Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Dermal Papilla?

“Historically, the hair germ has been defined as a group of cells located at the base of the telogen follicle in close contact with the dermal papilla.” Lavker RM, Miller S, Wilson C, et al. Hair follicle stem cells: their location, ro…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Study By Disease

“Blue nevus” (Jadassohn-Tièche) (Quiz #360) “Blue nevus” (Jadassohn-Tièche) (Quiz #525) “Blue nevus” (Masson’s blue neuronevus) (Quiz #359) “Collagenous” nevus, papillary dermal type* (Quiz #11…

Differential Diagnosis in Dermatopathology

Discussions

Trichoadenoma and microcystic adnexal carcinoma at times resemble each other sufficiently to pose a dilemma diagnostic, even though the former is a hamartoma and the latter an adenocarcinoma. Both may have several findings histopathologic in common:…

Histologic Diagnosis of Inflammatory Skin Diseases

Lymphadenosis benigna cutis

Lymphadenosis benigna cutis Synonyms Borrelial pseudolymphoma Presentation stereotypical Age and sex Any age and either sex Distribution of lesions Localized usually to an ear lobe, the nose, a nipple or areola, or the scrotum; lesions on the ear ar…

Histologic Diagnosis of Inflammatory Skin Diseases

See Classification of Pigmented Lesions

Non-melanocytic lesions Inflammatory Post-inflammatory hyperpigmentation Dermatofibroma Hamartomas Collagenous nevus, papillary dermal type Nevoid hyperkeratosis of the nipple Benign neoplasms Solar lentigo, including lichen planus-like ker…

Histologic Diagnosis of Inflammatory Skin Diseases

Pigmented Lesions

Non-melanocytic lesions Inflammatory Post-inflammatory hyperpigmentation (523, 649) Melanophages in number variable scattered in the papillary dermis, rarely in the upper part of the reticular dermis too. Melanin increased in amount in the epi…

Differential Diagnosis in Dermatopathology

Trichoadenoma vs. Microcystic adnexal carcinoma

An inflammatory process caused by the acarus Sarcoptes scabiei and consisting of papules, papulovesicles, papulopustules, and vesicles, some arranged in linear or curvilinear tracks (burrows). Sometimes nodules are present, especially in the interdi…