Abstract and Introduction
Abstract
Systemic sclerosis (SSc) is a clinically heterogeneous, systemic disorder affecting connective tissue of skin, internal organs, and walls of blood vessels. It is characterized by alterations of the microvasculature in the form of hypoxia, digital ulcers, and pulmonary arterial hypertension; disturbances of the immune system, including dysbalance of cytokine expression, autoantibodies (Auto-ab), and abnormalities of blood progenitor and/or effector cells; and by massive deposition of collagen in the connective tissue of the skin and various internal organs. This review discusses epidemiology and survival; clinical features including subsets and internal organ involvement; pathophysiology including genetics, microvasculature, immunobiology, fibroblasts (FBs), and connective tissue metabolism; and environmental factors. Early diagnosis and individually tailored therapy help to manage this disorder. Therapy involves immunomodulation and targeting of blood vessels and fibrosis. The multicenter online database "European Scleroderma Trials and Research" project allows further insight of prognostic factors and conception of new therapies. Physical and psychotherapy are important.
Introduction
Systemic sclerosis (SSc) is a clinically heterogeneous generalized disorder affecting the connective tissue of the skin, blood vessel wall, and internal organs such as the gastro-intestinal tract, lungs, heart, and kidneys. It is characterized by alterations of the microvasculature, disturbances of the immune system, and by massive deposition of collagen in the connective tissue. The spectrum of sclerodermatous diseases comprises a wide variety of clinical entities such as morphea (patchy, linear, generalized), pseudo-scleroderma, and the overlap-syndromes with similar cutaneous and histopathologic manifestations as compared to SSc. Skin tightening, contractures, calcification, and ulcers frequently lead to functional impairment and changes in appearance.
Due to the complexity of the internal organ involvement, SSc has attracted attention from many disciplines, including rheumatology, pulmonology, cardiology, nephrology,gastroenterology, and dermatology. Many aspects of diagnosis and therapy require close cooperation between several disciplines. In addition, the complex pathophysiology of SSc, involving genetic factors, environmental influences, vascular and immune system functions, as well as FBs and matrix substances, makes SSc attractive to study the pathophysiology of autoimmune connective tissue disorders. Basic functions of various cell types (endothelial cells [EC], T lymphocytes, monocytes, FB, mast cells) as well as the production and effects of cytokines, growth factors, and adhesion molecules have been studied. In addition, animal models have been developed to give closer insights into the pathophysiology of this disease.
Lab Med. 2011;42(9):562-572. © 2011 American Society for Clinical Pathology
Comments