Dermatology Practical & Conceptual

Widespread pruritic papules on the trunk and extremities

The patient A 42-year-old Caucasian man presented with a 15-year history of a widespread, persistent, pruritic eruption over his trunk and extremities. He was not on medication and had no relevant family history. On physical examination, multiple di…

Histologic Diagnosis of Inflammatory Skin Diseases

Sweet’s syndrome

Sweet’s syndrome Synonyms Acute febrile neutrophilic dermatosis Presentation stereotypical Age and sex Middle-aged persons, more often women than men Distribution of lesions Upper and lower extremities, neck, and face. Sometimes limited to dor…

Histologic Diagnosis of Inflammatory Skin Diseases

Pityriasis rosea

Pityriasis rosea Synonyms Pityriasis circiné Pityriasis disseminé Pityriasis marginée et circiné Roseola annulata Roseola squamosa Presentation stereotypical Age and sex Usually young to middle-aged persons of both sexes; women especially Distributi…

Differential Diagnosis in Dermatopathology

Xanthogranuloma vs. Reticulohistiocytic granuloma

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…

Histologic Diagnosis of Inflammatory Skin Diseases

Crohn’s disease

Crohn’s disease Synonyms Inflammatory bowel disease Regional ileitis Regional enteritis Chronic cicatrizing enteritis Presentation stereotypical Age and sex Young adults; slight predominance of women Distribution of lesions The poles of the ga…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

Urticaria Urticarial lesions of bullous pemphigoid 1. Infiltrate of inflammatory cells usually sparse 1. Infiltrate of inflammatory cells usually moderately dense 2. Infiltration of inflammatory cells spares the papillary dermis and the epider…

Histologic Diagnosis of Inflammatory Skin Diseases

Blister secondary to hypoxemia and local pressure

Blister secondary to hypoxemia and local pressure Presentation stereotypical Age and sex Any age and either sex Distribution of lesions Sites of pressure Configuration of lesions Linear often, especially over wings of scapulae Individual lesions Ery…

Histologic Diagnosis of Inflammatory Skin Diseases

Degos’ disease (malignant atrophic papulosis)

Degos’ disease (malignant atrophic papulosis) Synonyms Degos’ syndrome Malignant atrophic papulosis Papulosis atrophicans maligna Koehlmeier-Degos syndrome Thromboangiitis cutaneointestinalis disseminata Fatal cutaneointestinal syndrome…