Histologic Diagnosis of Inflammatory Skin Diseases

Dermatofibroma

…absence of trauma. Desmoplastic melanoma is more asymmetrical, subtly variegate in color, and unaffiliated with a “dimple sign.” Spitz’s nevus may be red, orange, or pink, as well as brown or black, but it is not firm unless it is w…

Differential Diagnosis in Dermatopathology

Images

Spitz’s Nevus, Compound Type Melanoma…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

Spitz’s Nevus, Compound Type Melanoma 1. Symmetric 1. Asymmetric 2. Sharp circumscription 2. Poor circumscription 3. Maturation of melanocytes (decrease in size of aggregations and of nuclei) with descent progressive 3. No maturation w…

Histologic Diagnosis of Inflammatory Skin Diseases

Lymphadenosis benigna cutis

…cal Lymphoma may be indistinguishable. When the breast is the site affected, primary carcinoma must be considered. Tick “bite” and assaults by other arthropods may be identical. Spitz’s nevus often presents itself as a pink, red, o…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

Dermatofibroma Desmoplastic Spitz’s nevus 1. Acanthotic epidermis often associated with induction of folliculo-sebaceous units 1. Little or no acanthosis; no induction of folliculo-sebaceous units 2. Epidermis often thinned above the cen…

Differential Diagnosis in Dermatopathology

Images

Dermatofibroma Desmoplastic Spitz’s nevus

Histologic Diagnosis of Inflammatory Skin Diseases

Acrodermatitis chronica atrophicans

Acrodermatitis chronica atrophicans Presentation stereotypical Age and sex Middle aged to elderly women especially Distribution of lesions Distal part of extremities, particularly of legs; nodules develop especially near knees and elbows Configurati…

Histologic Diagnosis of Inflammatory Skin Diseases

Polyarteritis nodosa

Polyarteritis nodosa Synonyms Periarteritis nodosa Panarteritis nodosa Kussmaul-Maier disease Kussmaul-Maier syndrome Polyarteritis acuta nodosa Presentation stereotypical Age and sex Men mostly Distribution of lesions Bilateral, particularly on the…

Differential Diagnosis in Dermatopathology

Granuloma annulare vs. Eruptive xanthoma

Deposits of lipid in the skin and sometimes in subcutaneous tissues as a consequence often, but not always, of hyperlipidemia. The lipid deposits are expressed as yellowish papules and plaques, and nodules and tumors….

Differential Diagnosis in Dermatopathology

Discussions

…histiocytes positioned mostly in the upper part of the dermis, sometimes in palisaded array and sometimes as solitary units splayed between bundles of collagen. Moreover, both conditions exhibit lymphocytes around venules and extracellular deposits o…