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

An 18‐year‐old man was admitted to our hospital with pneumonia 4 days after he initiated vaping. The patient did not show improvement after ceftriaxone and azithromycin treatment. The cell count of the bronchoalveolar lavage fluid (BALF) revealed 64% eosinophils and 18% lymphocytes. Based on the BALF findings, the patient met the current diagnostic criteria and was diagnosed with vaping‐induced acute eosinophilic pneumonia (AEP). AEP caused by nicotine‐free vaping is rare in Japan. Thus, in cases of AEP, the patient's history of cigarette smoking as well as vaping should be considered. Vaping has become popular among young people and adolescents in Japan because it is easy to obtain and is legally ambiguous. We encountered a case of acute eosinophilic pneumonia caused by nicotine‐free vaping and report our findings to highlight the safety concerns associated with vaping.