Severe Dry Cough Followed by Eosinophilia Without Pulmonary Infiltrates After Dupilumab Treatment in Patients with Severe Asthma: A Series of Five Cases.

Purpose: Dupilumab is known to cause transient, asymptomatic eosinophilia, but in rare cases it can present as eosinophilic pneumonia accompanied by cough. This study reports a distinct manifestation of dupilumab-related eosinophilia presenting as a severe dry cough despite the absence of radiological or clinical evidence of eosinophilic pneumonia. Patients and Methods: A retrospective analysis of clinical data from patients with severe eosinophilic asthma (SEA) treated with dupilumab at the Guangzhou Institute of Respiratory Disease between August 2020 and February 2025 was conducted. Data on clinical manifestations, objective indicators and subjective questionnaires were collected at four time-points: before dupilumab initiation, preceding dupilumab-related cough, during the cough episode, and after cough resolution. Results: Five patients treated with dupilumab (three males and two females with a mean age of 65.6 ± 9.2 years) developed a severe dry cough and marked eosinophilia (1,130-4,050 cells/μL) without radiologic or clinical evidence of eosinophilic pneumonia. The cough began after one to eleven dupilumab courses. Despite the increase in eosinophils, all patients achieved their personal best FEV1 versus baseline. The symptoms resolved with a short course of systemic corticosteroids (in four patients) or antitussive therapy alone (in one patient). Conclusion: Dupilumab-related eosinophilia can manifest as a severe, steroid-responsive coughing despite the absence of parenchymal eosinophilic disease.