Synovial xanthomatosis: are there clues to mechanisms for this rare disease?

We report a 64-year-old man with arthritis and nodules to describe that this picture can be caused by normo-lipidemic xanthomas. Light and electron microscopy (EM) plus polymerase chain reaction (PCR) studies were performed for diagnosis and investigation. These showed features typical of xanthomas plus PCR and EM evidence of possible infection with Chlamydia pneumoniae as a pathogenetic mechanism deserving consideration. With such rare diseases, any clues to possible mechanisms seem important to record and thus to encourage future investigations. This uncommon cause of arthritis and nodules had been confused with rheumatoid arthritis by others in this case.

Associations between body mass, radiographic joint damage, adipokines and risk factors for bone loss in rheumatoid arthritis.

OBJECTIVE: To evaluate the association between BMI and radiographic joint damage (RJD) in RA. METHODS: van der Heijde-Sharp (vdHS) erosion scores were determined in 499 participants with RA, ages 18-85 years, while enrolled in a clinical trial of golimumab (GO-BEFORE trial). Subjects were MTX and biologic therapy naïve. Multivariable logistic regressions determined the odds of prevalent RJD (defined as vdHS score >10) according to BMI category. Longitudinal analyses evaluated the association between BMI category and progression of vdHS score over 52 weeks. Analyses in a subset of 100 participants examined the association between adipokines and vdHS scores. RESULTS: At enrolment and 52 weeks, 37.6 and 43.6% of participants had RJD. Compared with normal weight, obese subjects had lower odds of RJD [0.40 (95% CI 0.22, 0.74); P = 0.003], and underweight subjects had greater odds [3.86 (95% CI 1.66, 9.00); P = 0.002] at baseline, adjusted for demographic and disease characteristics. The baseline associations between BMI category and RJD were greater among participants with multiple risk factors for bone loss (female >50 years, smoking, glucocorticoid exposure and vitamin D deficiency); test for interaction P = 0.05. Adjustment for adiponectin levels did not attenuate the association between BMI and vdHS scores. Baseline BMI and change in weight did not independently predict radiographic progression (P > 0.1). CONCLUSIONS: Higher BMI was independently associated with less RJD and was greatest in participants with risk factors for bone loss. Future studies are needed to examine the associations between RJD, obesity, weight loss and osteoporosis.

Genetic and lifestyle variables associated with homocysteine concentrations and the distribution of folate derivatives in healthy premenopausal women.

BACKGROUND: Low folate and high homocysteine (Hcy) concentrations are associated with pregnancy-related pathologies such as spina bifida. Polymorphisms in folate/Hcy metabolic enzymes may contribute to this potentially pathogenic biochemical phenotype. METHODS: The study comprised 26 Caucasian and 23 African-American premenopausal women. Subjects gave fasting blood samples for biochemical phenotyping and genotyping. Total Hcy (tHcy) and both plasma and red blood cell (RBC) folate derivatives (i.e. tetrahydrofolate [THF], 5-methylTHF [5-MTHF], and 5,10-methenylTHF [5,10-MTHF]) were measured using stable isotope dilution liquid chromatography, multiple reaction monitoring, and mass spectrometry. Eleven polymorphisms from nine folate/Hcy pathway genes were genotyped. Tests of association between genetic, lifestyle, and biochemical variables were applied. RESULTS: In African American women, tHcy concentrations were associated (p < 0.05) with total RBC folate, RBC 5-MTHF, B(12), and polymorphisms in methionine synthase (MTR) and thymidylate synthase (TYMS). In Caucasian women, tHcy concentrations were not associated with total folate levels, but were associated (p < 0.05) with RBC THF, ratios of RBC 5-MTHF:THF, and polymorphisms in 5,10-methylenetetrahydrofolate reductase (MTHFR) and MTR. In African Americans, folate derivative levels were associated with smoking, B(12), and polymorphisms in MTR, TYMS, methionine synthase reductase (MTRR), and reduced folate carrier1 (RFC1). In Caucasians, folate derivative levels were associated with vitamin use, B(12), and polymorphisms in MTHFR, TYMS, and RFC1. CONCLUSIONS: Polymorphisms in the folate/Hcy pathway are associated with tHcy and folate derivative levels. In African American and Caucasian women, different factors are associated with folate/Hcy phenotypes and may contribute to race-specific differences in the risks of a range of pregnancy-related pathologies.

Genetic and biochemical determinants of serum concentrations of monocyte chemoattractant protein-1, a potential neural tube defect risk factor.

BACKGROUND: Women with the AA genotype at the (-2518)A>G promoter polymorphism of CCL-2, which encodes the potent pro-inflammatory chemokine monocyte chemoattractant protein 1 (MCP-1), may be at increased risk for having offspring affected by spina bifida. As the A allele at this locus has been associated with decreased transcription of MCP-1 mRNA relative to the G allele, the observed genetic association suggests that the risk of spina bifida may be increased in the offspring of women with low MCP-1 levels. The present study was undertaken to identify potential determinants of MCP-1 levels in women of reproductive age. METHODS: A small cohort of Caucasian and African-American women of reproductive age was recruited to participate in an exploratory investigation of the determinants of several disease-related, biochemical phenotypes, including MCP-1. Subjects completed a brief questionnaire and provided a fasting blood sample for biochemical and genetic studies. Potential biochemical, genetic, and lifestyle factors were assessed for their association with MCP-1 levels using linear regression analyses. RESULTS: In this cohort, MCP-1 levels were significantly higher in Caucasians as compared to African-Americans. Further, among women of both races, there was evidence that MCP-1 levels were associated with smoking status, MTHFR 677C>T genotype, and red blood cell tetrahydrofolate levels. CONCLUSIONS: The results of these analyses indicate that, if maternal CCL-2 genotype is related to the risk of spina bifida, this relationship is likely to be more complex than initially hypothesized, perhaps depending upon folate intake, MTHFR 677C>T genotype, the distribution of folate derivatives, and immune/inflammatory activity.

Functional polymorphisms of folate-metabolizing enzymes in relation to homocysteine concentrations in systemic lupus erythematosus.

OBJECTIVE: To determine if functional polymorphisms of folate/homocysteine pathway enzymes are associated with homocysteine concentrations and/or coronary artery calcification (CAC) scores in patients with systemic lupus erythematosus (SLE) and controls. METHODS: We investigated 163 SLE patients and 160 controls. Functional polymorphisms in 6 genes in the folate/homocysteine pathway were genotyped: 5,10-methylenetetrahydrofolate reductase (MTHFR) 677C>T, MTHFR 1298A>C, cystathionine ss-synthase (CBS) 844ins68, methionine synthase (MTR) 2756A>G, methionine synthase reductase (MTRR) 66A>G, thymidylate synthase (TYMS) 1494del6, and dihydrofolate reductase (DHFR) c.86+60_78. RESULTS: Homocysteine levels were higher in African American SLE patients than Caucasian patients and African American controls. Genotype distributions were significantly different in African American and Caucasian controls for 6 of the 7 polymorphisms. Genotype distributions for each polymorphism did not differ significantly between SLE patients and controls even after stratification by race. Glomerular filtration rate was strongly negatively correlated to homocysteine levels, and was therefore adjusted for as a covariate in the models of the effects of the polymorphisms on homocysteine levels. In SLE patients none of the 7 polymorphisms was associated with homocysteine concentrations. In Caucasian controls only MTHFR 677C>T and 1298A>C showed effects on homocysteine similar to what would be expected from the literature. There were no genotypic associations with median CAC scores in SLE patients or controls with and without stratification by race. CONCLUSION: Polymorphisms in folate/homocysteine metabolizing enzymes do not predict higher homocysteine levels or CAC scores in patients with SLE.

Monocyte chemoattractant protein-1: plasma concentrations and A(-2518)G promoter polymorphism of its gene in systemic lupus erythematosus.

OBJECTIVE: To determine (1) whether the A(-2518)G polymorphism of CCL-2, the gene encoding monocyte chemoattractant protein-1 (MCP-1), is associated with disease, MCP-1 concentration, nephritis, or coronary artery calcification (CAC) in systemic lupus erythematosus (SLE); and (2) whether MCP-1 and homocysteine (Hcy) concentrations are correlated. METHODS: Statistical tests were applied to determine the relationships between CCL-2 A(-2518)G genotypes, plasma MCP-1 concentrations, and clinical variables in Caucasian and African American patients with SLE and controls. RESULTS: The CCL-2 (-2518)G allele was not significantly associated with SLE in the whole study sample (p = 0.07). Among Caucasians, but not African Americans, G allele carriers had significantly increased risk of SLE (OR 4.2, 95% CI 1.8-9.6, p < 0.0001). Genotype was not associated with nephritis, CAC, or MCP-1 concentrations when all patients or all controls were considered; however, among recently diagnosed patients, G allele carriers had significantly higher MCP-1 concentrations than AA homozygotes (p = 0.02). SLE patients had higher MCP-1 concentrations than controls (p < 0.0001), African American patients had higher concentrations than Caucasian patients (p = 0.006), and patients with nephritis had higher concentrations than those without nephritis (p = 0.02). Although not associated with CAC, MCP-1 concentrations were significantly positively correlated with Hcy. CONCLUSION. CCL-2 A(-2518)G genotype is a significant risk factor for SLE among Caucasians but not African Americans, suggesting that genetically mandated differences in MCP-1 expression contribute to SLE etiology in the former. The positive correlation between MCP-1 and Hcy concentrations is consistent with the hypothesis that active inflammation and hyperhomocysteinemia are etiologically linked.

Homocysteine levels and disease duration independently correlate with coronary artery calcification in patients with systemic lupus erythematosus.

OBJECTIVE: To compare the incidence and extent of coronary artery calcification (CAC) as measured by electron beam computed tomography (EBCT) in patients with systemic lupus erythematosus (SLE) and controls, and to identify variables associated with CAC in patients with SLE. METHODS: Female patients with SLE and matched controls were recruited; EBCT of the coronary arteries was performed, and laboratory values (including the homocysteine concentration, the lipid level, the high-sensitivity C-reactive protein [hsCRP] concentration, the glomerular filtration rate [GFR], and the level of soluble CD154 [sCD154]) were determined. For patients, the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index and the SLE Disease Activity Index scores were recorded. Tests of association between the CAC score and the above-mentioned variables were performed. RESULTS: The incidence of CAC was higher in patients with SLE than in controls (P = 0.009), and patients had a higher mean raw CAC (rCAC) score (87.9 versus 9.6 in controls; P = 0.02). In particular, more CAC-positive patients than CAC-positive controls had rCAC scores above the 75th percentile (P = 0.003). Among both patients and controls, those with CAC were approximately 10 years older than those without CAC. In addition to age, a significant determinant of positive CAC status in both groups was the number of cardiovascular risk factors. In patients with SLE, CAC was associated with a higher homocysteine concentration, a lower GFR, and longer disease duration. In controls, the total cholesterol level correlated positively with CAC. When multivariate logistic regression methods were applied to candidate explanatory variables, homocysteine concentration, age, and disease duration (but not the levels of sCD154 or hsCRP) contributed significantly to CAC status. The methylenetetrahydrofolate reductase C677T genotype was not a predictor of hyperhomocysteinemia or CAC status. CONCLUSION: Among patients with SLE, the homocysteine concentration, the GFR, age, and disease duration were associated with CAC. CAC occurred more frequently and was more extensive in patients with SLE than in controls, suggesting that EBCT could be used to detect premature atherosclerosis in the former group. An elevated homocysteine concentration might identify patients with SLE who are likely to have premature atherosclerosis and who would benefit from evaluation of CAC by EBCT.

Behçet's disease: immunopathologic and therapeutic aspects.

Behçet's disease (BD) is a systemic inflammatory disease of unknown etiology. The disease is strongly associated with the human leukocyte antigen (HLA) B51. BD has a chronic course with periodic exacerbations and progressive deterioration. There are no specific diagnostic laboratory tests, although recurrent oral ulceration is an obligatory manifestation for diagnosis. The treatment, which includes local, systemic, or surgical therapies, is based on the severity of the illness; the most appropriate management requires a multidisciplinary approach. This paper summarizes all aspects of BD with particular emphasis on the latest immunologic and treatment aspects.