Right upper quadrant abdominal pain as the initial presentation of polyarteritis nodosa

Polyarteritis nodosa (PAN) is a necrotising vasculitis that involves medium and small vessels. PAN generally presents with constitutional, cutaneous, neurological, renal and gastrointestinal manifestations. However, PAN initially involving a single organ/system is uncommon. Here, we present a 42-year-old man who was hospitalised because of severe right upper quadrant abdominal pain that started 2 months before. Physical examination was remarkable for right upper quadrant abdominal tenderness. Abdominopelvic CT showed lymphadenopathy but no hepatic, gallbladder, pancreatic, intestinal or renal abnormalities. Abdominal angiography showed multiple small aneurysms located in the jejunal and hepatic arteries characteristic of PAN. He had a prompt and remarkable response to high-dose corticosteroids and oral cyclophosphamide. Our case, together with other reports, suggests that PAN should be considered in patients presenting with right upper abdominal pain. Timely diagnosis and treatment reduce the overall morbidity and mortality of the disease.

Clinical Manifestations Associated with Peripheral Joint Involvement in Patients with Acute Chikungunya Virus Infection

AbstractChikungunya virus (CHIKV) causes an acute febrile illness usually accompanied by severe polyarthralgia and polyarthritis. Previous studies have shown that older age, female gender, and some comorbid conditions are associated with chronic CHIKV arthritis. However, the factors associated with acute arthralgia and arthritis are not well known. Thus, we studied the clinical manifestations associated with acute peripheral joint involvement in a group of CHIKV patients from Puerto Rico. Patients with a history of fever for < 7 days evaluated at the emergency department of a university-based hospital were tested for several pathogens including CHIKV. All patients with laboratory-positive CHIKV infection were studied. Demographic features, clinical manifestations, and comorbidities were determined. Patients with and without peripheral joint involvement were compared using bivariable and multivariable analyses. In total, 172 patients with CHIKV fever were evaluated; 52.9% were women. The mean (standard deviation) age was 21.1 years (19.3). Peripheral arthralgia and/or arthritis were seen in 156 (90.7%) patients. In the multivariable analysis adjusted for age and gender, peripheral joint involvement was associated with myalgia (odds ratio [OR] = 4.65, 95% confidence interval [CI] = 1.48-14.72), back pain (OR = 16.77, 95% CI = 3.07-313.82), ocular pain (OR = 8.88, 95% CI = 1.65-165.19), headache (OR = 3.63, 95% CI = 1.06-12.53), anorexia (OR = 5.68, 95% CI = 1.87-18.97), and nausea (OR = 6.88, 95% CI = 2.05-31.49). In conclusion, in this population of patients with acute CHIKV infection, peripheral joint involvement was associated with myalgia and back pain as well as nonmusculoskeletal manifestations such as headache, ocular pain, anorexia, and nausea.

Decreased SMG7 expression associates with lupus-risk variants and elevated antinuclear antibody production

OBJECTIVES

Following up the systemic lupus erythematosus (SLE) genome-wide association studies (GWAS) identification of NMNAT2 at rs2022013, we fine-mapped its 150 kb flanking regions containing NMNAT2 and SMG7 in a 15 292 case-control multi-ancestry population and tested functions of identified variants.

METHODS

We performed genotyping using custom array, imputation by IMPUTE 2.1.2 and allele specific functions using quantitative real-time PCR and luciferase reporter transfections. SLE peripheral blood mononuclear cells (PBMCs) were cultured with small interfering RNAs to measure antinuclear antibody (ANA) and cyto/chemokine levels in supernatants using ELISA.

RESULTS

We confirmed association at NMNAT2 in European American (EA) and Amerindian/Hispanic ancestries, and identified independent signal at SMG7 tagged by rs2702178 in EA only (p=2.4×10-8, OR=1.23 (95% CI 1.14 to 1.32)). In complete linkage disequilibrium with rs2702178, rs2275675 in the promoter region robustly associated with SMG7 mRNA levels in multiple expression quantitative trait locus (eQTL) datasets. Its risk allele was dose-dependently associated with decreased SMG7 mRNA levels in PBMCs of 86 patients with SLE and 119 controls (p=1.1×10-3 and 6.8×10-8, respectively) and conferred reduced transcription activity in transfected HEK-293 (human embryonic kidney cell line) and Raji cells (p=0.0035 and 0.0037, respectively). As a critical component in the nonsense-mediated mRNA decay pathway, SMG7 could regulate autoantigens including ribonucleoprotein (RNP) and Smith (Sm). We showed SMG7 mRNA levels in PBMCs correlated inversely with ANA titres of patients with SLE (r=-0.31, p=0.01), and SMG7 knockdown increased levels of ANA IgG and chemokine (C-C motif) ligand 19 in SLE PBMCs (p=2.0×10-5 and 2.0×10-4, respectively).

CONCLUSION

We confirmed NMNAT2 and identified independent SMG7 association with SLE. The inverse relationship between levels of the risk allele-associated SMG7 mRNAs and ANA suggested the novel contribution of mRNA surveillance pathway to SLE pathogenesis.

A unique antiphospholipid assay recognizing phospholipid mixture compared with criteria antiphospholipid immunoassays in lupus patients

Background While essential for the classification of antiphospholipid syndrome (APS), anticardiolipin (aCL) assays lack specificity and anti-β2glycoproteinI (anti-β2GPI) assays lack sensitivity in this regard. Our aim was to perform a comparative analysis of the APhL ELISA assay (IgG/IgM) and criteria antiphospholipid (aPL) immunoassays in identifying APS-related clinical manifestations in a large group of patients with systemic lupus erythematosus (SLE). Methods Serum samples from 1178 patients from the Hopkins ( n = 543), LUMINA ( n = 588) and Jamaican SLE cohorts ( n = 47) were examined for IgG/IgM positivity in aCL (in-house), anti-β2GPI (two commercial kits) and APhL (Louisville APL) ELISA assays. Correlation of assay positivity with clinical manifestations and sensitivity, specificity, positive and negative predictive values and likelihood ratios were evaluated. A case series analysis was also performed in patients for whom there was isolated positivity in the specific aPL assays. Results The prevalence of aCL positivity was 34.9%, anti-β2GPI kit A was 22.6%, APhL was 11.5% and anti-β2GPI kit B was 7.6% in the study population. Anti-β2GPI kit B, aCL and APhL assays were correlated with venous thrombosis, while only APhL was significantly correlated with arterial thrombosis and consistently correlated with pregnancy-related morbidity. No significant correlations were noted for anti-β2GPI kit A. Sensitivity was greatest for aCL assays followed by anti-β2GPI kit A, APhL and anti-β2GPI kit B, while specificity was greatest and equal for anti-β2GPI kit B and APhL assays. Conclusions Overall, APhL antibodies, especially IgG, represent a promising biomarker for the classification of APS patients in the context of autoimmunity and in risk assessment with regards to pregnancy morbidity and thrombotic manifestations.

Patient-reported outcome measures in a population of medically indigent patients with systemic lupus erythematosus in Puerto Rico

Objective:

To determine patient-reported outcomes measures in indigent patients with systemic lupus erythematosus receiving their healthcare through the Puerto Rico government managed care system and compare these measures with non-indigent patients treated in a private fee-for-service setting.

Methods:

A cross-sectional study was conducted in a cohort of 98 Puerto Ricans with systemic lupus erythematosus. Patients from the public group (n = 40) were treated in a university-based specialized systemic lupus erythematosus clinic and the private group (n = 58) in a community-based rheumatology practice. Demographic and clinical features and patient-reported outcomes measures per LupusPRO instrument were determined. LupusPRO captures quality-of-life measures in 12 domains. Differences among study groups were examined using chi-square, Fisher’s exact, t-tests, and the Wilcoxon signed-rank test.

Results:

The mean (standard deviation) age of the study population was 44.9 (12.0) years; 94 (95.9%) were women. Patients in the public setting were younger and were more likely to have renal disease and elevated anti-double-stranded DNA antibodies, and being treated with azathioprine and cyclophosphamide. Patients from the public sector were more likely to have better quality-of-life measures in the LupusPRO domains of pain/vitality and coping. No significant differences were observed for the domains of lupus symptoms, physical health, emotional health, body image, cognition, procreation, lupus medications, desires/goals, social support, and satisfaction with medical care.

Conclusion:

Despite having a lower socioeconomic status and worse clinical status, systemic lupus erythematosus patients from the public sector had equal or better patient-reported outcomes measures than those treated in the private setting. This favorable outcome may be associated with the comprehensive healthcare received by these patients in a specialized lupus clinic.

Factors associated with disease expression patterns in systemic lupus erythematosus patients: results from LUMINA (LXXVII), a multiethnic US cohort

Objective

The objective of this study was to determine the association of disease expression patterns with demographic and clinical characteristics in SLE.

Methods

Patients from a multi-ethnic SLE cohort were included. Disease expression patterns were defined as acute SLE and insidious SLE; this group was divided into those who accrued three ACR criteria and then accrued the fourth (insidious pattern A) and those who have one or two and then accrued four criteria (insidious pattern B). Disease activity was ascertained with the SLAM-R and disease damage with SLICC/ACR damage index. Variables were compared using analysis of variance for numeric variables and χ2 for categorical variables. Multivariable analyses adjusting for possible confounders were performed.

Results

Six hundred and forty patients were included; the most frequent pattern was the insidious pattern B, with 415 (64.8%) patients, followed by the acute SLE group with 115 (18.0%) and the insidious pattern A with 110 (17.2%) patients. Patients from the insidious pattern A were older at diagnosis (pattern A: 39.8 vs pattern B: 36.7 vs acute: 32.4 years; p < 0.0001), more educated (13.6 vs 13.1 vs 12.1; p = 0.0008) and with a less active disease at baseline (8.8 vs 9.2 vs 10.7; p = 0.0227). Caucasian and Hispanic (Puerto Rico) ethnicities were overrepresented in this group (40.0% vs 27.7% vs 19.1% and 18.2% vs 17.1% vs 9.6%; p = 0.0003).

Conclusions

More insidious onset is associated with older age, Caucasian ethnicity, higher level of education, and lower disease activity than those with acute onset. However, after multivariable analyses, disease activity was not associated with any disease expression pattern.

Systemic lupus erythematosus in a multi-ethnic cohort (LUMINA): contributions of admixture and socioeconomic status to renal involvement

Renal involvement in systemic lupus erythematosus (SLE) is more frequent in minorities. We examined whether genetic or socioeconomic status (SES) explain these disparities in a large multiethnic (Hispanics from Texas and Puerto Rico, African Americans and Caucasians) SLE cohort. Renal involvement was defined as WHO Class II-V and/or proteinuria (>0.5 g/24 h or 3+) attributable to SLE and/or abnormal urinary sediment, proteinuria 2+, elevated serum creatinine/decreased creatinine clearance twice, 6 months apart present any time over the course of the disease. Ancestry informative markers (AIMS) were used to define the admixture proportions in each patient and group. Logistic regression models were examined to determine the percentage variance ( R2) in renal involvement related to ethnicity that is explained by socio-economic status (SES) and admixture (adjusting for age, gender and disease duration, basic model). Four-hundred and fifty-nine (out of 575) patients were included; renal involvement occurred in 44.6% Texas Hispanics, 11.3% Puerto Rico Hispanics, 45.8% African Americans, 18.3% Caucasians. SES accounted for 14.5% of the variance due to ethnicity (after adjusting for basic model variables), admixture 36.8% and both, 12.2%; 45.9% of the variance remained unexplained. Alternative models for decreased glomerula filtration rate and end-stage renal disease were comparable in the distribution of the explanatory variables. Our data indicate that genetic factors appear to be more important than SES in explaining the ethnic disparities in the occurrence of renal involvement.

Systemic lupus erythematosus in a multiethnic US cohort (LUMINA) XXVII: factors predictive of a decline to low levels of disease activity

The objective of this study was to examine factors predictive of a decline to low levels of disease activity in a cohort of systemic lupus erythematosus (SLE) patients. Patients with SLE of Hispanic (from Texas or Puerto Rico), African-American or Caucasian ethnicity from a multiethnic cohort were included. A decline to low levels of disease activity was defined as a score ≤5 as per the Systemic Lupus Activity Measure-Revised (SLAM-R) at any annual study visit if preceded by a SLAM-R 8. Using Generalized Estimating Equation (GEE), socioeconomic-demographic, behavioral, function, psychological, laboratory and clinical data [disease manifestations, number of ACR criteria accrued at diagnosis and damage accrual as per the Systemic Lupus International Collaborating Clinics (SLICC) Damage Index (SDI)] from the visit preceding that meeting the definition were examined as predictors of decline to low levels of disease activity. Two-hundred and eighty-seven patients (67 Hispanics from Texas, 32 Hispanics form Puerto Rico, 120 African-Americans and 68 Caucasians), accounting for 632 visits were analyzed. In the GEE multivariable analysis, higher degrees of social support (OR = 1.208, 95% CI 1.059-1.379; P = 0.005) were predictive of a decline to low levels of disease activity, while the number of ACR criteria accrued at diagnosis (OR = 0.765, 95% CI 0.631-0.927; P = 0.006) and damage (OR = 0.850, 95% CI 0.743-0.972, P = 0.018) were negatively associated. These data suggest that a decline to low levels of disease activity in lupus patients seems to be multifactorial; this study also underscores the importance of social support for lupus patients.

Efficacy of immunosuppressive treatment in a systemic lupus erythematosus patient presenting with inclusion body myositis

Inclusion body myositis (IBM) is an inflammatory myopathy that is generally unresponsive to immunosuppressive drugs. The coexistence of IBM with other autoimmune connective tissue diseases is rare. We present a case of a 76-year-old woman with systemic lupus erythematosus (SLE) who developed proximal muscle weakness of lower extremities and mild elevation of serum creatine kinase (CK) at 495 U/L. Muscle biopsy showed changes of endomysial inflammation and rimmed vacuoles consistent with IBM. She was treated with prednisone 40 mg daily and methotrexate 12.5 mg weekly. One month later, her physical examination showed minimal proximal weakness of lower extremities. CK levels decreased to 44 U/L. Prednisone dose was gradually decreased to 5.0 mg daily. She remained stable with normal CK levels during a follow-up period of 10 months. This case, together with other reports, suggests that IBM in the setting of SLE represents a different subtype that can benefit from immunosuppressive treatment.

Preferential association of a functional variant in complement receptor 2 with antibodies to double-stranded DNA

OBJECTIVES

Systemic lupus erythematosus (SLE; OMIM 152700) is characterised by the production of antibodies to nuclear antigens. We previously identified variants in complement receptor 2 (CR2/CD21) that were associated with decreased risk of SLE. This study aimed to identify the causal variant for this association.

METHODS

Genotyped and imputed genetic variants spanning CR2 were assessed for association with SLE in 15 750 case-control subjects from four ancestral groups. Allele-specific functional effects of associated variants were determined using quantitative real-time PCR, quantitative flow cytometry, electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP)-PCR.

RESULTS

The strongest association signal was detected at rs1876453 in intron 1 of CR2 (pmeta=4.2×10(-4), OR 0.85), specifically when subjects were stratified based on the presence of dsDNA autoantibodies (case-control pmeta=7.6×10(-7), OR 0.71; case-only pmeta=1.9×10(-4), OR 0.75). Although allele-specific effects on B cell CR2 mRNA or protein levels were not identified, levels of complement receptor 1 (CR1/CD35) mRNA and protein were significantly higher on B cells of subjects harbouring the minor allele (p=0.0248 and p=0.0006, respectively). The minor allele altered the formation of several DNA protein complexes by EMSA, including one containing CCCTC-binding factor (CTCF), an effect that was confirmed by ChIP-PCR.

CONCLUSIONS

These data suggest that rs1876453 in CR2 has long-range effects on gene regulation that decrease susceptibility to lupus. Since the minor allele at rs1876453 is preferentially associated with reduced risk of the highly specific dsDNA autoantibodies that are present in preclinical, active and severe lupus, understanding its mechanisms will have important therapeutic implications.

Clinical Manifestations Associated with Overweight/Obesity in Puerto Ricans with Fibromyalgia Syndrome

Objective. To determine the clinical manifestations associated with overweight/obesity in Hispanics from Puerto Rico with fibromyalgia syndrome (FMS). Methods. A cross-sectional study was performed in 144 patients with FMS (per American College of Rheumatology (ACR) classification criteria). Sociodemographic features, FMS-related symptoms, tender points (per ACR criteria), comorbidities, and FMS treatment were examined. BMI was calculated and patients were grouped into two categories: BMI ≤ 24.9 kg/m(2) (nonoverweight/obese) and BMI ≥ 25 kg/m(2) (overweight/obese). Bivariate and multivariate analyses were used to evaluate differences between the study groups. Results. The mean (standard deviation (SD)) age of patients was 50.2 (9.9) years; 95.1% were females and 75.7% were overweight/obese. In the bivariate analysis, overweight/obese patients were more likely to have self-reported memory impairment, anxiety, shortness of breath, and urinary frequency than nonoverweight/obese patients. In addition, the tender point count was higher in the overweight/obese group. In the logistic regression analyses, self-reported memory impairment and urinary frequency differences remained significant after adjusting for confounding variables. Conclusion. In this population of Puerto Ricans with FMS, overweight/obese patients experienced more FMS-related manifestations than nonoverweight/obese individuals. However, prospective studies are needed to confirm these associations and to elucidate if weight reduction interventions could favorably impact the severity of FMS.

Genetic associations of leptin-related polymorphisms with systemic lupus erythematosus

Leptin is abnormally elevated in the plasma of patients with systemic lupus erythematosus (SLE), where it is thought to promote and/or sustain pro-inflammatory responses. Whether this association could reflect an increased genetic susceptibility to develop SLE is not known, and studies of genetic associations with leptin-related polymorphisms in SLE patients have been so far inconclusive. Here we genotyped DNA samples from 15,706 SLE patients and healthy matched controls from four different ancestral groups, to correlate polymorphisms of genes of the leptin pathway to risk for SLE. It was found that although several SNPs showed weak associations, those associations did not remain significant after correction for multiple testing. These data do not support associations between defined leptin-related polymorphisms and increased susceptibility to develop SLE.

Clinical associations of anti-Smith antibodies in PROFILE: a multi-ethnic lupus cohort

The aim of this study was to determine the association of anti-Sm antibodies with clinical manifestations, comorbidities, and disease damage in a large multi-ethnic SLE cohort. SLE patients (per American College of Rheumatology criteria), age ≥16 years, disease duration ≤10 years at enrollment, and defined ethnicity (African American, Hispanic or Caucasian), from a longitudinal US cohort were studied. Socioeconomic-demographic features, cumulative clinical manifestations, comorbidities, and disease damage (as per the Systemic Lupus International Collaborating Clinics Damage Index [SDI]) were determined. The association of anti-Sm antibodies with clinical features was examined using multivariable logistic regression analyses adjusting for age, gender, ethnicity, disease duration, level of education, health insurance, and smoking. A total of 2322 SLE patients were studied. The mean (standard deviation, SD) age at diagnosis was 34.4 (12.8) years and the mean (SD) disease duration was 9.0 (7.9) years; 2127 (91.6%) were women. Anti-Sm antibodies were present in 579 (24.9%) patients. In the multivariable analysis, anti-Sm antibodies were significantly associated with serositis, renal involvement, psychosis, vasculitis, Raynaud's phenomenon, hemolytic anemia, leukopenia, lymphopenia, and arterial hypertension. No significant association was found for damage accrual. In this cohort of SLE patients, anti-Sm antibodies were associated with several clinical features including serious manifestations such as renal, neurologic, and hematologic disorders as well as vasculitis.

Rheumatic Manifestations in Patients with Chikungunya Infection

Chikungunya virus (CHIKV) infection is a common cause of febrile arthritis. The most common manifestations of acute infection are fever, symmetrical polyarthralgias or polyarthritis, myalgias, and maculopapular rash. Up to 80% of patients may develop musculoskeletal manifestations that persist longer than 3 months, causing impairment in their quality of life. The most common chronic manifestations are persistent or relapsing-remitting polyarthralgias, polyarthritis, and myalgias. Fingers, wrists, knees, ankles, and toes are the most frequently involved, but proximal joints and axial involvement can occur in the chronic stage. Chronic manifestations of CHIKV infection may resemble those of some autoimmune connective tissue diseases. Furthermore, CHIKV infection can cause cryoglobulinemia and may induce rheumatoid arthritis and seronegative spondyloarthropathies in genetically susceptible individuals. The Centers for Disease Control and Prevention recommend acetaminophen and non steroidal anti-inflammatory drugs for the acute rheumatic manifestations of CHIKV infection. However, some studies suggest that low-dose corticosteroids for about 1-2 months (depending on clinical course) are beneficial in relieving acute rheumatic symptoms. Conversely, hydroxychloroquine in combination with corticosteroids or other disease modifying anti-rheumatic drugs (DMARDs) has been successful in treating chronic rheumatic manifestations. Methotrexate and sulfasalazine (alone or in combination) have also been effective for chronic CHIKV arthritis. Patients with CHIKV infection should be closely monitored to identify those with chronic arthritis who would benefit from a rheumatologic evaluation and early treatment with DMARDs.

Lupus risk variants in the PXK locus alter B-cell receptor internalization

Genome wide association studies have identified variants in PXK that confer risk for humoral autoimmune diseases, including systemic lupus erythematosus (SLE or lupus), rheumatoid arthritis and more recently systemic sclerosis. While PXK is involved in trafficking of epidermal growth factor Receptor (EGFR) in COS-7 cells, mechanisms linking PXK to lupus pathophysiology have remained undefined. In an effort to uncover the mechanism at this locus that increases lupus-risk, we undertook a fine-mapping analysis in a large multi-ancestral study of lupus patients and controls. We define a large (257kb) common haplotype marking a single causal variant that confers lupus risk detected only in European ancestral populations and spans the promoter through the 3′ UTR of PXK. The strongest association was found at rs6445972 with P < 4.62 × 10⁻¹⁰, OR 0.81 (0.75–0.86). Using stepwise logistic regression analysis, we demonstrate that one signal drives the genetic association in the region. Bayesian analysis confirms our results, identifying a 95% credible set consisting of 172 variants spanning 202 kb. Functionally, we found that PXK operates on the B-cell antigen receptor (BCR); we confirmed that PXK influenced the rate of BCR internalization. Furthermore, we demonstrate that individuals carrying the risk haplotype exhibited a decreased rate of BCR internalization, a process known to impact B cell survival and cell fate. Taken together, these data define a new candidate mechanism for the genetic association of variants around PXK with lupus risk and highlight the regulation of intracellular trafficking as a genetically regulated pathway mediating human autoimmunity.

Genetic association of CD247 (CD3ζ) with SLE in a large-scale multiethnic study

A classic T-cell phenotype in systemic lupus erythematosus (SLE) is the downregulation and replacement of the CD3ζ chain that alters T-cell receptor signaling. However, genetic associations with SLE in the human CD247 locus that encodes CD3ζ are not well established and require replication in independent cohorts. Our aim was therefore to examine, localize and validate CD247-SLE association in a large multiethnic population. We typed 44 contiguous CD247 single-nucleotide polymorphisms (SNPs) in 8922 SLE patients and 8077 controls from four ethnically distinct populations. The strongest associations were found in the Asian population (11 SNPs in intron 1, 4.99 × 10(-4) < P < 4.15 × 10(-2)), where we further identified a five-marker haplotype (rs12141731-rs2949655-rs16859085-rs12144621-rs858554; G-G-A-G-A; P(hap) = 2.12 × 10(-5)) that exceeded the most associated single SNP rs858554 (minor allele frequency in controls = 13%; P = 4.99 × 10(-4), odds ratio = 1.32) in significance. Imputation and subsequent association analysis showed evidence of association (P < 0.05) at 27 additional SNPs within intron 1. Cross-ethnic meta-analysis, assuming an additive genetic model adjusted for population proportions, showed five SNPs with significant P-values (1.40 × 10(-3) < P< 3.97 × 10(-2)), with one (rs704848) remaining significant after Bonferroni correction (P(meta) = 2.66 × 10(-2)). Our study independently confirms and extends the association of SLE with CD247, which is shared by various autoimmune disorders and supports a common T-cell-mediated mechanism.

Limited systemic sclerosis initially presenting with mesenteric panniculitis

Mesenteric panniculitis pertains to a group of uncommon disorders named sclerosing mesenteritis that present with different levels of inflammation and fibrosis of the small bowel mesentery. It is associated with abdominal surgeries, trauma, malignancies, infections and connective tissue diseases. To the best of our knowledge, no cases of sclerosing mesenteritis have been reported in patients with systemic sclerosis. We present a case of a 61-year-old woman who had incidental CT findings of mesenteric panniculitis. Diagnosis was confirmed by biopsy that showed fat necrosis. On further review she had a 1-year history of Raynaud's phenomenon. Physical examination showed sclerodactyly. She had elevated anticentromere antibodies and skin biopsy was consistent with scleroderma. She was diagnosed with limited systemic sclerosis and was treated with D-penicillamine. After 6 years of follow-up, the mesenteric panniculitis and systemic sclerosis both remained stable. This case highlights the importance of considering rheumatic diseases in the differential diagnosis of sclerosing mesenteritis.

A polymorphism in TLR2 is associated with arterial thrombosis in a multiethnic population of patients with systemic lupus erythematosus

OBJECTIVE

Thrombosis is a serious complication of systemic lupus erythematosus (SLE). Studies that have investigated the genetics of thrombosis in SLE are limited. We undertook this study to assess the association of previously implicated candidate genes, particularly Toll-like receptor (TLR) genes, with pathogenesis of thrombosis.

METHODS

We genotyped 3,587 SLE patients from 3 multiethnic populations for 77 single-nucleotide polymorphisms (SNPs) in 10 genes, primarily in TLRs 2, 4, 7, and 9, and we also genotyped 64 ancestry-informative markers (AIMs). We first analyzed association with arterial and venous thrombosis in the combined population via logistic regression, adjusting for top principal components of the AIMs and other covariates. We also subjected an associated SNP, rs893629, to meta-analysis (after stratification by ethnicity and study population) to confirm the association and to test for study population or ethnicity effects.

RESULTS

In the combined analysis, the SNP rs893629 in the KIAA0922/TLR2 region was significantly associated with arterial thrombosis (logistic P = 6.4 × 10(-5) , false discovery rate P = 0.0044). Two additional SNPs in TLR2 were also suggestive: rs1816702 (logistic P = 0.002) and rs4235232 (logistic P = 0.009). In the meta-analysis by study population, the odds ratio (OR) for arterial thrombosis with rs893629 was 2.44 (95% confidence interval 1.58-3.76), without evidence for heterogeneity (P = 0.78). By ethnicity, the effect was most significant among African Americans (OR 2.42, P = 3.5 × 10(-4) ) and European Americans (OR 3.47, P = 0.024).

CONCLUSION

TLR2 gene variation is associated with thrombosis in SLE, particularly among African Americans and European Americans. There was no evidence of association among Hispanics, and results in Asian Americans were limited due to insufficient sample size. These results may help elucidate the pathogenesis of this important clinical manifestation.

The IRF5-TNPO3 association with systemic lupus erythematosus has two components that other autoimmune disorders variably share

Exploiting genotyping, DNA sequencing, imputation and trans-ancestral mapping, we used Bayesian and frequentist approaches to model the IRF5-TNPO3 locus association, now implicated in two immunotherapies and seven autoimmune diseases. Specifically, in systemic lupus erythematosus (SLE), we resolved separate associations in the IRF5 promoter (all ancestries) and with an extended European haplotype. We captured 3230 IRF5-TNPO3 high-quality, common variants across 5 ethnicities in 8395 SLE cases and 7367 controls. The genetic effect from the IRF5 promoter can be explained by any one of four variants in 5.7 kb (P-valuemeta = 6 × 10(-49); OR = 1.38-1.97). The second genetic effect spanned an 85.5-kb, 24-variant haplotype that included the genes IRF5 and TNPO3 (P-valuesEU = 10(-27)-10(-32), OR = 1.7-1.81). Many variants at the IRF5 locus with previously assigned biological function are not members of either final credible set of potential causal variants identified herein. In addition to the known biologically functional variants, we demonstrated that the risk allele of rs4728142, a variant in the promoter among the lowest frequentist probability and highest Bayesian posterior probability, was correlated with IRF5 expression and differentially binds the transcription factor ZBTB3. Our analytical strategy provides a novel framework for future studies aimed at dissecting etiological genetic effects. Finally, both SLE elements of the statistical model appear to operate in Sjögren's syndrome and systemic sclerosis whereas only the IRF5-TNPO3 gene-spanning haplotype is associated with primary biliary cirrhosis, demonstrating the nuance of similarity and difference in autoimmune disease risk mechanisms at IRF5-TNPO3.

Factors associated with tender point count in Puerto Ricans with fibromyalgia syndrome

OBJECTIVE

To examine the factors associated with fibromyalgia syndrome (FMS) tender point count (TPC) in a group of Hispanic patients from Puerto Rico.

METHODS

A cross-sectional study was performed in 144 FMS patients as determined using American College of Rheumatology [ACR] classification). Sociodemographic features, clinical manifestations, comorbidities, and pharmacologic agents were determined during the study visit. Tender points were assessed as described in the ACR classification for FMS. A t-test and one-way ANOVA test were used to examine the relationships between continuous, dichotomous, and nominal variables.

RESULTS

The mean (standard deviation, [SD]) age of the FMS patients in this study was 50.2 (9.9) years; 95.1% were females. The mean (SD) TPC was 15.0 (4.7). Dysmenorrhea, the sicca syndrome, subjective swelling, increased urinary frequency, shortness of breath, headache, constipation, paresthesia, cognitive dysfunction, arthralgia, tiredness, morning stiffness, depression, and anxiety were associated with higher TPC. No associations were seen between socio-demographic features and FMS pharmacologic therapies.

CONCLUSION

In this group of Puerto Ricans with FMS, TPC was associated with several FMS symptoms and comorbidities. This study suggests that TPC may be a simple and effective tool for assessing disease severity in FMS patients.

Fcγ receptor IIIa single-nucleotide polymorphisms and haplotypes affect human IgG binding and are associated with lupus nephritis in African Americans

OBJECTIVE

To investigate whether the Fcγ receptor IIIa-66L/R/H (FcγRIIIa-66L/R/H) polymorphism influences net effective receptor function and to assess if the FCGR3A combined genotypes formed by FcγRIIIa-66L/R/H and FcγRIIIa-176F/V, as well as copy number variation (CNV), confer risk of developing systemic lupus erythematosus (SLE) and lupus nephritis.

METHODS

FcγRIIIa variants, expressed on A20 IIA1.6 cells, were used in flow cytometry-based human IgG-binding assays. Using Pyrosequencing methodology, FCGR3A single-nucleotide polymorphism and CNV genotypes were determined in a cohort of 1,728 SLE patients and 2,404 healthy controls.

RESULTS

The FcγRIIIa-66L/R/H (rs10127939) polymorphism influenced ligand binding capacity in the presence of the FcγRIIIa-176V (rs396991) allele. There was a trend toward an association of the low-binding FcγRIIIa-176F allele with lupus nephritis among African Americans (P = 0.0609) but not among European Americans (P > 0.10). Nephritis among African American patients with SLE was associated with FcγRIIIa low-binding haplotypes containing the 66L/R/H and 176F variants (P = 0.03) and with low-binding genotype combinations (P = 0.002). No association was observed among European American patients with SLE. The distribution of FCGR3A CNV was not significantly different among controls and SLE patients with or without nephritis.

CONCLUSION

FcγRIIIa-66L/R/H influences ligand binding. The low-binding haplotypes formed by 66L/R/H and 176F confer enhanced risk of lupus nephritis in African Americans. FCGR3A CNVs are not associated with SLE or lupus nephritis in either African Americans or European Americans.