Histologic Diagnosis of Inflammatory Skin Diseases

Nerves

…rmis, small discrete erosions or ulcerations, and deposits of fibrin or a locus of fibrosis immediately beneath the epidermis, and the latter being lichen simplex chronicus, prurigo nodularis, and picker’s nodule, which share findings of compac…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…in the form of either thrombi in the lumen, as shown here, or fibrin in the wall of venules. The vasculitis is an epiphenomenon, affecting only very few vessels and is not analogous to authentic vasculitides, such as those known as leukocytoclastic,…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

…usually 1. No nuclear “dust” of neutrophils 2. Fibrin in and around the wall of venules 2. No fibrin in and around the wall of small vessels 3. No thrombi 3. Thrombi in small vessels 4. Eosinophils present commonly 4. No eosinophil…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

…ther; degeneration of collagen bundles slight and deposits of fibrin little 6. Histiocytes form palisades around zones of marked degeneration of collagen and, sometimes, a tad of fibrin; no mucin in these foci 7. No plasma cells or only a few of th…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…e = Temporal arteritis  In polyarteritis nodosa, by contrast, fibrin often is present in the wall of the affected artery and the infiltrate of inflammatory cells in the adjacent lobules of adipocytes is scant. The section pictured comes from a biopsy…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…his fundamentally small-vessel vasculitis is characterized by fibrin in the wall of venules and thrombi in lumen of them. In addition, there are signs of suppuration, ulceration, and scale-crust. This is but one of several cutaneous manifestations of…

Histologic Diagnosis of Inflammatory Skin Diseases

Disseminated intravascular coagulopathy

…philic material. Laboratory confirmation Decreased levels of fibrinogen, platelets, prothrombin, and other factors of coagulation are notable, as well as is elevated split products of fibrin. Cause and mechanism The cause is activation of the coagul…

Differential Diagnosis in Dermatopathology

Discussions

…id share several findings, namely, subepidermal vesiculation, fibrin in subepidermal spaces, and a mix of inflammatory cells, among them lymphocytes and some neutrophils and eosinophils. The changes histopathologic enumerated at the outset of this ch…

Histologic Diagnosis of Inflammatory Skin Diseases

Identification of Basic Patterns: Skin: Fibrosing Dermatitis

…result being ulceration and granulation tissue atop which are fibrin and crust, and at the side of which is pseudocarcinomatous (infundibular) proliferation of keratocytes. Figure 5.355 A&B. Repair of chondrodermatitis nodularis helicis: fibro…

Histologic Diagnosis of Inflammatory Skin Diseases

Limitations of the Algorithmic Method

…lar section of tissue show signs of vasculitis in the form of fibrin in the wall of venules or thrombi in the lumen of them, never is that the case for “lymphocytic vasculitis” in which only one or two venules in a section show evidence o…