Systemic lupus erythematosus: a genetic epidemiology study of 695 patients from China

Random forests algorithm boosts genetic risk prediction of systemic lupus erythematosus

Patients with systemic lupus erythematosus (SLE) present varied clinical manifestations, posing a diagnostic challenge for physicians. Genetic factors substantially contribute to SLE development. A polygenic risk scoring (PRS) model has been used to estimate the genetic risk of SLE in individuals. However, this approach assumes independent and additive contribution of genetic variants to disease development. We aimed to improve the accuracy of SLE prediction using machine-learning algorithms. We applied random forest (RF), support vector machine (SVM), and artificial neural network (ANN) to classify SLE cases and controls using the data from our previous genome-wide association studies (GWAS) conducted in either Chinese or European populations, including a total of 19,208 participants. The overall performances of these predictors were assessed by the value of area under the receiver-operator curve (AUC). The analyses in the Chinese GWAS showed that the RF model significantly outperformed other predictors, achieving a mean AUC value of 0.84, a 13% improvement upon the PRS model (AUC = 0.74). At the optimal cut-off, the RF predictor reached a sensitivity of 84% with a specificity of 68% in SLE classification. To validate these results, similar analyses were repeated in the European GWAS, and the RF model consistently outperformed other algorithms. Our study suggests that the RF model could be an additional and powerful predictor for SLE early diagnosis.

Effect of periodontal treatment on serum inflammatory parameters and disease activity in patients with systemic lupus erythematosus: A randomized controlled trial

Background

Several descriptive studies have shown an association between periodontitis and systemic lupus erythematosus (SLE), but clinical trials evaluating the effect of periodontal treatment on serological inflammatory parameters or disease activity in SLE patients are very limited. The aim of this study was to see how periodontal treatment affects the status of SLE patients.

Materials and Methods

Ninety patients with active SLE and periodontitis were randomly assigned to one of two groups: case (oral hygiene instructions + scaling and root planning) or control (oral hygiene instructions only). Periodontal parameters, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) and SLE Disease Activity Index (SLEDAI) levels were monitored at baseline and 3 months later.

Results

Periodontal parameters in the case group were significantly reduced both statistically and clinically after 3 months. However, in the control group, these indices decreased statistically (P < 0.05) but not clinically. The score of SLEDAI in both the groups showed a significant downward trend (P < 0.05) from the start of the study, but the differences in this index between the two groups were not statistically significant (P = 0.894). Although there was a significant decrease in CRP and ESR (P = 0.001) after 3 months in the case group, indicating a positive effect of periodontal treatment on inflammation reduction, there was no significant decrease in CRP and ESR in the control group.

Conclusion

According to our findings, it appears to be no statistically significant association between periodontal treatment and SLEDAI level. However, this treatment seems to be effective in reducing acute phase biomarkers such as CRP and ESR.

Identification of 38 novel loci for systemic lupus erythematosus and genetic heterogeneity between ancestral groups

Systemic lupus erythematosus (SLE), a worldwide autoimmune disease with high heritability, shows differences in prevalence, severity and age of onset among different ancestral groups. Previous genetic studies have focused more on European populations, which appear to be the least affected. Consequently, the genetic variations that underlie the commonalities, differences and treatment options in SLE among ancestral groups have not been well elucidated. To address this, we undertake a genome-wide association study, increasing the sample size of Chinese populations to the level of existing European studies. Thirty-eight novel SLE-associated loci and incomplete sharing of genetic architecture are identified. In addition to the human leukocyte antigen (HLA) region, nine disease loci show clear ancestral differences and implicate antibody production as a potential mechanism for differences in disease manifestation. Polygenic risk scores perform significantly better when trained on ancestry-matched data sets. These analyses help to reveal the genetic basis for disparities in SLE among ancestral groups.

Synergistic activation of NF-κB by TNFAIP3 (A20) reduction and UBE2L3 (UBCH7) augment that synergistically elevate lupus risk

Background

Systemic lupus erythematosus (SLE) is an autoimmune inflammatory rheumatic disease. SLE susceptibility is affected by multiple genetic elements, environmental factors, and their interactions. We aimed in this study to statistically and functionally characterize a gene-gene interaction (epistasis) recently documented to affect SLE risk.

Methods

Two single-nucleotide polymorphisms, rs2230926 in TNFAIP3 (A20) gene and rs131654 in UBE2L3 (UBCH7) gene, were genotyped in all 3525 Korean participants, and their SLE risk association and epistasis were statistically analyzed by calculating odds ratio (OR), 95% confidence interval (CI), and P values in genotype comparisons between 1318 SLE patients and 2207 healthy controls. Furthermore, their effects on gene functions were assessed by comparatively examining separate and combined effects of TNFAIP3 and UBE2L3 knockdowns on NF-κB transcription factor activity in human cells.

Results

SLE susceptibility is associated with TNFAIP3 rs2230926 (OR = 1.9, 95% CI 1.6–2.4, P = 8.6 × 10⁻¹¹) and UBE2L3 rs131654 (OR = 1.2, 95% CI 1.1–1.4, P = 1.1 × 10⁻⁴) in a Korean population of this study. Their risk-associated alleles synergistically elevate SLE susceptibility in both multivariate logistic regression analysis (OR_interaction = 1.6, P = 0.0028) and genotype-stratified analysis (OR_interaction = 2.4), confirming the synergistic TNFAIP3-UBE2L3 interaction in SLE risk. Additionally, the SLE-susceptible alleles confer decreased TNFAIP3 expression (P = 1.1 × 10⁻⁶, n = 610) and increased UBE2L3 expression (P = 9.5 × 10⁻¹¹, n = 475), respectively, in B cell analysis of the International HapMap Project individuals with adjustment for ethnicity. Furthermore, when compared with TNFAIP3 non-knockdown and UBE2L3 knockdown in human HeLa cells, TNFAIP3 knockdown and UBE2L3 non-knockdown synergistically increase three cytokines, CCL2, CXCL8 (IL8), and IL6, all regulated by NF-κB in the human TNFR signaling pathway.

Conclusions

A synergistic interaction between TNFAIP3 and UBE2L3 genes is observed in SLE risk, as being evident in comparison of genotype distributions between SLE patients and controls. Additionally, the synergistic gene-gene interaction is functionally validated, as TNFAIP3 reduction and UBE2L3 augment exert synergism in activation of NF-κB and subsequent induction of inflammatory cytokines. Accordingly, SLE inflammation and risk could be synergistically alleviated by TNFAIP3 upregulation and UBE2L3 downregulation.

The clinical characteristics of systemic lupus erythematosus patients in Indonesia: a cohort registry from an Indonesia-based tertiary referral hospital

Introduction

To date, no national epidemiological data of systemic lupus erythematosus are available in Indonesia.

Objective

We aimed to demonstrate clinical characteristics of systemic lupus erythematosus patients of the Dr Hasan Sadikin General Hospital, one of Indonesia's top tertiary-referral hospitals.

Method

We reviewed retrospective cohort data from the Hasan Sadikin Lupus Registry, which was created in January 2016. Initial retrospective data were collected from the medical records of systemic lupus erythematosus patients from 2008 to 2015 and enhanced the cohort data from January 2016 to December 2017. The records were analysed for age, sex, clinical manifestations, comorbidity, treatment and outcome.

Results

Of 813 patients, 95.6% were females. Mean age at diagnosis was 27.7 ± 9.4 years, with a mean disease duration of 76.5 ± 53.1 months. Major clinical manifestations were arthritis (75.5%) and malar rash (68.3%). The majority of patients received steroid treatment, beside chloroquine and azathioprine. In total, 93 patients (11.4%) developed tuberculosis, 522 patients (64.2%) had routine follow-up and 66 patients (8.1%) died. Infection was the most common cause of death (36.4%).

Conclusion

Arthritis and malar rash were the most commonly encountered clinical manifestations in the Hasan Sadikin Lupus Registry. Tuberculosis incidence in systemic lupus erythematosus patients was high, as was the mortality rate of lupus.

Genetic Profiles for Systemic Lupus Erythematosus in Han Chinese Population: From Genome-Wide Association Study to Exome-Wide Association Study

Systemic lupus erythematosus (SLE) is a chronic heterogeneous autoimmune disease characterized by loss of tolerance to self-antigens, complement activation, dysregulated type 1 IFN responses, and immune-mediated tissue damage. The clinical features of SLE are pleomorphic, affecting virtually any organ system, such as skin, joints, central nervous system, or kidneys. Currently, the etiology and pathogenesis of SLE are not fully understood. Generally, it is considered that genetic factors, immune abnormalities, sex hormones, and environmental factors are associated with SLE, and mainly caused by genetic and environmental interactions, typical for a complex disease with multiple susceptibility genes. Therefore, identification of SLE susceptibility loci through molecular genetics methods may help build the foundation for identifying individuals and groups susceptible to SLE, early prevention, new drug development, and individualized treatment promoting precision medicine.

HLA-DQβ1 amino acid position 87 and DQB1*0301 are associated with Chinese Han SLE

BACKGROUND

Several susceptibility loci have been identified associated with Chinese Han systemic lupus erythematosus (SLE).

METHODS

We carried out imputation of classical HLA alleles, amino acids and Single Nucleotide Polymorphisms (SNPs) across the MHC region in Chinese Han SLE genome-wide association study (GWAS) of mainland and Hong Kong populations for the first time using newly constructed Han-MHC reference panel followed by stepwise conditional analysis.

RESULTS

We mapped the most significant independent association to HLA-DQβ1 at amino acid position (Phe87, p = 7.807 × 10-17 ) and an independent association at HLA-DQB1*0301 (Pcondiational  = 1.43 × 10-7 ).

CONCLUSION

Our study illustrates the value of population-specific HLA reference panel for fine-mapping causal variants in the MHC.

Oral Manifestations of Systemic Lupus Erythematosus Patients in Qatar: A Pilot Study

Objective

The purpose of this pilot study was to assess the prevalence of oral manifestations among systemic lupus erythematosus (SLE) patients in Qatar, in order to warrant future studies that would investigate each one of these manifestations with detail and further scrutiny.

Methods

Study procedures took place between November 2014 and April 2016. All patients visiting the outpatient rheumatology clinics at Hamad General Hospital, Doha, Qatar, were asked to join. The American College of Rheumatology (ACR) 1997 criteria of SLE were used. The patients were examined initially by a rheumatologist and were later scheduled for an appointment with a dentist at the same institution. A total of 77 patients were recruited for the study.

Results

Prevalence rates for the different oral manifestations ranged from 2.4% for soft palate ulcers, cheilitis, and oral candida to 88.1% for the presence of cavitation. Gingivitis, periodontal disease, cavities, and missing teeth were observed in more than 50% of the sample. The prevalence of periodontal disease and missing teeth was higher among those with an SLE duration > 8 years. On the contrary, the prevalence of gingivitis and cavities was higher among those with an SLE duration ≤ 8 years.

Conclusion

This study found high rates of gingivitis, periodontal disease, cavities, and missing teeth among SLE patients in Qatar. It is recommended that healthcare providers of such patients monitor the presence of any oral manifestations in order to arrange for early treatment and prevention efforts. Future prospective longitudinal studies with adequate sample size and power are needed in order to ascertain any causation factors or common etiology pathways.

Association of interleukin-10 gene single nucleotide polymorphisms with susceptibility to systemic lupus erythematosus in a Chinese population

The aim of this study was to investigate the association of interleukin (IL)-10 gene single nucleotide polymorphisms (SNPs) with susceptibility to systemic lupus erythematosus (SLE) in a Chinese population. 848 SLE patients and 461 normal controls were recruited in this study. Nine SNPs in IL-10 gene (rs1518110, rs1518111, rs1554286, rs1800890, rs1800893, rs3024493, rs3024495, rs3024498 and rs6667202) were genotyped using TaqMan genotyping assays on Fluidigm 192.24 system. The frequency of IL-10 rs3024498-C allele was significantly higher in patient group compared with control subjects (OR=5.118, 95% CI=1.819-14.405, P=0.002). No significant differences were detected for the distribution of allele and genotype frequencies of other eight SNPs between patients with SLE and controls after Bonferroni correction (all P>0.0056). Interestingly, significant differences were detected both in the allele and genotype frequencies of rs3024498 between SLE patients with and without arthritis (P=0.002, P=0.022, respectively).There was significant difference in genotype frequency at rs3024498 between SLE patients with and without malar rash (P=0.040). And, there was significant difference in allele frequency at rs3024498 between SLE patients with and without anti-double-stranded DNA (P=0.032). Meanwhile, significant difference in genotype frequency at rs1518110 and rs1518111 were found in patients with and without lupus headache (P=0.025, P=0.038, respectively). There were significant difference in allele and genotype frequency at rs1800890 and rs6667202 between SLE patients with and without thrombocytopenia (rs1800890: P=0.016, P=0.026, respectively; rs6667202: P=0.007, P=0.007, respectively). Further, significant difference were observed both in allele frequency and in genotype distribution of rs1800893 between patients with and without tubular urine and proteinuria (tubular urine: P<0.001, P=0.003, respectively; proteinuria: P=0.001, P=0.018, respectively). In summary, IL-10 rs3024498 polymorphism might contribute to SLE susceptibility and several clinical phenotypes.

Systemic lupus erythematosus with and without a family history: a meta-analysis

Objective The objective of this paper is to investigate the association of clinical manifestations and laboratory parameters between familial systemic lupus erythematosus (SLE) and sporadic SLE. Methods All relevant literature was retrieved from the PubMed, EMBASE, Web of Science and China National Knowledge Infrastructure (CNKI) databases. The qualities of these studies were evaluated using a modified version of the Newcastle-Ottawa scale. The characteristics and clinical manifestations of involved individuals were extracted from each study. Pooled odds ratio (OR) was calculated using the random effects-method, and the heterogeneity between studies was quantified using the I² statistic. Results Of 330 studies identified by the search strategy, six were included in this review. In total, 733 cases were familial SLE and 1405 were sporadic SLE. Analysis revealed that photosensitivity, nephritis and thrombocytopenia were negatively associated with familial SLE, with OR (95% CI) values of 0.73 (0.60-0.89), 0.72 (0.59-0.88) and 0.75 (0.57-0.98), respectively. Conclusions Photosensitivity, thrombocytopenia and renal involvement could be more common in non-familial SLE, which should be further confirmed by well-designed studies with large populations.

Multiple variants in 5q31.1 are associated with systemic lupus erythematosus susceptibility and subphenotypes in the Han Chinese population

BACKGROUND

A previous study provided evidence for a genetic association between PPP2CA on 5q31.1 and systemic lupus erythematosus (SLE) across multi-ancestral cohorts, but failed to find significant evidence for an association in the Han Chinese population.

OBJECTIVES

To explore the association between this locus and SLE using data from our previously published genome-wide association study (GWAS).

METHODS

Single-nucleotide polymorphisms (SNPs) rs7726414 and rs244689 (near TCF7 and PPP2CA in 5q31.1) were selected as candidate independent associations from a large-scale study in a Han Chinese population consisting of 1047 cases and 1205 controls. Subsequently, 3509 cases and 8246 controls were genotyped in two further replication studies. We then investigated the SNPs' associations with SLE subphenotypes and gene expression in peripheral blood mononuclear cells.

RESULTS

Highly significant associations with SLE in the Han Chinese population were detected for SNPs rs7726414 and rs244689 by combining the genotype data from our previous GWAS and two independent replication cohorts. Further conditional analyses indicated that these two SNPs contribute to disease susceptibility independently. A significant association with SLE, age at diagnosis < 20 years, was found for rs7726414 (P = 0·001). The expression levels of TCF7 and PPP2CA messenger RNA in patients with SLE were significantly decreased compared with those in healthy controls.

CONCLUSIONS

This study found evidence for multiple associations with SLE in 5q31.1 at genome-wide levels of significance for the first time in a Han Chinese population, in a combined genotype dataset. These findings suggest that variants in the 5q31.1 locus not only provide novel insights into the genetic architecture of SLE, but also contribute to the complex subphenotypes of SLE.

A systematic review and meta-analysis of cutaneous manifestations in late- versus early-onset systemic lupus erythematosus

OBJECTIVES

Although systemic lupus erythematosus (SLE) most commonly occurs in reproductive-age women, some are diagnosed after the age of 50. Recognizing that greater than one-third of SLE criteria are cutaneous, we undertook a systematic review and meta-analysis to evaluate differences in cutaneous manifestations in early- and late-onset SLE patients.

METHODS

We searched the literature using PubMed, CINAHL, Web of Science, and Cochrane Library. We excluded studies that did not include ACR SLE classification criteria, early-onset controls, that defined late-onset SLE as <50 years of age, or were not written in English. Two authors rated study quality using the Newcastle Ottawa Quality Scale. We used Forest plots to compare odds ratios (95% CI) of cutaneous manifestations by age. Study heterogeneity was assessed using I(2).

RESULTS

Overall, 35 studies, representing 11,189 early-onset and 1727 late-onset patients with SLE, met eligibility criteria. The female:male ratio was lower in the late-onset group (5:1 versus 8:1). Most cutaneous manifestations were less prevalent in the late-onset group. In particular, malar rash [OR = 0.43 (0.35, 0.52)], photosensitivity [OR = 0.72 (0.59, 0.88)], and livedo reticularis [OR = 0.33 (0.17, 0.64)] were less common in late-onset patients. In contrast, sicca symptoms were more common [OR = 2.45 (1.91, 3.14)]. The mean Newcastle Ottawa Quality Scale score was 6.3 ± 0.5 (scale: 0-9) with high inter-rater reliability for the score (0.96).

CONCLUSIONS

Overall, cutaneous manifestations are less common in late-onset SLE patients, except sicca symptoms. Future studies should investigate etiologies for this phenomenon including roles of immune senescence, environment, gender, and immunogenetics.

Familial Aggregation and Segregation Analysis in Families Presenting Autoimmunity, Polyautoimmunity, and Multiple Autoimmune Syndrome

Studies documenting increased risk of developing autoimmune diseases (ADs) have shown that these conditions share several immunogenetic mechanisms (i.e., the autoimmune tautology). This report explored familial aggregation and segregation of AD, polyautoimmunity, and multiple autoimmune syndrome (MAS) in 210 families. Familial aggregation was examined for first-degree relatives. Segregation analysis was implemented as in S.A.G.E. release 6.3. Data showed differences between late- and early-onset families regarding their age, age of onset, and sex. Familial aggregation of AD in late- and early-onset families was observed. For polyautoimmunity as a trait, only aggregation was observed between sibling pairs in late-onset families. No aggregation was observed for MAS. Segregation analyses for AD suggested major gene(s) with no clear discernible classical known Mendelian transmission in late-onset families, while for polyautoimmunity and MAS no model was implied. Data suggest that polyautoimmunity and MAS are not independent traits and that gender, age, and age of onset are interrelated factors influencing autoimmunity.

A mega-analysis of genome-wide association studies for major depressive disorder

Prior genome-wide association studies (GWAS) of major depressive disorder (MDD) have met with limited success. We sought to increase statistical power to detect disease loci by conducting a GWAS mega-analysis for MDD. In the MDD discovery phase, we analyzed more than 1.2 million autosomal and X chromosome single-nucleotide polymorphisms (SNPs) in 18 759 independent and unrelated subjects of recent European ancestry (9240 MDD cases and 9519 controls). In the MDD replication phase, we evaluated 554 SNPs in independent samples (6783 MDD cases and 50 695 controls). We also conducted a cross-disorder meta-analysis using 819 autosomal SNPs with P<0.0001 for either MDD or the Psychiatric GWAS Consortium bipolar disorder (BIP) mega-analysis (9238 MDD cases/8039 controls and 6998 BIP cases/7775 controls). No SNPs achieved genome-wide significance in the MDD discovery phase, the MDD replication phase or in pre-planned secondary analyses (by sex, recurrent MDD, recurrent early-onset MDD, age of onset, pre-pubertal onset MDD or typical-like MDD from a latent class analyses of the MDD criteria). In the MDD-bipolar cross-disorder analysis, 15 SNPs exceeded genome-wide significance (P<5 × 10(-8)), and all were in a 248 kb interval of high LD on 3p21.1 (chr3:52 425 083-53 822 102, minimum P=5.9 × 10(-9) at rs2535629). Although this is the largest genome-wide analysis of MDD yet conducted, its high prevalence means that the sample is still underpowered to detect genetic effects typical for complex traits. Therefore, we were unable to identify robust and replicable findings. We discuss what this means for genetic research for MDD. The 3p21.1 MDD-BIP finding should be interpreted with caution as the most significant SNP did not replicate in MDD samples, and genotyping in independent samples will be needed to resolve its status.

Genetic epidemiology and heritability of AIS: A study of 415 Chinese female patients

Recent familial segregation studies supported a multifactorial genetic model for the etiology of adolescent idiopathic scoliosis (AIS). However, the extent of quantitative genetic effects, such as heritability, have not been fully evaluated. This genetic epidemiology study examined the sibling recurrent risk and heritability of AIS in first-degree relatives of 415 Chinese female patients, which is up to now the largest cohort. They were first diagnosed by community screening program and compared to 203 age-matched normal controls. Out of the total 531 sibs of AIS cases, 94 sibs had scoliosis (sibling recurrence risk = 17.7%). The prevalence of AIS among male and female sibs of an index case were 11.5% (95% CI = 7.5-15.5) and 23.0% (95% CI = 18.1-27.9), respectively. Female sibs of an index case had an increased risk of 8.9-fold (95% CI = 3.2-34.4) for developing AIS. These recurrent risks were significantly higher than the risk in the control group (p < 0.0001). Overall, heritability was estimated to be 87.5 ± 11.1%. The results confirmed the prevailing impression of strong genetic influence on the risk of AIS. Here we provided a large-scale study for the genetic aggregation estimates in an Asian population for the first time. The finding also positioned AIS among other common disease or complex traits with a high heritability.

IKZF1: a critical role in the pathogenesis of systemic lupus erythematosus?

Ikaros family zinc finger 1, encoded by IKZF1, are lymphoid-restricted zinc finger transcription factors that share common N-terminal Kruppel-like zinc finger DNA-binding domain. IKZF1 play multiple important roles on regulators of lymphocyte differentiation and hematological tumor suppressor. Our genome-wide association (GWA) studies in systemic lupus erythematosus (SLE) independently identified genetic variants in IKZF1 associated with SLE, which are supported by other studies. Previous studies found that lower expression of IKZF1 may play critical roles in activating some signal pathways involved in SLE, such as signal transducers and activators of transcription (STAT)4 and interferon pathways. In addition, IKZF1 has been implicated in roles involved in some hematologic traits or abnormalities, such as erythrocyte measures, myelofibrosis, and acute lymphoblastic leukemia (ALL), which may be common clinical manifestations or co-occurrence hematological diseases of patients with SLE. All these findings suggest that IKZF1 may play a critical role in the pathogenesis of SLE. In this article, we discuss the existing understanding of the role of IKZF1 on the physiological and pathological functions associated with SLE, providing insights that may assist in the development of new therapeutic strategies based on IKZF1 for patients with SLE.

Role of cytokines in systemic lupus erythematosus: recent progress from GWAS and sequencing

Systemic lupus erythematosus (SLE) is a complex autoimmune disorder, known to have a strong genetic component. Concordance between monozygotic twins is approximately 30-40%, which is 8-20 times higher than that of dizygotic twins. In the last decade, genome-wide approaches to understanding SLE have yielded many candidate genes, which are important to understanding the pathophysiology of the disease and potential targets for pharmaceutical intervention. In this paper, we focus on the role of cytokines and examine how genome-wide association studies, copy number variation studies, and next-generation sequencing are being employed to understand the etiology of SLE. Prominent genes identified by these approaches include BLK, FCγR3B, and TREX1. Our goal is to present a brief overview of genomic approaches to SLE and to introduce some of the key discussion points pertinent to the field.

Genome-wide association study of skin complex diseases

Complex diseases are caused by both genetic and environmental factors. Over decades, scientists endeavored to uncover the genetic myth of complex diseases by linkage and association studies. Since 2005, the genome-wide association study (GWAS) has been proved to be the most powerful and efficient study design thus far in identifying genetic variants that are associated with complex diseases. More than 230 complex diseases and traits have been investigated by this approach. In dermatology, 10 skin complex diseases have been investigated, a wealth of common susceptibility variants conferring risk for skin complex diseases have been discovered. These findings point to genes and/or loci involved in biological systems worth further investigating by using other methodologies. Certainly, as our understanding of the genetic etiology of skin complex diseases continues to mature, important opportunities will emerge for developing more effective diagnostic and clinical management tools for these diseases.

Severe diffuse non-scarring hair loss in systemic lupus erythematosus - clinical and histopathological analysis of four cases

BACKGROUND

Although diffuse non-scarring hair loss been found common in systemic lupus erythematosus (SLE), study that conduted on the severe type has been scarce.

OBJECTIVE

This study aims to explore the dermoscopic and pathological features of severe diffuse hair loss in SLE.

METHOD

Data including clinico-laboratory, dermoscopic and histopathological findings of four patients with SLE with severe diffuse hair loss were analysed retrospectively.

RESULTS

All four patients were women aged 41, 39, 14 and 48 with complaints of hair loss involving 55%, 100%, 60% and 55% of their scalp respectively. Common clinical findings observed in the patients were sparse scalp hair with clusters of newly regrown hair. Scalp dermoscopy showed scaling, perifollicular telangiectasia, increased numbers of short vellus hairs, focal atrichia and decreased hair shaft pigmentation. Scalp tissue histopathology revealed typical changes of SLE such as epidermal atrophy with focal liquefaction, degeneration of the basement membrane zone, pigment incontinence, mild focal perivascular and perifollicular lymphocytic infiltrates and deposition of immunoglobulins at the dermal-epidermal junction. Treatment and improvement in SLE disease activity indices had a favourable impact on hair regrowth.

CONCLUSION

The severe type of hair loss in patient with SLE presents a unique set of clinical, dermoscopic and histopathological features.

A genetic epidemiological survey of idiopathic epilepsy in the Chinese Han population

BACKGROUND

Idiopathic epilepsy (IE) is a syndrome that comprises epilepsy only, with no underlying structural brain lesion or other neurological signs or symptoms. Numerous studies have shown that genetic factors play an important role in IE. IE is a common disease in the Chinese Han population. However, the genetic epidemiological characteristics of IE in the Chinese population, such as its heritability and genetic models remain unclear.

PURPOSE

To study the clinical and epidemiological profile of IE, to estimate the heritability and determine the possible genetic models for IE in the Chinese Han population.

METHODS

A case-control family-based study was carried out in a rural Chinese county. We collected data from eligible IE patients, controls, and their relatives by a uniform structured questionnaire, and then established an epidemiologic database of epilepsy using Access2010. General statistical and genetic epidemiological analyses (Falconer's-method-based heritability, simple segregation ratio and complex segregation analysis) were performed using SAS9.1 and the SAGE-SEGREG program.

RESULTS

(1) The prevalence of IE among the relatives of probands with IE (2.75‰) was higher than that among the relatives of the control group (0.61‰). The prevalence of IE among the first-, second-, and third-degree relatives of the probands with IE was 11.45‰, 2.64‰ and 0.98‰, respectively, which were all higher than the corresponding prevalences in the relatives of controls. Trend-chi-squared tests indicated that the prevalence of epilepsy increased among the relatives of probands with decreasing kinship distance (χ(2)=97.16, P=0.00). (2) The heritability of IE among first-, second-, and third-degree relatives was 55.06%, 50.72% and 16.98%, respectively. The weighted mean heritability was 46.07%. (3) The simple segregation ratio of IE was 0.03, significantly lower than the Mendelian recessive segregation ratio of 0.25. Complex segregation analysis showed that the population we studied accepted a Mendelian genetic model (dominant, recessive, additive, and a major gene model) and excluded the general model, non-transmitted model, and environment-only model. A Mendelian additive inheritance model was ultimately the best-fit because it had the lowest Akaike Information Criteria score.

CONCLUSION

In the Chinese Han population, IE follows a pattern of polygenic Mendelian additive inheritance rather than single-gene inheritance. Nearly half of the total variance can be explained by genetic factors.

Confirmation of C4 gene copy number variation and the association with systemic lupus erythematosus in Chinese Han population

The distribution of complement component 4 (C4) gene copy number (GCN) has been validated in European populations. Meanwhile, C4 gene has been identified as a susceptibility gene for systemic lupus erythematosus (SLE). However, the association and the possible phenotype significance remain to be determined intensely in the Chinese population. This study was designed to validate the distribution of C4 GCNs in Chinese Han and the correlation between C4 GCNs and SLE using quantitative real-time polymerase chain reaction in 924 SLE patients and 1,007 controls. The results presented distribution of C4 GCNs in healthy populations and also showed that lower C4 GCN was a risk factor for SLE and higher C4 GCN was a protective factor against the disease susceptibility, which was similar to the report in the Caucasian population. Furthermore, we found the association between C4A GCN and disease subphenotypes of arthritis with SLE. We conclude that the association of C4 GCN with SLE was replicated in Chinese Han population, which highlighted the importance of C4 in SLE pathogenesis of diverse populations.

Late onset lupus nephritis in Chinese patients: classified by the 2003 International Society of Nephrology and Renal Pathology Society system

AIM

The aim of this study was to assess clinicopathological characteristics and outcomes of a cohort of Chinese patients with late onset lupus nephritis.

METHODS

Clinical, pathological and outcome data for patients with late onset lupus nephritis (onset at age ≥50 years) and early onset lupus nephritis (onset at age ≤40 years) were retrospectively analyzed and compared.

RESULTS

Among 271 patients with renal biopsy-proven lupus nephritis, 30 were identified as having late onset lupus nephritis and 241 were identified as having early onset lupus nephritis. Lower female predominance was observed in the late onset patients (p = 0.06). The interval between presentation of lupus nephritis and diagnosis was significantly longer in the late onset group than in the early onset group (p = 0.003). In comparison with early onset group, patients in the late onset group had significantly lower scores for endocapillary hypercellularity (p = 0.041), subendothelial hyaline deposits (p = 0.022) and glomerular leukocyte infiltration (p = 0.032), but had significantly higher scores for tubular atrophy (p = 0.037) and interstitial fibrosis (p = 0.018). Regarding long-term survival and renal outcome, there was no significant difference between the two groups, although it seemed that the early onset group had a poorer renal outcome (p = 0.077, hazard ratio (HR) = 3.909, 95% CI: 0.862-17.726).

CONCLUSIONS

Patients with late onset lupus nephritis were usually diagnosed later; they had milder active lesions and more severe chronic lesions in renal pathology. However, the renal outcome was similar between late and early onset patients.

Epidemiology of systemic lupus erythematosus in Asia

In this paper we aim to review the prevalence, incidence and disease presentation of lupus patients in Asian populations. The database of the National Library of Medicine (MEDLINE) through PUBMED up to September 2009 was searched for relevant articles using the search terms 'systemic lupus erythematosus', 'epidemiology', and 'Asia'. Articles on lupus prevalence, incidence, and clinical manifestations were retrieved and their bibliographies further screened for relevant articles. Proceedings of national, regional, and international rheumatology and SLE conferences were likewise searched for relevant abstracts. Retrieval rate of relevant articles was approximately 80%. Prevalence and incidence figures are expressed per 100,000 populations. Among the articles reviewed, epidemiologic information was usually obtained through population surveys or hospital cohorts. Prevalence data are available from 24 countries, and generally fall within 30-50/100,000 population. However, one survey showed a higher prevalence of 70 (Shanghai), while three others showed a lower prevalence of 3.2-19.3 (India, Japan, Saudi Arabia). Only three countries have recorded incidence rates and these varied from 0.9 to 3.1 per annum. Thirty articles from 21 countries describe lupus disease presentation. Common manifestations include mucocutaneous lesions (seen in 52-98% of patients) and arthritis/musculoskeletal complaints (36-95%). Antinuclear antibodies were generally positive in 89-100% of patients, except for two studies. Renal involvement ranged from 18% to 100% with most articles reporting this in >50% of their patients. Discoid lesions, serositis, and neurologic involvement were the least frequently seen symptoms. There is varying epidemiologic information regarding systemic lupus erythematosus among countries in Asia. Prevalence rates usually fall within 30-50/100,000 population. Incidence rates, as reported from three countries, varied from 0.9/100,000 to 3.1% per annum. It is difficult to make generalizations about how the epidemiologic character of the disease varies from country to country. However, similarities in disease manifestations can be observed. .

Early disease onset is predicted by a higher genetic risk for lupus and is associated with a more severe phenotype in lupus patients

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic, multiorgan, autoimmune disease that affects people of all ages and ethnicities.

OBJECTIVES

To explore the relationship between age at disease onset and many of the diverse manifestations of SLE. Additionally, to determine the relationship between age of disease onset and genetic risk in patients with SLE.

METHODS

The relationship between the age at disease onset and SLE manifestations were explored in a multi-racial cohort of 1317 patients. Patients with SLE were genotyped across 19 confirmed genetic susceptibility loci for SLE. Logistic regression was used to determine the relationships between the number of risk alleles present and age of disease onset.

RESULTS

Childhood-onset SLE had higher odds of proteinuria, malar rash, anti-dsDNA antibody, haemolytic anaemia, arthritis and leucopenia (OR=3.03, 2.13, 2.08, 2.50, 1.89, 1.53, respectively; p values <0.0001, 0.0004, 0.0005, 0.0024, 0.0114, 0.045, respectively). In female subjects, the odds of having cellular casts were 2.18 times higher in childhood-onset than in adult-onset SLE (p=0.0027). With age of onset ≥50, the odds of having proteinuria, cellular casts, anti-nRNP antibody, anti-Sm antibody, anti-dsDNA antibody and seizures were reduced. However, late adult-onset patients with SLE have higher odds of developing photosensitivity than early adult-onset patients. Each SLE-susceptibility risk allele carried within the genome of patients with SLE increased the odds of having a childhood-onset disease in a race-specific manner: by an average of 48% in Gullah and 25% in African-Americans, but this was not significant in Hispanic and European-American lupus patients.

CONCLUSIONS

The genetic contribution towards predicting early-onset disease in patients with SLE is quantified for the first time. A more severe SLE phenotype is found in patients with early-onset disease in a large multi-racial cohort, independent of gender, race and disease duration.

Analysis of adiponectin gene polymorphisms in Chinese population with systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a prototypic systemic autoimmune disease. Adiponectin is an adipocyte-derived cytokine with anti-inflammatory, antidiabetic, and antiatherogenic properties. No study has reported on the association between adiponectin (ADIPOQ) gene and SLE. Our aim is to investigate the association between single-nucleotide polymorphisms in ADIPOQ gene and SLE. We examined 179 SLE patients and 237 age- and gender-matched controls from Sichuan province in China. Genotypes were determined using polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing. Results show that there was no significant difference in the allele frequencies of rs1501299 (P = .311, OR = 1.17, 95% CI: 0.86-1.59) and rs2241766 (P = .929, OR = 0.99, 95% CI: 0.74-1.33) in ADIPOQ gene between SLE patients and controls. The same results were seen in their genotypes (P < .05). The allele frequencies of rs1501299 and rs2241766 polymorphisms of ADIPOQ may not be associated with SLE risk.

Clinical Features and Prognosis of Late-onset Systemic Lupus Erythematosus: Results from the 1000 Faces of Lupus Study

Objective.

There is controversy whether older-onset systemic lupus erythematosus (SLE) is associated with a different, more benign disease course than in younger-onset SLE. Our objective was to characterize the clinical features and prognosis of late-onset SLE in a large, multicenter cohort.

Methods.

We studied adult-onset lupus in the 1000 Canadian Faces of Lupus cohort (n = 1528) of whom 10.5% had onset at age ≥ 50 years versus a control group with onset at < 50 years.

Results.

Disease duration was different in early- and late-onset groups (15 yrs in early vs 9.3 yrs in late; p < 0.001). Caucasians were represented more in the later-onset SLE group (55.6% vs 74.5%), while Asians and Blacks were more prevalent in the younger group. Younger-onset SLE subjects fulfilled more American College of Rheumatology criteria for SLE (< 50 yrs: 5.98 ± 1.68; ≥ 50 yrs: 5.24 ± 1.44; p < 0.0001). Despite an equal prevalence of anti-dsDNA, the younger-onset group more often had positive anti-Smith autoantibody, ribonucleoprotein, and hypocomplementemia, and more nephritis, rash, and cytopenias than the older-onset group. However, disease activity and damage accrual were higher in the older-onset group. The older patients received less prednisone and immunosuppressives (current and ever-use). As expected, comorbidity was higher in the older-onset SLE group.

Conclusion.

This study suggests that older age-onset SLE is not benign. There may be an interaction between lupus and age in which, although there is less lupus nephritis in the elderly, more disease activity and damage are present.

Genome-wide association study in a Chinese Han population identifies nine new susceptibility loci for systemic lupus erythematosus

We performed a genome-wide association study (GWAS) of systemic lupus erythematosus (SLE) in a Chinese Han population by genotyping 1,047 cases and 1,205 controls using Illumina Human610-Quad BeadChips and replicating 78 SNPs in two additional cohorts (3,152 cases and 7,050 controls). We identified nine new susceptibility loci (ETS1, IKZF1, RASGRP3, SLC15A4, TNIP1, 7q11.23, 10q11.22, 11q23.3 and 16p11.2; 1.77 x 10(-25) < or = P(combined) < or = 2.77 x 10(-8)) and confirmed seven previously reported loci (BLK, IRF5, STAT4, TNFAIP3, TNFSF4, 6q21 and 22q11.21; 5.17 x 10(-42) < or = P(combined) < or = 5.18 x 10(-12)). Comparison with previous GWAS findings highlighted the genetic heterogeneity of SLE susceptibility between Chinese Han and European populations. This study not only advances our understanding of the genetic basis of SLE but also highlights the value of performing GWAS in diverse ancestral populations.

Takayasu arteritis and giant cell arteritis: a spectrum within the same disease?

Giant cell arteritis (GCA) and Takayasu arteritis (TAK) have been considered distinct disorders based on their clinical features, age of onset, and ethnic distribution. However, on closer examination, these disorders appear more similar than different. The histopathology of arterial lesions in these diseases may be indistinguishable. Imaging studies have revealed large vessel inflammation in at least 60% of patients with GCA. We questioned whether the distinctions between these diseases might in part be an artifact due to bias in gathering historical and physical data. We postulated that signs and symptoms of GCA and polymyalgia rheumatica occur in patients with TAK but have been under-reported as a result of this bias.We performed a retrospective review of 75 patients with TAK and 69 patients with GCA (per American College of Rheumatology criteria). Signs and symptoms attributable to disease within the year before and following diagnosis, treatment and interventional outcomes, and mortality were recorded using a standardized database. All cases were evaluated by a single physician, using identical history and physical examination forms for patients with both diseases.Patients were predominantly female (TAK 91%, GCA 82%) and white (TAK 88%, GCA 95%). New headache was a presenting symptom in 52% of TAK and in 70% of GCA patients. All TAK patients underwent vascular imaging studies and were demonstrated to have large vessel abnormalities. However, only a subset of patients with GCA (43/69, 62%) was similarly studied. Among this group, 73% of GCA patients had at least 1 arterial lesion identified. In both TAK and GCA, the most common sites of involvement were the aorta (TAK 77%, GCA 65%) and subclavian (TAK 65%, GCA 37%) arteries. Compared to patients with TAK, patients with GCA had a greater prevalence of jaw claudication (GCA 33%, TAK 5%), blurred vision (GCA 29%, TAK 8%), diplopia (GCA 9%, TAK 0%), and blindness (GCA 14%, TAK 0%).Symptoms, signs, and imaging abnormalities that are characteristic of GCA or TAK are often present, albeit in differing frequencies, in both disorders. These findings lend support to the hypothesis that these diseases may not be distinct entities, but represent skewed phenotypes within the spectrum of a single disorder. Differences in frequencies of manifestations may reflect a significant bias in how data are gathered for patients with each disease, as well as the influence of vascular and immunologic senescence.

[Hemophagocytic syndrome in late-onset SLE patients]

We report two elderly male patients with hemophagocytic syndrome (HPS) associated with systemic lupus erythematosus (SLE). They were admitted to the hospital because of general malaise. At admission, they showed fever of unknown origin and hematological abnormalities without typical symptoms for SLE such as arthralgia or malar rash. Chest X-rays, computed tomography and cardiac sonogram demonstrated unilateral pleural and pericardial effusions. Bone marrow aspiration revealed hypocellular marrow with increased macrophages phagocytosing blood cells in the both cases. One patient had positive reactivity for direct Coombs's test and high level of platelet-associated antibody, whose symptoms were ameliorated only by 20 mg per day of prednisolone. The other patient, however, progressive worsened and died regardless of intensive treatment containing methyl-prednisolone pulse therapy. Late-onset lupus (LO-SLE) patients tend to have a more insidious onset of disease, and less frequently show typical symptoms of early-onset SLE such as malar rash. So it seems to be important that clinicians make a fast diagnosis and proper treatment for LO-SLE and associated HPS by careful observation for the latent symptoms and laboratory findings.

Clinical and serological correlates of anti-Sm autoantibodies in Chinese patients with systemic lupus erythematosus: 1,584 cases

To investigate the association of anti-Sm antibodies with clinical and serological features in systemic lupus erythematosus. A group of 1,584 patients with SLE was recruited. Clinical and laboratory data were compared between patients with and without anti-Sm antibodies. There were 1,424 females and 160 males, the mean age of the patients was 33.2 +/- 12.3 years, and the mean duration of disease was 32.5 +/- 59.4 months. A total of 469 (29.6%) were anti-Sm antibodies positive. The presence of anti-Sm antibodies was associated with arthritis, renal involvement, malar rash, vasculitis and low serum complement C3. The positive rate of anti-nuclear, anti-dsDNA, anti-La/SSB and anti-U1RNP antibodies were significant higher in anti-Sm positive group when compared with anti-Sm negative group. A trend towards a higher presence of anti-Sm antibodies related to an early disease onset was observed. In conclusion, Anti-Sm antibodies are associated with lupus related clinical and laboratory profiles and correlated significantly with disease activity.

Comparison between familial and sporadic systemic lupus erythematosus in Kuwaiti patients

To validate the use of multiplex case families in studying the pathogenesis of systemic lupus erythematosus (SLE), we investigated the pattern of familial SLE in relation to sporadic SLE in the highly consanguineous Kuwaiti population. We sought to determine whether familial and sporadic SLEs have the same clinical and serological features. We compared 21 cases of familial SLE in 21 families with 42 non-familial SLE controls matched for age, sex and duration of disease. Twenty-one families, in which the diagnosis of SLE was verified in at least two relatives, were included in the study. The diagnosis was made according to the revised 1982 American College of Rheumatology criteria. There were no significant differences in clinical features or serological manifestations between familial SLE cases and their matched controls. However, our results showed that the frequency of La/SSB antibodies was higher in the sporadic group (P = 0.048), although this was not significant after application of Bonferroni's correction for the number of comparisons. Familial cases of SLE were more likely to present at younger age of 20 years and sporadic cases at 26 years (P = 0.006). The prevalence of familial SLE was 27.4%. We have found that familial and sporadic cases of SLE are broadly similar, and it is justified to include multiple case families in genetic studies.

Genetic contributions to the autoantibody profile in a rabbit model of Systemic Lupus Erythematosus (SLE)

For the development of rabbit models of Systemic Lupus Erythematosus (SLE), immunoglobulin allotype-defined pedigreed rabbits from the National Institute of Allergy and Infectious Diseases rabbit resource more closely approximate human populations due to their non-inbred pedigreed structure. In an initial study from this laboratory, peptides (SM and GR) from the spliceosomal Smith (Sm) and the NMDA glutamate receptor NR2b, on branched polylysine backbones (BB) elicited antinuclear and anti-dsDNA autoantibodies typical of SLE, as well as seizures and nystagmus sometimes observed as neurological manifestations in SLE patients. This suggested the feasibility of further selective breeding to develop a more reproducible rabbit model for investigations of SLE. Here we report the results of GR-MAP-8 and control BB immunization on autoantibody responses in a group of 24 rabbits specifically bred and developed from parents and ancestors tested for autoantibody responses. The changes in hematological profile and blood chemistry in the experimental rabbits were evaluated along with autoantibody responses. Elevations of total white blood cell (WBC), monocyte, eosinophil and basophil counts that developed following immunizations were moderately influenced by litter and presence of the antibody heavy chain allotype VH1a1. Autoantibody development followed a sequential pattern with anti-nuclear antibodies (ANA) followed by anti-dsDNA and subsequently anti-Sm and anti-RNP similar to SLE patients. High autoantibody levels to one autoantigen were not always associated with antibody response to another. Female rabbits had higher prevalence and levels of autoantibodies similar to human SLE. Higher autoantibody levels of anti-dsDNA and -ANA were observed among some full sibs and the presence of high responder ancestors in the pedigree was associated the augmented responses. We observed significant association between highest antibody responses to GR-MAP-8 and highest anti-dsDNA levels. Naturally occurring autoantibodies were found in some pre-immune sera and some unique ANA fluorescent staining patterns within the experimental group were observed. Background immunofluorescence in pre-immune sera, distinct patterns of programmed autoantibody responses unique among individual rabbits may have been modulated by genetic constitution, gender and environmental factors including exposure to antigens. The high incidence and intensity of autoantibody responses among descendants of high responders suggest that there may be an additive mode of inheritance with high heritability. It is conceivable that further rigorous pedigree selection for autoantibody responses could lead to development of rabbit models with spontaneous occurrence of SLE like serology and disease phenotypes.