Scleroderma ‘en coup de sabre’ and progressive facial hemiatrophy. Is it possible to differentiate them?

The aim was to be able to evaluate the diagnosis of two diseases by a consensus of clinical opinion used in the Department of Dermatology of the National Institute of Paediatrics in Mexico City. To differentiate between scleroderma ‘en coup de sabre’ (SCS) and progressive facial hemiatrophy (PFH), colour slides of 13 patients diagnosed as SCS and nine as PFH were examined by two dermatologists and microscopic slides by two pathologists. In both cases, the slides were randomly presented and no clinical information was given. The clinical and histopathological findings were statistically compared with two-tailed tests and α = 0.05. κ coefficients were obtained to evaluate the concordance between dermatologists, pathologists, and in terms of the consensus diagnosis. The usefulness of photographic assessment is limited by the inability to palpate the consistency of lesions. The most important clinical feature that differentiated both conditions was cutaneous sclerosis present in eight of 13 patients with SCS and in none of the PFH patients (P < 0.005). Other clinical features more frequently found in SCS were cutaneous hyperpigmentation and alopecia. The more frequent clinical features in PFH were total hemifacial involvement and ocular changes. Statistically significant histopathological features were: connective tissue fibrosis present in all cases with SCS and two of nine patients with PFH (P < 0.0002); adnexal atrophy present in 11 of 13 patients with SCS, and in three of nine with PFH (P < 0.02), and mononuclear cell infiltrates in all patients with SCS cf. six with PFH (P < 0.05). Our results suggest that in most cases it is possible to differentiate SCS from PFH based on clinicopathological findings.