Histologic Diagnosis of Inflammatory Skin Diseases

Identification of Basic Patterns: Subcutaneous Fat: Panniculitis

See Fig. 5.385 A-C. Figure 5.385 Patterns of panniculitis. A. Septal mostly. B. Lobular mostly. C. Septal and lobular “equally.” At scanning magnification, the normal subcutaneous fat is seen to be segregated by struts of fibrous tiss…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.38.1A: Pustular dermatitis, infundibular + 10.38.1B: A hair containing hyphae in an abscess = Suppurative infundibulitis of dermatophytic cause (Majocchi’s granuloma) The hair was spewed into the dermis when an infundibul…

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

a-1 antitrypsin deficiency

α-1 antitrypsin deficiency Presentation stereotypical Age and sex Any age, predominantly women Distribution of lesions Particularly on the trunk and extremities Configuration of lesions Shapes of subcutaneous nodules bizarre, ulceration with dischar…

Histologic Diagnosis of Inflammatory Skin Diseases

Errors and Reasons

…at NYU. Error: “Suppurative folliculitis” truly is suppuration in a follicle. Reason: What is termed “suppurative folliculitis” really is suppuration in infundibular epidermis, i.e., suppurative “infundibulitis.” E…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…, and panniculitis, septal and lobular + 10.15.7B: Foci of suppuration surrounded by histiocytes, some of them multinucleate, arranged in a palisade = Crohn’s disease Palisaded granulomas around a prominent focus of suppuration in the lower…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.35.1A: Nodular dermatitis, granulomatous and suppurative + 10.35.1B: Countless neutrophils in the interstitium + 10.35.1C + 10.35.1D = Factitious dermatitis Each focus of fibrin represents a site where a needle pene…

Histologic Diagnosis of Inflammatory Skin Diseases

Foreign body reaction

Foreign body reaction Synonyms Foreign body granuloma Presentation stereotypical Age and sex Any age and either sex Distribution of lesions Localized usually Individual lesions Papules, plaques, and nodules Course Longstanding Variations clinical…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.73.1A: Panniculitis, lobular + 10.73.1B: Extensive granular fat necrosis with suppuration contiguous with it = Pancreatic panniculitis, early  Lipases released into the blood stream from a diseased pancreas induced the changes s…