Histologic Diagnosis of Inflammatory Skin Diseases

Necrobiosis lipoidica

…omenclature, necrobiosis lipoidica is unrelated to necrobiotic xanthogranuloma. More often than not, necrobiosis lipoidica is a manifestation of diabetes, whereas necrobiotic xanthogranuloma is an expression of paraproteinemia. The yellow color impar…

Histologic Diagnosis of Inflammatory Skin Diseases

Urticaria pigmentosa

Urticaria pigmentosa Synonyms Mastocytosis Presentation stereotypical Age and sex All ages and both sexes, but mostly nodules and blisters in infants and children, and mostly macules and papules in adults Distribution of lesions Localized or widespr…

Histologic Diagnosis of Inflammatory Skin Diseases

Xanthomas

Xanthomas Presentation stereotypical Age and sex Adults of both sexes Distribution of lesions Localized or widespread Individual lesions Macules, papules, plaques, and nodules Course Some lesions, e.g., eruptive xanthomas, involuting when serum lipi…

Histologic Diagnosis of Inflammatory Skin Diseases

Algorithms Predicated on “Nonspecific” Findings

In this section, algorithms used to reach specific diagnosis are predicated on “nonspecific” findings recognized best at higher magnification. Other changes requisite for specific diagnoses, i.e., denominators that are essential, then ar…

Histologic Diagnosis of Inflammatory Skin Diseases

Confusing Terms (to be Avoided Scrupulously)

APOPTOSIS [Gk. apo- (away from) + ptosis (a falling)]: Reputed to be a specific type of cell death in which dead cells are said to undergo fragmentation by implosion with subsequent phagocytosis of nuclear debris (Fig. 3.40). The process is claimed…

Dermatology Practical & Conceptual

Dermatoscopy: What is your diagnosis?

…quiz The correct answer to the quiz in the April 2012 issue is xanthogranuloma. Please see article 3 of this issue of Dermatology Practical and Conceptual for a detailed description of xanthogranuloma with dermatoscopic/dermatopathologic correlation…

Histologic Diagnosis of Inflammatory Skin Diseases

Applicable Terms

ABSCESS [L. abscessus (a going away)]: Clinically, a circumscribed collection of pus and histopathologically a localized collection of neutrophils. An abscess may form in the epidermis, both surface and infundibular, eccrine ducts, dermis, and subcu…

Histologic Diagnosis of Inflammatory Skin Diseases

Study By Disease

…dica (Quiz #490) Necrobiosis lipoidica (Quiz #491) Necrobiotic xanthogranuloma (Quiz #533) Necrobiotic xanthogranuloma (Quiz #680) Neuroendocrine carcinoma (Quiz #730) Neurofibroma (Quiz #527) Neurofibroma (Quiz #528) Neurofibroma (Quiz #529) Neurofi…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 11.24.1A: Nodular dermatosis + 11.24.1B: Foamy histiocytes in a papule = Xanthoma  A xanthoma differs from a xanthogranuloma by being made up of a nearly pure population of foamy histiocytes, practically none of which are multinucl…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.24.1A: Nodular and diffuse dermatitis, granulomatous + 10.24.1B: Lymphocytes and plasma cells in a collection of histiocytes that exhibit abundant pale cytoplasm = Destombes-Rosai-Dorfman disease Histiocytes with lar…