Clinicohistopathological correlations in juvenile localized scleroderma: Studies on a subset of children with hypopigmented juvenile localized scleroderma due to loss of epidermal melanocytes

Background. Localized scleroderma or morphea is a connective tissue disorder characterized by fibrosis of the skin and subcutaneous tissue. Excessive accumulation of collagen underlies the fibrosis, yet the pathogenesis is unknown. A subset of localized scleroderma/morphea, juvenile localized scleroderma (JLS), affects children and adolescents. Objectives: The clinical and microscopic features of JLS have not been fully characterized. The goal is to better characterize the microscopic features of JLS. Methods: We collected a distinctive data set of 35 children with JLS, 19 (54%) of whom presented with hypopigmented lesions, and performed a retrospective chart and pathology review. We had adequate tissue for immunostaining studies on 8 of these individuals. Results: We found that: (1) CD34 and factor XIIIa immunostaining, reported previously in adult morphea and scleroderma, when used with clinical information, is valuable for confirming a diagnosis of JLS; and (2) presence of hypopigmented lesions in JLS correlates with immunostaining studies. Decreased numbers of MelanA(+) melanocytes were present at the dermoepidermal junction in lesional skin in two of 3 children with hypopigmented JLS and in two of 4 children with nonhypopigmented JLS. Limitations: The number of cases is small, a function of the small number of children who have biopsy specimens with material sufficient for multiple immunostaining procedures. Conclusions: These results provide a useful immunostaining method for confirmation of the diagnosis of JLS. They suggest a complex autoimmune phenotype in some children with JLS. (J Am Acad Dermatol 2011;65:364-73.)