Chapter 052. Approach to the Patient with a Skin Disorder (Part 2) Table 52-2 Description of Secondary Skin Lesions Lichenification: A distinctive thickening of the skin that is characterized by accentuated skin-fold markings. Scale: Excessive accumulation of stratum corneum. Crust: Dried exudate of body fluids that may be either yellow (i.e., serous crust) or red (i.e., hemorrhagic crust). Erosion: Loss of epidermis without an associated loss of dermis. Ulcer: Loss of epidermis and at least a portion of the underlying dermis. Excoriation: Linear, angular erosions that may be covered by crust and are caused by scratching. Atrophy: An acquired loss of substance. In the skin, this may appear as a depression with intact epidermis (i.e., loss of dermal or subcutaneous tissue) or as sites of shiny, delicate, wrinkled lesions (i.e., epidermal atrophy). Scar: A change in the skin secondary to trauma or inflammation. Sites may be erythematous, hypopigmented, or hyperpigmented depending on their age or character. Sites on hair-bearing areas may be characterized by destruction of hair follicles. Table 52-3 Common Dermatologic Terms Alopecia: Hair loss; it may be partial or complete. Annular: Ring-shaped lesions. Cyst: A soft, raised, encapsulated lesion filled with semisolid or liquid contents. Herpetiform: Grouped lesions. Lichenoid: Violaceous to purple, polygonal lesions that resemble those seen in lichen planus. Milia: Small, firm, white papules filled with keratin. Morbilliform: Generalized, small erythematous macules and/or papules that resemble lesions seen in measles. Nummular: Coin-shaped lesions. Poikiloderma: Skin that displays variegated pigmentation, atrophy, and telangiectases. Polycyclic: A configuration of skin lesions formed from coalescing rings or incomplete rings. Pruritus: A sensation that elicits the desire to scratch. Pruritus is often the predominant symptom of inflammatory skin diseases (e.g., atopic dermatitis, allergic contact dermatitis); it is also commonly associated with xerosis and aged skin. Systemic conditions that can be associated with pruritus include chronic renal disease, cholestasis, pregnancy, malignancy, thyroid disease, polycythemia vera, and delusions of parasitosis. Figure 52-3 A schematic representation of several common primary skin lesions (see Table 52-1). . Chapter 052. Approach to the Patient with a Skin Disorder (Part 2) Table 52-2 Description of Secondary Skin Lesions Lichenification: A distinctive thickening of the skin that is characterized. Pruritus: A sensation that elicits the desire to scratch. Pruritus is often the predominant symptom of inflammatory skin diseases (e.g., atopic dermatitis, allergic contact dermatitis); it is also. their age or character. Sites on hair-bearing areas may be characterized by destruction of hair follicles. Table 52-3 Common Dermatologic Terms Alopecia: Hair loss; it may be partial or