Immunobullous dermatoses may present with urticarial lesions, blisters, erosions, or pustules. IgA-mediated disease is characterized by annular lesions with a “string of pearls” morphology—bullous in the case of linear IgA bullous dermatosis and pustular or erosive in the case of IgA pemphigus. Pemphigoid typically presents with tense blisters forming on erythematous patches or urticarial plaques. Pemphigus vulgaris often initially appears with oral erosions, but can progress to widely denuded areas of skin. In contrast, pemphigus foliaceus presents with superficial erosions and adherent crusts that resemble macerated cornflakes allowed to dry at the bottom of the bowl. Pemphigus vegetans is characterized by localized, moist, heaped-up crusts, sometimes studded with pustules. Dermatitis herpetiformis presents with intense itching with excoriation and erosions clustered on the posterior scalp, extensor surfaces, and buttocks. Itching is intense, so it is rare to identify intact blisters. This portion of the atlas will guide you through the various clinical presentations of bullous disorders of the skin.