Semi-quantitative thigh magnetic resonance imaging scores in assessing disease activity and determining long-term clinical outcome in idiopathic inflammatory myopathies: a causal mediation analysis.

OBJECTIVES: To evaluate the relationship of thigh MRI (t-MRI) with manual muscle testing-8 (MMT-8), muscle enzymes and autoantibodies. To determine the causal and mediating factors resulting in poor recovery of MMT-8 in inflammatory myositis (IIM). METHODS: This was a single-centre retrospective study in IIM patients. t-MRI was semi-quantitatively scored for muscle oedema, fascial oedema, muscle atrophy and fatty infiltration. Spearman correlation of t-MRI scores was done with muscle enzymes at baseline, and MMT-8 at baseline and on follow-up. Causal mediation analysis was performed with age, sex, symptom duration, autoantibodies, diabetes and BMI as independent variables, follow-up MMT-8 as dependent and t-MRI scores as mediating variables. RESULTS: Baseline evaluation was done on 59 and follow-up on 38 patients. Median follow-up of the cohort was 31 (10-57) months. Baseline MMT-8 negatively correlated with muscle oedema (r = -0755), fascial oedema (r = -0.443) and muscle atrophy (r = -0.343). Creatinine kinase (r = 0.422) and aspartate transaminase (r = 0.480) positively correlated with muscle oedema. Follow-up MMT-8 correlated negatively with baseline atrophy (r = -0.497) and fatty infiltration (r = -0.531). On follow-up, MMT-8 males had positive total effect (estimate (95%CI)) via atrophy [2.93 (0.44, 4.89)] and fatty infiltration [2.08 (0.54, 3.71)]. Antisynthetase antibody had a positive total effect via fatty infiltration [4.50 (0.37, 7.59)]. Age had a negative total effect via atrophy [-0.09 (0.19, -0.01)] and fatty infiltration [-0.07 (-0.15, -0.01)]. Disease duration had a negative total effect via fatty infiltration [-0.18 (-0.27, -0.02)]. CONCLUSION: Baseline fatty infiltration and muscle atrophy resulting from older age, female sex, longer disease duration and absent anti-synthetase antibodies, partly mediate muscle recovery in IIM.

Synovial-fluid-derived microparticles express vimentin and GRP78 in their surface and exhibit an in vitro stimulatory effect on fibroblast-like synoviocytes in rheumatoid arthritis.

OBJECTIVES: To investigate the hypothesis that microparticles (MP) may be a source of autoantigens and drive disease progression in rheumatoid arthritis (RA) synovium. METHODS: Synovial fluid (SF) was collected from the knee joints of 41 disease-modifying anti-rheumatic drug-naive RA patients and 30 osteoarthritis (OA) patients. Samples were stained with either anti-vimentin-AlexaFluor-488 or anti-glucose-regulated protein-78-Dylight-488 (GRP78) and Annexin-V-allophycocyanin for flow cytometry analysis. RA and OA fibroblast-like synoviocytes (FLS) were co-cultured with respective SF-derived MP in vitro for 24 h. Supernatant and cell-free SF was assayed for pro-inflammatory analytes by multiplex assays. RESULTS: Elevated percentages of AnnexinV+ Vimentin+ MP (median 0.8, interquartile range [IQR] 1.30) and AnnexinV+ GRP78+ MP (median 0.3, IQR 0.28) were present in RA compared with OA patients. We observed that CXCL6 and CCL8 were secreted in excess by RA-FLS stimulated with RA-SF-MP but not by stimulation with MP-free RA-SF. CONCLUSIONS: Microparticles express vimentin and GRP78 on their surface and stimulate synoviocytes to produce inflammatory molecules, thus sustaining local inflammation in the synovium in RA.

Management of Takayasu arteritis.

This review overviews the challenges in the assessment of disease activity, damage, and therapy of Takayasu arteritis (TAK). Recently developed disease activity scores for TAK are more useful for follow-up visits and require validation of cut-offs for active disease. A validated damage score for TAK is lacking. Computed tomography angiography (CTA), magnetic resonance angiography (MRA), and ultrasound enable the evaluation of vascular anatomy and arterial wall characteristics of TAK. 18-fluorodeoxyglucose (18-FDG) positron emission tomography (PET) visualizes arterial wall metabolic activity and complements the information provided by circulating C-reactive protein (CRP) levels. ESR and CRP alone moderately reflect TAK disease activity. TAK is corticosteroid-responsive but relapses upon tapering corticosteroids. Conventional synthetic disease-modifying anti-rheumatic drugs (DMARDs) are the first-line maintenance agents, and tumor necrosis factor-alpha inhibitors, tocilizumab, or tofacitinib are second-line agents for TAK. Revascularization procedures for TAK should be used judiciously during periods of inactive disease.

Metabolic inflammatory volume and total inflammatory glycolysis: novel parameters to evaluate PET-CT disease activity in Takayasu arteritis.

OBJECTIVES: To evaluate diagnostic accuracy for active Takayasu arteritis (TAK) for two novel 18F-fluorodeoxyglucose PET-CT parameters, the inflammatory volume (MIV) and total inflammatory glycolysis (TIG), to quantitate volume of metabolically-active arterial tissue. METHODS: From a cohort of TAK (n = 36, 35 immunosuppressive-naïve), images of PET-CTs were reviewed for mean and maximum standardized uptake value (SUVmean and SUVmax), target-to-blood pool ratio (TBR), target-to-liver ratio (TLR), and PET Vasculitis Activity Score (PETVAS). Regions of interest were drawn to semiautomatically calculate MIV in areas of 18F-fluorodeoxyglucose uptake ≥ 1.5 SUVmean after excluding physiological tracer uptake. TIG was calculated by multiplying MIV with SUVmean. PET-CT parameters, ESR, CRP, and clinical disease activity scores were compared against the gold standard of physician global assessment of disease activity (PGA, active/inactive). RESULTS: Using dichotomized cut-offs for active TAK at SUVmax (≥ 2.21), SUVmean (≥ 1.58), TBR (≥ 2.31), TLR (≥ 1.22), PETVAS (various cut-offs), ESR (≥ 40 mm/hour), and CRP (≥ 6 mg/L), the novel indices MIV (≥ 1.8) and TIG (≥ 2.7) performed similar [area under the receiver operating characteristics curve (AUC) 0.873 for both] to SUVmax (AUC 0.841) and SUVmean (AUC 0.851), and better than TBR (AUC 0.773), TLR (AUC 0.773), PETVAS [≥ 5.5 (AUC 0.750), ≥ 10 (AUC 0.636), ≥ 15 (AUC 0.546)], ESR (AUC 0.748), or CRP (AUC 0.731). MIV and TIG had similar agreement with PGA or CRP as with SUVmax or SUVmean, and better agreement than TBR, TLR, or PETVAS cut-offs. CONCLUSIONS: MIV and TIG performed similarly, therefore, are viable alternatives to existing PET-CT parameters to assess TAK disease activity in this preliminary report. Key Points • MIV and TIG performed similar to SUVmax and SUVmax for disease activity assessment in TAK. • MIV and TIG distinguished active TAK better than TBR, TLR, PETVAS cut-offs, ESR, or CRP. • MIV and TIG had better agreement with PGA or CRP than TBR, TLR, or PETVAS cut-offs.

Validation of the 2022 American College of Rheumatology/EULAR classification criteria for Takayasu arteritis.

OBJECTIVES: The present study validates the 2022 ACR/European Alliance of Associations for Rheumatology (EULAR) classification criteria for Takayasu's arteritis (TAK), compared with the 1990 ACR TAK classification criteria. METHODS: The fulfilment of 2022 ACR/EULAR and 1990 ACR TAK criteria from four referral centres was assessed for TAK compared with extracranial giant cell arteritis (EC-GCA) and other controls. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratio of a positive test (LR+) or negative test (LR-), and area under receiver operating characteristics curve (AUC) were calculated. RESULTS: Among 504 patients with TAK (404 females) and 222 controls (151 females, 144 patients with EC-GCA), the 2022 ACR/EULAR criteria had better sensitivity (95.83% vs 82.94%) and NPV, but poorer specificity (63.51% vs 90.54%), PPV, LR+, LR- and AUC at the pre-determined cut-offs than the 1990 ACR criteria. The 2022 ACR/EULAR criteria had greater specificity (76.06% vs 57.62%) and AUC (0.845 vs 0.771), with similar sensitivity (93% vs 96.53%) in males as in females. The 2022 ACR/EULAR criteria performed similarly with only EC-GCA as controls (sensitivity 95.83%, specificity 60.42%, AUC 0.781). Sensitivity remained similar, whereas specificity was higher for 40-60 years vs <40 years. Cut-offs of ≥6 (sensitivity 91.87%, specificity 82.88%) and ≥7 (sensitivity 86.71%, specificity 86.49%), or removing the point for female sex (sensitivity 92.64%, specificity 81.08%) greatly improved the balance between sensitivity and specificity. CONCLUSION: The poor specificity of the 2022 ACR/EULAR TAK criteria in real-life settings was improved by increasing the cut-off to 6 or 7, or removing the point for female sex.

Effect of skin phototype on quantitative nailfold capillaroscopy.

Objectives: To determine the impact of Fitzpatrick scale-based skin phototype on visualization of capillary density using nailfold capillaroscopy in healthy Indian adults. Methods: In this cross-sectional study, healthy adults were examined for nailfold capillaroscopy findings utilizing a portable capillary microscope at 800× magnification. Photographs of two contiguous areas measuring 1 mm2 each of the distal row of capillaries were captured. Images were captured from the central area of all fingers except thumb in both hands. Capillary density and morphology of nailfold capillaroscopies were assessed by two blinded assessors. The nailfold capillaroscopy parameters were compared between the Standard Fitzpatrick scale-based skin phototypes. Results: A total of 118 healthy adults were enrolled in the study. Type III, IV, V, and VI skin phototypes were seen in 27 (22.90%), 32 (27.19%), 29 (24.58%), and 30 (25.42%) participants, respectively. All participants (100%) had normal nailfold capillaroscopy morphology and architecture. Zero capillaries were visible in 11 fingers among 5 patients (4.24%) and all of them had Type VI phototype. The median capillary density per mm was 5.19 (interquartile range = 4.37-6.75) with 90 (76.27%) participants having less than seven capillaries. The median average capillary density was significantly different (p-value < 0.0001) across Type III (8.13, interquartile range = 6.44-8.88), Type IV (5.67, interquartile range = 4.41-6.98), Type V (4.94, interquartile range = 4.19-5.38), and Type VI (4.53, interquartile range = 3.72-4.91) phototypes (p < 0.05). Conclusion: The number of capillaries visualized during nailfold capillaroscopy decreases as the skin pigmentation increases. There is a need to redefine the nailfold capillaroscopy density and avascularity by taking skin phototype as one of the determinants before labeling a nailfold capillaroscopy finding with less visualized capillaries as abnormal.

Comparison between leflunomide and sulfasalazine based triple therapy in methotrexate refractory rheumatoid arthritis: an open-label, non-inferiority randomized controlled trial.

To compare efficacy and safety of two different combination csDMARD therapy in Methotrexate-failed Rheumatoid arthritis patients. In this 24-week open-label, parallel-group non-inferiority, single-center clinical trial, Methotrexate-failed Rheumatoid arthritis patients with disease duration < 2 years, were randomized to either of the two treatment regimens-Methotrexate + Leflunomide + Hydroxychloroquine or Methotrexate + Sulfasalazine + Hydroxychloroquine. Primary endpoint was proportion of patients achieving EULAR good response at 12 weeks. Non-inferiority of Leflunomide based therapy was confirmed if the upper limit of the 2-sided 95% confidence interval of treatment difference between the 2 groups was lower than the selected non-inferiority margin of (- 20%) in primary endpoint at 12 weeks. Secondary endpoints were improvement in DAS28, functional outcome and adverse events at 24 weeks. 136 eligible patients were randomized to either Leflunomide or Sulfasalazine group (68 in each group).63 and 59 patients in Leflunomide and 66 and 61 patients in Sulfasalazine group completed 12 and 24 weeks of trial, respectively. In Intension-to-treat analysis, EULAR good response was achieved by 58.8% and 54.4% patients (p = 0.7) at the end of 12 weeks, and 61.7% and 64.7% patients (p = 0.8) at the end of 24 weeks-in Leflunomide and Sulfasalazine group respectively. At 12 weeks, the difference in EULAR good response with 2-sided 95% confidence interval between 2 groups was 4.4% (- 12%, 20%) in intention-to-treat and 5.8% (- 11%, 23%) in perprotocol analysis.15 and 21 adverse events were recorded in Leflunomide and Sulfasalazine group respectively. Parenteral Methotrexate was required more in Sulfasalazine group due to gastrointestinal intolerance. Leflunomide based csDMARD therapy is non-inferior to Sulfasalazine based csDMARD therapy in Methotrexate-failed Rheumatoid arthritis patients with comparable safety profile. Trial registered at clinicaltrials.gov (NCT02930343) dated 10.09.2016.

Spondyloarthritis and the Human Leukocyte Antigen (HLA)-B*27 Connection.

Heritability of Spondyloarthritis (SpA) is highlighted by several familial studies and a high association with the presence of human leukocyte antigen (HLA)-B*27. Though it has been over four decades since the association of HLA-B*27 with SpA was first determined, the pathophysiological roles played by specific HLA-B*27 allotypes are not fully understood. Popular hypotheses include the presentation of arthritogenic peptides, triggering of endoplasmic reticulum (ER) stress by misfolded HLA-B*27, and the interaction between free heavy chains or heavy chain homodimers of HLA-B*27 and immune receptors to drive IL-17 responses. Several non-HLA susceptibility loci have also been identified for SpA, including endoplasmic reticulum aminopeptidases (ERAP) and those related to the IL-23/IL-17 axes. In this review, we summarize clinical aspects of SpA including known characteristics of gut inflammation, enthesitis and new bone formation and the existing models for understanding the association of HLA-B*27 with disease pathogenesis. We also examine newer insights into the biology of HLA class I (HLA-I) proteins and their implications for expanding our understanding of HLA-B*27 contributions to SpA pathogenesis.

Cultural adaptation, translation and validation of Cochin Hand Function Scale and evaluation of hand dysfunction in systemic sclerosis.

OBJECTIVES: Hand dysfunction causes significant reduction in quality of life in systemic sclerosis. We assessed the validity and reliability of the culturally adapted Indian version of Cochin Hand Function Scale (I-CHFS). We determined the factors contributing to hand dysfunction and its burden on quality of life. METHOD: I-CHFS was formulated by replacing five questions (questions 7, 9, 10, 14 and 15) in CHFS which were determined as unsuitable in an Indian setting. The instrument was assessed for acceptability, reliability, reproducibility and validity measures. A total of 87 patients were assessed for various demographic and disease parameters, hand disability and quality of life. RESULTS: The median I-CHFS score was 22(5-54) and 04 (0.5-17.5) among diffuse (dcSSc) and limited cutaneous systemic sclerosis (lcSSc). I-CHFS showed good reproducibility (interclass correlation coefficient = 0.92) and a strong correlation with I-HAQ (rs = 0.832), usual activities EQ-5D-5L (rs = 0.744), self-care EQ-5D-5L (rs = 0.734) and anxiety/depression EQ-5D-5L (rs = 0.729). It had moderate correlation with pain/discomfort EQ-5D-5L (rs = 0.661) and hand HAQ (rs = 0.576) and poor correlation with HAQ-DI (rs = 0.396) and modified Rodnan skin score (rs = 0.390). Finger to table distance, finger to palm distance in extension and limited hand modified Rodnan skin score were significantly associated with higher values of I-CHFS. CONCLUSIONS: Hand dysfunction in systemic sclerosis is substantial and contributes significantly to poor quality of life. The culturally adapted I-CHFS is a valid and reliable tool to assess it and correlated well with the overall disease burden. Key Points • Hand dysfunction is common among systemic sclerosis patients. • Hand dysfunction contributes to the poor quality of life and more disease burden. • Culturally adapted Cochin Hand function Scale helps assess hand dysfunction among Indian scleroderma patients.

Clinical correlates of HLA-B*27 and its subtypes in enthesitis-related arthritis variant of juvenile idiopathic arthritis in south Indian Tamil patients.

AIM: The aim of the study was to assess the distribution of human leukocyte antigen (HLA)-B*27 subtypes and its correlation with disease phenotypes in children with enthesitis-related arthritis variant of juvenile idiopathic arthritis (JIA-ERA). METHOD: One hundred and sixty patients (132 males, 28 females) satisfying the International League Against Rheumatism (ILAR) classification criteria for JIA-ERA were assessed and relevant demographic, clinical and radiographic data were documented. HLA-B*27 typing was done for all the patients and B*27 positive samples were subjected to high-resolution gene sequencing. The effect of duration of illness, HLA-B*27, its subtypes, and gender on the clinical phenotype were analyzed. RESULTS: The mean age of disease onset was 12.69 ± 2.4 years with a male:female ratio of 4.7:1.0. HLA-B*27 was positive in 109/160 patients and HLA-B*27:04 was detected in 63% followed by B*27:05 (30%). Duration of illness was greater in patients with skeletal deformity, hip arthritis, sacroiliitis, cervical spine involvement and acute anterior uveitis (AAU) (P < 0.05). HLA-B*27 positivity was associated with a prolonged course of disease, higher incidence of AAU (14.7% vs 2%, P = 0.015), family history of spondyloarthritis (21.1% vs 5.9%; P = 0.015) and higher erythrocyte sedimentation rate as compared to HLA-B*27 negative patients (P < 0.01). The HLA-B*27:04 and *27:05 positive patients had similar clinical phenotypes. CONCLUSION: Presence of HLA-B*27 and long duration of illness results in skeletal deformity, hip arthritis, sacroiliitis, cervical spine involvement and AAU. HLA-B*27:04 followed by B*27:05 are the most common HLA-B*27 subtypes in our study population and both have a similar clinical phenotype.

Early onset neutropenia and thrombocytopenia following rituximab in lupus nephritis.

Biologics have emerged as an important modality of treatment in rheumatic diseases and have allowed the rheumatologist to explore varied therapeutic uses of these drugs. Rituximab, a monoclonal antibody against CD20 receptor is an important member of the biologic armamentarium for the treatment of various refractory autoimmune inflammatory rheumatic diseases. The drug is now widely used in systemic lupus erythematosus for several complications which are refractory to conventional therapy. Although relatively safe, the post-marketing surveillance of rituximab has revealed a few rare but important adverse reactions. Cytopenia including neutropenia following rituximab, has been vastly reported as a late event (>4 weeks), but a few cases of early onset neutropenia (EON) and thrombocytopenia are also found in the literature. We describe a case of a 35-year-old woman with refractory lupus nephritis who developed asymptomatic EON and thrombocytopenia following rituximab infusion. The neutropenia responded well to granulocyte colony-stimulating factor treatment and the platelets spontaneously recovered. This case report is aimed at highlighting the importance of identifying early onset cytopenia following rituximab which may have an important bearing on the final outcome for the patient.