Chapter 055. Immunologically Mediated Skin Diseases (Part 10)

Scleroderma often eventuates in development of an expressionless, masklike facies.Morphea is characterized by localized thickening and sclerosis of skin, usually affecting young adults or children. Morphea begins as erythematous or flesh-colored plaques that become sclerotic, develop central hypopigmentation, and demonstrate an erythematous border. In most cases, patients have one or a few lesions, and the disease is termed localized morphea. In some patients, widespread cutaneous lesions may occur, without systemic involvement. This form is called generalized morphea. Most patients with morphea do not have autoantibodies.Skin biopsy of morphea is indistinguishable from that of scleroderma. Linear scleroderma is a limited...
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Chapter 055. Immunologically Mediated Skin Diseases (Part 10) Chapter 055. Immunologically Mediated Skin Diseases (Part 10) Scleroderma often eventuates in development of an expressionless, mask-like facies. Morphea is characterized by localized thickening and sclerosis of skin,usually affecting young adults or children. Morphea begins as erythematous orflesh-colored plaques that become sclerotic, develop central hypopigmentation,and demonstrate an erythematous border. In most cases, patients have one or a fewlesions, and the disease is termed localized morphea. In some patients, widespreadcutaneous lesions may occur, without systemic involvement. This form is calledgeneralized morphea. Most patients with morphea do not have autoantibodies.Skin biopsy of morphea is indistinguishable from that of scleroderma. Linearscleroderma is a limited form of disease that presents in a linear, bandlikedistribution and tends to involve deep as well as superficial layers of skin.Scleroderma and morphea are usually quite resistant to therapy. For this reason,physical therapy to prevent joint contractures and to maintain function isemployed and is often helpful. Diffuse fasciitis with eosinophilia is a clinical entity that can sometimes beconfused with scleroderma. There is usually the sudden onset of swelling,induration, and erythema of the extremities frequently following significantphysical exertion. The proximal portions of extremities (arms, forearms, thighs,legs) are more often involved than are the hands and feet. While the skin isindurated, it is usually not bound down as in scleroderma; contractures may occurearly secondary to fascial involvement. The latter may also cause muscle groups tobe separated and veins to appear depressed. These skin findings are accompaniedby peripheral blood eosinophilia, increased erythrocyte sedimentation rate, andsometimes hypergammaglobulinemia. Deep biopsy of affected areas of skinreveals inflammation and thickening of the deep fascia overlying muscle. Aninflammatory infiltrate composed of eosinophils and mononuclear cells is usuallyfound. Patients with eosinophilic fasciitis appear to be at increased risk to developbone marrow failure or other hematologic abnormalities. While the ultimatecourse of eosinophilic fasciitis is uncertain, many patients respond favorably totreatment with prednisone in doses ranging from 40–60 mg/d. The eosinophilia-myalgia syndrome, a disorder reported in epidemicnumbers in 1989 and linked to ingestion of L-tryptophan manufactured by a singlecompany in Japan, is a multisystem disorder characterized by debilitatingmyalgias and absolute eosinophilia in association with varying combinations ofarthralgias, pulmonary symptoms, and peripheral edema. In a later phase (i.e., 3–6months after initial symptoms), these patients often develop localizedsclerodermatous skin changes, weight loss, and/or neuropathy (Chap. 316). Theprecise cause of this syndrome, which may resemble other sclerotic skinconditions, is unknown. However, the implicated lots of L-tryptophan containedthe contaminant 1,1-ethylidene bis[tryptophan]. This contaminant may bepathogenic or a marker for another substance that provokes the disorder. Further Readings Anhalt GJ: Paraneoplastic pemphigus. J Investig Dermatol Symp Proc 9:29,2004 [PMID: 14870982] Braverman IM: Connective tissue diseases, in Skin Signs of SystemicDisease, 3d ed. Philadelphia, Saunders, 1998 Mutasim DF et al: Immunobullous diseases. J Am Acad Dermatol 52:1029,2005 [PMID: 15928622] Payne AS et al: Desmosomes and disease: Pemphigus and bullousimpetigo. Curr Opin Cell Biol 16:536, 2004 [PMID: 15363804] Schmidt E, Zillikens D: Autoimmune and inherited subepidermal blisteringdiseases: Advances in the clinic and the laboratory. Adv Dermatol 16:113, 2000[PMID: 11094626] Sontheimer RD: Skin manifestations of systemic autoimmune connectivetissue disease: Diagnostics and therapeutics. Best Pract Res Clin Rheumatol18:429, 2004 [PMID: 15158749] Udey MC, Stanley JR: Pemphigus—diseases of antidesmosomalautoimmunity. JAMA 282:572, 1999 [PMID: 10450720] Yancey KB, Egan CA: Pemphigoid: Clinical, histologic,immunopathologic, and therapeutic considerations. JAMA 284:350, 2000 [PMID:10891967]