Eosinophilic dermatoses are a group of disorders with various etiologies that are distinguished by eosinophilic infiltration of the skin and/or mucous membranes, with or without accompanying blood eosinophilia. A non-univocal categorization system reflects the vast variety of dermatological manifestations of this spectrum, including nodules and plaques, pustules, blisters, ulcers, and urticarial lesions. The study classified eosinophilic dermatoses into six groups depending on their main anatomic degree of involvement: (1) epidermal; (2) dermal-epidermal junction; (3) dermal; (4) hypodermis and muscle fascia; (5) pilosebaceous unit; and (6) vascular/perivascular. 

Researchers discuss the clinicopathologic features and management of diseases belonging to each group, with a focus on (1) pemphigus herpetiformis and atopic dermatitis as epidermal prototypes; (2) bullous pemphigoid as prototypic eosinophilic dermatosis of the dermal-epidermal junction; and (3) eosinophilic cellulitis (Wells syndrome), hypereosinophilic syndromes; (5) eosinophilic pustular folliculitis as a model of the pilosebaceous unit involvement; and (6) granuloma faciale, angiolymphoid hyperplasia with eosinophilia, and eosinophilic granulomatosis with polyangiitis, belonging to the vascular/perivascular group.

Reference: https://link.springer.com/article/10.1007/s40257-020-00520-4