Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.82.1A: Perivascular dermatitis, slightly psoriasiform + 10.82.1B: Alternation of orthokeratosis and parakeratosis in vertical and horizontal directions above a prominent granular zone = Pityriasis rubra pilaris, fully developed…

Dermatology Practical & Conceptual

From the Dermatologikum Hamburg: Quiz

The patient A 78-year-old man presented with a keratotic and crusted plaque on the scalp (Figure 1). He had a history of multiple actinic keratoses with various attempts at treatment. The lesion was excised under the clinical diagnosis of squamous c…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.61.1A: Perivascular dermatitis, spongiotic lichenoid + 10.61.1B: Lymphocytes mostly, in conjunction with scale-crusts that contain neutrophils = Lichen striatus ┬áThe presence of a lichenoid infiltrate telegraphs that this is not…

Histologic Diagnosis of Inflammatory Skin Diseases

Seborrheic dermatitis

Seborrheic dermatitis Synonyms Seborrhoeic dermatitis Seborrheic eczema Unna disease Presentation stereotypical Age and sex Young adults especially and males in particular Distribution of lesions Face, scalp, retroauricular area, and V region of the…

Differential Diagnosis in Dermatopathology

Discussions

Tuberculoid leprosy and sarcoidosis are granulomatous dermatitides that resemble one another histopathologically because both consist of aggregations of epithelioid histiocytes in the dermis and, sometimes, in the subcutaneous fat. Despite the simil…

Differential Diagnosis in Dermatopathology

Discussions

Few subjects are as baffling and frustrating to dermatopathologists than the alopecias. Those aberrations are rivaled in difficulty only by diseases of nail units. Why do those subjects prove to be so recondite? Because biopsies of alopecias and dis…

Differential Diagnosis in Dermatopathology

Tuberculoid leprosy vs. Sarcoidosis

An inflammatory process that results from the effects of a drug administered systemically, e.g., by ingestion, inhalation, injection, or application rectally, and manifested usually by lesions distributed widely and symmetrically. Any of the many ex…

Differential Diagnosis in Dermatopathology

Trichotillomania (developed fully) vs. Traction alopecia (end stage)

An inflammatory process that results from the effects of a drug administered systemically, e.g., by ingestion, inhalation, injection, or application rectally, and manifested usually by lesions distributed widely and symmetrically. Any of the many ex…