Histologic Diagnosis of Inflammatory Skin Diseases

Lichen planus

…histopathologic Early Superficial perivascular infiltrate of lymphocytes Lichenoid infiltrate of lymphocytes, patchy at first and then confluent Infiltrate obscures the dermoepidermal junction in conjunction with vacuolar alteration and individual n…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…5.1A: Perivascular and interstitial dermatitis + 10.5.1B: Lymphocytes and eosinophils around venules, and neutrophils in the interstitium in conjunction with degeneration of bundles of collagen focally = Response to an arthropod assault¬† Lysosoma…

Histologic Diagnosis of Inflammatory Skin Diseases

Applicable Terms

…ed” tubercle), and that surrounded by a dense mantle of lymphocytes, and sometimes plasma cells, is designated tuberculoid. Sarcoidal granulomas are found not only in sarcoidosis, but also in foreign body responses to materials such as silica a…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…11.11.1A: Perivascular dermatosis, lichenoid + 11.11.1B: Lymphocytes, many necrotic keratocytes and a subepidermal cleft = Lichen planus-like keratosis, early ¬†Because lichen planus-like keratosis often is misinterpreted clinically as basal-cell…

Histologic Diagnosis of Inflammatory Skin Diseases

The Algorithmic Method

…on, of the kind or kinds of inflammatory cells (or neoplastic lymphocytes, Langerhans” cells, and mast cells that, at first blush, may appear to be inflammatory cells) that make up the infiltrate. Remarkable as it may seem, specific types of in…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…+ 10.60.1B: Obscuration of the dermoepidermal junction by lymphocytes, jagged acanthosis, wedge-shaped hypergranulosis, and compact orthokeratosis = Lichen planus, early Zones of wedge-shaped hypergranulosis are centered around acrosyringia and t…

Histologic Diagnosis of Inflammatory Skin Diseases

Arthropod assaults

…matory cells in response to a “bite” of an insect Lymphocytes and eosinophils around venules, and eosinophils scattered in the interstitium of the reticular dermis; a few neutrophils may be discernible Slight edema of the papillary dermis…

Histologic Diagnosis of Inflammatory Skin Diseases

Errors and Reasons

…iculosis,” i.e., a lymphoma, such as mycosis fungoides; lymphocytes never are strikingly atypical. Error: “Acute” and “chronic” inflammatory cells are characterizations accurately of neutrophils and eosinophils on one ha…