Differential Diagnosis at Particular Sites Discoid Lupus Erythematosus of the Scalp

DLE of the scalp (Fig. 11.2A) typically arises as one or a few roundish erythematous plaques identical to DLE lesions elsewhere on the skin. When atrophy develops, they gradually transform into patches of scarring alopecia that may be surrounded by rims of scaly erythema. In the early phase, it must be distinguished from psoriasis and seborrheic dermatitis (see previously herein). In advanced stages, DLE may

Scutula Favus
Fig. 11.2. A Atrophic alopecia in discoid lupus erythematosus. Note the widened erythematous follicular openings between flattened atrophic areas. B Lichen ruber planopilaris: confluent small areas of atrophic skin with interspersed unaffected hair-bearing follicles

resemble all other instances of scarring alopecia. One important mark is that DLE of the scalp is often accompanied by analogous lesions of the face.

Lichen planopilaris (Fig. 11.2B) of the scalp is characterized by very small (2-3 mm) hairless atrophic areas that, by partial confluence, may occupy larger areas, particularly in the central scalp regions, a distribution pattern reminiscent of lichen planus lesions of the skin. The atrophic areas are smooth, devoid of follicular orifices, and skin colored (because the inflammatory infiltrate is not located at the interfol-licular epidermis but around the hair follicles) but may display a subtle violaceous hue at the periphery. Characteristically, tufts of normal hairs emerge from between the alopecic areas, resulting in an irregular, "moth-eaten" appearance.

Linear morphea (coup de sabre) is an easy clinical diagnosis. It is characterized by a single linear paramedian band of depressed sclerodermatous skin that adheres to the deep fascia and even the bone. Erythema and scaling is usually absent, and hair loss develops as a late event.

Folliculitis decalvans, which in its active stages can hardly be confused with DLE because of its pustules and crusts, eventually leads to cicatricial alopecia, which is morphologically similar to that of lichen planopilaris (small areas of alopecia intermingled with tufts of normal hair, most often in the parietal and occipital areas). Similar hairless scars, although less extensive, may arise from furuncles and trichophytic infections (Kerion Celsi type).

Noninflammatory and epidemic types of tinea capitis (microsporia) begin with small erythemas or erythematous papules around hair follicles that subsequently spread centrifugally like DLE lesions of the scalp. In contrast to DLE, these lesions tend to be multiple, show little inflammation at early stages, and occur almost exclusively in children. Typically, hairs do not fall out but break close to the skin surface, and residual scarring is minimal. In contrast, scarring is pronounced in the favus type of tinea capitis. This rare type of mycosis can be distinguished from DLE by its typical focal crusting and scaling ("scutula").

100 Hair Growth Tips

100 Hair Growth Tips

100 Hair Growth Tips EVERY Balding Person Should Know. This Report

Get My Free Ebook


Post a comment