Histologic Diagnosis of Inflammatory Skin Diseases

Nerves

Both somatic sensory and autonomic motor nerves are present in skin (Fig. 1.82). The somatic sensory system mediates sensations of pain, itch, temperature, light touch, discriminative touch, pressure, vibration, and proprioception. Nerves of the aut…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 11.13.1A: Perivascular and interstitial dermatosis, infundibulocentric + 11.13.1B: Small lymphocytes, large abnormal lymphocytes, neutrophils and eosinophils = Lymphomatoid papulosis ¬†Episodically, as shown here, an infiltrate of l…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

…t 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 eosinophi…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

…other; 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 t…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.84.1A: Vasculitis, large-vessel, mixed cell + 10.84.1B: Thrombus within the lumen of an artery situated in the subcutaneous fat and a mix of inflammatory cells in the wall of it = Polyarteritis nodosa ¬†The infiltrate of inflamma…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.15.1A: Nodular dermatitis, granulomatous + 10.15.1B: Histiocytes in a palisade in the upper part of the dermis in conjunction with a perivascular lymphoplasmacytic infiltrate = Crohn’s disease The palisaded granulomas in t…

Histologic Diagnosis of Inflammatory Skin Diseases

Disseminated intravascular coagulopathy

…ophilic 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 coagu…

Differential Diagnosis in Dermatopathology

Discussions

Dermatitis herpetiformis and bullous pemphigoid 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 histo…

Histologic Diagnosis of Inflammatory Skin Diseases

Identification of Basic Patterns: Skin: Fibrosing Dermatitis

See Fig. 5.350 A&B. Figure 5.350 Fibrosing dermatitis. A. Early. B. Late (sclerosis). Fibrosing dermatitis (as well as fibrosing peri-infundibulitis/perifolliculitis and fibrosing panniculitis) results, in every instance, from injury to nonep…

Histologic Diagnosis of Inflammatory Skin Diseases

Limitations of the Algorithmic Method

The algorithmic method proposed in these pages and predicated on patterns histopathologic is intended to be more than just a guide to diagnosis of particular pathologic processes in skin and subcutaneous fat; it is meant to serve as a springboard fo…