the cornerstone of treatment. Although generally associated with an excellent prognosis, older patients and patients with underlying cardiac and pulmonary conditions are at risk for higher mortality and morbidity. This review article aims to describe e-cigarette- or vaping product-associated lung injury, its pathogenesis, clinical and radiological manifestations, and management.

Cytotoxic lesion of the splenium of the corpus callosum in a patient with EVALI

Since first recognized in July 2019, numerous cases of a lung illness associated with electronic-cigarette use or vaping particularly tetrahydrocannabinol in adolescents and adults have been reported. As of January 2020, the Center for Disease Control has reported over 2500 cases of electronic-cigarette or vaping product use-associated lung injury (EVALI), including 60 deaths. Affected patients most commonly present with respiratory or gastrointestinal complaints although neurological symptoms including headache, confusion and lethargy have been reported. We present a new as yet unpublished finding in the brain of a previously healthy teenage boy with EVALI. Brain imaging may be warranted in this patient population.