Foti, C; Bonamonte, D; Bosco, A; Angelini, G; ,
Eczematous dermatosesEczematous dermatoses, that are everyday observations in clinical practice, are induced by various factors of an exogenous and endogenous nature, that generally act in combination. A helpful classification subdivides the various forms of eczema into exogenous (irritant contact dermatitisIrritant contact dermatitis, allergic contact dermatitisAllergic contact dermatitis, microbial eczemaMicrobial eczema, dermatophytide) and endogenous (atopic eczema, nummular eczemaNummular eczema, pompholyxPompholyx, asteatotic eczemaAsteatotic eczema, gravitational eczema, pityriasis alba, juvenile plantar dermatosis, seborrhoeic dermatitisSeborrhoeic dermatitis). However, it must be borne in mind that external triggering factors are associated with an inherited predisposition in the induction of a single disease. Nummular (discoid) eczema, that is not a precise etiological entity, is clinically characterized by coin-shaped or oval lesions with well-defined borders on the trunk and limbs. It is essential to stress that atopic dermatitisAtopic dermatitis and allergic contact dermatitisAllergic contact dermatitis can present with the same clinical aspects. Asteatotic (xerotic) eczema is usually observed in childrenChildren and elderly subjects with minimal clinical signs (modest erythema and pityriasiforme desquamation) affecting most often the legs. Gravitational (stasis) eczema involves the lower third of the legs of middle-aged or elderly subjects. Pityriasis alba, that is characterized by hypopigmented patches preceded by mild erythema and scaling, is more often a manifestation of atopic dermatitisAtopic dermatitis and is observed above all between the ages of 3 and 16 years in both sexes on the trunk, cheeks, and arms. Juvenile plantar dermatosis has been described almost exclusively in childrenChildren who actively practice sports: the plantar surface of the forefoot appears smooth and shiny, with ragades at the flexor folds of the toes. PompholyxPompholyx, that is a recurrent eruption of vesicles on non erythematous skin of the palms and soles, may occur at any age, although it is more common in young adults; the cronicity of the disease can favour the occurrence of contact allergyContact allergy. Seborrhoeic dermatitisSeborrhoeic dermatitis, that is characterized by a peculiar clinical picture and sitesSites (scalp, face, and upper trunk), has a incidence of 3–5% in the general population.