Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.17.1A: Nodular dermatitis, granulomatous + 10.17.1B: Collections of histiocytes enveloped by lymphocytes and plasma cells, and brown spores in a multinucleate macrophage = Chromomycosis In a fully developed lesion o…

Differential Diagnosis in Dermatopathology

Erythema nodosum vs. Nodular vasculitis

Infection of skin and subcutaneous tissue by atypical mycobacteria, that is, mycobacteria other than those responsible for tuberculosis and leprosy, expressed clinically as keratotic and crusted papules, plaques, nodules, and tumors that may be punc…

Differential Diagnosis in Dermatopathology

Perforating folliculitis vs. Elastosis perforans serpiginosa

Infection of skin and subcutaneous tissue by atypical mycobacteria, that is, mycobacteria other than those responsible for tuberculosis and leprosy, expressed clinically as keratotic and crusted papules, plaques, nodules, and tumors that may be punc…

Histologic Diagnosis of Inflammatory Skin Diseases

Pyoderma gangrenosum

Pyoderma gangrenosum Synonyms Phagedena goemoetrica Dermatitis gangrenosa Malignant pyoderma Presentation stereotypical Age and sex Adults of both sexes Distribution of lesions Localized usually to the lower extremities; widespread episodically In…

Histologic Diagnosis of Inflammatory Skin Diseases

Sarcoidosis

Sarcoidosis Synonyms Boeck’s disease Boeck sarcoid Benign lymphogranulomatosis Presentation stereotypical Age and sex Young adults of both sexes Distribution of lesions Face and extremities especially Arrangement of lesions Scattered Configu…

Histologic Diagnosis of Inflammatory Skin Diseases

Erythema nodosum leprosum

…are dispersed widely in lobules. Erythema nodosum is devoid of suppuration, whereas erythema nodosum leprosum is typified by zones of suppuration. The infiltrate of inflammatory cells in the reticular dermis of erythema nodosum is scant, whereas that…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.22.1A: Vesicular dermatitis, intraepidermal, spongiotic + 10.22.1B: Hyphae in the cornified layer = Dermatophytosis Were there no hyphae present in the stratum corneum, the differential diagnosis also would include allergic cont…

Histologic Diagnosis of Inflammatory Skin Diseases

Factitious dermatitis and panniculitis

Factitious dermatitis and panniculitis Synonyms Self-induced skin disease Pathomimicry Dermatitis artifacta Munchhausen syndrome Dermatitis passivata Factitial lymphedema (Secretan syndrome) Malingering Self-mutilation Presentation stereotypical Age…

Histologic Diagnosis of Inflammatory Skin Diseases

Acne vulgaris

Synonyms Acne simplex Presentation stereotypical Age and sex Adolescents of both sexes; usually more severe in males. May affect neonates. Distribution of lesions Regions in which large sebaceous units are joined to vellus follicles, i.e., the face,…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

…membranous fat necrosis, as well as of many foam cells 8. No suppuration in the subcutaneous fat 8. Suppuration prominent in the subcutaneous fat, especially in lobules 9. Eosinophils present often and sometimes numerous 9. Eosinophils usually no…