No abstract

A 73-year-old woman in complete remission from localized small-cell lung cancer associated with Lambert-Eaton myasthenic syndrome (LEMS) 22 years earlier was referred to our hospital and diagnosed with non-small-cell lung cancer. After three courses of pembrolizumab, an immune checkpoint inhibitor, the patient complained of muscle weakness, fatigue, ptosis, and dysarthria. The anti-voltage-gated calcium channel antibody level was elevated, and waxing was observed on a high-frequency repetitive stimulation test using an electromyogram. We diagnosed her with recurrence of LEMS as an immune-related adverse event (irAE) induced by pembrolizumab. After intravenous immunoglobulin therapy, the patient's symptoms improved, and she was discharged.

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.