Resolving Quandaries in Dermatology, Pathology & Dermatopathology

Follicular Occlusion Triad?

…are not follicles, but components of epidermis. Beneath each infundibulum and in continuity with it, resides a follicle that consists of an isthmus, stem, and bulb, in descending order. Except for anatomic site, acne conglobata, dissecting celluliti…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…orneocytes = Fox-Fordyce disease Spongiosis in the wall of an infundibulum near the site where an apocrine duct enters that part of the epidermis is typical of Fox-Fordyce disease. The abnormality basic, however, seems to be one of aberrant cornifica…

Histologic Diagnosis of Inflammatory Skin Diseases

Mycosis fungoides

…hat phenomenon pertained solely to surface epidermis. But the infundibulum is just as much epidermis as is surface epidermis, the two having the very same appearance histopathologic; that being the case, it should come as no surprise that that funnel…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…tosis is virtually specific for pityriasis rubra pilaris. The infundibulum is dilated by a plug of ortho- and parakeratotic cells. Unlike the situation in psoriasis, the granular zone in pityriasis rubra pilaris is preserved and mounds of parakeratos…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…in the dermis, also as “flame figures” and in an infundibulum + 10.5.38C + 10.5.38D = Response to an arthropod assault The 6-month-old boy from whom this specimen came had “unquestionable insect “bites” tha…

Histologic Diagnosis of Inflammatory Skin Diseases

Infundibulitis secondary to agents topical

…mmatory process usually expresses itself as suppuration in an infundibulum. What distinguishes some suppurative infundibulitides induced by agents topical from suppurative infundibulitides brought about by other types of factors noninfectious is the…

Histologic Diagnosis of Inflammatory Skin Diseases

Foreign body reaction

…, cornified cells, bacteria, yeast, and mites from a ruptured infundibulum, but many times their efforts are in vain; silica, suture, material of tattoos, urates, and splinters resist their best try, no matter how resolute. Corneocytes from ruptured…

Differential Diagnosis in Dermatopathology

Acne vulgaris, erythematous papule vs. Rosacea, erythematous papule

A hyperplasia of infundibular epithelium consequent to the effects of infection by a pox virus and manifesting itself clinically as one or more skin-colored, smooth-surfaced, dome-shaped papules, each with a central umbilication filled with horny ma…