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Vaping-induced diffuse alveolar hemorrhage

There are growing reports of adverse health effects from e-cigarette use or vaping. The U.S. Centers for Disease Control and Prevention has reported 2409 cases and 52 deaths associated with e-cigarette use as of December 10, 2019. Vaping has been associated with acute eosinophilic pneumonia, organizing pneumonia, lipoid pneumonia, diffuse alveolar damage, acute respiratory distress syndrome, hypersensitivity pneumonia, and giant cell interstitial pneumonitis. Here we present a case of vaping-associated diffuse alveolar hemorrhage.


Introduction
The use of electronic cigarettes (e-cigarettes) and related devices to vaporize nicotine and flavored solutions has increased in recent years. There are growing reports of adverse health effects from e-cigarette use or vaping. Vaping has been associated with acute eosinophilic pneumonia, organizing pneumonia, lipoid pneumonia, diffuse alveolar damage, acute respiratory distress syndrome, hypersensitivity pneumonia, and giant cell interstitial pneumonitis [1][2][3][4]. The U.S. Centers for Disease Control and Prevention (CDC) has reported 2409 cases and 52 deaths associated with e-cigarette use as of December 10, 2019 [5]. Here we present a case of vaping-associated diffuse alveolar hemorrhage (DAH).

Case report
A 31-year-old female presented with cough and hemoptysis. Symptoms started with a cough productive of yellow sputum 4 weeks prior to presentation. One day prior to presentation she had hemoptysis productive of one cup of bright red blood over 24 hours. She denied fever, rash, shortness of breath, joint pain, myalgias, dry eyes, dry mouth, chest pain, orthopnea, or paroxysmal nocturnal dyspnea. Her medical history was notable for an uncomplicated vaginal delivery 5 weeks earlier as well as untreated hepatitis C virus, chronic pain, and posttraumatic stress disorder. Family history was notable for a mother with systemic lupus erythematosus and scleroderma. She was a prior one pack-per-day smoker until 4 years prior to presentation when she switched to flavored nicotine e-cigarettes. She vaped 17 ml of 3 mg/ml nicotine-containing fiery cinnamon flavored e-liquid daily. She denied use of tetrahydrocannabinol (THC) or cannabidiol (CBD) products. Household exposures were notable for a dog, cat, and bearded lizard as well as mold. Her medications included buprenorphine/naloxone, prazosin, and venlafaxine.
On physical examination the patient was afebrile (97.9 � FÞ with a heart rate of 120, a blood pressure of 120/83, a respiratory rate of 22, and an oxygen saturation of 95% while breathing ambient air. She appeared generally well and had no abnormal breath sounds, murmurs, or elevated jugular venous pressure. Chest computed tomography showed nodular ground glass opacities predominantly in the upper and middle lung zones (Fig. 1). The patient was treated for communityacquired pneumonia with ceftriaxone and azithromycin while undergoing a diagnostic evaluation for hemoptysis (Table 1). She underwent flexible bronchoscopy which was notable for progressively more hemorrhagic aliquots on bronchoalveolar lavage (BAL). Over the course of her hospitalization her hemoptysis gradually resolved with cessation of vaping. On follow-up 6 months later, she had no further hemoptysis though she continued to use e-cigarettes.

Discussion
DAH is a rare diagnosis that can be caused by infection, rheumatologic disease, or drug effect. To the best of our knowledge there has been only one prior report of DAH related to e-cigarette use [2]. This case fits the recent CDC definition for a confirmed case of vaping-associated lung injury defined by the use of an e-cigarette 90 days before symptom onset, pulmonary infiltrates on chest computed tomography (CT) scan, absence of viral, bacterial, or fungal infection and no evidence of a cardiac or rheumatologic cause [1,3]. In a recently published case series by Layden and colleagues 80% of patients used THC products [1], and only 17% used nicotine only containing products like our patient (see Table 2). The recent Wisconsin series did not include any cases of DAH. In our case cessation of vaping led to clinical improvement and complete resolution of hemoptysis. Steroids were not administered because hemoptysis had ceased at the time of diagnosis. We present vaping as a cause of diffuse alveolar hemorrhage. The large volume of e-liquid used (~17 ml/daily) may have contributed to the development of DAH in this case. The mechanism of the vaping-associated lung injury remains unknown but has been hypothesized to be related to polycyclic aromatic hydrocarbons, volatile organic chemicals, and oils [1]. This case suggests vaping should be considered as a potential etiology for DAH.

Declaration of competing interest
None.

Disclosures
The manuscript has not been published and is not under consideration for submission at any other journals. This work was supported by grant IK2BX003841 to B.W.R from the U.S. Department of Veterans Affairs.

Author contributions
All authors met the following conditions 1) Substantial contributions to the conception or design of the work; or the acquisition, analysis, or interpretation of data; 2) Drafting the work or revising it critically for important intellectual content; 3) final approval of the version to be published; 4) Agreement to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.