The pathogenesis of systemic sclerosis.

Department of Medicine, University of California, San Francisco, 94143, USA.
Annual Review of Pathology Mechanisms of Disease (Impact Factor: 22.13). 02/2011; 6:509-37. DOI: 10.1146/annurev-pathol-011110-130312
Source: PubMed

ABSTRACT Systemic sclerosis (SSc), also known as scleroderma, is a rare connective tissue disease characterized by vascular and immune dysfunction, leading to fibrosis that can damage multiple organs. Its pathogenesis is complex and poorly understood. Two major clinical subtypes are the limited and diffuse forms. Research into SSc has been hampered by its rarity, its clinical heterogeneity, and the lack of mouse models that accurately recapitulate the disease. Clinical and basic studies have yielded some mechanistic clues regarding pathogenesis. Recent insights gained through the use of microarrays have revealed distinctive subsets of SSc within and beyond the limited and diffuse subsets. In this review, we discuss potential mechanisms underlying the vascular, autoimmune, and fibrotic points of dysregulation. Proper categorization of SSc patients for research studies by use of microarrays or other biomarkers is critical, as disease heterogeneity may explain some of the inconsistencies of prior studies.

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    ABSTRACT: En coup de sabre (linear scleroderma of face) is a rare type of morphea (localized scleroderma) involving frontoparietal area of the forehead and scalp. Many triggering factors have been implicated in the development of morphea like trauma, immobilization, bacille Calmette–Guérin (BCG) vaccination, injections of vitamin K, mechanical compression from clothing, etc. Linear scleroderma primarily affects the pediatric population, with 67% of patients diagnosed before 18 years of age. In this article, we describe a case of 26 year old female who presented with a three months history of brownish indurated plaque of skin on the frontal and forehead regions of the head. The patient gave a history of trauma at the same site six years back. The diagnosis of morphea was made clinically supported by histopathological features of the skin biopsy. Her neurological examination was normal. ANA was negative. Brain MRI didn’t reveal any abnormality. She was treated with topical tacrolimus 0.1% ointment. The late onset en coup de sabre is a rare presentation and hence reported.
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    ABSTRACT: Scleroderma is a rare connective tissue disease that is manifested by cutaneous sclerosis and variable systemic involvement. Two categories of scleroderma are known: systemic sclerosis, characterized by cutaneous sclerosis and visceral involvement, and localized scleroderma or morphea which classically presents benign and self-limited evolution and is confined to the skin and/or underlying tissues. Localized scleroderma is a rare disease of unknown etiology. Recent studies show that the localized form may affect internal organs and have variable morbidity. Treatment should be started very early, before complications occur due to the high morbidity of localized scleroderma. In this review, we report the most important aspects and particularities in the treatment of patients diagnosed with localized scleroderma.
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    ABSTRACT: Systemic sclerosis (SSc) is a rare systemic autoimmune disease characterized by skin and organ fibrosis. The pathogenesis of SSc and its progression are poorly understood. The SSc intrinsic gene expression subsets (inflammatory, fibroproliferative, normal-like, and limited) are observed in multiple clinical cohorts of patients with SSc. Analysis of longitudinal skin biopsies suggests that a patient's subset assignment is stable over 6-12 months. Genetically, SSc is multi-factorial with many genetic risk loci for SSc generally and for specific clinical manifestations. Here we identify the genes consistently associated with the intrinsic subsets across three independent cohorts, show the relationship between these genes using a gene-gene interaction network, and place the genetic risk loci in the context of the intrinsic subsets. To identify gene expression modules common to three independent datasets from three different clinical centers, we developed a consensus clustering procedure based on mutual information of partitions, an information theory concept, and performed a meta-analysis of these genome-wide gene expression datasets. We created a gene-gene interaction network of the conserved molecular features across the intrinsic subsets and analyzed their connections with SSc-associated genetic polymorphisms. The network is composed of distinct, but interconnected, components related to interferon activation, M2 macrophages, adaptive immunity, extracellular matrix remodeling, and cell proliferation. The network shows extensive connections between the inflammatory- and fibroproliferative-specific genes. The network also shows connections between these subset-specific genes and 30 SSc-associated polymorphic genes including STAT4, BLK, IRF7, NOTCH4, PLAUR, CSK, IRAK1, and several human leukocyte antigen (HLA) genes. Our analyses suggest that the gene expression changes underlying the SSc subsets may be long-lived, but mechanistically interconnected and related to a patients underlying genetic risk.
    PLoS Computational Biology 01/2015; 11(1):e1004005. DOI:10.1371/journal.pcbi.1004005 · 4.83 Impact Factor