Differential Diagnosis in Dermatopathology

Acne vulgaris, erythematous papule vs. Rosacea, erythematous papule

An inflammatory process in which lesions present themselves clinically as red macules and subtle scaly papules. They soon become so confluent that there is widespread redness and scaling punctuated by islands of skin that ostensibly are spared and b…

Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Follicular Occlusion Triad?

“The follicular occlusion triad: (acne conglobata, hidradenitis suppurativa, and dissecting cellulitis of the scalp). These diseases comprise a generic group. Though not usually classified together, there is reason to believe that they are…

Differential Diagnosis in Dermatopathology

Discussions

Erythematous papules of acne vulgaris and of rosacea have in common localization mostly to the face, suppurative infundibulitis, and a mixed infiltrate of inflammatory cells in the dermis, it containing lymphocytes and plasma cells, and sometimes hi…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

…open to a short tubule that serves as both sebaceous duct and infundibulum 6. Sebaceous ducts open into one or several widely dilated infundibula 6. Sebaceous ducts enter a single infundibulum-like structure, often without a distinct intervening s…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

Images 10.5.1A: Perivascular and interstitial dermatitis + 10.5.1B: Lymphocytes and eosinophils around venules, and neutrophils in the interstitium in conjunction with degeneration of bundles of collagen focally = Response to an arthropod…

Histologic Diagnosis of Inflammatory Skin Diseases

Infundibulitis secondary to agents topical

Infundibulitis secondary to agents topical Comment Noninfectious infundibulitides can be divided roughly into those of cause internal and those of cause external. Examples of internal causes of suppurative infundibulitis are drugs of different kinds…

Histologic Diagnosis of Inflammatory Skin Diseases

Majocchi’s granuloma

Majocchi’s granuloma Synonyms Nodular granulomatous perifolliculitis Tinea der unterschenkel Perifollicular granuloma Trichophytic granuloma Comment The term “Majocchi’s granuloma” is misleading because it implies that the…

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 10.39.1A: Infundibulitis, spongiotic, and peri-infundibulitis + 10.39.1B: Predominance of lymphocytes in and around infundibula dilated by corneocytes = Fox-Fordyce disease Spongiosis in the wall of an infundibulum near the site wh…

Histologic Diagnosis of Inflammatory Skin Diseases

Granuloma faciale

Granuloma faciale Presentation stereotypical Age and sex Adults of both sexes Distribution of lesions Localized to the face Shape of lesions Round or oval usually Individual lesions Papules, plaques, nodules, or tumors marked on their surface often…