This refers to spongiosis in combination with an intraepidermal eosinophilic infiltrate.  The primary differential diagnoses are:

• Allergic contact dermatitis
• Erythema toxicum neonatorum
• Pemphigus vulgaris and related disorders
• Bullous pemphigoid
• Eosinophilic pustular folliculitis
• Incontinentia pigmenti
• Arthropod bites
• Spongiotic drug eruptions
• Parasitic infestations such as cutaneous larva migrans 

Cases associated with this book:

Eosinophilic spongiosis
Author: Stephen Lyle, M.D., Ph.D.

Conference: DermatopathologyConsultations.com Teaching Collection