Histologic Diagnosis of Inflammatory Skin Diseases

Lichen planus

…sions are distributed mostly on sites exposed to sunlight and often display a plug of horn in widened infundibula, healing at times with a hypopigmented atrophic center and hyperpigmented border. Lichenoid purpura of Gougerot and Blum: Lesions usuall…

Differential Diagnosis in Dermatopathology

Nevus verrucosus vs. Acanthosis nigricans

A malignant neoplasm of keratinocytes that when present as a keratotic macule or papule on skin damaged badly by sunlight is referred to as solar keratosis. When present as a plaque it is termed Bowen’s disease, and when present as many papule…

Differential Diagnosis in Dermatopathology

Discussions

…etween the persistent pigmented purpuric lichenoid dermatitis of Gougerot and Blum and the plaque stage of mycosis fungoides may be exceedingly difficult at times because both diseases are made up of lymphocytes arrayed in band-like fashion in the up…

Dermatology Practical & Conceptual

An itchy rash in a young Caucasian woman

…erpetiformis, linear IgA disease or confluent and reticulated papillomatosis of Gougerot and Carteaud [3]. Clinicopathologic correlation is the key to diagnosis. BÖer and Ackerman, in 2003, defined criteria for histopathologic diagnosis of prurigo pi…

Dermatology Practical & Conceptual

Study By Disease

…4) Condyloma acuminatum (Quiz #510) Confluent and reticulated papillomatosis of Gougerot and Carteaud (Quiz #629) Congenital melanocytic nevus (Quiz #80) Congenital melanocytic nevus on a special site (umbilicus) (Quiz #88) Congenital melanocytic nev…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Pseudomalignancies?

…es are also precanceroses. The histological substrate is that of pseudocarcinomatous epithelial hyperplasia with inflammation. The following diseases are so-called pseudocanceroses: Papillomatosis cutis carcinoides Florid oral papillomatosis Epitheli…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Capillaritis?

…des, to wit, Schamberg’s disease, the lichenoid purpura of Gougerot and Blum (lichen aureus), and the eczematid-like purpura of Doucas and Kapetanakis. Two serious problems are inherent in the concept of capillaritis as it relates to the persis…

Differential Diagnosis in Dermatopathology

Discussions

…(skin-“tags,” acrochordons). They are aberrations of the papillary dermis, i.e., connective tissue nevi. The confluent and reticulated papillomatosis of Gougerot and Carteaud resembles acanthosis nigricans closely histopathologically; whe…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Benign, Pseudo, or Malignant Acanthosis Nigricans?

…interrupted by prominent creases that represent exaggerations of normal skin markings. Palpation reveals them to possess a smooth, soft, and “velvety” quality. Acanthosis nigricans is characterized histopathologically by papillomatosis, i…

Dermatology Practical & Conceptual

Pigmented tumor in the nostril

…nspecific chronic inflammatory infiltration, with no evidence of cellular atypia. The epidermis revealed hyperkeratosis, acanthosis, and papillomatosis with a sharp dermarcation line. Polymerase chain reaction (PCR) for human papillomavirus (HPV) was…