Elevation of peripheral blood eosinophils during dupilumab treatment for atopic dermatitis is associated with baseline comorbidities and development of facial redness dermatitis and ocular surface disease

Introduction Transient eosinophilia is not uncommon in patients with moderate-to-severe atopic dermatitis (AD) treated with dupilumab. Methods A retrospective, single center, observational study was conducted to assess the difference in terms of absolute eosinophil count (AEC) change at 4 months and at 12 months, relative to the baseline, in predefined subgroups of patients affected by moderate-to-severe AD treated with dupilumab. Results Complete data for 373, 289 and 210 patients were available at the baseline, 4 months and 12 months, respectively. Patients with a history of conjunctivitis (n = 152) had greater increases in AEC at 4 months as compared with those (n = 137) who did not (+16%vs0%,p = 0.01). Patients with food allergies (n = 46) showed similar increases (+39%vs + 5%, p = 0.01). Patients experiencing facial redness dermatitis on dupilumab (n = 46) had greater increases in AEC at 4 months than those (n = 243) who did not (+40%vs + 5%, p = 0.03). Patients that had dupilumab-induced ocular surface disease (n = 44) had greater increases in AEC at 4 months than those (n = 245) who did not (+43%vs + 5%, p = 0.01). Conclusions Atopic comorbidities are associated with a paradoxical increase in AEC at 4 months in AD patients treated with dupilumab. Patients experiencing dupilumab-related ocular surface disease or facial redness dermatitis also have remarkable increases in AEC at 4 months.