Prevalence of HLA-B27 in Patients with Ankylosing Spondylitis in Qatar

Prevalence of HLA B27 in Patients Diagnosed with Ankylosing Spondylitis (AS) in Diyarbakır, Southeastern Region of Turkey

AIM

The research to be conducted on human leukocyte antigen (HLA)-B27 in patients diagnosed with ankylosing spondylitis (AS) in Diyarbakır between 2019-2021 is to contribute to the understanding of the prevalence and effect of this genetic marker in the local population. As a researcher working on HLA-B27 and AS, our focus is to research the following. HLA-B27 Prevalence: To determine the prevalence of HLA-B27 in patients diagnosed with AS during the specified period in Diyarbakır. This information can provide insight into the genetic factors associated with the disease in the local population. Disease Severity: Investigate the relationship between HLA-B27 positivity and severity of AS symptoms. To examine factors such as disease progression, pain levels, functional impairment, and quality of life in HLA-B27 positive patients compared to HLA-B27 negative patients. By Genetic Associations: To enable the discovery of potential genetic relationships between HLA-B27 and other genetic markers known to be associated with AS. To investigate whether there are any specific genetic variants associated with HLA-B27 that contribute to disease susceptibility or severity. Researchers: We recommend considering the following approaches to generate knowledge on this topic globally: Literature Review: Conducting a comprehensive review of the available scientific literature on HLA-B27 and AS. It is to describe relevant studies conducted globally and summarize their findings to provide a broader understanding of the subject. Collaboration and Data Sharing: To encourage cooperation with researchers from other regions or countries doing similar studies on HLA-B27 and ASs. By sharing our data and collaborating on analysis, we can improve the global perspective and generalizability of your findings. International Conferences and Journals: Presenting our research findings at international conferences focusing on rheumatology, genetics or related fields. To disseminate our findings globally is to submit your research articles to reputable journals specializing in AS or genetic studies. Online Platforms: Using online platforms such as Researchgate.net, academia.edu or social media networks to share our research findings, connect with other researchers in the field and participate in discussions on a global scale. By using these fields, it is possible to contribute to the global knowledge and understanding of the relationship between HLA-B27 and AS. It is also to obtain insights from studies carried out in other regions.

MATERIALS AND METHODS

198 (104 male and 94 female) patients who applied to Dicle University Faculty of Medicine Physical Therapy and Rehabilitation Clinic with AS symptoms between 2019-2021 and were referred to Dicle University Medical Biology and Genetics Department for evaluation. HLA-B27 positivity was included in our study as a case group. As the control group, 50 people (25 males, 25 females) were selected among the unrelated people who applied to our laboratory to be a bone marrow donor. In both groups, DNA isolation was performed from peripheral blood using the salt precipitation method. Rotar Gene Q device was used for real-time PCR analysis. As a statistical method in analysis; The prevalences of the variables of interest were calculated. The lower and upper limits of 95% were determined as the confidence interval. According to the presence of HLA 27 positivity, the mean of ESR, CRP, and age variables were compared. Mann-Whitney U test was used due to the small number of subjects. Also, correlations between ESR and CRP were calculated. Spearman rho correlation statistics were used as a statistical method. Analyzed.

RESULT

Radiological examinations and laboratory tests were performed on 198 patients with suspicion AS and 50 healthy control group of 248 subjects. The prevalence of those with a definite diagnosis of AS was calculated as statistical analysis recalculated 20.16 (95% CI: 0.76-0.9552). The prevalence of HLA-B27 in 50 patients diagnosed with AS as a result of radiological examinations and laboratory tests was calculated as 92%.

CONCLUSION

Our study is the first study covering the province of Diyarbakır in the Southeastern Anatolia Region, which we think will contribute to the literature in the evaluation of HLA-B27 positivity in AS patients. The prevalence of HLA-B27 in our region is higher than the prevalence in Turkey.

Assessment of Circulating lncRNA H19 in Ankylosing Spondylitis Patients and Its Correlation with Disease Activity

Ankylosing spondylitis (AS) is a chronic inflammatory disease that results in severe pain and stiffness in the joints. The causes and pathophysiology of AS are still largely unknown. The lncRNA H19 plays key roles in the pathogenesis of AS by mediating inflammatory progression by acting in the axis of IL-17A/IL-23. The aims of this study were determining the role of lncRNA H19 in AS and assessing its clinical correlation. A case-control study was conducted and qRT-PCR was utilized to measure H19 expression. Comparing AS cases to healthy controls, it was found that H19 expression was significantly upregulated. For AS prediction, H19 demonstrated a 81.1% sensitivity, 100% specificity, and 90.6% diagnostic accuracy at a lncRNA H19 expression value of 1.41. lncRNA H19 had a significantly positive correlation with AS activity, MRI results, and inflammatory markers. lncRNA H19 seemed to be an independent predictor of AS (adjusted OR of 211 (95% CI: 4.7-939; p = 0.025)). After 3 months of clinical follow-up, seventeen patients (32.1%) showed minimal clinical improvement and fifteen patients (28.3%) showed major improvement. AS activity scores were significantly decreased in patients with high H19 expression. A significantly elevated lncRNA H19 expression was observed in AS cases compared with that in healthy controls. These results suggest that upregulation of lncRNA H19 expression may be involved in the pathogenesis of AS. The expression of the lncRNA H19 is related to the duration and activity of the disease. LncRNA H19 expression seems to be an independent predictor of AS.

The treatment journey for patients with axial spondyloarthritis in North Africa and the Middle East: From diagnosis to management

The management of axial spondyloarthritis (axSpA) is challenging worldwide, and the particular challenges shared by North Africa and the Middle East are mainly related to early diagnosis and standardized management. We believe there are several reasons for these challenges, including: (a) limited awareness of the disease manifestations and prevalence in the region among physicians; (b) the concept of nonradiographic axSpA, while accepted with some difficulty by the rheumatology community, may not be well understood by the referring primary care physicians; (c) access to, and training in magnetic resonance imaging varies greatly between countries in the North Africa and Middle East region, and this may have a large impact on early diagnosis; (d) country‐specific treatment guidelines are unavailable; and (e) economic and cultural factors influence patients’ attempts to seek and continue treatment. In this review, we will discuss the prevalence of axSpA in North Africa and the Middle East, as well as the challenges to diagnose and treat patients in this region. As rheumatologists practicing in North Africa and the Middle East, we also provide suggestions to assist physicians, other healthcare professionals, and researchers in facilitating early, accurate diagnosis and treatment of axSpA.

Taiwan Rheumatology Association consensus recommendations for the management of axial spondyloarthritis

Aim

To establish guidelines for the clinical management of axial spondyloarthritis that take into account local issues and clinical practice concerns for Taiwan.

Method

Overarching principles and recommendations were established by consensus among a panel of rheumatology and rehabilitation experts, based on analysis of the most up‐to‐date clinical evidence and the clinical experience of panelists. All Overarching Principles and Recommendations were graded according to the standards developed by the Oxford Centre for Evidence Based Medicine, and further evaluated and modified using the Delphi method.

Results

The guidelines specifically address issues such as local medical considerations, National Health Insurance reimbursement, and management of extra‐articular manifestations.

Conclusion

It is hoped that this will help to optimize clinical management outcomes for axial spondyloarthritis in Taiwan.

Association study of copy number variants in CCL3L1, FCGR3A and FCGR3B genes with risk of ankylosing spondylitis in a West Algerian population

Numerous single nucleotide polymorphisms (SNPs) were explored in the Algerian population to evaluate associated ankylosing spondylitis (AS) genetic risk factors, but no study has identified the impact of copy number variations (CNVs). The aim of the study was to determine whether CNVs of CCL3L1, FCGR3A and FCGR3B genes were also associated with the susceptibility of AS disease in Algerian population. The data set of the current study is composed of 81 patients with AS and 119 healthy controls. All samples were genotyped by digital droplet PCR (ddPCR). Chi-square test and OR calculation were used to evaluate association between CNVs and AS and the risk associated with copy numbers (CN). In results, FCGR3A CN less than two copies (<2) was significantly increased in spondylitis patients (p = .0001, OR = 7.74 [2.32-25.74]). Additionally, FCGR3A CN < 2 copies association was present only in HLA-B27 (-) patients. We have concluded that FCGR3A deletions have an independent effect on AS regarding HLA-B27 status. This is the first study that investigated the CCL3L1 CNVs in relation to AS risk disease. It reveals that CCL3L1 and FCGR3B CNVs may not be involved in susceptibility to AS risk in the Algerian population.

The Early Phases of Ankylosing Spondylitis: Emerging Insights From Clinical and Basic Science

In our paper, we discuss how the early phases of ankylosing spondylitis (AS) are linked to peri-firbocartilagenous osteitis in the sacroiliac joint and entheseal bone related anchoring sites. This skeletal proclivity is linked to an abnormal immunological response to skeletal biomechanical stress and associated microdamage. A key event in the early stages of AS appears to be the association with subclinical Crohn's-like colitis with this gut inflammation being pivotal to the osteitis reaction. Whether this osteitis is consequent to non-specific intestinal innate immune activation or adaptive immune responses against specific microbiotal or self-antigens is unknown. Recurrent iritis is an HLA-B27 associated feature that may predate AS and pursues a course independent of joint involvement, and points toward the pivotal role of organ specific immunology over generalized systemic immune responses in disease expression. Human genetics and animal model studies strongly incriminate the IL23/17 axis and TNF-α in disease pathogenesis. Preliminary work shows a strong convergence of innate immune cells including type 3 innate lymphoid-cells (ILC3) and γδ T-cells in skin, gut, entheseal, and eye inflammation. Despite the HLA-B27 association, the role of adaptive immunity, especially CD8+ T-cells mediated responses remains unproven and alternative theories have been proposed. The emerging non-dependence of axial inflammation on IL-23 but dependence on IL-17A is an unexpected new twist that awaits full explanation. In this mini-review, we discuss the key events in the early stages of human AS from clinical and basic science aspects, which could be crucial for attempted disease prevention studies in at risk subjects.

Diagnostic Performance of Red Cell Distribution Width in Adult Iraqi Patients with Ankylosing Spondylitis

BACKGROUND

Ankylosing spondylitis (AS) is a chronic, progressive inflammatory rheumatic disease that leads to structural damage, functional impairment, and decrease in the quality of life. Red cell distribution width (RDW) is a part of the complete blood count (CBC) and estimates erythrocyte variability.

OBJECTIVE

To analyse RDW in patients with AS and to evaluate the relationships with acute phase reactants (APRs) and disease activity index.

PATIENTS AND METHODS

A total of 100 patients with AS (78 males and 22 females) were diagnosed according to the modified New York classification criteria for AS and 146 (99 males: 47 females) healthy individuals matched in age and sex as controls enrolled in the study. Demographic data, disease activity scores using Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), medical history, C-reactive protein (CRP), erythrocytes sedimentation rate (ESR), and complete blood count (CBC) were measured.

RESULTS

The mean age for patients and controls was 38.0 ± 9.0 and 35.8 ± 9.0 years, respectively (p=0.057). RDW was significantly higher in patients with AS compared with controls (14.133 ± 1.613 versus 12.299 ± 1.031, p < 0.001). There was a direct correlation of RDW with both ESR and CRP (P < 0.001); RDW had r=0.38 for C-reactive protein (CRP) and r=0.413 for ESR. Also BASDAI was directly correlated with RDW (r=0.326 p<0.001). RDW was a valid measure to differentiate between patients with AS and controls (AUC=0,84, p<0.001) and at optimum cut-off value>13% has highest accuracy (78.9%) with very good sensitivity test (81%) and NPV (85.6%) as well as good specificity (77.4%) and PPV (71.1%).

CONCLUSION

RDW was higher in AS patients compared with controls and was directly correlated with ESR, CRP, and BASDAI. RDW was a valid simple measure with good accuracy to differentiate between patients with AS and controls.

Association of the HLA-B27 antigen and the CTLA4 gene CT60/rs3087243 polymorphism with ankylosing spondylitis in Algerian population: A case-control study

Ankylosing spondylitis (AS) is a complex inflammatory disease that represents a major health problem both in Algeria and worldwide. Several lines of evidence support that genetic risk factors play a role in AS etiology and the CTLA4 gene has attracted a considerable attention. In this study, we were interested in evaluating the HLA-B27 frequency and in exploring the CTLA4 gene in a sample of the North African population. The dataset of the current study is composed of 81 patients with AS and 123 healthy controls. All samples were genotyped by TaqMan^® allelic discrimination assay. The genetic risk of the HLA-B27 specificity and the CTLA4/CT60 polymorphism were assessed by odds ratios (OR) with 95% confidence intervals (CI). High spondylitis risk was detected for HLA-B27 allele (OR= 14.62, p = 10^-6 ) in addition to a significant association of the CT60*G allele (OR= 1.89, p = .002). After gender and age stratifications, the association of the CT60*G allele was still significant in females sample (OR= 2.10, p = .001) and when age up to 30 years (OR = 2.21, p = .008). Interestingly, the CT60*G allele revealed an increased spondylitis risk in the B27 negative group (OR= 2.81, p = .006). The present work showed in West Algerian population that the HLA-B27 antigen and the variation in the CTLA4 3'UTR region played an important role in the ankylosing spondylitis susceptibility. The heterogeneity of this disease is deduced by genetic difference found between B27+ and B27- groups.

Interethnic Variations and Clinical Features of Spondyloarthropathies in a Middle Eastern Country

Objectives

The study aimed to demonstrate the interethnic differences and clinical features of Spondyloarthropathy(SpA) patients in a diverse Middle Eastern Country.

Methods

A retrospective review of medical records to collect the required data was conducted for SpA patients at two study institutions in the United Arab Emirates.

Results

Of 141 SpA patients found, 88 AS(Ankylosing Spondylitis) patients and 53 'other SpA' patients were identified. Males constituted 81% of AS and 55% of 'other SpA' patients. Patients with AS and 'other SpA' had a mean age of symptom onset of 28 and 34 years, respectively.49% and 40% of AS and 'other SpA' patients had a history of Anti-TNF therapy usage. Enthesitis and Uveitis were noted in 16% and 18% of AS patients whilst 53% and 11% in 'other SpA' patients, respectively.Caucasian, Indian Subcontinent and Arabs constituted 93% of our cohort. Mean age of onset of symptoms in the Indian Subcontinent 'other SpA' group was much greater than the other two ethnicities. Duration of symptoms to diagnosis was 3.5 and 4 years in AS and other SpA patients' respectively. HLA-B27 positivity was found in 53%, 80% and 93% of Arab, Indian Subcontinent and Caucasian AS patients, respectively, whilst seen in 50%, 25% and 33% of the same respective ethnicties in 'other SpA' patients.

Conclusion

This study on 141 patients is the largest to analyse inter-ethnic variations in SpA patients in the region. Our cohort shows a short delay in diagnosis with a relatively higher Anti-TNF usage.

Inflammatory back pain and associated disease conditions among patients with chronic low back pain in Bangladesh

AIM

Inflammatory back pain (IBP) is the earliest symptom of axial and other forms of spondyloarthritis (SpA). However, there are no published data on prevalence of IBP among patients suffering from chronic low back pain (CLBP) in Bangladesh. In this study, we estimated the prevalence of IBP and the subtypes of SpA in a tertiary hospital in Bangladesh.

METHODS

This 1 year cross-sectional study was conducted among 240 CLBP patients in a rheumatology outpatient clinic. Assessment of Spondyloarthritis International Society classification criteria of IBP and predefined recognized classification criteria were followed to define different subtypes of SpA. Means and standard deviations were reported for continuous variables. Descriptive and bi-variate analyses were accordingly performed.

RESULTS

Of 240 CLBP patients, 60 (25%) had IBP and 180 (75%) had mechanical back pain (MBP). Among the 60 IBP patients, 52 (86.6%) had predominantly axial SpA (axSpA) and eight (13.4%) had predominantly peripheral spondyloarthritis. In the axSpA group, 49 (94.2%) had radiographic axSpA (rd-axSpA) also known as AS and three (5.8%) had non-radiographic axSpA (nr-axspA). AxSpA patients could be divided into eight (15.35%) with psoriasis, two (3.8%) with reactive arthritis and one patient (1.9%) had arthritis associated with inflammatory bowel disease. Fifty (83.3%) IBP and 73 (40.6%) MBP patients had age at onset of back pain < 40 years. Forty-two (70%) of the IBP and 100 (55.6%) of the MBP patients had normal body mass index. All these differences were statistically significant (P ≤ 0.0001).

CONCLUSIONS

Inflammatory back pain is common among patients presenting with CLBP. The commonest cause of IBP is AS, followed by PsA and nr-axSpA.

MEFV M694V mutation has a role in susceptibility to ankylosing spondylitis: A meta-analysis

OBJECTIVE

The aim of the current study was to determine the contributions of several common mutations in the Mediterranean fever (MEFV) gene, namely, E148Q, M680I, M694V and V726A, to ankylosing spondylitis (AS) susceptibility.

METHODS

Two investigators independently searched the literature regarding the association of MEFV with AS in the PubMed, EMBASE, Web of Science, and Scopus databases. They independently selected eligible articles and then extracted data from the included studies. The associations between MEFV mutations and AS risk were assessed with odds ratios (ORs) and 95% confidence intervals (95% CI). Further analyses were conducted with STATA 12.0 software (Stata Corp.; College Station, Texas, USA).

RESULTS

Four mutations (E148Q, M680I, M694V and V726A) were genotyped in 869 AS cases and 879 controls from the 8 eligible studies. Of the four mutations, M694V (pooled OR: 3.330, 95% CI: 2.129-5.208) was found to be associated with AS through overall analysis. However, the other mutations demonstrated no relation with AS (pooled ORs: 1.295, 1.258, 1.778; 95% CI: 0.886-1.891, 0.688-2.298 and 0.938-3.371). No significant publication bias was discovered in the meta-analysis.

CONCLUSIONS

The present study indicates that the MEFV M694V mutation may contribute to the pathogenesis of AS. The associations between the other mutations and AS need to be validated with more relevant and well-designed studies.

HLA B27 antigen in Middle Eastern and Arab countries: systematic review of the strength of association with axial spondyloarthritis and methodological gaps

Background

Axial spondyloarthritis (AxSpA) is a relatively frequent and debilitating disease, with a prevalence ranging from 0.1 to 2% in the Caucasian population. Current Assessment of Spondyloarthritis International Society (ASAS) classification criteria of AxSpA rely either on sacroiliitis on imaging plus one SpA feature or positive HLAB27 antigen plus two SpA features, in a patient with chronic low back pain and age at onset of less than 45 years. Therefore, HLA-B27 is a central feature in SpA classification and plays a pivotal role in referral strategies and early diagnosis. The primary objective of the study is to review the prevalence of HLA-B27 in normal and AxSpA populations in Middle Eastern and Arab Countries and to assess the strength of association between HLA-B27 antigen and AxSpA. The secondary objective is to identify the gaps in the methodology of the studies and suggest a framework for future research.

Methods

Studies were included in the analysis if they reported prevalence of HLA-B27 in AxSpA and/or general population and if they covered geographical location in the Middle East or Arab countries in the Mediterranean basin. Odds ratios (OR) were calculated for each country, as a measure of the strength of association between HLA-B27 and AxSpA, compared to the normal population, using the two-by-two frequency table. Available data from the literature were analyzed according to the following quality indicators: sample size, method of HLA-B27 testing, presence of control group and external validity.

Results

Twenty-seven studies were analyzed. HLAB27 prevalence in the normal population ranged from 0.3% (Oman) to 6.8% (Turkey). HLA-B27 prevalence in AxSpA ranged from 26.2% (Lebanon) to 91% (Turkey). HLA-B27 prevalence in all SpA ranged from 13.87% (Lebanon) to 69.43% (Kuwait). Peripheral SpA was less associated with HLA-B27 than AxSpA, indicating the need of differentiating between the two entities when calculating prevalence. When available (8 studies), the OR ranged from 21.63 (Morocco) to 105.6 (Syria). The high heterogeneity between the results can be due to differences in methodology: study sample size, different classification criteria, absence of control groups, HLA-B27 testing method.

Conclusions

The prevalence of HLA-B27 in the normal population is significantly lower in the Middle Eastern and Arab countries than in Western Countries. However, HLA-B27 testing can be useful for AxSpA positive diagnosis, given the high OR. Heterogeneity between countries may be due to methodological differences.

Prevalence of HLA-B27 in the general population and in patients with axial spondyloarthritis in Saudi Arabia

The prevalence of HLA-B27 in the general population and in axial spondyloarthritis (axSpA) patients in Saudi Arabia is unknown. The aim of this study was to evaluate the prevalence of HLA-B27 in these two populations and describe the delay in diagnosis of axSpA patients. The prevalence of HLA-B27 in the general population was evaluated using cord blood and healthy organ transplant donor databases. Data from patients with axSpA were collected retrospectively from five centers. Ankylosing spondylitis (AS) was diagnosed based on a positive X-ray, as evaluated by two independent readers. Patients with inflammatory bowel disease and psoriasis were excluded. A total of 134 axSpA patients were included, of whom 107 (79.9%) had AS, and most (67.2%) were males. HLA-B27 was positive in 60.4, 69, and 25.9% of patients with axSpA, AS, and non-radiographic axSpA (nr-axSpA), respectively. The median and interquartile range (IQR) ages at symptom onset and disease diagnosis were 26 (20-33) and 30 (25-38) years, respectively. The median delay to diagnosis was 3 (1-6) years. There was a negative correlation between the time of onset of symptoms and the delay in diagnosis (r = -0.587). Male gender and HLA-B27 positivity were associated with a younger age at symptom onset/diagnosis (p < 0.05). HLA-B27 was positive in 82/3332 (2.5%) and 27/1164 (2.3%) individuals in the cord blood and healthy organ transplant donor databases, respectively. The prevalence of HLA-B27 is lower in the general Saudi population and in axSpA patients compared to Caucasians, thus, limiting its utility as a diagnostic criterion.

Association of rs11209032 and rs1004819 Polymorphisms in Interleukin-23 Receptor Gene With Ankylosing Spondylitis

Objectives

This study aims to investigate the distribution of human leukocyte antigen B27 (HLA-B27) alleles (+/-) and interleukin-23 receptor (IL-23R) gene rs11209032 and rs1004819 polymorphisms among ankylosing spondylitis (AS) patients in a Turkish cohort.

Patients and methods

The study sample comprised 106 AS patients (89 males, 18 females; mean age 38.9±10 years; range 19 to 65 years) and 82 healthy controls (70 males, 12 females; mean age 32.15±7.07 years; range 19 to 51 years). Distribution of HLA-B27 alleles (+)/(-) in AS patients were observed by reverse hybridization technique. Genotyping of IL-23R rs11209032 and rs1004819 polymorphisms of AS patients and healthy controls were performed by real time polymerase chain reaction.

Results

Of the AS patients, 69 (65.1%) were HLA-B27 positive. Distribution of rs11209032 genotype frequencies in AS group were 31.1% for GG, 50.9% for GA, and 17.9% for AA; while in control group, it was 34.1% for GG, 53.7% for GA, and 12.2% for AA. Distribution of rs1004819 genotype frequencies in AS group were 30.2% for CC, 52.8% for CT, and 17.0% for TT; while in control group, it was 42.7% for CC, 46.3% for CT, and 11.0% for TT. There was no significant difference between AS patients and controls in terms of genotype frequencies of IL-23R gene rs11209032 and rs1004819 polymorphisms.

Conclusion

No association was found between AS and IL23R rs11209032 and rs1004819 polymorphisms in this Turkish AS cohort.

Ankylosing Spondylitis: A rheumatology clinic experience

OBJECTIVE

To determine the frequency, demographics, laboratory and radiological features in patients with Ankylosing Spondylitis.

METHODS

This is a retrospective analysis of prospectively collected data of patients with a diagnosis of Ankylosing Spondylitis (AS), based on Modified New York criteria. The study was conducted at the Rheumatology Clinic of Jinnah Postgraduate Medical Centre (JPMC), from February 2004 to February 2014. Detailed history, examination and laboratory investigations were recorded in a pre-designed structured proforma. The frequency, demographic characteristics, extra-articular features and associated co-morbidities were studied.

RESULTS

A total of 603 patients were registered in our Rheumatology Clinic during this period, with a definitive diagnosis of inflammatory rheumatological disorders. Out of these, Ankylosing Spondylitis (AS) was diagnosed in 32 (5.3%) patients. 24 were male and 8 patients were female. The commonest affected age group was between 21-40 years. Majority of the patients belonged to Pathan ethnicity.

CONCLUSION

The demographic features of AS are same as reported in earlier studies from other parts of the world. The predominance of AS in specific ethnic groups is a fact that needs to be studied. Larger studies are required for clarifying the triggers of this disease. It often leads to severe disability, hence an early diagnosis and prompt treatment is required for better disease control and quality of life.

Prevalence of extra-articular manifestations in patients with ankylosing spondylitis: a systematic review and meta-analysis

OBJECTIVES

Uveitis, psoriasis and inflammatory bowel disease (IBD) are common extra-articular manifestations (EAM) in patients with ankylosing spondylitis (AS); however, summary data of reported prevalence are lacking. The aim of the present study was to summarise the prevalence of EAMs among patients with AS and to identify underlying factors to explain potential heterogeneity of prevalence.

METHODS

A systematic literature search was performed (Medline, Embase and Cochrane Library) to identify relevant articles. Risk of bias was assessed and data were extracted. Pooled prevalences were calculated. Potential sources of any observed clinical or methodological heterogeneity in the estimates were explored by subgroup and metaregression analysis.

RESULTS

In the 156 selected articles, 143 reported the prevalence of uveitis (44 372 patients), 56 of psoriasis (27 626 patients) and 69 of IBD (30 410 patients). Substantial heterogeneity was observed in prevalence estimates among all EAMs (I(2)=84-95%). The pooled prevalence of uveitis was 25.8% (95% CI 24.1% to 27.6%), and was positively associated in multivariable metaregression with disease duration (β 0.05, 95% CI 0.03 to 0.08) and random selection of patients (β -0.24, 95% CI -0.43 to -0.04). The pooled prevalence of psoriasis was 9.3% (95% CI 8.1% to 10.6%). The pooled prevalence of IBD was 6.8% (95% CI 6.1% to 7.7%) and was positively associated with the percentage of women in the studies (β 0.02, 95% CI 0.00 to 0.03). Geographical area was associated in multivariable metaregressions with prevalence of all EAMs.

CONCLUSIONS

EAMs are common in patients with AS. The large heterogeneity between studies can be partly explained by differences in clinical as well as methodological characteristics.

Association of IL-4 gene VNTR variant with deep venous thrombosis in Behçet's disease and its effect on ocular involvement

PURPOSE

Behçet's disease (BD) is a systemic vasculitis characterized by inflammatory lesions of the urogenital mucosa, eyes, skin, central nervous system, and joints. Vein thrombosis constitutes the most frequent vascular manifestation of the disease, and may cause such ocular vascular thrombotic events as central retinal vein and central retinal artery thrombosis. Thrombosis is a serious problem, and often leads to irreversible vision loss. Previous studies have shown that genetic factors predispose individuals to BD. Several cytokine genes might play crucial roles in host susceptibility to BD and to thrombophilia. Various polymorphic regions of the interleukin-4 (IL-4) gene (-1098G and 590T) are associated with BD in the Turkish population. This study was conducted in Turkish patients with BD to determine the frequency of the IL-4 gene 70 bp variable number of tandem repeats (VNTR) variant, and its association with clinical findings.

METHODS

Genomic DNA obtained from 488 individuals (238 patients with Behçet's disease and 250 healthy controls) was used in the study. Genomic DNA was isolated and genotyped using PCR assay for the IL-4 gene 70 bp VNTR polymorphism determined by using PCR with the specific primers.

RESULTS

There was statistical significance between the groups regarding IL-4 genotype distribution (p<0.001, odds ratio: 2.55 [1.629-4.052], 95% confidence interval) and allele frequencies (p<0.0012.381[1.586-3.617], 95% confidence interval). When we examined IL-4 genotype frequencies according to the clinical characteristics, we observed a statistically significant association between the P₂P₂ genotype and deep venous thrombosis (p=0.01). Deep venous thrombosis was also associated with ocular involvement in our study group (p=0.014).

CONCLUSIONS

Our findings suggest that the IL-4 gene 70 bp VNTR polymorphism is associated with susceptibility to development of BD. Deep venous thrombosis is also associated with ocular involvement in BD. The IL-4 gene could be a genetic biomarker in Behçet's disease in a Turkish study population.

Significant association between insertion/deletion polymorphism of the angiotensin-convertig enzyme gene and ankylosing spondylitis

PURPOSE

Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease that characteristically affects the sacroiliac joints and the spine. Also iritis and uveitis can be serious complications of AS that can damage the eye and impair vision. The exact pathogenesis of AS remains poorly understood but genetic factors play a key role in its development. Human leukocyte antigen B27 (HLA-B27) is the major genetic susceptibility marker in AS. To our knowledge, angiotensin converting enzyme (ACE) gene I/D polymorphisms have not yet been investigated in AS patients in Turkish population.This study was conducted in Turkish patients with AS to determine the frequency of I/D polymorphism genotypes of angiotensin converting enzyme gene.

METHODS

Genomic DNA obtained from 262 persons (122 patients with ankylosing spondylitis and 140 healthy controls) was used in the study. ACE I/D polymorphism genotypes were determined by using polymerase chain reaction with specific primers.

RESULTS

There was statistically significant difference between the groups with respect to genotype distribution (p<0.001). When we examine ACE genotype frequencies according to the clinical characteristics there was a statistically significant association between DD genotype and ocular involvement (p=0.04) also sacroiliac joint involvement (p=0.03).

CONCLUSIONS

As a result of our study, angiotensin converting enzyme gene I/D polymorphism DD genotype could be a genetic marker in ankylosing spondylitis in a Turkish study population.