ISSN:1040-8711    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

HLA-B27is a serologic specificity that encompasses 20 different alleles—HLA-B*2701toB*2720. These alleles are also called subtypes ofHLA-B27, and they have evolved from theB*2705subtype, mostly from changes in exons 2 and 3 (which encode the alpha 1 and alpha 2 domains of the peptide binding groove, respectively). Occurrence of ankylosing spondylitis (AS) or related spondyloarthropathy (SpA) has thus far been documented in subjects possessing any one of the first 10 subtypes. However,B*2706in Southeast Asian andB*2709in the Italian island population of Sardinia may have a relatively much weaker association with AS. The 10 most recent subtypes have not yet been studied for disease association. There may exist a hierarchical ranking, resulting, in part, from differences in other co-inherited genetic factors, or due to environmental factors;eg,B*2705is clearly disease-associated throughout the world, but not among the West Africans of Senegal and Gambia. It is important to investigate whether certain subtypes show any preferential association with some of the clinical features or forms of AS and related SpA among the various ethnic/racial populations and geographic regions of the world. This may help to identify the polymorphic positions ofHLA-B27that may have a disease-predisposing role.

ISSN:1040-8711    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

The Spondylitis Association of America has been the driving force behind a major research initiative in the US, having leveraged a substantial amount of money into a $4.5 million grant from the National Institute of Arthritis and Musculoskeletal and Skin Diseases. The grant last year established the North American Spondylitis Consortium to expedite the search for genes that determine susceptibility to ankylosing spondylitis. The German Ankylosing Spondylitis Society, which has more than 14,000 patient members, initiated in 1996 a professional survey of ankylosing spondylitis patients, with financial support from the German Federal Health Ministry. The results of this survey have recently been published, but only in the German language; a part of it is summarized here in English. Following are some of the important findings. The average age at disease onset does not differ significantly between men and women, but there is a significantly longer delay in disease diagnosis among female patients. The average delay in disease diagnosis is getting shorter; there was an average delay of 15 years for patients with disease onset in the 1950s, and it decreased to 7.5 years for patients with disease onset between 1975 and 1979. There was a relatively greater degree of underdiagnosis of the disease among female than male patients in the past; whereas only 10% of the patients in whom the disease was diagnosed in about 1960 were women, this percentage has progressively increased in the subsequent decades to reach 46% among those in whom the disease was diagnosed since 1990. The speed at which spinal ankylosis progresses is slower in female patients, but women are in a significantly worse situation than men in terms of pain and the need for drug therapy, even though the women in the German Ankylosing Spondylitis Society sample are, on average, younger than the men and have a shorter average disease duration. It is possible that the slower and relatively incomplete progression to spinal ankylosis in female patients impedes the occurrence of a decrease in pain with time, compared with that observed in male patients.

ISSN:1040-8711    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

The arthritogenic peptide hypothesis has inspired research aimed at defining the peptide-presenting properties ofHLA-B27subtypes and their relation to ankylosing spondylitis. Various studies have shed new light on the influence ofHLA-B27polymorphism in modulating peptide binding and T-cell antigen presentation. Moreover, multiple factors along the antigen processing-loading pathway, including tapasin, contribute to shaping theHLA-B27repertoire. Other studies have revealed significant peptide-binding similarities betweenHLA-B27and subtypes ofHLA-B39, supporting a role of this antigen in spondyloarthropathy. A putative pathogenetic role of theHLA-B27heavy chain, initially suggested from studies in transgenic mice, is claimed on the basis of novel, yet circumstantial, evidence concerning an apparently unusual capacity of the heavy chain to form stable homodimers or misfold after biosynthesis. Finally, it appears that arthritogenic infections might downregulateHLA-B27expression, favoring bacterial survival. The specificity and mechanism of this phenomenon are yet to be defined.

ISSN:1040-8711    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

An inflammatory arthritis is known to follow urogenital infection with the intracellular bacteriumChlamydia trachomatisin some individuals, and recent research results have elucidated important aspects of the characteristics of thisChlamydia-associated joint disease. Although the several extra-articular features ofChlamydia-induced arthritis have been defined clinically, their detailed causes remain largely unexplained. Current data indicate that the clinical characteristics of joint disease associated withC. trachomatisinfection and those associated with postenteric arthritis are not easily distinguishable, although the response of each to antibiotic therapy does differ. The biologic characteristics ofChlamydiaand enteric organisms in the joint show profound differences, and these are probably responsible for the variable responses to drug treatment. Molecular analyses of synovialC. trachomatishave demonstrated that long-term infection of the joint occurs primarily in synovial tissue and that the organism exhibits highly unusual biologic properties in its synovial context. These unusual molecular, biochemical, and other characteristics provide explanations for the frequent culture negativity of joint materials forC. trachomatisand for several other aspects of the arthritogenic process. Much remains to be learned concerning the behavior of this organism in the joint and concerning its interaction with its synovial host cells.

ISSN:1040-8711    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

The cause of ankylosing spondylitis remains unclear. Proof that this disorder is an autoimmune disease attributable to cross-reactivity between bacteria andHLA-B27is still lacking. Differences in endogenous peptide presentation byHLA-B27subtypes might be relevant in the etiopathogenesis. Fractures of the osteoporotic spine contribute to morbidity. Spinal cord injury may occur. MR imaging enables identifying sacroiliitis earlier than plain radiography. Sweet syndrome has now been described in patients with ankylosing spondylitis and Crohn disease. Progress has been made in the assessment of ankylosing spondylitis. There are now core sets for different settings and validated instruments for functioning and disease activity that will enable demonstrating efficacy of new therapeutic interventions.The debate continues on classification of postinfectious and reactive arthritis. Bacterial antigens may be found in the inflamed joints; occasionally 16S ribosomal RNA is also demonstrated. Antibiotics seem not to be effective in postenteric reactive arthritis.More than 25 years have now elapsed since the association between ankylosing spondylitis andHLA-B27was first described in 1973. The cause of this disease is still unknown, but a lot of progress has been made regarding the molecular structure ofHLA-B27, the spectrum of disease, the clinical and radiographic assessment of ankylosing spondylitis, and its treatment. Recent advances in research on ankylosing spondylitis are reviewed here.

ISSN:1040-8711    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

This paper reviews the recent literature on the juvenile spondyloarthropathies. Several case reports emphasized clinical characteristics of the spondlyoarthropathies including reactive arthritis. MR imaging seemed to enhance the detection of sacroiliitis in children with spondyloarthropathies. The presence of different cytokines in various forms of juvenile arthritis including the juvenile spondyloarthropathies was investigated and suggested a role for the anti-inflammatory cytokines in milder disease. Evidence for the association of low-molecular-weight polypeptide gene polymorphism with susceptibility to acute anterior uveitis was found in a Mexican population of patients with spondyloarthropathies, including 80 with juvenile spondyloarthropathy. A review of therapeutic use of sulfasalazine in children with chronic arthritis, including those with juvenile spondyloarthropathy, concluded that it was safe and effective. Last, a study assessed aerobic fitness and physical activity in patients with juvenile spondyloarthropathy in remission and suggested a decline in physical fitness in older patients.

ISSN:1040-8711    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Articles included in this review reflect the recent advances made in basic research and the clinical management of psoriatic arthritis in 1999. Some of these advances are destined to modify the current approach to the disease. The problems related to nosology and epidemiology, the two still controversial aspects, are discussed first. Genetic susceptibility to psoriasis and psoriatic arthritis, and the inciting role played by some bacteria, are confirmed, and attention is focused on the role of T cells, cytokines, adhesion molecules, and angiogenetic factors in the skin and synovial membrane. New classification criteria are provided and a simplified spectrum of the disease seems to emerge from clinical studies. Modern imaging techniques enable early articular changes to be discovered, support innovative pathogenetic hypotheses, and allow new therapeutic approaches.

ISSN:1040-8711    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

HLA-B27is virtually absent in most of the sub-Saharan Africa populations, and ankylosing spondylitis is rare; only a few patients have been reported from central and southern Africa.HLA-B27was present in only one of 17 patients (6%). The disease shows clinical features that are similar to those observed in whiteHLA-B27-negative patients with ankylosing spondylitis;ie, the disease onset is later compared withHLA-B27-positive patients, the patients rarely get acute anterior uveitis as one of the extra-articular manifestations, and familial occurrence of ankylosing spondylitis is rarely observed. There is a virtual absence of ankylosing spondylitis even in the west African countries of Gambia and Senegal, where 3% to 6% of the general population hasHLA-B27. The epidemic of HIV infection in sub-Saharan Africa in recent years, however, has been associated with a dramatic upsurge in the prevalence of spondyloarthropathies other than ankylosing spondylitis, primarily reactive arthritis and undifferentiated forms of the disease, and less often psoriatic arthritis.HLA-B27, because of its rarity and virtual lack of association with the observed cases of spondyloarthropathy in this population, cannot be used as an aid to diagnosis of spondyloarthropathy in black Africans. Conversely, HIV infection is increasingly showing such a strong association with reactive arthritis, psoriatic arthritis, and undifferentiated spondyloarthropathies in sub-Saharan African populations that any patient with acute or chronic inflammatory arthritis may need to be tested for possible HIV infection. More research is needed on the evaluation of risk and protective factors in sub-Saharan African populations to better delineate the relative importance of genetic and environmental factors in the pathogenesis of spondyloarthropathies.

ISSN:1040-8711    

出版商:OVID    

年代:2000

数据来源: OVID

ISSN:1040-8711    

出版商:OVID    

年代:2000

数据来源: OVID