Not your typical pneumonia: a case of exogenous lipoid pneumonia

Biophysical impact of lubricating base oil aerosols on natural pulmonary surfactant film

Lubricating base oils have been extensively employed for producing various industrial and consumer products. Therefore, their environmental and health impacts should be carefully evaluated. Although there have been many reports on pulmonary cytotoxicity and inflammatory responses of inhaled lubricating base oils, their potential influences on pulmonary surfactant (PS) films that play an essential role in maintaining respiratory mechanics and pulmonary immunity remains largely unknown. Here a systematic study on the interactions between an animal-derived natural PS and aerosols of water and representative mineral and vegetable base oils is performed using a novel biophysical assessing technique called constrained drop surfactometry capable of providing in vitro simulations of normal tidal breathing and physiologically relevant temperature and humidity in the lung. It was found that the mineral oil aerosols can impose strong inhibitions to the biophysical property of PS film, while the airborne vegetable oils and water show negligible adverse effects within the studied concentration range. The inhibitory effect is originated from the strong hydrophobicity of mineral oil, which makes it able to disrupt the interfacial molecular ordering of both phospholipid and protein compositions and consequently suppress the formation of condensed phase and multilayer scaffolds in a PS film. ENVIRONMENTAL IMPLICATION: Understanding the biophysical influence of airborne lubricating base oils on pulmonary surfactant (PS) films can provide new insights into the environmental impacts and health concerns of various industrial lubricant products. Here a comparative study on interactions between an animal-derived natural PS film and the aerosols of water and representative mineral and vegetable base oils under the true physiological conditions was conducted in situ using constrained drop surfactometry. We show that the most frequently used mineral base oil can cause strong inhibitions to the PS film by disrupting the molecular ordering of saturated phospholipids and surfactant-associated proteins at the interface.

A rare case of lipoid pneumonia mimicking lung malignancy on radiological imaging: A case report

Lipoid pneumonia is a rare benign lung disease pathologically characterized by the presence of lipids in the alveoli. It may mimic lung malignancy on radiological imaging. In this case report we present a case of lipoid pneumonia that radiologically manifested as a lung mass and summarize the typical investigation findings and the management of the disease from the literature review to serve as a reminder of and refresh our knowledge of this rare disease entity.

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.

Pulmonary Toxicity and Inflammatory Response of E-Cigarette Vape Cartridges Containing Medium-Chain Triglycerides Oil and Vitamin E Acetate: Implications in the Pathogenesis of EVALI

Recently, there has been an outbreak of a condition named e-cigarette or vaping products-associated lung injury (EVALI). The primary components of vaping products include tetrahydrocannabinol (THC), vitamin E acetate (VEA) and medium-chain triglycerides (MCT), may be responsible for acute lung toxicity. Currently, little information is available on the physiological and biological effects of exposure to these products. We hypothesized that these CBD/counterfeit vape cartridges and their constituents (VEA and MCT) induce pulmonary toxicity, mediated by oxidative damage and inflammatory responses, leading to acute lung injury. We studied the potential mechanisms of CBD/counterfeit vape cartridge aerosol induced inflammatory response by evaluating the generation of reactive oxygen species by MCT, VEA, and cartridges and their effects on the inflammatory state of pulmonary epithelium and immune cells both in vitro and in vivo. Cells exposed to these aerosols generated reactive oxygen species, caused cytotoxicity, induced epithelial barrier dysfunction, and elicited an inflammatory response. Using a murine model, the parameters of acute toxicity to aerosol inhalation were assessed. Infiltration of neutrophils and lymphocytes was accompanied by significant increases in IL-6, eotaxin, and G-CSF in the bronchoalveolar lavage fluid (BALF). In mouse BALF, eicosanoid inflammatory mediators, leukotrienes, were significantly increased. Plasma from e-cig users also showed increased levels of hydroxyeicosatetraenoic acid (HETEs) and various eicosanoids. Exposure to CBD/counterfeit vape cartridge aerosols showed the most significant effects and toxicity compared to MCT and VEA. In addition, we determined SARS-CoV-2 related proteins and found no impact associated with aerosol exposures from these tested cartridges. Overall, this study demonstrates acute exposure to specific CBD/counterfeit vape cartridges induces in vitro cytotoxicity, barrier dysfunction, and inflammation and in vivo mouse exposure induces acute inflammation with elevated proinflammatory markers in the pathogenesis of EVALI.

Pulmonary toxicity and inflammatory response of e-cigarettes containing medium-chain triglyceride oil and vitamin E acetate: Implications in the pathogenesis of EVALI but independent of SARS-COV-2 COVID-19 related proteins

Recently, there has been an outbreak associated with the use of e-cigarette or vaping products, associated lung injury (EVALI). The primary components of vaping products, vitamin E acetate (VEA) and medium-chain triglycerides (MCT) may be responsible for acute lung toxicity. Currently, little information is available on the physiological and biological effects of exposure to these products. We hypothesized that these e-cig cartridges and their constituents (VEA and MCT) induce pulmonary toxicity, mediated by oxidative damage and inflammatory responses, leading to acute lung injury. We studied the potential mechanisms of cartridge aerosol induced inflammatory response by evaluating the generation of reactive oxygen species by MCT, VEA, and cartridges, and their effects on the inflammatory state of pulmonary epithelium and immune cells both in vitro and in vivo. Cells exposed to these aerosols generated reactive oxygen species, caused cytotoxicity, induced epithelial barrier dysfunction, and elicited an inflammatory response. Using a murine model, the parameters of acute toxicity to aerosol inhalation were assessed. Infiltration of neutrophils and lymphocytes was accompanied by significant increases in IL-6, eotaxin, and G-CSF in the bronchoalveolar lavage fluid (BALF). In mouse plasma, eicosanoid inflammatory mediators, leukotrienes, were significantly increased. Plasma from e-cig users also showed increased levels of hydroxyeicosatetraenoic acid (HETEs) and various eicosanoids. Exposure to e-cig cartridge aerosols showed the most significant effects and toxicity compared to MCT and VEA. In addition, we determined at SARS-COV-2 related proteins and found no impact associated with aerosol exposures from these tested cartridges. Overall, this study demonstrates acute exposure to specific e-cig cartridges induces in vitro cytotoxicity, barrier dysfunction, and inflammation and in vivo mouse exposure induces acute inflammation with elevated pro-inflammatory markers in the pathogenesis of EVALI.

The Diagnosis of Exogenous Lipoid Pneumonia Caused by the Silent Aspiration of Vegetable Oil Using a Lipidomic Analysis

We herein report a case of refractory exogenous lipoid pneumonia that was successfully attributed to vegetable oil through a lipidomic analysis of bronchoalveolar lavage fluid (BALF). As a 25-year-old woman diagnosed with lipoid pneumonia experienced repeated exacerbations and improvement, we performed a BALF lipidomic analysis. The major lipid components were oleic acid, linoleic acid, and α-linolenic acid, which are constituents of vegetable oil. She stopped consuming any vegetable oil and has since experienced no instances of lipoid pneumonia relapse. A lipidomic analysis appears to be useful for identifying causative lipids, since patients with lipoid pneumonia are sometimes unaware of aspiration episodes.

A rare case of lipoid pneumonia attributed to amiodarone

We report a case of endogenous lipoid pneumonia secondary to long-term use of amiodarone (> 30 years) for atrial fibrillation in a 76-year-old Caucasian woman, presenting with cough and dyspnea. Endogenous Lipoid pneumonia is a rare underdiagnosed condition more prevalent in adults. It is usually asymptomatic and a diagnosis is generally made in patients who have become clinically unstable or when an abnormal lung shadow is found on a chest X-ray. In the case here described it was diagnosed by fiberoptic bronchoscopy with bronchoalveolar lavage (BALF) where fat-laden macrophages (oil red O stain) were identified. Since a history of use of oil-based products had been ruled out, amiodarone was deemed to be the most likely cause of lipoid pneumonia. The patient was managed with the replacement of amiodarone with digoxin and treated with oral prednisolone. The patient has remained clinically stable with radiological improvement during a follow-up of two years.

Adult exogenous lipoid pneumonia: A rare and underrecognized entity in cytology - A case series

Background:

Exogenous lipoid pneumonia (ELP) is a rare benign entity without specific clinical or imaging presentation. Although cytological studies – either bronchoalveolar lavage (BAL) or fine-needle aspiration (FNA) – may be pursued in patients with ELP, a definitive diagnosis is frequently rendered only on histology. The aim of this study is to highlight the cytological features of ELP.

Methods:

A search of cytopathology (CP) and surgical pathology (SP) diagnoses of ELP was conducted. The corresponding clinical and imaging features were obtained, and the morphology, particularly the presence and size of the intracytoplasmic vacuoles and background, was assessed.

Results:

Nine cases of ELP were identified, including eight with corresponding CP and SP. A neoplasm was suspected in three based on imaging, but ELP was not in the differential clinically or radiographically in any. Among the cases, six patients had BALs and three FNAs. All of the samples showed multiple large vacuoles within macrophages with at least some equal to or larger than the size of the cell nucleus. Similar vacuoles were noted extracellularly on smears.

Conclusions:

ELP is typically described in case reports in the clinical or radiological literature. To the best of our knowledge, this represents the largest series of adult ELP in CP. When large vacuoles are present in macrophages in cytology specimens, at least a suspicion of ELP can be suggested to initiate appropriate therapy, identify/remove the inciting agent, and preclude a more invasive procedure.

Pathogenesis of Diffuse Alveolar Hemorrhage in Murine Lupus

OBJECTIVE

Diffuse alveolar hemorrhage (DAH) in lupus patients confers >50% mortality, and the cause is unknown. We undertook this study to examine the pathogenesis of DAH in C57BL/6 mice with pristane-induced lupus, a model of human lupus-associated DAH.

METHODS

Clinical/pathologic and immunologic manifestations of DAH in pristane-induced lupus were compared with those of DAH in humans. Tissue distribution of pristane was examined by mass spectrometry. Cell types responsible for disease were determined by in vivo depletion using clodronate liposomes and antineutrophil monoclonal antibodies (anti-Ly-6G). The effect of complement depletion with cobra venom factor (CVF) was examined.

RESULTS

After intraperitoneal injection, pristane migrated to the lung, causing cell death, small vessel vasculitis, and alveolar hemorrhage similar to that seen in DAH in humans. B cell-deficient mice were resistant to induction of DAH, but susceptibility was restored by infusing IgM. C3^-/- and CD18^-/- mice were also resistant, and DAH was prevented in wild-type mice by CVF. Induction of DAH was independent of Toll-like receptors, inflammasomes, and inducible nitric oxide. Mortality was increased in interleukin-10 (IL-10)-deficient mice, and pristane treatment decreased IL-10 receptor expression in monocytes and STAT-3 phosphorylation in lung macrophages. In vivo neutrophil depletion was not protective, while treatment with clodronate liposomes prevented DAH, which suggests that macrophage activation is central to DAH pathogenesis.

CONCLUSION

The pathogenesis of DAH involves opsonization of dead cells by natural IgM and complement followed by complement receptor-mediated lung inflammation. The disease is macrophage dependent, and IL-10 is protective. Complement inhibition and/or macrophage-targeted therapies may reduce mortality in lupus-associated DAH.

A fatty cough

Lipoid pneumonia is a rare form of pneumonia caused by accumulation of exogenous or endogenous lipids in the pulmonary system. Symptoms can often range from being asymptomatic to presenting with chest pain, fevers and shortness of breath. High resolution CT and bronchoalveolar lavage (BAL) remain important in establishing the diagnosis. The treatment of lipoid pneumonia includes stopping the offending agents and providing supportive therapy. The use of anti-inflammatory agents has shown some benefit in severe cases.

Exogenous lipid pneumonia related to long-term use of Vicks VapoRub® by an adult patient: a case report

Background

Use of petroleum-based over the counter remedies such as Vicks VapoRub to alleviate symptoms of rhinitis is common and can be effective, but carries under-appreciated risks of adverse side effects. In this case report we highlight Exogenous Lipoid Pneumonia (ELP), an uncommon condition that results from accumulation of exogenous lipids in the alveoli, as an adverse side effect of long-term Vicks VapoRub use.

Case presentation

We present the case of an 85-year-old female patient with ELP apparently due to continuous application of Vicks VapoRub® to her nostrils to alleviate chronic rhinitis. She was diagnosed incidentally via chest radiograph and computed tomography (CT) scan done as follow up to finding elevated C-reactive Protein during a routine exam. The CT scan revealed a pulmonary consolidation in the lower lobe of the right lung with fat density combined with low density areas associated with focal ground-glass opacities. The patient was advised to discontinue use of petroleum-based products, and was prescribed intranasal corticosteroids for her rhinitis. Follow up 2 years later showed that the lipid consolidation had diminished in size by approximately 10 %.

Conclusion

Physicians must be aware that ELP can develop as a result of long-term application of petroleum-based oils and ointments to the nose and discourage such use of these products. Patients who have used petroleum-based products in this way should be screened for ELP. CT scan is the best imaging modality for establishing the diagnosis. The treatment of this condition is not well defined, but, as shown in this case, the size of the lipid mass can decrease after use of petroleum based substances is discontinued.

Electronic supplementary material

The online version of this article (doi:10.1186/s12901-016-0032-6) contains supplementary material, which is available to authorized users.

Plugs of the Air Passages: A Clinicopathologic Review

Although mucus is a normal product of the tracheobronchial tree, some diseases of the respiratory tract are characterized by unusually thick (inspissated) forms of mucus that accumulate within the airways. These are known as mucus plugs. The pathologic composition of these plugs is surprisingly diverse and, in many cases, correlates with distinctive clinical, radiologic, and bronchoscopic findings. The best-known conditions that involve mucus plugs are allergic bronchopulmonary aspergillosis, plastic bronchitis, and asthma. Other lung diseases occasionally associated with plugs within the airways include Aspergillus tracheobronchitis, hyper-IgE syndrome, exogenous lipoid pneumonia, pulmonary alveolar proteinosis, and chronic eosinophilic pneumonia. In this review, we describe and illustrate the bronchoscopic, pathologic, and imaging findings in respiratory disorders characterized by mucus plugs or plugs composed of other similar materials. Recognition of the characteristic appearance and differential diagnosis of mucus plugs will hopefully facilitate diagnosis and management of these diseases.

Mycobacterium fortuitum lipoid pneumonia in a dog

A 1-year old female spayed German Shepherd dog was evaluated for acute onset of dyspnea. Pyogranulomatous inflammation and green globoid structures were present on aspirates of the affected lung. Impression smears and histopathology confirmed pyogranulomatous pneumonia, with large amounts of lipid corresponding to the green structures noted cytologically, and identified poorly staining bacterial rods within lipid vacuoles. Special stains confirmed the presence of acid-fast bacterial rods, and polymerase chain reaction and DNA sequencing identified the organism as Mycobacterium fortuitum. M. fortuitum pneumonia is well described in humans and has previously been reported in 4 dogs and 1 cat. Lipid was a prominent cytologic and histologic feature, as is often described in humans and in the single feline case report. Additionally, this case highlights the variable cytologic appearance of lipid, as well as Mycobacterium spp, which are classically nonstaining with Wright-Giemsa.

Lipoid pneumonia: a challenging diagnosis

Lipoid pneumonia is a rare medical condition, and is usually classified into two groups, ie, exogenous or endogenous, depending on the source of lipids found in the lungs. Exogenous lipoid pneumonia may result from the aspiration of food and lipids. Although most cases are asymptomatic, common symptoms include cough, dyspnea, chest pain, pleural effusions, fever, and hemoptysis. Radiologically, lipoid pneumonia can manifest as consolidations, pulmonary nodules, or soft-tissue densities. These presentations involve a wide differential diagnosis, including lung cancer. Other rare causes of fatty pulmonary lesions include hamartomas, lipomas, and liposarcomas. The avoidance of further exposures and the use of corticosteroids, antibiotics, and lavage comprise the mainstays of treatment. The exclusion of mycobacterial infections is important during diagnosis, in view of their known association. Generally, acute presentations run a benign course, if promptly treated. Chronic cases are more persistent and difficult to treat. Although the radiologic and pathologic diagnosis is fairly reliable, more research is needed to clarify the optimal treatment and expected outcomes. We report on a 54-year-old man presenting with progressively worsening cough, hemoptysis, and dyspnea over a few weeks. The patient underwent multiple computed tomographies of the chest and bronchoscopies. All failed to diagnose lipoid pneumonia. The diagnosis was finally established using video-assisted thoracoscopic surgery. Most of the paraffinoma was resected during this surgery. He was treated with antibiotics and steroids, and discharged from the hospital in stable condition.

Evolução da pneumonia lipoide exógena em crianças: aspectos clínicos e radiológicos e o papel da lavagem broncoalveolar

OBJETIVO: Descrever os aspectos da evolução da pneumonia lipoide em crianças, com base em aspectos clínicos, radiológicos e de achados no lavado broncoalveolar, enfatizando a importância diagnóstica e terapêutica da lavagem broncoalveolar. MÉTODOS: Foram incluídas 28 crianças, com idade média de 20 meses (1-108 meses) e diagnóstico de pneumonia crônica refratária a antimicrobianos e/ou TB. A maioria apresentava um fator de risco para aspiração, e todas apresentavam história de ingestão de óleo mineral para o tratamento de constipação intestinal (23/28) ou de ascaridíase complicada (5/28). A avaliação clínica e tomográfica e análises do lavado broncoalveolar foram realizadas no início do tratamento e em até 24 meses. RESULTADOS: Os sintomas mais frequentes foram taquipneia e tosse. As principais alterações radiológicas foram consolidações (23/28), infiltrado peri-hilar (13/28) e hiperinsuflação (11/28). A TC de tórax mostrou consolidações com broncograma aéreo (24/28), diminuição de atenuação nas áreas de consolidação (16/28), opacidade em vidro fosco (3/28) e padrão em mosaico (1/28). O estudo do lavado broncoalveolar apresentava macrófagos espumosos corados por Sudan, confirmando o diagnóstico da pneumonia lipoide. Após tratamento com múltiplas lavagens broncoalveolares (média = 9,6), 20 crianças tornaram-se assintomáticas, havendo normalização tomográfica em 18. CONCLUSÕES: O diagnóstico de pneumonia lipoide deve ser considerado na pneumonia crônica ou TB refratárias ao tratamento, especialmente se houver história de ingestão de óleo mineral. A broncoscopia com múltiplas lavagens broncoalveolares mostrou-se eficiente para a depuração do óleo aspirado do parênquima pulmonar e a prevenção da fibrose, contribuindo para a redução da morbidade dessa doença, que ainda é pouco diagnosticada.

Clinic and radiological improvement of lipoid pneumonia with multiple bronchoalveolar lavages

OBJECTIVE

To assess the potential role of multiple bronchoalveolar lavages (BALs) in the treatment of children with lipoid pneumonia (LP).

MATERIALS AND METHODS

This prospective study included 10 children (7 female, 3 male) with LP secondary to mineral oil aspiration. The age ranged from 3 months to 7 years and 1-60 days history of mineral oil intake, with a 6 months clinic follow-up. High-resolution computer tomography (CT) was performed 1-7 days prior to treatment and 2-20 days after the last therapeutic BAL, and reviewed by two experienced chest radiologists. Oxygen saturation was measured with digital oximetry. Therapeutic BAL was performed weekly until BAL fluid was nearly transparent and the cell count returned to normal range values.

RESULTS

In all children, the initial CT scans showed multifocal bilateral consolidation involving mainly the dorsal and central regions. The areas of consolidation had foci of decreased attenuation in eight patients. Following a total of 4-10 therapeutic BALs, the CT scans returned to normal in 3 patients, improved considerably in 5, and showed only slight improvement in 2. Oxygen saturation increased from 88.8 +/- 3.4% at presentation to 96.2 +/- 0.8% after treatment (P < 0.0001). Multiple lavages reduced (P < 0.003) numbers of lipid-laden macrophages and restored BAL cellularity to normal range values.

CONCLUSION

Multiple therapeutic BAL of children with LP results in significant improvement of CT findings, oxygen saturation, restoration of BAL fluid cellularity and clinical recover without any evidence of respiratory distress at the end of treatment and 6 months after the last BAL.

Principles of encapsulating hydrophobic drugs in PLA/PLGA microparticles

Injectable biodegradable and biocompatible copolymers of lactic and glycolic acid (PLGA) are an important advanced delivery system for week-to-month controlled release of hydrophobic drugs (e.g., from biopharmaceutical classification system class IV), which often display poor oral bioavailability. The basic principles and considerations to develop such microparticle formulations is reviewed here based on a comprehensive study of papers and patents from the beginnings of hydrophobic drug encapsulation in polylactic acid and PLGA up through the very recent literature. Challenges with the diversity of drug properties, microencapsulation methods, and organic solvents are evaluated in light of the precedence of commercialized formulations and with a focus on decreasing the time to lab-scale encapsulation of water-insoluble drug candidates in the early stage of drug development. The influence of key formulation variables on final microparticle characteristics, and how best to avoid undesired microparticle properties, is analyzed mechanistically. Finally, concepts are developed to manage the common issues of maintaining sink conditions for in vitro drug release assays of hydrophobic compounds. Overall, against the backdrop of an increasing number of new, poorly orally available drug entities entering development, microparticle delivery systems may be a viable strategy to rescue an otherwise undeliverable substance.