Erythema nodosum followed by eosinophilic pneumonia as an adverse effect of dupilumab treatment in a patient with severe asthma

Dupilumab is a monoclonal antibody that has recently been introduced for the treatment of asthma. It has the potential to significantly alter the progression and severity of T2 -dependent diseases, including severe asthma. However, dupilumab can cause transient hypereosinophilia. In rare cases, hypereosinophilia can reach high levels and manifest with clinical symptoms. We present the case of a female patient who presented with hypereosinophilia of almost 5000 cells/μL accompanied by erythema nodosum during dupilumab treatment. After stopping and then restarting dupilumab, the patient developed eosinophilic pneumonia. This case highlights the need to monitor blood eosinophil count along with clinical and radiological symptoms in patients receiving dupilumab.