HLA-DQA1*0101 haplotypes and disease outcome in early onset pauciarticular juvenile rheumatoid arthritis.

To further investigate a clinical impression that patients with early onset pauciarticular juvenile rheumatoid arthritis (EOPA-JRA) who carry HLA-DQw1 have more severe arthritis, we subtyped HLA-DQw1 in American midwestern patients with EOPA-JRA. The HLA-DQA1*0101 subtype was present in 10 of 19 patients who developed persistent polyarticular erosive disease compared with 18 of 92 healthy controls (chi 2 = 9.13, p = 0.003, RR = 4.6), and occurred more frequently in this polyarticular group than in patients without polyarticular erosive disease (chi 2 = 4.11, p = 0.040, RR = 3.0). The presence of HLA-DQA1*0101 was significantly lower in patients with chronic iridocyclitis than in patients without chronic iridocyclitis (chi 2 = 7.07, p = 0.008, RR = 0.21). In HLA-DQA1*0101 positive patients, DNA sequences of the beta-1 domain of the HLA-DQ alpha and HLA-DQ beta genes (HLA-DQA1*0101, HLA-DQB1*0501 and HLA-DQB1*0503) were identical to those in controls. In this midwestern EOPA-JRA population, HLA-DQA1*0101 or genes in linkage disequilibrium with it, are associated with a cohort of patients with EOPA-JRA with distinct clinical characteristics.     

2007 annual research and education meeting of the Spondyloarthritis Research and Therapy Network (SPARTAN)

OBJECTIVE: The Spondyloarthritis Research and Therapy Network (SPARTAN; www.spartangroup.org) was founded in 2003 by a group of North American clinicians and researchers to promote research, education, and treatment of spondyloarthritis (SpA). In past years, it has produced and disseminated United States-specific modifications of the ASsessments in Ankylosing Spondylitis (ASAS) guidelines for the use of anti-tumor necrosis factor (TNF) therapy in AS1,2. SPARTAN held its fifth annual research meeting in September 2007 in Cleveland, Ohio. Highlights of the meeting included updates on current research in SpA, including epidemiology and genetics, bone formation and inflammation, biomarkers, activation of the IL-23/IL-17 axis, and animal models. A presentation was made on basic and clinical science of inflammatory bowel disease, and an educational pre-meeting conference was specifically designed for rheumatology fellows.     

HLA and cytokine gene polymorphisms in relation to occurrence of palindromic rheumatism and its progression to rheumatoid arthritis

OBJECTIVE: Palindromic rheumatism (PR) is an episodic arthropathy that may precede typical rheumatoid arthritis (RA), although pathogenetic relationships between these disorders remain unclear. The predictive value for those immunogenetic risk factors implicated in RA for disease progression in PR remains to be established. A previous retrospective analysis from our group has implicated rheumatoid factor in disease progression. Our objective was to determine the contribution of HLA and cytokine gene polymorphisms implicated in RA to predisposition to PR and to progression of PR to chronic joint inflammation. METHODS: We studied 147 patients with PR seen in a tertiary referral center; 87 were selected retrospectively from the period 1986-96 using a structured selection process and 60 were selected prospectively in the period 1997-2001. Comparison groups included 149 patients with RA and 149 ethnically matched controls. Typing for HLA-DRB1 alleles and HLA-DRB1-04 subtypes was performed following polymerase chain reaction (PCR) amplification using sequence-specific primers (SSP). Cytokine genotypes were ascertained following PCR-SSP with and without digestion with restriction enzymes. Time-adjusted survival analysis (Kaplan-Meier) and multivariate logistic regression were used to assess the independent contribution of immunogenetic markers in assessing progression of PR to chronic joint inflammation. RESULTS: Thirty-one percent of patients progressed to connective tissue disease after a mean of 10.6 (retrospective group) and 3.9 (prospective group) years. A significantly increased prevalence of the shared epitope (SE) allele was noted in patients with PR (65%) versus controls (39%) (OR 2.9, 95% CI 1.8-4.6, p < 0.001). This primarily reflected increased prevalence of the DRB1-0401 and 0404 and not DRB1-01 alleles. A weak contribution to disease susceptibility was also noted with carriage of the IL4 promoter -590T (OR 1.8, 95% CI 1.1-3.0, p = 0.02) and IL4 intron 3 RP1 (OR 1.7, 95% CI 1.1-2.9, p = 0.03) alleles. The TNFa +489A allele was associated with RA (OR = 2.7, 95% CI 1.5-5.1, p = 0.001) in both SE+ and SE- patients, but not with PR. Time-adjusted and multivariate Cox regression analysis revealed that only homozygosity for SE alleles was a significant independent risk factor for disease progression to chronicity in PR (hazard ratio 2.9, 95% CI 1.2-6.9, p = 0.02). However, none of 8 patients homozygous for SE- DRB1 XP4n alleles developed chronic disease after 10 years of followup (p = 0.07). CONCLUSION: The immunogenetic risk profile for PR resembles that for RA, indicating that PR is likely not an independent entity. A significant gene dose effect for SE alleles is operative in determining risk for progression from PR to RA.     

Ankylosing spondylitis and current disease-controlling agents: do they work?

In contrast to rheumatoid arthritis (RA), the concept of disease modification in ankylosing spondylitis (AS) remains to be clarified. Endpoint measures employed in AS trials primarily assess features related to symptomatology while endpoints considered more relevant to the concept of disease modification, such as spinal mobility, acute-phase reactants and radiological progression, either lack sensitivity to change or have not been comprehensively validated. NSAIDs alleviate symptoms of AS but most trials have been short term, precluding meaningful conclusions regarding disease modification. Among disease-modifying therapies used in RA, sulfasalazine has been studied in several controlled trials mostly in patients with longstanding disease, effect sizes being small and limited to those with peripheral synovitis. No conclusions can be drawn from the limited studies evaluating methotrexate.     

Systemic hematologic effects of PEG-rHuMGDF-induced megakaryocyte hyperplasia in mice

PEG-rHuMGDF injected daily in normal mice causes a rapid dose-dependent increase in megakaryocytes and platelets. At the same time that platelet numbers are increased, the mean platelet volume (MPV) and platelet distribution width (PDW) can be either decreased, normal, or increased depending on the dose and time after administration. Thus, PEG-rHuMGDF at a low dose causes decreases in MPV and PDW, MGDF at an intermediate dose causes an initial increase followed by a decrease in MPV and PDW, and PEG-rHuMGDF at higher doses causes an increase in MPV and PDW followed by a gradual normalization of these platelet indices. In addition to the expected thrombocytosis after 7 to 10 days of daily injection of high doses of PEG-rHuMGDF, a transient decrease in peripheral red blood cell numbers and hemoglobin is noted accompanied in the bone marrow by megakaryocytic hyperplasia, myeloid hyperplasia, erythroid and lymphoid hypoplasia, and deposition of a fine network of reticulin fibers. Splenomegaly, an increase in splenic megakaryocytes, and extramedullary hematopoiesis accompany the hematologic changes in the peripheral blood and marrow to complete a spectrum of pathologic features similar to those reported in patients with myelofibrosis and megakaryocyte hyperplasia. However, all the PEG-rHuMGDF-initiated hematopathology including the increase in marrow reticulin is completely and rapidly reversible upon the cessation of administration of PEG-rHuMGDF. Thus, transient hyperplastic proliferation of megakaryocytes does not cause irreversible tissue injury. Furthermore, PEG-rHuMGDF completely ameliorates carboplatin-induced thrombocytopenia at a low-dose that does not cause the hematopathology associated with myelofibrosis.