Background: Stiff skin syndrome (SSS) is a rare disease characterized by sclerosis of the skin. Cases of both widespread and segmental SSS have been reported.
Objectives: To report the clinical and histopathological characteristics of a large series of SSS.
Materials & methods: We retrospectively analysed the clinical and histopathological characteristics of widespread and segmental SSS collected from a dermatology department. We also compared histopathology between segmental SSS and morphea.
Results: Thirty-one cases, including three widespread SSS and 28 segmental SSS, were collected. Skin lesions of widespread SSS generally showed skin sclerosis concentrating over the lumbar, buttocks, thighs, proximal part of limbs, and shoulders with specific abnormal gait and posture. Skin lesions of segmental SSS generally showed sclerotic plaques involving the thigh, lumbar area and buttocks, associated with hypertrichosis, hyperpigmentation and a cobblestone appearance. Segmental SSS did not typically cause joint limitation or serious physical discomfort. Histopathologically, SSS showed proliferation of fibroblasts and sclerosis of collagen in the dermis or subcutaneous tissue. Compared with morphea, SSS showed more prominent proliferation of fibroblasts and completely lacked lymphocyte infiltration.
Conclusion: Segmental SSS represents the major variant of SSS. Histopathologically, SSS shows proliferation of fibroblasts, sclerosis and an absence of inflammation.
Keywords: fibroblast; joint mobility; morphea; segmental stiff skin syndrome; stiff skin syndrome; widespread stiff skin syndrome.