An Approach to Skin Diseases Associated with Eosinophilia

Eosinophilic skin disorders are encountered frequently in both inpatient and outpatient settings. The cause might be allergic, autoimmune bullous, infectious, hematologic, or hypereosinophilic syndromes, and workups should vary depending on the clinical presentation.

In a retrospective study, investigators reviewed records from 453 patients with rashes and eosinophilia who were referred to a Swiss dermatology clinic. Mild eosinophilia (500–1000 cells/µL) generally was seen in younger atopic patients who had eczema or infectious diseases, such as cutaneous larva migrans or scabies. Moderate eosinophilia (1000–1500 cells/µL) was associated most often with generalized skin lesions that often blistered, age >70, and autoimmune bullous disease. Severe eosinophilia (>1500 cells/µL) usually was associated with hypereosinophilic syndrome, drug hypersensitivity, or malignancy (especially chronic lymphocytic leukemia). Patients with severe eosinophilia often had other abnormalities, such as abnormal blood counts, elevated lactate dehydrogenase, and abnormal computed tomography findings.