Clinical remission and subsequent relapse in patients with juvenile idiopathic arthritis: predictive factors according to therapeutic approach.

BACKGROUND: Juvenile idiopathic arthritis constitutes a significant cause of disability and quality of life impairment in pediatric and adult patients. The aim of this study was to ascertain clinical remission (CR) and subsequent relapse in juvenile idiopathic arthritis (JIA) patients, according to therapeutic approach and JIA subtype. Evidence in literature regarding its predictors is scarce. METHODS: We conducted an observational, ambispective study. Patients diagnosed of JIA, treated with synthetic and/or biologic disease modifying antirheumatic drugs (DMARD) were included and followed-up to December 31st, 2015. Primary outcome was clinical remission defined by Wallace criteria, both on and off medication. In order to ascertain CR according to therapeutic approach, DMARD treatments were divided in four groups: 1) synthetic DMARD (sDMARD) alone, 2) sDMARD combined with another sDMARD, 3) sDMARD combined with biologic DMARD (bDMARD), and 4) bDMARD alone. RESULTS: A total of 206 patients who received DMARD treatment were included. At the time the follow-up was completed, 70% of the patients in the cohort had attained CR at least once (144 out of 206), and 29% were in clinical remission off medication (59 out of 206). According to treatment group, CR was more frequently observed in patients treated with synthetic DMARD alone (53%). Within this group, CR was associated with female sex, oligoarticular persistent subtypes, ANA positivity, Methotrexate treatment and absence of HLA B27, comorbidities and DMARD toxicity. 124 DMARD treatments (62%) were withdrawn, 64% of which relapsed. Lower relapse rates were observed in those patients with persistent oligoarticular JIA (93%) when DMARD dose was tapered before withdrawal (77%). CONCLUSIONS: More than two thirds of JIA patients attained CR along the 9 years of follow-up, and nearly one third achieved CR off medication. Females with early JIA onset, lower active joint count and ANA positivity were the ones achieving and sustaining remission more frequently, especially when receiving synthetic DMARD alone and in the absence of HLA B27, comorbidities or previous DMARD toxicity.

Atlas of axial spondyloarthritis in Spain 2017: Study design and population.

OBJECTIVE: Atlas of Axial Spondyloarthritis in Spain 2017 aims to better understand the reality of the patients suffering from this disease from an integrated approach. METHODS: The Atlas 2017 based its results on an extensive cross-sectional patient survey conducted in Spain (2016), validated by a multidisciplinary group of experts on spondyloarthritis. RESULTS: Data from 680 patients with axSpA were obtained, most of them suffered from AS, were HLA-B27 positive, older than 45 years, and live as part of a couple. A large percentage had university studies, were disabled and members of a patient association. Patients reported a diagnostic delay of 8.5 years, high disease activity (BASDAI 5.5±2.2), moderate-important stiffness (61.0%), medium-high functional limitation (74.9%), and psychological distress (GHQ 5.7±4.5). A total of 54.7% reported taking NSAIDs, 28.4% DMARDs, 36.3% biological therapy and 32.2% were not receiving pharmacological treatment. CONCLUSIONS: The Atlas survey data reveals still a long diagnostic delay, high disease activity, psychological distress, while an important proportion could be undertreated.

Assessment of preclinical atherosclerosis in patients with ankylosing spondylitis.

OBJECTIVE: Epidemiological studies recently confirmed the increased risk of vascular morbidity and mortality during ankylosing spondylitis (AS). Increase of intima-media thickness (IMT) of the common carotid artery is a useful and noninvasive marker of preclinical atherosclerosis. The aim of our study was to compare IMT in patients with AS with matched controls and to determine risk factors of atherosclerosis related to AS. METHODS: We performed a prospective study of 60 consecutive patients meeting modified New York criteria for AS, compared to 60 controls matched for age and sex. Disease-specific measures were determined. Measurement of IMT was performed by the same radiologist using the same machine and probe in right and left common carotid arteries, and the average of the 2 measurements was considered. RESULTS: In total 48 male and 12 female patients were recruited, and 60 corresponding controls; mean age was 36 ± 11 years. We found significantly increased IMT in the AS group (0.51 ± 0.12 mm) compared with controls (0.39 ± 0.09 mm; p = 0.001). After adjustment for confounding factors, increased IMT was still present (p = 0.003). Age at onset of AS (p = 0.001), Bath AS Disease Activity Index (p = 0.002), AS Disease Activity Score (ASDAS) erythrocyte sedimentation rate (ESR; p = 0.047), ASDAS C-reactive protein (CRP; p = 0.012), Bath AS Functional Index (p = 0.008), global spine visual analog scale for pain (p = 0.000), Schober index (p = 0.039), Bath AS Metrology Index (p = 0.028), modified Stoke Ankylosing Spondylitis Spine Score (p = 0.035), and high ESR (p = 0.001) and CRP (p = 0.000) were correlated with high IMT in patients with AS. Otherwise, status of arthritis (p = 0.442), enthesitis (p = 0.482), and HLA-B27 (p = 0.528) seemed to have no effect on IMT. CONCLUSION: AS is associated with an increased risk of atherosclerosis independent of traditional risk factors. Disease activity, functional and mobility limitations, structural damage, and inflammation are the most incriminated risk factors.

HLA-B27 testing in Thai patients using the PCR-SSP technique.

We develop the HLA-B27 test kit using the PCR-SSP technique. Five hundred forty blood samples were tested for HLA-B27 by microlymphocytotoxicity test (LCT) and PCR-SSP. It was found that 127 (23.5%) and 134 (24.8%) of these samples were positive for HLA-B27 by LCT and PCR-SSP, respectively. The sensitivity and specificity of the PCR-SSP were 94.8 and 100%, respectively, when using LCT as the standard method. The PCR-SSP positive predictive value was 100%, negative predictive value was 98.3%, and a concordance rate of 98.7%. This study shows that the PCR-SSP is simple, convenient, and a more cost-effective in-house test kit.

Clinical assessment of sacroiliitis and HLA-B27 are poor predictors of sacroiliitis diagnosed by magnetic resonance imaging in psoriatic arthritis.

OBJECTIVE: To determine the frequency and clinical predictors of sacroiliitis diagnosed by magnetic resonance imaging (MRI) in a psoriatic arthritis (PsA) population. METHODS: The studied comprised 103 patients with PsA. A careful clinical assessment for sacroiliitis was made from history and examination, and HLA-B27 testing was performed. Sixty-eight patients underwent tilted coronal fat-saturated T1-weighted and STIR MRI of the sacroiliac joints. RESULTS: Clinical features of moderate or severe sacroiliitis were found in 24/68 (35%) patients. MRI features of sacroiliitis were found in 26/68 (38%) patients. Clinical features of sacroiliitis were present in 14/42 (33%) with normal MRI scans and 10/26 (38%) with abnormal scans (normal vs abnormal scans, P = 0.7). The presence of sacroiliitis on MRI was associated with restricted spinal movements (P = 0.004) and the duration of PsA (P = 0.04). There was no correlation between HLA-B27 and sacroiliitis diagnosed by MRI. CONCLUSION: Sacroiliitis diagnosed by MRI occurs commonly in PsA but is difficult to detect clinically.

HLA-B27 allele diversity in Indians: impact of ethnic origin and the caste system.

HLA-B27 is a serological specificity which encompasses an increasing number of subtypes that show varied racial/ethnic prevalence in the world. Here, data from 5129 Indians (4500 population and caste; 629 tribal) is compiled from the literature. In addition, HLA-B27 subtyping of 58 positive individuals from Maharastra is presented. Analysis revealed an increased B27 antigen frequency among the north Indian groups (>5%) compared to the south Indian groups (<5%). HLA-B27 subtyping identified B*2704 (34.48%), B*2705 (36.2%), B*2707 (15.51%), B*2708 (10.34%) and B*2714 (3.44%) alleles in the population groups from Maharastra, but these differed in their distribution among the caste and tribal groups studied. The study showed that more extensive subtyping in other Indian caste groups will be necessary to resolve the evolutionary implications of HLA-B27 subtypes and their relationship to disease association in the Indian context.

The detection of the HLA-B27 antigen by immunomagnetic separation and enzyme-linked immunosorbent assay-comparison with a flow cytometric procedure.

The HLA-B27 antigen is an important genetic marker in ankylosing spondylitis (AS). Methods for the detection of B27 include the microlymphocytotoxicity test and, more recently, flowcytometry (FC). Here, we describe a new method, IMS-ELISA, for measuring the B27-antigen. It combines immunomagnetic separation (IMS), to obtain B27-positive cells from whole blood samples, with an enzyme-linked immunosorbent assay (ELISA) as a read-out. IMS-ELISA was tested on 367 samples obtained from five different hospitals in Taiwan. The sensitivity, specificity and accuracy of the method were compared with FC. Any conflicting data between IMS-ELISA and FC was confirmed by HLA-DNA typing via PCR-SSP (polymerase chain reaction-sequence specific primers). Overall, the results for sensitivity, specificity and accuracy obtained by IMS-ELISA and FC did not show any significant difference (p>0.05). However, when considering laboratory time, cost, ease of operation and the screening of large samples for HLA-B27, the IMS-ELISA was superior to the FC method. We conclude that IMS-ELISA may be used as a fast screening method for HLA B27 detection.

External quality assessment of flow cytometric HLA-B27 typing.

A biannual external quality assurance (EQA) scheme for flow cytometric typing of the HLA-B27 antigen is operational in The Netherlands and Belgium since 1995. We report here on the results of the first seven send-outs to which 36 to 47 laboratories participated. With the send-out, four specimens from blood bank donors, who had been typed for HLA Class I antigens by complement-dependent cytotoxicity, were distributed. Subtyping of the HLA-B27 allele was performed by PCR-SSP. Ten samples were HLA-B27(pos) (all HLA-B*2705) and 18 were HLA-B27(neg). For flow cytometry, the most widely monoclonal antibody (MoAb) used was FD705, followed by GS145.2 and ABC-m3. The majority of laboratories used more than 1 anti-HLA-B27 MoAb for typing. The HLA-B27(pos) samples were correctly classified as positive by the large majority of participants (median 95%; range 85% to 100% per send out); some participants considered further typing necessary and misclassification as negative was only sporadically seen. The classification of HLA-B27(neg) samples as negative was less straightforward. Ten samples were correctly classified as such by 97% (82% to 100%) of the participants, whereas 64% (range 53% to 70%) of the participants classified the remaining eight samples as HLA-B27(neg). There was no significant prevalence of a particular HLA-B allele among these eight "poor concordancy" samples as compared to the ten "good concordancy" samples. Inspection of the reactivity patterns of the individual MoAb with HLA-B27(neg) samples revealed that ABC-m3 showed very little cross-reactivity apart from its well-known cross-reactivity with HLA-B7, whereas the cross-reactivity patterns of GS145.2 and FD705 were more extensive. The small sample size (n = 18) and the distribution of HLA-B alleles other than HLA-B27 did not allow assignment of specificities to these cross-reactions. Finally, we showed that standardized interpretation of the combined results of two anti-HLA-B27 MoAb reduced the frequency of false-positive conclusions on HLA-B27(neg) samples. In this series, the lowest frequency of false-positive assignments was observed with the combination of the FD705 and ABC-m3 MoAb.

Assessment of 2 systems of spondyloarthropathy diagnostic and classification criteria (Amor and ESSG) by a Spanish multicenter study. European Spondyloarthropathy Study Group.

OBJECTIVE: To assess the 2 most recently developed sets of spondylarthropathy (SpA) diagnostic and classification criteria [Amor and the European Spondyloarthropathy Study Group (ESSG)] in a survey involving a Spanish population with rheumatic disease. METHODS: The survey involved a cross sectional study of 1549 patients with rheumatic disease, who were examined over a week by 36 expert rheumatologists at 28 Spanish rheumatological centers. The head researcher at each participating center was to diagnose patients as having definite SpA, possible SpA, or as having other rheumatic diseases (definite controls) based on the physician's experience and assessment with no reference to the criteria under study. RESULTS: Overall a total of 218 patients were classified as having definite SpA, 1242 as definite controls and 89 as having possible SpA. An analysis of the patients diagnosed as definite showed 90.8 and 83.5% sensitivity, 96.2 and 95.2% specificity, 80.8 and 75.5% positive predictive value, and 98.4 and 97.0% negative predictive value for the Amor and ESSG criteria sets, respectively. CONCLUSIONS: Both the Amor and ESSG criteria had excellent intrinsic (sensitivity and specificity) and extrinsic (positive and negative predictive value) performance, with no substantial differences between the 2. The results support use of the criteria for classifying SpA in daily rheumatological practice. Although not intended as diagnostic criteria, they make useful tools for the early identification of initial, atypical, or undifferentiated forms, which fail to strictly meet the diagnostic criteria of the entities that make up the SpA group.