The character of the eruption in the erythematous type resembles closely that of erythema multiforme and of urticaria, especially the former. The efflorescences usually make their appearance in crops, and are more or less persistent; fading sooner or later, however, and giving place to new outbreaks. Vesicles are often intermingled, developing from erythematous and erythemato-papular lesions or arising from apparently normal skin.
It may continue in the same type, or change to the vesicular, bullous or other variety.
Describe the papular type of dermatitis herpetiformis.
This is rarely seen as consisting purely of papular lesions, but is commonly associated with the erythematous and vesicular varieties. In a measure it resembles the papular manifestations of erythema multiforme, with a distinct disposition toward group formation. The papules tend, sooner or later, to develop into vesicles, new papular outbreaks occurring from time to time; or the whole eruption changes to the vesicular or other type of the disease. It is not a common type.
Describe the vesicular type of dermatitis herpetiformis.
This is the common clinical type of the disease, and is characterized by pin-head to pea-sized, rounded or irregularly-shaped, distended or flattened and stellate vesicles, occurring, for the most part, in irregular and segmental groups of three or more lesions, seated either upon apparently normal integument or upon hyperæmic or inflammatory skin. They exhibit no tendency to spontaneous rupture, but after remaining a shorter or longer time, are broken or disappear by absorption. The lesions tend to appear in crops. It may, as it not infrequently does, continue in the same type, or it may become more or less erythematous or bullous in character. In not a few instances pustules, few or in numbers, are at times intermingled.
Describe the pustular type of dermatitis herpetiformis.
This is rare. It is similar in its clinical characters to the vesicular type, except that the lesions are pustular. It is met with, as a rule, in association with the vesicular and bullous varieties of the disease.
Describe the bullous type of dermatitis herpetiformis.
The bullous expression of the disease is usually of a markedly inflammatory nature, often innumerable blebs, small and large, appearing almost continuously, and in some instances involving the greater part of the surface. The lesions arise from erythematous skin, from preëxisting vesicles or vesicular groups, or from apparently normal integument. There is a marked disposition to appear in clusters. A change of type to the erythematous or vesicular varieties is not unusual.