Differential Diagnosis in Dermatopathology

Allergic contact dermatitis vs. Irritant contact dermatitis

Papules on skin and mucous membranes that result from infection of keratinocytes by different types of papillomavirus and classified according to their silhouettes, to wit, papillated (verrucae vulgares on different sites such as volar skin, i.e., v…

Differential Diagnosis in Dermatopathology

Differential Diagnosis

Dilated pore Pilar sheath acanthoma 1. An infundibular cyst fundamentally 1. A neoplasm with follicular and sebaceous differentiation fundamentally 2. Step sections reveal an infundibular cyst and, often, signs of rupture of it 2. Step section…

Differential Diagnosis in Dermatopathology

Discussions

Alopecia areata and trichotillomania have several attributes histopathologic in common, namely, some follicles in catagen and often in telogen, long fibrous tracks behind shortened follicles and, in sections from some specimens, and hardly any periv…

Differential Diagnosis in Dermatopathology

Discussions

The alopecias of discoid lupus erythematosus and of lichen planus share several findings histopathologic, among them being perivascular, peri-infundibular, and perifollicular infiltrates of lymphocytes, vacuolar alteration at the junction between in…

Differential Diagnosis in Dermatopathology

Discussions

Discoid lupus erythematosus and dermatomyositis have more findings histopathologic in common than they have differences. Both diseases are characterized by compact orthokeratosis, an epidermis thinned focally, a pattern of rete ridges and dermal pap…

Differential Diagnosis in Dermatopathology

Discussions

Ichthyosis vulgaris and X-linked ichthyosis are true ichthyoses in the sense that the clinical appearance of their scales resembles vaguely those of fish (In Greek, ichthos means fish, and -osis means a condition of). As in all ichthyoses, the scale…

Differential Diagnosis in Dermatopathology

Lichen simplex chronicus vs. Hypertrophic lichen planus

Papules on skin and mucous membranes that result from infection of keratinocytes by different types of papillomavirus and classified according to their silhouettes, to wit, papillated (verrucae vulgares on different sites such as volar skin, i.e., v…

Differential Diagnosis in Dermatopathology

Lichen amyloidosis vs. Colloid milium

Papules on skin and mucous membranes that result from infection of keratinocytes by different types of papillomavirus and classified according to their silhouettes, to wit, papillated (verrucae vulgares on different sites such as volar skin, i.e., v…

Differential Diagnosis in Dermatopathology

Epidermolytic hyperkeratosis vs. Plane wart

Papules on skin and mucous membranes that result from infection of keratinocytes by different types of papillomavirus and classified according to their silhouettes, to wit, papillated (verrucae vulgares on different sites such as volar skin, i.e., v…

Differential Diagnosis in Dermatopathology

Nevus verrucosus vs. Acanthosis nigricans

Papules on skin and mucous membranes that result from infection of keratinocytes by different types of papillomavirus and classified according to their silhouettes, to wit, papillated (verrucae vulgares on different sites such as volar skin, i.e., v…