Sponyloarthritis features forecasting the presence of HLA-B27 or sacroiliitis on magnetic resonance imaging in patients with suspected axial spondyloarthritis: results from a cross-sectional study in the ESPeranza Cohort

Quantification of Bone Marrow Edema by MRI of the Sacroiliac Joints in Patients Diagnosed with Axial Spondyloarthritis: Results from the ESPeranza Cohort

Objective: To evaluate whether the quantification of bone marrow edema (BMO) of the sacroiliac (SI) joints by magnetic resonance imaging (MRI) improves capacity for axial spondyloarthritis (axSpA) classification in comparison with the assessment of sacroiliitis by Assessment of SpondyloArthritis international Society (ASAS) classification criteria.Method: This prospective study from the ESPeranza cohort involved 66 subjects with an available MRI of the SI joints at baseline. This subgroup includes patients with axSpA (n = 28), peripheral spondyloarthritis (n = 10), and other diagnoses that were not spondyloarthritis (n = 28). Measures of diagnostic usefulness [area under the curve (AUC), sensitivity, specificity, Youden's J statistic, positive and negative likelihood ratios (LR+ and LR-)] were calculated for MRI of the SI joints according to ASAS criteria and for MRI quantified by means of SCAISS (Spanish tool for semi-automatic quantification of sacroiliac inflammation by MRI in spondyloarthritis). This analysis was stratified in patients who were human leucocyte antigen (HLA)-B27 positive and negative.Results: The AUC value with BMO quantification was 0.919 [95% confidence interval (CI) 0.799-1] for HLA-B27-positive patients and 0.884 (95% CI 0.764-1) for HLA-B27-negative patients. A SCAISS cut-off point of 80 units obtained a specificity of 94.4% and LR+ 7.5, while assessment by ASAS criteria showed a specificity value of 90% and LR+ 6.4.Conclusion: For patients with suspected axSpA, quantification of BMO improves the predictive capacity of MRI of the SI joints, for both HLA-B27-positive and HLA-B27-negative patients.Axial spondyloarthritis (axSpA) has a dramatic impact on physical function and quality of life (1). Despite its significant impact, patients with axSpA are normally diagnosed several years after presenting symptoms (2). In this respect, magnetic resonance imaging (MRI) of the sacroiliac (SI) joints has gained significance over the past decade, particularly in the early stages of the disease. Nowadays, imaging tests and human leucocyte antigen (HLA)-B27 testing are among the most important diagnostic procedures for patients with suspected axSpA.

Predictive values of inflammatory back pain, positive HLA B27 antigen and acute and chronic magnetic resonance changes in early diagnosis of Spondyloarthritis. A study of 133 patients

OBJECTIVES

To analyse the predictive values of inflammatory back pain (IBP), positive HLA B27 antigen, increased C-reactive protein (CRP), Spondyloarthritis (SpA) features, familial history (FH), magnetic resonance sacroiliac joints (MRI-SIJ) imaging and its weight in early SpA diagnosis.

METHODS

133 patients with back pain, aged <50, duration of the pain <2 years were included. Data such as IBP, HLA B27, increased CRP, SpA features, FH, SIJ´s radiography and MRI were collected for each patient. STIR sequences were classified as strongly positive bone morrow oedema (SPBME ≥2), clearly present and easily recognisable as positive according to the ASAS criterion, weakly positive (WPBME ≥2), suggestive, but not easily recognisable and, clearly negative none of those features. T1-weighted sequences were assessed as positive/negative for erosion, fat metaplasia, backfill and sclerosis, if ≥1, for each lesion was present. MRI images were read by three blinded readers.

RESULTS

The average age was 38.9 years. 47 (35.3%) patients received SpA diagnosis according to the clinical opinion. IBP was highly specific, 0.81 and sensitive, 0.83. HLA B27 was positive in a half of the SpA patients. SPBME ≥2 provided a great specificity, 0.94 and an acceptable sensitivity, 0.79. Erosion was significantly more frequent in SpA patients (72% vs 7%), specificity 0.93. The addition of erosion ≥1 to the WPBME ≥2 noticeably improved specificity, 0.98, although slightly decreased sensitivity, 0.64. Fat metaplasia and backfill were highly specific, but poorly sensitive. Factors forecasting positive diagnosis were IBP, followed by SpA features and increased CRP.

CONCLUSIONS

At the onset, IBP might be a good marker for selecting patients with suspicion of SpA. The addition of erosion to the ASAS criterion might be helpful for early diagnosis, especially in patients with doubtful STIR imaging where BME is present but it is hard to determinate whether the ASAS "highly suggestive" criterion is met.

Imaging Findings Suggestive of Axial Spondyloarthritis in Diffuse Idiopathic Skeletal Hyperostosis

OBJECTIVE

To describe the magnetic resonance imaging (MRI) findings in diffuse idiopathic skeletal hyperostosis (DISH) patients and to assess the proportion of DISH patients whose MRI findings would fulfill the Assessment of Spondyloarthritis International Society (ASAS) criteria for a positive MRI of axial spondyloarthritis (SpA).

METHODS

This study involved all DISH patients who had a spine or sacroiliac (SI) joint MRI performed between January 2009 and December 2014. Sociodemographic and clinical data were collected. Available radiographs and MRI were analyzed and blindly scored by an experienced reader, using the Spondyloarthritis Research Consortium of Canada (SPARCC) scores for both spine and SI joint MRI.

RESULTS

A total of 53 symptomatic DISH patients was included in the analysis. The mean ± SD SPARCC score of the spine was 18.3 ± 23.4. Thirty-five patients (67.3%) had at least 1 fatty corner. Thirty patients (57.7%) met the ASAS definition of a spine MRI suggestive of axial SpA, but only 6 patients (15.8%) with an available SI joint MRI had sacroiliitis according to ASAS criteria. Only 1 patient (3.3%) had ≥3 erosions on the SI joint.

CONCLUSION

Inflammatory lesions of the spine are common on the MRI of symptomatic DISH patients, and more than half fulfilled the ASAS criteria for a spine MRI suggestive of axial SpA. However, only a few patients met the ASAS definition of active sacroiliitis, suggesting that MRI of the SI joint but not of the spine might allow the differential diagnosis of DISH versus axial SpA in the elderly.

Frequency of sacroiliitis among patients with low back pain

Introduction

Sacroiliitis is one of the important symptoms in patients attending infectious diseases and rheumatology clinics. Some patients with sacroiliitis are asymptomatic, and some have unspecific symptoms. The aim of this study was to determine the frequency of sacroiliitis causes among patients attending Shahid Sadoughi’s infectious disease and rheumatology clinics.

Methods

In this study, we evaluated patients attending Shahid Sadoughi rheumatology and infectious diseases clinic in 2014. Patients who had positive findings in favor of sacroiliitis were evaluated by history, physical exam, laboratory tests, and imaging. The patients were divided into infectious, inflammatory non-infectious, and degenerative causes. The data were analyzed by IBM SPSS version 20 using the independent samples t-test, ANOVA, the chi-squared test, and the Fisher’s exact test.

Results

We studied 136 patients. Among them 64 (47.1%) were male, and 72 (52.9%) were female. The mean age of the participants was 34.28 ± 10.36 years. Among the patients, 12 (8.8%) had infectious causes, 120 (88.2%) had inflammatory non-infectious causes, and four (2.9%) had degenerative causes.

Conclusion

Based on our results, inflammatory non-infectious causes are at the top of the list of sacroiliitis causes, but we should always consider infectious causes, including brucellosis.