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Vesicular palmoplantar eczema is a dermatitis of the hands and feet characterized by small to large blisters clinically and spongiotic vesicles histologically. It can manifest as either an acute or a chronic dermatitis, or both. Because clinical and histologic presentations of the variants of hand dermatitis, including vesicular palmoplantar eczema, often overlap, making a precise diagnosis can be difficult. For example, patients with pompholyx, the most acute form of vesicular palmoplantar eczema, have been noted to have higher incidence rates of both atopy and contact dermatitis than controls.
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With the preceding caveat in mind, vesicular palmoplantar eczema can be divided into four categories: (1) pompholyx, (2) chronic vesiculobullous hand dermatitis, (3) hyperkeratotic hand dermatitis, and (4) id reactions (see Chapter 17). These conditions can be grouped under the category of endogenous hand dermatitis, in contrast to dermatitis clearly caused by exogenous factors such as contact allergy or irritation.
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Pompholyx is a term best reserved for acute explosive outbreaks of small to large vesicles and bullae on the palms and soles. It tends to occur more often in the spring and fall, and may be associated with stress. Other etiologic factors are less well established. Cheiropompholyx and podopompholyx are terms occasionally used to describe cases affecting the palms or soles, respectively. Chronic vesiculobullous hand dermatitis, also known as dyshidrotic hand eczema or dyshidrotic hand dermatitis, is usually characterized by small vesicles on the lateral aspects of the fingers. “Dyshidrosis,” a dysfunction of the sweat gland, was long postulated to be a cause, but its role has been subsequently disproved. However, the terminology persists and is commonly used. A third category is chronic hyperkeratotic hand dermatitis, an entity that generally occurs on the central palms. Unlike the other classifications of vesicular palmoplantar eczema, vesicles do not dominate the clinical presentation. However, the spongiosis observed histologically is indistinguishable from the other categories. An id reaction is a vesiculobullous dermatitis, generally appearing on the lateral aspects of the fingers, elicited by an infection elsewhere in the body. The most common cause is a fungal infection. Treatment of the underlying causative factor usually leads to resolution. Endogenous hand dermatitis can be exacerbated by exogenous factors, most notably irritant dermatitis and allergic contact dermatitis. In addition, atopy may in some cases predispose to the development of vesicular palmoplantar eczema.
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Differences in classification and definition have made it difficult to assess the true incidence of the endogenous hand disorders. Most studies have ...