There are conditions that take the title localized scleroderma but are not related to progressive systemic sclerosis. They are marked by areas of hardened skin, small or large, scattered or localized, single or multiple, and of variable shape. Here illustrated is morphea in the form of several discrete lesions of different shapes, all confined to the skin on the left side of the chest. The lesions are firm and atrophic.
This kind of morphea is highly characteristic. The solitary or individual lesion of the condition is a circle or oval of firm skin that is whitish, slightly depressed, and surrounded by a different color that is lilac or purple. There may be only one such lesion of moderate size or many of about the same size or very large ones covering large areas of skin. The course of the condition is variable too. Spontaneous recovery in children is common.
Illustrated is a type of morphea that is linear in shape and situated on the flexor aspect of a leg, extending from the medial aspect of the thigh through the popliteal space to near the Achilles tendon. Again the affected skin is hard, slightly depressed, and dyschromic. Extensive areas of linear morphea are the most difficult to treat. There is a tendency toward permanent deformity in the form of atrophy or contractures.
Here is another kind of hardened skin in the form of a depression, as though the result of a blow from a blunt instrument or a weapon like a saber. Location on one side of the brow is highly characteristic. Such lesions are seen with no other associated anomaly or as part of hemiatrophies. Atrophy or absence of subcutaneous fat is also part of such a process. Seizures may occur.
Illustrated here are lesions of morphea resolving. From an appearance like that in Fig. 17-2, the lesion has become brown although there is still some central sclerosis noted (Fig. 17-5). Figure 17-6 shows a lesion that is now reddish-brown that has risen to the level of the surrounding skin and will eventually nearly completely resolve or leave minor dyschromia. The cause of circumscribed scleroderma of any form is unknown.
Sometimes morphea can be more extensive and involve large areas of the integument. The lesions tend to be of plaque-type, beginning with erythematous to violaceous plaques that become sclerotic ...