Histologic Diagnosis of Inflammatory Skin Diseases

Collagen

More than 70% of the dry weight of the normal dermis consists of collagen (Fig. 1.79). The major collagens are Type I and Type III. Type I collagen has a molecular mass of about 290 KDa and accounts for approximately 80% of the total amount of colla…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…ted with elastophagocytosis is given a different name, to wit, actinic granuloma. 10.15.2A: Nodular dermatitis, granulomatous + 10.15.2B: Histiocytes in palisaded array around foci of degenerated collagen and necrosis of inflammatory cells…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Epidermal Cyst and Epidermoid Cyst?

“Epidermoid cyst. Synonym: Sebaceous cyst, steatoma, epithelial cyst. Definition: A cyst containing keratin and its breakdown products, surrounded by an epidermoid wall.” Mackie RM. Epidermal skin tumors. In: Champion RH, Burton JL, Eb…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…12B: A band of histiocytes, some of them multinucleate, around squamous epithelium that, in turn, surrounds cellulose = Foreign body reaction to a splinter The splinter came to be surrounded by squamous epithelium by virtue of epidermis, either surfa…

Histologic Diagnosis of Inflammatory Skin Diseases

Porphyria cutanea tarda

Porphyria cutanea tarda Presentation stereotypical Age and sex Young and middle-aged adults of both sexes, but mainly women taking estrogens or who are alcoholic Distribution of lesions Blisters on dorsa of hands and feet, pigmentary alterations and…

Differential Diagnosis in Dermatopathology

Photoallergic dermatitis vs. Phototoxic dermatitis

An inflammatory process that results from either topical or systemic sensitization coupled with the effects of ultraviolet light. The lesions, all of which occur in photodistribution, are macules, papules, and blisters that resolve with crusts….

Differential Diagnosis in Dermatopathology

Discussions

…gstanding photoallergic dermatitis. The face of a patient with actinic reticuloid often resembles that of a lion (leonine), as does that of some patients with lymphoma or leukemia and, stereotypically, those with lepromatous leprosy. In brief, actini…

Histologic Diagnosis of Inflammatory Skin Diseases

Lupus erythematosus

…culitis made up mostly of lymphocytes but also often of plasma cells; nuclear “dust” of lymphocytes (“tangible bodies”) sometimes prominent Patchy sclerosis in association with the infiltrate of mononuclear cells, giving the a…

Histologic Diagnosis of Inflammatory Skin Diseases

Lipodystrophy

Lipodystrophy Synonyms Lipoatrophy Wucher atrophy Presentation stereotypical Age and sex Females, first decade of life Distribution of lesions Upper half of body in the “partial” expression of the process and widespread in the “t…