Radiomic Quantification for MRI Assessment of Sacroiliac Joints of Patients with Spondyloarthritis

Spondyloarthritis (SpA) is a group of diseases primarily involving chronic inflammation of the spine and peripheral joints, as evaluated by magnetic resonance imaging (MRI). Considering the complexity of SpA, we performed a retrospective study to discover quantitative/radiomic MRI-based features correlated with SpA. We also investigated different fat-suppression MRI techniques to develop detection models for inflammatory sacroiliitis. Finally, these model results were compared with those of experienced musculoskeletal radiologists, and the concordance level was evaluated. Examinations of 46 consecutive patients were obtained using SPAIR (spectral attenuated inversion recovery) and STIR (short tau inversion recovery) MRI sequences. Musculoskeletal radiologists manually segmented the sacroiliac joints for further extraction of 230 MRI features from gray-level histogram/matrices and wavelet filters. These features were associated with sacroiliitis, SpA, and the current biomarkers of ESR (erythrocyte sedimentation rate), CRP (C-reactive protein), BASDAI (Bath Ankylosing Spondylitis Activity Index), BASFI (Bath Ankylosing Spondylitis Functional Index), and MASES (Maastricht Ankylosing Spondylitis Enthesis Score). The Mann-Whitney U test showed that the radiomic markers from both MRI sequences were associated with active sacroiliitis and with SpA and its axial and peripheral subtypes (p < 0.05). Spearman's coefficient also identified a correlation between MRI markers and data from clinical practice (p < 0.05). Fat-suppression MRI models yielded performances that were statistically equivalent to those of specialists and presented strong concordance in identifying inflammatory sacroiliitis. SPAIR and STIR acquisition protocols showed potential for the evaluation of sacroiliac joints and the composition of a radiomic model to support the clinical assessment of SpA.

Clinical application of mesenchymal stem cells in rheumatic diseases

Mesenchymal stem cells (MSCs) are pluripotent stem cells derived from mesoderm during early development that are characterized by high self-renewal ability and multidirectional differentiation potential. These cells are present various tissues in the human body and can be cultured in vitro. Under specific conditions, MSCs can differentiate into osteoblasts, neuron-like cells, adipocytes and muscle cells and so on, therefore, have a great application value in cell replacement therapy and tissue repair. In recent years, the application of MSCs in rheumatic diseases has received increasing attention. On the one hand, MSCs have the ability to differentiate into bone and cartilage cells; on the other hand, these stem cells are also involved in immune regulation, resulting in the alleviation of inflammation and anti-fibrotic properties and the promotion of vascular repair, thus bringing new hope for the treatment of rheumatic diseases. This article reviews the clinical progress in MSC application for the treatment of rheumatic diseases.

GM-CSF Expression and Macrophage Polarization in Joints of Undifferentiated Arthritis Patients Evolving to Rheumatoid Arthritis or Psoriatic Arthritis

Background and Aims

GM-CSF-dependent macrophage polarization has been demonstrated in rheumatoid arthritis (RA). Our aim was to seek diagnostic/prognostic biomarkers for undifferentiated arthritis (UA) by analyzing GM-CSF expression and source, macrophage polarization and density in joints of patients with UA evolving to RA or PsA compared with established RA or PsA, respectively.

Methods

Synovial tissue (ST) from patients with UA evolving to RA (UA>RA, n=8), PsA (UA>PsA, n=9), persistent UA (UA, n=16), established RA (n=12) and PsA (n=10), and healthy controls (n=6), were analyzed. Cell source and quantitative expression of GM-CSF and proteins associated with pro-inflammatory (GM-CSF-driven) and anti-inflammatory (M-CSF-driven) macrophage polarization (activin A, TNFα, MMP12, and CD209, respectively) were assessed in ST CD163⁺ macrophages by multicolor immunofluorescence. GM-CSF and activin A levels were also quantified in paired synovial fluid samples. CD163⁺ macrophage density was determined in all groups by immunofluorescence.

Results

Synovial stromal cells (FAP⁺ CD90⁺ fibroblast, CD90⁺ endothelial cells) and CD163⁺ sublining macrophages were the sources of GM-CSF. ST CD163⁺ macrophages from all groups expressed pro-inflammatory polarization markers (activin A, TNFα, and MMP12). Expression of the M-CSF-dependent anti-inflammatory marker CD209 identified two macrophage subsets (CD163⁺ CD209^high and CD163⁺ CD209^low/-). CD209⁺ macrophages were more abundant in ST from healthy controls and PsA patients, although both macrophage subtypes showed similar levels of pro-inflammatory markers in all groups. In paired synovial fluid samples, activin A was detected in all patients, with higher levels in UA>RA and RA, while GM-CSF was infrequently detected. ST CD163⁺ macrophage density was comparable between UA>RA and UA>PsA patients, but significantly higher than in persistent UA.

Conclusions

GM-CSF is highly expressed by sublining CD90⁺ FAP⁺ synovial fibroblasts, CD90⁺ activated endothelium and CD163⁺ macrophages in different types of arthritis. The polarization state of ST macrophages was similar in all UA and established arthritis groups, with a predominance of pro-inflammatory GM-CSF-associated markers. CD163⁺ macrophage density was significantly higher in the UA phases of RA and PsA compared with persistent UA. Taken together, our findings support the idea that GM-CSF is a strong driver of macrophage polarization and a potential therapeutic target not only in RA but also in PsA and all types of UA.

Ectopic bone formation and systemic bone loss in a transmembrane TNF-driven model of human spondyloarthritis

BACKGROUND

The transmembrane-TNF transgenic mouse, TgA86, has been shown to develop spontaneously peripheral arthritis with signs of axial involvement. To assess similarity to human spondyloarthritis, we performed detailed characterization of the axial, peripheral, and comorbid pathologies of this model.

METHODS

TgA86 bone pathologies were assessed at different ages using CT imaging of the spine, tail vertebrae, and hind limbs and characterized in detail by histopathological and immunohistochemical analysis. Cardiac function was examined by echocardiography and electrocardiography and bone structural parameters by μCT analysis. The response of TgA86 mice to either early or late anti-TNF treatment was evaluated clinically, histopathologically, and by μCT analysis.

RESULTS

TgA86 mice developed with 100% penetrance spontaneous axial and peripheral pathology which progressed with time and manifested as reduced body weight and body length, kyphosis, tail bendings, as well as swollen and distorted hind joints. Whole-body CT analysis at advanced ages revealed bone erosions of sacral and caudal vertebrae as well as of sacroiliac joints and hind limbs and, also, new ectopic bone formation and eventually vertebral fusion. The pathology of these mice highly resembled that of SpA patients, as it evolved through an early inflammatory phase, evident as enthesitis and synovitis in the affected joints, characterized by mesenchymal cell accumulation, and neutrophilic infiltration. Subsequently, regression of inflammation was accompanied by ectopic bone formation, leading to ankylosis. In addition, both systemic bone loss and comorbid heart valve pathology were evident. Importantly, early anti-TNF treatment, similar to clinical treatment protocols, significantly reduced the inflammatory phase of both the axial and peripheral pathology of TgA86 mice.

CONCLUSIONS

The TgA86 mice develop a spontaneous peripheral and axial biphasic pathology accompanied by comorbid heart valvular dysfunction and osteoporosis, overall reproducing the progression of pathognomonic features of human spondyloarthritis. Therefore, the TgA86 mouse represents a valuable model for deciphering the role of transmembrane TNF in the pathogenic mechanisms of spondyloarthritis and for assessing the efficacy of human therapeutics targeting different phases of the disease.

Recommendation for the Management of Spondyloarthritis Patients in Kuwait

OBJECTIVE

In 2016, ASAS and EULAR made joint recommendations for the management of patients with spondyloarthritis. Although Global and European perspectives are important, they cannot accurately reflect the situation for all patients in all countries and regions. As such, the group worked to tailor the existing international recommendations to suit the specific demographic needs of local populations in the Gulf region, with a specific focus on Kuwait.

METHODS

Recommendations drafted following a PubMed search for relevant literature were reviewed and then underwent Delphi vote to reach consensus on those to be included. Advice for newly approved agents, including targeted synthetic disease-modifying anti-rheumatic drugs, was included based on the group's clinical experience.

RESULTS

The resulting 41 recommendations are grouped into five categories covering key definitions and principles for the management and treatment of both axial and peripheral forms of spondyloarthritis.

CONCLUSION

Through adaptation of existing guidelines and incorporating the current evidence and clinical experience of the members of the group, these recommendations have been developed to reflect the unique situation in Kuwait with regard to differing patient profiles, local culture and approved therapeutic approaches, and are designed to aid in clinical decision-making.

A study of MRI-based radiomics biomarkers for sacroiliitis and spondyloarthritis

PURPOSE

To evaluate the performance of texture-based biomarkers by radiomic analysis using magnetic resonance imaging (MRI) of patients with sacroiliitis secondary to spondyloarthritis (SpA).

RELEVANCE

The determination of sacroiliac joints inflammatory activity supports the drug management in these diseases.

METHODS

Sacroiliac joints (SIJ) MRI examinations of 47 patients were evaluated. Thirty-seven patients had SpA diagnoses (27 axial SpA and ten peripheral SpA) which was established previously after clinical and laboratory follow-up. To perform the analysis, the SIJ MRI was first segmented and warped. Second, radiomics biomarkers were extracted from the warped MRI images for associative analysis with sacroiliitis and the SpA subtypes. Finally, statistical and machine learning methods were applied to assess the associations of the radiomics texture-based biomarkers with clinical outcomes.

RESULTS

All diagnostic performances obtained with individual or combined biomarkers reached areas under the receiver operating characteristic curves ≥ 0.80 regarding SpA related sacroiliitis and and SpA subtypes classification. Radiomics texture-based analysis showed significant differences between the positive and negative SpA groups and differentiated the axial and peripheral subtypes (P < 0.001). In addition, the radiomics analysis was also able to correctly identify the disease even in the absence of active inflammation.

CONCLUSION

We concluded that the application of the radiomic approach constitutes a potential noninvasive tool to aid the diagnosis of sacroiliitis and for SpA subclassifications based on MRI of sacroiliac joints.

Psoriatic spondylitis or ankylosing spondylitis with psoriasis: same or different?

PURPOSE OF REVIEW

Of the four musculoskeletal domains of psoriatic arthritis (PsA), the axial domain is the least studied. With the advent of targeted therapy that is efficacious in some but not all manifestations of spondyloarthritis (SpA), there is interest in understanding the similarities and differences between axial PsA (axPsA) and ankylosing spondylitis. Moreover, there is also interest in evaluating the axial domain in PsA clinical trials, domain that has traditionally been ignored in such studies. This review aims to summarize the current understanding of the differences between ankylosing spondylitis and axPsA.

RECENT FINDINGS

Recent observational studies have shown that axPsA forms part of the SpA spectrum, flanked by peripheral PsA on one side and ankylosing spondylitis on the other. Thus, axial disease is more severe in ankylosing spondylitis, whereas peripheral disease is more severe in axPsA. However, the overall disease burden and impact is similar. The expression of axPsA is influenced by age, disease duration, sex and HLA-B27 status.

SUMMARY

axPsA has not been properly defined hampering research into pathogenesis, disease impact and treatment. Research to define prevalence, clinical features, impact, similarities and differences with other axial SpA, and treatment is an unmet need.

Patients with enthesitis related arthritis show similar monocyte function pattern as seen in adult axial spondyloarthropathy

BACKGROUND

Axial SpA and Enthesitis related arthritis (ERA) patients show strong HLA-B27 association, gut dysbiosis, high toll like receptor (TLR)2 and 4 expression on monocytes, pro-inflammatory cytokine production and elevated levels of TLR4 endogenous ligands [tenascin-c (TNC) and myeloid related protein (MRP)8/14] in serum. Hence, we aimed to understand if these diseases have similar or different monocyte response.

METHODS

Fifty adult axial SpA, 52 ERA patients and 25 healthy controls (HC) were enrolled. Cytokine-producing monocyte frequency before and after stimulation with lipopolysaccharide (LPS), peptidoglycan (PG), TNC or MRP8 were measured in whole blood (WB) and synovial fluid mononuclear cells (SFMC) by flow cytometry. Also, IL-6, TNF, MMP3, TNC and MRP8/14 levels were measured in unstimulated and TLR ligand stimulated WB cultures supernatant by ELISA. Finally, the mRNA expression levels of TNF and IL-6 were measured post stimulation with LPS, TNC and MRP8.

RESULTS

At baseline, ERA and axial SpA patients showed similar TNF-α producing monocyte frequency which was higher than HC. MRP8 simulation led to increased TNF-α producing monocyte frequency in ERA than axial SpA. TNC and MRP8 stimulation led to similar IL-6 producing monocyte frequency in axial SpA and ERA patients. Baseline TNF and IL-6 producing monocyte frequency also modestly correlated with disease activity scores. TNF and IL-6 producing monocyte frequency increased in response to TLR stimulation in SFMC from both patients. In culture supernatants, axial SpA and ERA patients showed similar TNF production at baseline. MRP8 and TNC stimulation led to higher TNF production from ERA. Baseline IL-6 and MMP3 production was higher in ERA while TLR stimulation led to similar IL-6 and MMP3 production from axial SpA and ERA. TNC stimulation led to higher MMP3 production in ERA. mRNA expression in response to TLR stimulation was observed to be similar in axial SpA and ERA. TNC production was higher in ERA at baseline, while MRP8/14 production was higher in axial SpA than ERA post stimulation.

CONCLUSION

ERA patients have similar monocyte response to exogenous and endogenous TLR ligands as patients with axial SpA. This suggests that differences between pediatric and adult-onset SpA are minimal and they may have a common pathogenesis.

Psoriatic arthritis: From pathogenesis to pharmacologic management

The pathogenesis of psoriatic arthritis (PSA) is still a matter of debate. A favourable genetic background is interwoven with environmental triggering factors in a complex network. Shared antigens and the recirculation of immune cells may account for the clinical manifestations, involving both cutaneous and articular sites. A favourable genetic background has been demonstrated in many genomic and proteomic studies, being associated to polymorphic variants of the genes coding for Major Histocompatibility Complex I and cytokine pathways. In genetic-predisposed individuals, triggering factors, like infections, dysbiosis or mechanic stress may promote the development of the disease. The subsequent activation of the innate and adaptive immune system, following the stimulation of Toll-like Receptors, culminates in the expansion of dendritic cells, macrophages, CD4+ and CD8+ T cells, neutrophils, monocytes, Natural Killer lymphocytes and other cells with the final inflammation and damage of skin, joint and enthesis. Particularly, the activation of CD4+ T helper 17 lymphocytes represents a crucial point in the pathogenesis of the disease. The participation of the visceral adipose tissue may amplify the inflammatory process by means of the synthesis of pro-inflammatory adipokines. Current therapeutic algorithms address the variety of clinical manifestations with a tailored strategy aiming to achieve the best control of the symptoms with minimal side effects. Conventional immunosuppressive drugs, biologic agents and synthetic small molecules offer different attack routes and may be chosen individually or in combination according to the phenotype of the disease.

Cross-sectional study of patients with axial spondyloarthritis fulfilling imaging arm of ASAS classification criteria: baseline clinical characteristics and subset differences in a single-centre cohort

OBJECTIVE

This study compared demographic, clinical and laboratory characteristics between patients with radiographic and non-radiographic axial spondyloarthritis (axSpA).

METHODS

In this single-centre cross-sectional study, a total of 246 patients with axSpA fulfilling the imaging arm of Assessment of SpondyloArthritis International Society classification criteria were recruited. A total of 140 patients were diagnosed as non-radiographic axial spondyloarthritis (nr-axSpA), and 106 patients had ankylosing spondylitis (AS). Sociodemographic characteristics, disease manifestations, clinical and laboratory disease activity and their differences between subsets were analysed. P values below 0.05 with CI 95% were considered statistically significant.

RESULTS

More nr-axSpA patients were women (61.4%) compared with 24.7% of AS patients. First symptoms developed earlier in AS patients compared with nr-axSpA (23.0 (IQR 17.5-30.0) vs 27.8 (IQR 21.0-33.7) years, p=0.001). Disease manifestations did not differ, but patients with nr-axSpA experienced peripheral arthritis more frequently (35.7% vs 17.0%, p=0.001) with less hip involvement (8.6% vs 18.9%, p=0.022) compared with patients with AS. Patients with AS exhibited worse spinal mobility and physical function compared with nr-axSpA. AS Disease Activity Scores and CRP levels were significantly higher in patients with AS compared with nr-axSpA (2.4 (IQR 1.7-2.8) vs 2.0 (IQR 1.1-2.3), p=0.022 and 7.1 (IQR 2.6-14.9) vs 2.5 (IQR 0.8-8.2) mg/L, p<0.001, respectively).

CONCLUSIONS

Our data demonstrated some known and also novel differences between the two imaging arm fulfilling axSpA subgroups. Non-radiographic patients were mostly women who had experienced shorter disease duration, milder disease activity and better functional status with less hip involvement but more peripheral arthritis compared with patients with AS.

The need for comparative data in spondyloarthritis

Spondyloarthritis comprises a group of inflammatory diseases, characterised by inflammation within axial joints and/or peripheral arthritis, enthesitis and dactylitis. An increasing number of biologic treatments, including biosimilars, are available for the treatment of spondyloarthritis. Although there are a growing number of randomised controlled trials assessing treatments in spondyloarthritis, there is a paucity of data from head-to-head studies. Comparative data are required so that clinicians and payers have the level of evidence required to inform clinical decision-making and health economic assessments. In the absence of head-to-head studies, statistical methods such as network meta-analyses and matching-adjusted indirect comparisons (MAICs) are used for assessing comparative effectiveness.

Network meta-analysis can be used to compare treatments for trials using a common comparator (e.g. placebo); however, for those without a common comparator or where considerable heterogeneity exists between the study populations, a MAIC that controls for differences in study design and baseline patient characteristics may be used. MAICs, unlike network meta-analyses, are of value for longer-term comparisons beyond the placebo-controlled phase of clinical trials, which is important for chronic diseases requiring long-term treatment, like spondyloarthritis. At present, there are a number of limitations that restrict the effectiveness of MAIC, such as the poor availability of individual patient-level data from trials, which results in patient-level data from one trial being compared with published whole-population data from another. Despite these limitations, drug reimbursement agencies are increasingly accepting MAIC as a means of comparative effectiveness and greater methodological guidance is needed.

This report highlights a number of challenges that are specific to conducting comparative studies like MAIC in spondyloarthritis, including disease heterogeneity, the paucity of biomarkers and the duration of studies required for radiographic endpoints in this slow-progressing disease.

Spondyloarthritis patients with and without intestinal symptoms - searching for discriminating biomarkers

Spondyloarthritis (SpA) is often complicated with subclinical gut inflammation. This study was aimed at searching for biomarkers discriminating SpA patients with and without intestinal symptoms. A group of 29 SpA patients and 33 healthy volunteers (control) were included in the study. Based on clinical evaluation, the patient cohort was subdivided into two groups: 1) SpA accompanied by various intestinal symptoms suggesting gut inflammation (group 2, n = 14) and 2) without such complications (group 1, n = 15). Serum concentrations of interleukins (IL) (IL-10, IL-17A/F, IL-22, IL-23), tumour necrosis factor (TNF), bone-homeostasis-related factors (osteoprotegerin – OPG and Dickkopf-1 – DKK-1), and the concentrations of selected gut inflammation-associated factors (intestinal fatty acid binding protein – iFABP, claudin 3 – CLDN3 and calprotectin) in samples of sera and/or urine or stool, respectively, were measured by specific ELISA. Serum concentrations of tested factors were similar in SpA patients and control. Faecal calprotectin level was higher in patients but did not discriminate between group 1 and 2. Compared to group 1, group 2 was characterized by elevated erythrocyte sedimentation rate (ESR), higher serum CLDN3 and DKK-1 levels. In SpA patients, serum DKK-1 concentrations correlated with systemic inflammation markers (R = 0.6, p < 0.01), while serum CLDN3 was found to be an independent risk factor (OR = 4.5, p = 0.021) for the occurrence of intestinal symptoms. We conclude that in SpA patients, up-regulated circulating levels of CLDN3 seem to be related to intestinal complication, while the quantity of circulating DKK-1 reflects the intensity of systemic inflammation.

Ankylosing spondylitis and mesenchymal stromal/stem cell therapy: a new therapeutic approach

Ankylosing spondylitis (AS) is an inflammatory rheumatoid disease categorized within spondyloarthropathies (SpA) and manifested by chronic spinal arthritis. Several innate and adaptive immune cells and secreted-mediators have been indicated to play a role in AS pathogenesis. Considering the limitations of current therapeutic approaches (NSAIDs, glucocorticoids, DMARDs and biologic drugs), finding new treatments with fewer side effects and high therapeutic potentials are required in AS. Mesenchymal stem cells (MSCs) with considerable immunomodulatory and regenerative properties could be able to attenuate the inflammatory responses and help tissue repair by cell-to-cell contact and secretion of soluble factors. Moreover, MSCs do not express HLA-DR, which renders them a favorable therapeutic choice for transplantation in immune-mediated disorders. In the present review, we describe immunopathogenesis and current treatments restrictions of AS. Afterwards, immunomodulatory properties and applications of MSCs in immune-mediated disorders, as well as recent findings of clinical trials involving mesenchymal stem cell therapy (MSCT) in ankylosing spondylitis, will be discussed in detail. Additional studies are required to investigate several features of MSCT such as cell origin, dosage, administration route and, specifically, the most suitable stage of disease for ideal intervention.

Genotypes, phenotypes and treatment with immunomodulators in the rheumatic diseases

The autoimmune rheumatological diseases rheumatoid arthritis (RA), spondyloarthritis (SpA) and systemic lupus erythematosus (SLE) are treated with conventional immunosuppressive agents and with modern biological immunomodulators. The latter group of medications have brought about a major change in our ability to control RA and SpA, with more modest results for SLE. The biologicals are very specific in their mechanisms of action, targeting one specific cytokine or one particular cellular marker. Because of this, their efficacy can readily be linked to a single immunomodulatory mechanism. This observation has fuelled hopes that the efficacy of these agents can be predicted at the individual level based on the patient's genetic predisposition, immunological profile or disease phenotype. Whilst the biologic therapies have improved the prospects for patients with these diseases very significantly, the hope that they could be targeted to the patient in an individualized manner has not completely born fruit. In this review, I will argue that we are witnessing important progress in this field, and that justified hope exists for true advances in precision medicine in the autoimmune diseases in the coming years.

Patient Burden of Axial Spondyloarthritis

Axial spondyloarthritis (AxSpA) is an inflammatory spondyloarthritis (SpA) that has significant impact on a patient's life. Symptoms, including fatigue, sleep problems, depression, and sexual dysfunction, can profoundly impact health-related quality of life (HRQoL) and limit work, leisure, and daily activities. Available therapies effectively manage pain and inflammation in early-stage disease, but patients often continue to experience impaired HRQoL. Thus, there remains a need for new therapies with novel mechanisms that can stop disease progression, potentially reverse damage caused by AxSpA and improve HRQoL in patients with AxSpA. Newer biologic agents, such as those targeting the interleukin 17-interleukin 23 axis, have promising efficacy and may improve HRQoL for patients with AxSpA. The AxSpA has many negative effects on HRQoL. By targeting disease pathways responsible for the development of AxSpA, approved and emerging therapies potentially reduce disease activity and improve the functional status of patients with AxSpA. This narrative review reflects on the findings of studies evaluating HRQoL of individuals with AxSpA and the role of newer therapies.

Antibody-based targeted delivery of interleukin-4 synergizes with dexamethasone for the reduction of inflammation in arthritis

Objectives

We have previously reported that F8-IL4, a fusion protein consisting of the F8 antibody specific to the alternatively-spliced extra domain A of fibronectin and of murine IL-4, cures mice with established arthritis, when used in combination with dexamethasone (DXM). The goal of this study was to assess whether other therapeutic agents, besides DXM, could induce cures in combination with F8-IL4 and to elucidate which leucocytes are most affected by the pharmacological treatment.

Methods

We performed therapy experiments in mice with CIA, using intravenous administrations of F8-IL4 in combination with DXM, MTX, murine cytotoxic T-lymphocyte-associated protein 4 fused to the fragment crystallizable portion of murine IgG2a, as well as mAbs to murine IL17A or the p40 subunit of murine IL12/IL23. Histology and immunohistochemistry for the identification of the various leucocytes were performed on the paws of mice euthanized at different therapy time points.

Results

Only the use of F8-IL4 in combination with DXM induced complete remissions, while all other combinations did not lead to cures. The light microscopical evaluation of paws with arthritis revealed a predominant infiltration of neutrophils, which substantially decreased 24 h after treatment with F8-IL4 and DXM.

Conclusion

The combination of F8-IL4 with DXM promotes a rapid anti-arthritic action by potently inhibiting neutrophil activity. A fully human analogue of F8-IL4 may find clinical utility for the treatment of neutrophil-driven chronic inflammatory conditions.

Juvenile Spondyloarthropathies

Juvenile spondyloarthropathies represent a clinical entity separate from the adult disease. Initial clinical signs of juvenile spondyloarthropathies often include lower extremity arthritis and enthesopathy, without axial involvement at the disease onset. Asymmetrical oligoarthritis of lower extremities is typically seen in this type of arthritis. Enthesopathy, which is the hallmark of the disease, is most commonly seen in the Achilles tendon, being manifested by heel pain. Anterior uveitis and HLA-B27 positivity are seen in a proportion of cases. Sacroiliitis is generally asymptomatic in the pediatric population. Ineffective treatment of childhood disease results in disease progression to typical adult form of ankylosing spondylitis. Therefore, early diagnosis and classification remains one of the most relevant questions in pediatric rheumatology. It should be kept in mind that the disease could be misdiagnosed as FMF or Behçet's syndrome in countries with a high incidence of those conditions. This review revises available classification criteria, clinical manifestations and therapeutic options for patients with juvenile spondyloarthropathies.

Adult Inflammatory Arthritides: What the Radiologist Should Know

Developments and improvements in knowledge are rapid and ongoing in both the radiologic and rheumatologic fields. During the past decade, the roles of imaging and the radiologist in the assessment and management of many inflammatory rheumatologic diseases have undergone several changes. To remain effective in patient care, the radiologist needs to be aware of these changes when recommending and interpreting imaging examinations for the referring physician. The goal of contemporary rheumatoid arthritis (RA) management is to redefine RA as a disease that is no longer characterized by erosions, which reflect established or long-standing untreated disease. Most cases of RA are now diagnosed clinically, but imaging increases diagnostic confidence, is superior to clinical examination for the detection of joint inflammation, and plays an important role in patient management. The concept of the seronegative spondyloarthritides has recently been redefined by the Assessment of SpondyloArthritis International Society (ASAS). This new set of ASAS classification criteria divides the spectrum of spondyloarthritis on the basis of predominantly axial skeletal clinical manifestations or predominantly peripheral skeletal clinical manifestations. For axial spondyloarthritis, magnetic resonance imaging and radiography play crucial roles for classification and diagnosis. For both peripheral spondyloarthritis and psoriatic arthritis, the radiologist can provide important information that influences classification and diagnosis, including documenting radiologic evidence of juxta-articular new bone formation, diagnosing sacroiliitis, or delineating the presence and extent of enthesitis and dactylitis. The radiologist's familiarity with recent classification criteria, in addition to the traditional diagnostic characteristics of the individual inflammatory arthritides, maximizes the productive interface between the radiologist and the rheumatologist. ^©RSNA, 2016.

A systematic review of quality-of-life domains and items relevant to patients with spondyloarthritis

OBJECTIVES

To summarize, from the literature, quality-of-life (QoL) domains and items relevant to patients with spondyloarthritis (SpA), and to determine if commonly used SpA patient-reported outcome (PRO) instruments include the identified domains.

METHODS

We used PRISMA statement for systematic review and searched Medline^® , Embase^®, and PsycInfo^® using relevant keywords. In addition, hand searches of references of the included articles were conducted. All articles were reviewed for inclusion by 2 independent reviewers. QoL domains and items relevant to patients with axial or peripheral SpA were extracted and presented using the adapted World Health Organization Quality-of-Life (WHOQOL) domain framework. SpA PROs were assessed to determine if they included the domains identified.

RESULTS

We retrieved 14,343 articles, of which 34 articles fulfilled inclusion criteria for review. Twenty-five articles were conducted in the European population. Domains such as negative feelings and activities of daily living were found to be present in 28 and 27 articles, respectively. SpA impacted QoL in all domains of the adapted WHOQOL framework. Domains that differed between types of SpA were financial resources, general levels of independence and medication side effects. Embarrassment, self-image, and premature ageing were items that differed by geographical setting. PROs to capture domains for peripheral SpA were similar for axial SpA.

CONCLUSIONS

We found that a wide range of domains and items of QoL were relevant to patients with SpA with minimal differences between patients with axial and peripheral SpA. Clinicians may consider using peripheral SpA PROs to measure QoL of patients with axial SpA.

Evaluation and Management of the Patient With Suspected Inflammatory Spine Disease

Axial spondyloarthritis (AxSpA) is a chronic inflammatory rheumatic disease characterized by inflammatory back pain (IBP) that manifests in childhood, late adolescence, or early adulthood. Ankylosing spondylitis (AS) and nonradiographic AxSpA represent 2 ends of the AxSpA spectrum. Diagnosis can be challenging because patients develop IBP that may not be associated with radiographic changes in the sacroiliac joints. Patients early in the course of disease are estimated to have at least the same level of disease activity and pain as patients with established disease; thus, they could benefit substantially from earlier diagnosis. Although the recent use of magnetic resonance imaging and its inclusion in diagnostic criteria has enhanced the identification of early AxSpA, improvement in early diagnosis has not been consistently reported across all studies. Limited knowledge of the continuum of AxSpA disease manifestations and lack of recognition of IBP in primary practice may contribute to this. Implementing a referral strategy that identifies patients with IBP for additional testing and assessment may lead to better recognition of early signs and symptoms of AxSpA, thereby offering the potential for improved patient outcomes. This review presents an overview of the epidemiology, clinical characteristics, and burdens of AxSpA, followed by a case presentation outlining approaches to the evaluation and management of a patient with suspected inflammatory spine disease.

Low-dose modified-release prednisone in axial spondyloarthritis: 3-month efficacy and tolerability

Background

Oral glucocorticoids (GCs) have been shown to be effective in reducing the inflammatory symptoms of rheumatoid arthritis, but their use is not supported by evidence in spondyloarthritis (SpA). Modified-release (MR) oral prednisone taken at bedtime has been shown to be more effective than immediate-release prednisone taken in the morning. The efficacy of low-dose MR prednisolone in patients with SpA is unknown.

Patients and methods

This single-center cohort study retrospectively assessed the effectiveness and safety of 12-week low-dose MR prednisone (5 mg daily, bedtime administration) in GC-naïve adult patients with symptomatic axial SpA. A 50% improvement of the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) or a final BASDAI score of <4 according to disease activity at baseline was chosen as the primary outcome parameter after MR prednisone.

Results

Fifty-seven patients were evaluated; of them, 41 had an active disease (BASDAI score of ≥4) at baseline. MR prednisone significantly reduced BASDAI (from 5.5±2.6 to 3.0±2.8, P<0.001) as well as inflammatory symptoms, pain, fatigue and morning stiffness. The overall response rate after MR prednisone was 52.6% (53.7% in patients with active SpA and 50.0% in patients with low-active disease; nonsignificant). At multivariable analysis, none of the considered clinical findings independently predicted the response to MR prednisone in subjects with active SpA. Overall, seven patients (11.8%) had nonserious adverse drug reactions after MR prednisone.

Conclusion

In patients with symptomatic SpA and naïve to GCs, low-dose MR prednisone reduced the symptoms and clinical indexes of disease activity and showed a positive safety profile.

Chondrocyte activity is increased in psoriatic arthritis and axial spondyloarthritis

Background

Psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA) are chronic inflammatory rheumatic diseases with complex origins. Both are characterized by altered extracellular matrix remodeling in joints and entheses that results in destructive and osteochondral proliferative lesions. There is a need for biomarkers reflecting core disease pathways for diagnosis and disease mapping. Pro-C2 reflects mature cartilage collagen type IIB formation, while C-Col10 represents turnover of type X collagen, which is exclusively expressed by hypertrophic chondrocytes. The objectives of this study were to study cartilage metabolism in axSpA and PsA by assessing Pro-C2 and C-Col10 and to evaluate their diagnostic utility against a healthy reference population.

Methods

Patients with PsA (n = 101) or axSpA (n = 110) were recruited consecutively from three rheumatology outpatient clinics. Demographic and clinical disease measures were recorded. Pro-C2 and C-Col10 were quantified in serum by using newly developed and specific competitive enzyme-linked immunosorbent assays based on monoclonal antibodies. One-way analysis of variance and Tukey’s multiple comparison tests were performed on log-transformed data. ROC curve analysis was carried out to evaluate their discriminative power.

Results

Pro-C2 levels in serum were significantly increased in both axSpA (median concentration 1.11 ng/ml, 0.67–1.64) and PsA (median concentration 1.03 ng/ml, 0.53–1.47) compared with healthy controls (median concentration 0.30 ng/ml, 0.16–0.41) (p < 0.0001). Pro-C2 did not differ according to treatment. C-Col10 was slightly but equally elevated in the PsA and axSpA groups vs. the control group, but it was significantly lower in patients with axSpA undergoing tumor necrosis factor-α inhibitor (TNFi) treatment. ROC curve analysis revealed AUCs of 0.85 (95 % CI 0.79–0.89) for axSpA and 0.81 (95 % CI 0.75–0.86) for PsA.

Conclusions

These findings indicate that cartilage collagen metabolism was enhanced in the axSpA and PsA groups compared with the healthy control group. The lower C-Col10 level in patients with axSpA undergoing TNFi treatment may reflect that hypertrophic chondrocytes in axSpA are targeted by TNFi. ROC curve analysis showed a diagnostic potential for Pro-C2 in axSpA and PsA.

Looking into the new ASAS classification criteria for axial spondyloarthritis through the other side of the glass

The new concept of axial spondylitis (axSpA) and the Assessment of Spondyloarthritis International Society (ASAS) classification criteria for axSpA have induced new clinical research that has broadened our understanding of spondyloarthritis (SpA) and has had indeed a positive impact on earlier diagnosis and treatment of patients with axSpA who have not yet developed radiographic sacroiliitis. The primary goal of any valid classification criteria for any disease is to provide a homogeneous study population with a common etiopathogenesis, similar prognosis, and similar response to identical treatment. Without such a homogeneous study population, robust clinical and basic science research in any subtype of SpA is not possible. All criteria are dynamic concepts that need updating as our knowledge advances and our review of the ASAS classification criteria of axSpA indicates that complex multi-selection design and unclear (not mutually exclusive) definitions of the imaging and clinical arms of the criteria results in patient heterogeneity across study populations. Therefore, there is a need to improve the validity of the ASAS criteria for axSpA. It is our opinion that in the meantime, the clinically well-established entity of AS, as defined by the modified New York (mNY) criteria, should be preserved for the most accurate comparison of the new research studies with those conducted over the last three decades, and that the use of the ASAS criteria should be restricted to patients with nr-axSpA, who are not recognized by the mNY criteria.

A Neurologist's Guide to TNF Biology and to the Principles behind the Therapeutic Removal of Excess TNF in Disease

Tumor necrosis factor (TNF) is an ancient and widespread cytokine required in small amounts for much physiological function. Higher concentrations are central to innate immunity, but if unchecked this cytokine orchestrates much chronic and acute disease, both infectious and noninfectious. While being a major proinflammatory cytokine, it also controls homeostasis and plasticity in physiological circumstances. For the last decade or so these principles have been shown to apply to the central nervous system as well as the rest of the body. Nevertheless, whereas this approach has been a major success in treating noncerebral disease, its investigation and potential widespread adoption in chronic neurological conditions has inexplicably stalled since the first open trial almost a decade ago. While neuroscience is closely involved with this approach, clinical neurology appears to be reticent in engaging with what it offers patients. Unfortunately, the basic biology of TNF and its relevance to disease is largely outside the traditions of neurology. The purpose of this review is to facilitate lowering communication barriers between the traditional anatomically based medical specialties through recognition of shared disease mechanisms and thus advance the prospects of a large group of patients with neurodegenerative conditions for whom at present little can be done.