Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Primary and Secondary Lesions?

“Some of the appearances observed in cutaneous diseases are caused directly by the deposition of morbid products in the skin. These bear the name of Primary symptoms or eruptions, Efflorescentiae cutaneae primariae. But these eruptions often…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.50.1A: Perivascular dermatitis, interface, and vesicular dermatitis, intraepidermal, spongiotic + 10.50.1B: Eosinophils in contiguity with numerous necrotic keratocytes = Incontinentia pigmenti, vesicular stage Inflammatory cell…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.58.1A: Perivascular and interstitial dermatitis + 10.58.1B: Neutrophils and copious quantities of nuclear “dust” of neutrophils in association with many extravasated erythrocytes = Leukocytoclastic vasculitis, early…

Histologic Diagnosis of Inflammatory Skin Diseases

Leukocytoclastic vasculitis

…, or both together in the same section of tissue. Subepidermal vesicles alone occur almost always as a consequence of extensive edema of the papillary dermis and intraepidermal vesicles from a combination of spongiosis and ballooning. A tense intraep…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.60.1A: Perivascular dermatitis, interface, focally lichenoid + 10.60.1B: Obscuration of the dermoepidermal junction by lymphocytes, jagged acanthosis, wedge-shaped hypergranulosis, and compact orthokeratosis = Lichen planus, ear…

Histologic Diagnosis of Inflammatory Skin Diseases

Study By Disease

“Blue nevus” (Jadassohn-Tièche) (Quiz #360) “Blue nevus” (Jadassohn-Tièche) (Quiz #525) “Blue nevus” (Masson’s blue neuronevus) (Quiz #359) “Collagenous” nevus, papillary dermal type* (Quiz #11…

Differential Diagnosis in Dermatopathology

Discussions

Darier’s disease and Grover’s disease have several findings histopathologic in common, among them foci of acantholytic dyskeratotic cells in the epidermis and a superficial perivascular infiltrate of inflammatory cells, usually lymphocyt…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

Urticarial reaction to an arthropod assault Urtica 1. Marked edema of the papillary dermis sometimes 1. No edema noticeable in the papillary dermis 2. Subepidermal vesicle sometimes secondary to marked edema of the papillary dermis 2. No subep…