Differential Diagnosis in Dermatopathology

Acne vulgaris, erythematous papule vs. Rosacea, erythematous papule

An inflammatory disease caused by the spirochete Borrelia burgdorferi that manifests itself in the skin as erythematous lesions with figurate shapes, e.g., (round, ellipsoid, and arcuate) (erythema chronicum migrans), pseudolymphomatous nodules (lym…

Histologic Diagnosis of Inflammatory Skin Diseases

Deep fungal infections

Deep fungal infections Synonyms Mycetoma Subcutaneous mycoses Dermal mycoses Presentation stereotypical Age and sex Any age, both sexes Distribution of lesions Localized or widespread; some infections favor exposed sites; internal organs sometimes…

Histologic Diagnosis of Inflammatory Skin Diseases

Behçet’s Disease

Behçet”s disease Synonyms Aphthosis Behçet Aphthosis Presentation stereotypical Age and sex Onset usually in the third decade of life with male predominance Distribution of lesions Face for acneiform lesions, lower extremities for panniculit…

Histologic Diagnosis of Inflammatory Skin Diseases

Erythema nodosum leprosum

Erythema nodosum leprosum Features clinical Red nodules or plaques that may develop anywhere but especially the thighs and legs Findings histopathologic Early Suppurative lobular panniculitis, focal at first and then diffuse Patchy zones of extensi…

Histologic Diagnosis of Inflammatory Skin Diseases

Leishmaniasis

Leishmaniasis Synonyms Leishmaniosis Presentation stereotypical Age and sex Young adults of both sexes Distribution of lesions Localized in Oriental sore, widespread in the mucocutaneous and post-kala-azar types, and disseminated in the anergic cuta…

Histologic Diagnosis of Inflammatory Skin Diseases

Rosacea

Rosacea Synonyms Gutta rosea Presentation stereotypical Age and sex Young and middle-aged adults, usually Caucasian women Distribution of lesions Center of the face in vertical and horizontal directions, i.e., nose, forehead, cheeks, and chin Indivi…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.59.1A: Perivascular dermatitis, interface, focally lichenoid + 10.59.1B: Beneath a thinned epidermis, obscuration partially of the dermoepidermal junction by an infiltrate of lymphocytes and histiocytes = Lichen niti…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Wegener’s Granulomatosis?

“Inside the nose besides extensive necrosis, there is a cell-rich granulomatous tissue with granulomatous epithelioid cell foci which surround the vessels. . . . In both lungs: infarct-like necrosis in which one finds severe changes in the ve…