Systemic lupus erythematosus in southern Spain: a comparative clinical and genetic study between Caucasian and Gypsy patients

Identifying inflammatory phenotypes associated with lung involvement in systemic sclerosis: k-means clustering approach

Objective

to assess the prognostic impact of clusters of hematologic and biochemical indices on interstitial lung disease (ILD) and respiratory damage associated with systemic sclerosis (SSc).

Methods

Design: We conducted a cross-sectional, uncontrolled study. Participants and Settings: a cohort of patients with SSc (2013 ACR/EULAR criteria) were enrolled in the rheumatology unit of a tertiary hospital in southern Spain. Primary and secondary outcome measures: The primary outcomes were the presence of SSc-ILD and respiratory damage, assessed via the Scleroderma Clinical Trials Consortium Damage Index (SCTC-DI). Inflammatory biomarkers, including both CRP and hematological indices, were obtained. Patients were grouped based on inflammatory phenotypes derived from longitudinal CRP averages and through principal component analysis (PCA) with K-means clustering of cross-sectional variables. Multivariate models were constructed to identify factors associated with SSc-ILD and respiratory damage.

Results

Among 83 patients with SSc, 33.7% had ILD, 30.1% had respiratory damage, and 28.9% were receiving immunosuppressive therapy. A persistent inflammatory phenotype during follow-up was associated with non-Caucasian ethnicity (OR 14.0) and SSc-ILD (OR 17.9). Cross-sectional inflammatory clusters were linked to SSc-ILD (OR 12.8) and damage measured by SCTC-DI (OR 1.2). PC-2, derived from CRP-based variables, was a better predictor of SSc-ILD (OR 3.0) than PC-1, which was based on hematological indices (OR 0.5, non-significant), especially in the presence of anti-Scl70+ antibodies (OR 19.1) and immunosuppressants (OR 42.2). The only variables associated with respiratory damage were average CRP during follow-up (OR 1.2), anti-Scl70+ (OR 7.7), and glucocorticoids (OR 0.2).

Conclusion

CRP-based variables seem to be better predictors of SSc-ILD and respiratory damage than hematological indices.

Clustering of systemic lupus erythematosus mortality in southwestern Spain

OBJECTIVE

To analyse time trends in systemic lupus erythematosus (SLE) mortality and explore possible provincial clustering of SLE mortality in Spain (2001-2020).

METHODS

We conducted an ecological study using deaths registered in SLE at the Spanish National Institute of Statistics between 2001 and 2020. Jointpoint regression models have been used to evaluate temporal trends. To analyse the spatial pattern of SLE mortality in men and women in Spain, crude rates, age-standardised mortality rates (ASMRs), smooth relative risk (RR) and posterior probabilities (PP) for RR greater than one for the period 2001-2020 were calculated. The Global Moran I index was used to assess the existence of global spatial autocorrelation. Local indicators of spatial association (LISA) and Kulldorff's spatial scan statistic were used to identify clusters.

RESULTS

Over the 20 years analyzed in this study, the SLE average ASMR for the period was 2.7 for women and 0.7 for men, with a sex ratio (female/male) of 3.8. In men, no province showed a RR>1. Conversely, in women, eight provinces showed values of RR> 1 with a PP greater than 0.8 (Seville, Cadiz, Huelva and Murcia in the south, Barcelona, Zaragoza, Huesca and Leon in the north). In men, neither of the two methods detected a clustering of provinces. However, in women, both methods identified a cluster of provinces located in the southwest of the country (Huelva, Cádiz, Seville and Malaga) as a cluster with significant excess mortality. In the second cluster (centred on the province of Huelva) obtained with the Kulldorff method, two more provinces were added (Badajoz and Cordoba, also located in the southwest).

CONCLUSIONS

We detected a cluster of provinces with an excess risk of female SLE mortality in the southwest of Spain.

Diseases association with the polymorphic major histocompatibility complex class I related chain a: MICA gene

The Major Histocompatibility Complex class I chain-related molecule A (MICA) genes encode a highly polymorphic glycoprotein among the cell surface antigens that trigger an immune response after allograft transplantation. It is encoded by the MICA gene, a member of the glycosylated MIC genes. Discovered in 1994, the MICA gene is located within the MHC class I region. Moreover, its biological function is achieved through the interaction with the NKG2D receptor. Unlike the classical HLA molecules, MICA protein is not associated with β2- microglobulin nor binds peptides. MICA gene expression may result in a cytotoxic response and IFN-γ secretion through the up-regulation by heat shock proteins in response to infection (Human Cytomegalovirus HCMV), mediated by NKG2D-expressing cells. Anti-MICA antibodies were identified as significant risk factors for antibody mediated rejection after being detected in sera of patients with graft rejection. In addition, soluble MICA proteins (sMICA) has been detected in the serum of transplant recipients with cancers. Furthermore, the association of MICA polymorphisms with infectious diseases, various autoimmune diseases, cancer, and allograft rejection or graft-versus-host disease (GVHD) has been studied. Moreover, numerous advanced disease studies centered on MICA polymorphism are independent of HLA association. In this review, we discussed the up-to-date data about MICA and the association of MICA polymorphism with infections, autoimmune diseases, graft-versus-host disease, and cancer.

Human leucocyte antigens profiling in Malay female patients with systemic lupus erythematosus: are we the same or different?

OBJECTIVE

SLE is a heterogeneous autoimmune disease, in terms of clinical presentation, incidence and severity across diverse ethnic populations. We investigated the human leucocyte antigens (HLA) profile (ie, HLA-A, HLA-B and HLA-C, HLA-DRB1, HLA-DQA1, HLA-DQB1, HLA-DPA1 and HLA-DPB1) in Malaysian Malay female patients with SLE and determined the generalisability of the published HLA risk factors across different ethnic populations globally including Malaysia.

METHODS

One hundred Malay female patients with SLE were recruited between January 2016 and October 2017 from a nephrology clinic. All patients were genotyped for HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQA1, HLA-DQB1, HLA-DPA1 and HLA-DPB1 alleles using PCR sequence-specific oligonucleotides method on Luminex platform. A total of 951 HLA genotyped population-based Malay control subjects was used for association testing by means of OR with 95% CIs.

RESULTS

Our findings convincingly validated common associations between HLA-A*11 (OR=1.65, p=3.36×10^-3, corrected P (Pc)=4.03×10^-2) and DQB1*05:01 (OR=1.56, p=2.02×10^-2, Pc=non-significant) and SLE susceptibility in the Malay population. In contrast, DQB1*03:01 (OR=0.51, p=4.06×10^-4, Pc=6.50×10^-3) were associated with decreased risk of SLE in Malay population. Additionally, we also detected novel associations of susceptibility HLA genes (ie, HLA-B*38:02, DPA1*02:02, DPB1*14:01) and protective HLA genes (ie, DPA1*01:03). When comparing the current data with data from previously published studies from Caucasian, African and Asian populations, DRB1*15 alleles, DQB1*03:01 and DQA1*01:02 were corroborated as universal susceptibility and protective genes.

CONCLUSIONS

This study reveals multiple HLA alleles associated with susceptibility and protection against risk of developing SLE in Malay female population with renal disorders. In addition, the published data from different ethnic populations together with our study further support the notion that the genetic effects from association with DRB1*15:01/02, DQB1*03:01 and DQA1*01:02 alleles are generalised to multiple ethnic populations of Caucasian, African and Asian descents.

Clinical, serologic, and immunogenetic characterization (HLA-DRB1) of late-onset lupus erythematosus in a Colombian population

INTRODUCTION

Late-onset systemic lupus erythematosus (SLE) represents a specific subgroup that is defined as onset after 50 years of age. Late-onset lupus may have a different clinical course and serological findings, which may delay diagnosis and timely treatment.

OBJECTIVES

The objective of this paper is to determine the clinical, serologic, and immunogenetic differences among Colombian patients with late-onset SLE versus conventional SLE patients.

METHODOLOGY

This was a cross-sectional study in a Colombian population. Patients and their medical records were analyzed from the services of Rheumatology in Bogotá and met the criteria for SLE, according to the American College of Rheumatology (ACR) revised criteria for the classification of SLE.In a reference group of late-onset SLE patients (98 participants, with an onset after 50 years of age) and a group of conventional SLE patients (72 participants, with an onset of age of 49 years or less), multiple clinical variables (age, clinical criteria for lupus, alopecia, weight loss, fever, Raynaud's phenomenon) and multiple serological variables (blood count, blood chemistry profile, autoantibodies) were analyzed. Additionally, the HLA class II (DRB1) of all the patients was genotyped, including an additional group of patients without the autoimmune disease. Statistical analysis was performed using the STATA 10.0 package.

RESULTS

In the group of late-onset lupus, there was a higher frequency of pleurisy (p = 0.002), pericarditis (p = 0.026), dry symptoms (p = 0.029), lymphopenia (p = 0.007), and higher titers of rheumatoid factor (p = 0.001) compared with the group of conventional SLE. Late-onset SLE patients had a lower seizure frequency (p = 0.019), weight loss (p = 0.009), alopecia (p < 0.001), and Raynaud's phenomenon (p = 0.013) compared to the conventional SLE group. In late-onset SLE, HLA DR17 (DR3) was found more frequently compared with individuals without autoimmune disease (OR 3.81, 95% CI 1.47 to 10.59) (p = 0.0016).

CONCLUSION

In the Colombian SLE population analyzed, there may be a probable association of several clinical and serologic variants, which would allow the differentiation of variables in the presentation of the disease among patients with late-onset SLE vs. conventional SLE.

Value of HLA-DR genotype in systemic lupus erythematosus and lupus nephritis: a meta-analysis

AIM

Human leukocyte antigen (HLA)-DRB1 allele polymorphisms have been reported to be associated with systemic lupus erythematosus (SLE) susceptibility, but the results of these previous studies have been inconsistent. The purpose of the present study was to systematically summarize and explore whether specific HLA-DRB1 alleles confer susceptibility or resistance to SLE and lupus nephritis.

METHODS

This review was guided by the preferred reporting items for systematic reviews and meta-analyses (PRISMA) approach. A comprehensive search was made for articles from PubMed, Medline, Elsevier Science, Springer Link and Cochrane Library database. A total of 25 case-control studies on the relationship between gene polymorphism of HLA-DRB l and SLE were performed and data were analyzed and processed using Review Manager 5.2 and Stata 11.0.

RESULTS

At the allelic level, HLA-DR4, DR11 and DR14 were identified as protective factors for SLE (0.79 [0.69,0.91], P < 0.001; 0.72 [0.60, 0.85], P < 0.0001; 0.47 [0.59, 0.95], P < 0.05, respectively). HLA-DR3, DR9, DR15 were potent risk factors for SLE (1.88 [1.58, 2.23], P < 0.001; 1.24 [1.07, 1.45], P < 0.05; 1.25 [1.10, 1.43], P < 0.001, respectively). However, HLA-DR8 was not statistically significant between the SLE group and control group (OR, 1.11 [0.96, 1.30], P > 0.05). DR4 and 11 (OR, 0.55 [0.39, 0.79], P < 0.01; 0.60 [0.37, 0.96], P < 0.05, respectively) conferred a significant protective effect for lupus nephritis. DR3 and DR15 (OR, 2.00 [1.49, 2.70], P < 0.05; 1.60 [1.21, 2.12], P < 0.001, respectively) were at a high risk of developing lupus nephritis. HLA-DR8, DR9 and DR14 (OR, 1.47 [0.9, 2.33], P > 0.05; 0.90 [0.64, 1.27], P > 0.05; 0.61 [0.36, 1.03], P > 0.05, respectively) were not statistically significant between the lupus nephritis and control groups.

CONCLUSIONS

The HLA-DR4, DR11, DR14 alleles might be protective factors for SLE and HLA-DR3, DR9, DR15 were potent risk factors. In addition, HLA-DR4 and DR11 alleles might be protective factors for lupus nephritis and DR3 and DR15 suggest a risk role. These results proved that HLA-DR3, DR15, DR4 and DR11 might be identified as predictors for lupus nephritis and SLE.

Relation between HLA typing and clinical presentations in Systemic Lupus Erythematosus patients in Al-Qassim region, Saudi Arabia

BACKGROUND

Systemic lupus erythematosus (SLE) is a disease with diverse clinical presentations due to interaction between genetic and environmental factors. SLE is associated worldwide with polymorphisms at various loci, including the major histocompatibility complex (MHC), although inconsistencies exist among these studies.

AIMS

This study was carried out to investigate, the association of HLA-DRB1, DRB3, DRB4, DRB5, and DQB1 alleles in SLE patients and clinical presentations at Qassim, Saudi Arabia.

METHODS

Fifty one patients with SLE-84.3% of whom had kidney involvement were studied in a case control study for HLA-DRB1, DRB3, DRB4, DRB5, and DQB1.

RESULTS

It was found that DRB3 is a protective gene among Saudi's against SLE, HLA DRB3, HLA DRB1*11 frequency was increased in patients with serositis with a p value of (0.004), (0.047) respectively, increased frequency of HLA DQB1*3 among SLE patients with skin manifestations with a p value of (0.041), the frequency of HLA DRB1*15 alleles was increased among SLE patients with nephritis with a p value of (0.029), the frequency of HLA DRB1*11 among those with hematological manifestations with a p value of (0.03) and the frequency DRB1*10 was found to be increased among SLE patients with neurological manifestations with a p value of (0.002).

CONCLUSION

In contradistinction to what have been found among other populations DRB3 is a protective gene among Saudi's against SLE. No evidence for a role of the HLA-DRB1, DRB4, DRB5, DQB1 alleles. There was an increased HLA DRB3 frequency with serositis, DQB1*3 skin manifestations, HLA DRB1*15 with nephritis, DRB1*10 with hematological manifestations and DRB1*11 with neurological manifestations.

Late-onset systemic lupus erythematosus in Northwestern Spain: differences with early-onset systemic lupus erythematosus and literature review

To further investigate into the epidaemiology of systemic lupus erythematosus (SLE) in Southern Europe, we have assessed the incidence, clinical spectrum and survival of patients diagnosed with late-onset SLE (age ≥ 50 years) according to the 1982 American College of Rheumatology (ACR) classification criteria at the single hospital for a well-defined population of Lugo, Northwestern (NW) Spain. Between January 1987 and December 2006, 51 (39.3%) of the 150 patients diagnosed as having SLE fulfilled definitions for late-onset SLE. The predominance of women among late-onset SLE (4:1) was reduced when compared with that observed in early-onset SLE (7:1). However, the incidence of late-onset SLE was significantly higher in women (4.2 [95% confidence interval (CI): 3.1–5.6] per 100,000 population) than in men (1.3 [95% CI: 0.6–2.2] per 100,000 population) ( p < 0.001). As observed in early-onset SLE, the most frequent clinical manifestation in patients with late-onset SLE was arthritis (71.2%). Renal disease was less common in late-onset SLE (13.5%) than in early-onset SLE (26.4%); p = 0.07). In contrast, secondary Sjögren syndrome was more commonly found in the older age-group (27.1% versus 12.1%; p = 0.03). A non-significantly increased incidence of serositis was also observed in late-onset SLE patients (33.9% versus 22.0%; p = 0.13). Hypocomplementaemia (72.9% versus 91.2%) and positive results for anti-DNA and anti-Sm (49.2% and 6.8% versus 68.1% and 23.1, respectively) were significantly less common in late-onset SLE patients than in early-onset SLE. The probability of survival was reduced in late-onset SLE ( p < 0.001). With respect to this, the 10-year and 15-year survival probability were 74.9 % and 63.3% in the late-onset SLE group and 96.3% and 91.0% in patients with early-onset SLE, respectively. In conclusion, our results confirm that in NW Spain SLE is not uncommon in individuals 50 years and older. In keeping with earlier studies, late-onset SLE patients from NW Spain have some clinical and laboratory differences with respect to those individuals with early-onset SLE. Our data support the claim of a reduced probability of survival in the older age-group of SLE patients.

Roma ethnicity and clinical outcomes in kidney transplant recipients

BACKGROUND

Racial and ethnic disparities among North American patients with chronic kidney disease have received significant attention. In contrast, little is known about health-related outcomes of patients with end-stage renal disease among the Roma minority, also known as gypsies, compared to Caucasian individuals. We prospectively assessed the association between Roma ethnicity and long-term clinical outcomes in kidney transplant recipients.

METHODS

In a prevalent cohort of renal transplant recipients, followed up over a median of 94 months, we prospectively collected socio-demographic, medical (and transplant related) characteristics and laboratory data at baseline from 60 Roma and 1,003 Caucasian patients (mean age 45 (SD = 11) and 49 (SD = 13) years, 33 and 41% women, 18 and 17% with diabetes mellitus, respectively). Survival analyses examined the associations between Roma ethnicity and all-cause mortality and death-censored graft loss or death with functioning renal allograft.

RESULTS

During the follow-up period, 341 patients (32%) died. Two-hundred eighty (26%) patients died with a functioning graft and 201 patients (19%) returned to dialysis. After multivariable adjustments, Roma ethnicity was associated with 77% higher risk of all-cause mortality (Hazard Ratio (HR): 1.77; 95% confidence interval (CI): 1.02, 3.07), two times higher risk of mortality with functioning graft (2.04 [1.17-3.55]) and 77% higher risk of graft loss (1.77 [1.01-3.13]), respectively.

CONCLUSIONS

Roma ethnicity is independently associated with increased mortality risk and worse graft outcome in kidney transplant recipients. Further studies should identify the factors contributing to worse outcomes among Roma patients.

Systemic lupus erythematosus in northwestern Spain: a 20-year epidemiologic study

To further investigate the epidemiology of systemic lupus erythematosus (SLE) in southern Europe, we assessed the incidence, prevalence, clinical spectrum of the disease, flares, and survival of patients diagnosed with SLE in the Lugo region of northwestern Spain. Between January 1987 and December 2006, 150 Lugo residents were diagnosed as having SLE according to the 1982 American College of Rheumatology criteria for the classification of SLE. Women outnumbered men (127 [84.7%] vs. 23 [15.3%]). The mean age at the time of disease diagnosis was 46.1 ± 19.6 years. The mean follow-up from the time of disease diagnosis was 7.8 ± 4.5 years. The age- and sex-adjusted annual incidence rate over the 20-year study period was 3.6 (95% confidence interval [CI], 3.0-4.2) per 100,000 population aged 15 years and older. The overall annual incidence rate over the 20-year study period in women (5.9/100,000 population aged ≥ 15 yr; 95% CI, 4.9-7.0) was higher than in men (1.1/100,000 population aged ≥ 15 yr; 95% CI, 0.7-1.7) (p < 0.001). By December 31, 2006, the overall age-adjusted SLE prevalence in the Lugo region for patients who fulfilled at least 4 of 1982 American College of Rheumatology criteria was 17.5 per 100,000 population aged 15 years and older (95% CI, 12.6-24.1). Prevalence in women (29.2/100,000 population aged ≥ 15 yr; 95% CI, 20.0-40.7) was higher than in men (5.8/100,000 population aged ≥ 15 yr; 95% CI, 2.0-12.0). The most frequent clinical manifestation was arthritis. As reported in population-based studies on SLE patients of European descent, renal disease was observed in only 27.3% of the patients. The rate of flares was 0.084/year. A younger age and the presence of nephritis at the time of disease diagnosis were associated with the development of flares during the follow-up of Lugo patients. Compared with the general population the probability of survival in patients with SLE was significantly reduced (p = 0.04). In conclusion, the present study establishes a baseline estimate of the incidence and clinical spectrum of SLE in northwestern Spain. According to our results, the incidence of SLE in northwestern Spain is slightly higher than that reported in most European regions. Patients with SLE from northwestern Spain have a later average age onset and a lower frequency of nephritis than in the African-American population. However, our data show a reduced probability of survival in Spanish patients with SLE.

HLA association in SLE patients from Lahore-Pakistan

The first genetic factors to be identified as important in the pathogenesis of Systemic lupus erythematosus (SLE) were those of the major histocompatibility complex (MHC) on chromosome 6. It is now widely accepted that MHC genes constitute a part of the genetic susceptibility to SLE. The study population comprised 61 SLE patients fulfilling at least four of the American college of Rheumatology criteria for SLE and 61 healthy blood donors as controls. SLE female versus male ratio was approximately 9:1. Mean age at diagnosis was 30.35 ± 1.687 (12-68 years). DNA-based HLA Typing for HLA-A, HLA-B, and HLA-DRB1 was carried out by Polymerase chain reaction with sequence specific primers using genomic DNA obtained from blood samples. A total of 22 alleles have been studied at locus A, 37 alleles at locus B and 17 DRB1 alleles. The allelic frequencies of HLA-A, HLA-B, and HLA-DRB1 antigens in SLE patients from Pakistan were compared with the controls. A significant increase was observed in the frequency of HLA-A*01, A*03, A*11, A*23, A*26 A*69, HLA-B*27, B*40, B*49, B*51, B*52, B*53, B*54, B*95, HLA-DRBI*01, DRBI*03, DRBI*11, DRBI*14 among SLE patients indicating a positive association of these alleles with SLE. HLA-A*24, A*29, A*31, A*34, A*68, A*92, HLA-B*18, HLA-DRB1*12, were found to be decreased in the patient group as compared to controls indicating a negative association of these alleles with SLE. Thus from this study we can conclude that SLE is associated with certain MHC alleles in Pakistani population.

The geoepidemiology of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with manifold clinical manifestations and immunological abnormalities, affecting primarily women. Although accurate current data on its incidence and prevalence are largely lacking, there are numerous indications that SLE is far less common in Europeans and their descendants compared to all other ethnicities. The clinical manifestations of the disease show geographic or ethnic variation, generally being less severe in patients of European ancestry than in African, Asian, certain "Hispanic" or mestizo, and various indigenous populations. In particular, renal involvement is far more common in non-European patients. Genetic as well as environmental, sociodemographic and sociocultural factors are likely to contribute to the differences in the incidence and clinical expression of SLE.

Impact of immigration on the clinical expression of systemic lupus erythematosus: a comparative study of Hispanic patients residing in the USA and Mexico

OBJECTIVE

To compare the socio-economic characteristics, clinical features and health-related quality of life in Hispanic SLE patients residing in Mexico and in the Southwest USA (Mexican and Texan, herein).

METHODS

Mexican and Texan SLE patients (fulfilling ACR criteria) participating in separate longitudinal outcome studies were evaluated. Texan patients were randomly chosen to match total disease duration with the Mexican patients. Cross-sectional data for the Mexican patients were obtained by a US-trained investigator who had previously participated in data collection for the cohort to which the Texan patients belonged. Socio-economic and -demographic characteristics, clinical characteristics, disease activity (with SLAM-Revised), damage accrual (with SLICC/ACR Damage Index) and self-reported function (with Short Form-36) were compared between the two groups.

RESULTS

Seventy Mexican patients were matched with either one or two Texan patients (n = 94) for a total of 164 patients. Mexican patients were younger. In age-adjusted analyses, the Mexican patients were more educated, had better health-related quality of life and overall less systemic SLE manifestations. Mexican patients were exposed more frequently to AZA.

CONCLUSIONS

Texan patients had more severe disease than the Mexican patients. In multivariable analyses, Texan Hispanic ethnicity was significantly associated with high disease activity, but significance was not reached for damage. The discrepant findings observed between these two Hispanic groups of SLE patients may reflect socio-economic or biological factors. Given the global phenomenon of immigration, rheumatologists should be aware of the overall course and outcome of immigrant SLE patients if undesirable outcomes are to be prevented.

No primary association of MICA polymorphism with systemic lupus erythematosus

OBJECTIVE

To replicate the described association between MHC class I chain-related A (MICA) gene polymorphism and susceptibility to systemic lupus erythematosus (SLE).

METHODS

MICA transmembrane microsatellite polymorphism was genotyped using a polymerase chain reaction (PCR)-based method. Genotyping of HLA-B* and DRB1* was performed using PCR and detection with a reverse sequence-specific oligonucleotide (SSO) probe system. Combined data for these three loci (HLA-B*, DRB1* and MICA) were obtained from a total of 333 patients and 361 healthy controls.

RESULTS

Significant association with B*08 [P < 10(-7), odds ratio (OR) 3.17, 95% confidence interval (CI) 2.02-5.00], DRB1*0301 (P < 10(-7), OR 2.07, 95% CI 1.59-2.68) and MICA5.1 (P = 0.01, OR 1.23, 95% CI 1.04-1.46) was observed. The combinations DRB1*0301-MICA5.1-B8 and HLA-DRB1*0301-B*08-positive and MICA5-1-negative were more frequent among SLE patients (11.4 vs 3.3% in healthy controls, P = 3.9 x 10(-5), OR 3.76, 95% CI 1.85-7.73, and 6.9 vs 1.7%, P = 0.0007, OR 4.32, 95% CI 1.68-13.10, respectively). Additionally, individuals who were HLA-DRB1*0301-B*08-negative and MICA5-1-positive were less frequent among patients (22.2 vs 31.3% in healthy controls, P = 0.007, OR 0.63, 95% CI 0.44-0.89) and the magnitude of the OR was similar to that obtained in individuals negative for all the three factors (OR 0.69, 95% CI 050-0.94). Further analysis performed to detect independent association strongly suggested that the association between MICA5.1 and SLE is secondary to the linkage disequilibrium of this allele with B*08.

CONCLUSIONS

Our results do not support an independent association of MICA gene polymorphism with susceptibility to SLE.