Our data demonstrate that priming of human neutrophils with TNF-α promotes uric acid-mediated IL-1β secretion in the absence of microbial stimulation. These findings provide insights into the neutrophils-mediated inflammatory processes in gouty arthritis.

Background HLA-DRB1 alleles are major determinants of genetic predisposition to rheumatic diseases. We assessed whether DRB1 alleles are associated with susceptibility to particular clinical features of adult onset Still’s disease (AOSD) in a Japanese population by determining the DRB1 allele distributions.Methods DRB1 genotyping of 96 patients with AOSD and 1,026 healthy controls was performed. Genomic DNA samples from the AOSD patients were also genotyped for MEFV exons 1, 2, 3, and 10 by direct sequencing.ResultsIn Japanese patients with AOSD, we observed a predisposing association of DRB1*15:01 (p = 8.60 × 10−6, corrected p (Pc) = 0.0002, odds ratio (OR) = 3.04, 95% confidence interval (95% CI) = 1.91–4.84) and DR5 serological group (p = 0.0006, OR = 2.39, 95% CI = 1.49–3.83) and a protective association of DRB1*09:01 (p = 0.0004, Pc = 0.0110, OR = 0.34, 95% CI = 0.18–0.66) with AOSD, and amino acid residues 86 and 98 of the DRβ chain were protectively associated with AOSD. MEFV variants were identified in 49 patients with AOSD (56.3%). The predisposing effect of DR5 was confirmed only in patients with AOSD who had MEFV variants and not in those without MEFV variants. Additionally, DR5 in patients with AOSD are associated with macrophage activation syndrome (MAS) and steroid pulse therapy.ConclusionThe DRB1*15:01 and DR5 are both associated with AOSD susceptibility in Japanese subjects. A protective association between the DRB1*09:01 allele and AOSD was also observed in these patients. Our data also highlight the effects of DRB1 alleles in susceptibility to AOSD.Electronic supplementary materialThe online version of this article (doi:10.1186/s13075-017-1406-x) contains supplementary material, which is available to authorized users.

Autoantibodies to triosephosphate isomerase (TPI), which is an important glycolytic enzyme in red blood cells and neuronal cells, have been reported to be associated with neuropsychiatric systemic lupus erythematosus (NPSLE) pathogenesis. However, the clinical features regarding anti-TPI antibody (anti-TPI)-positive NPSLE are not yet known. The aim of this study is to investigate the clinical features of anti-TPI-positive NPSLE patients using anti-TPI index values determined by enzyme-linked immunosorbent assay (ELISA). Thirty-one NPSLE patients treated in our department were included in this study. Serum samples were collected, and serum anti-TPI titers were measured by ELISA. The anti-TPI index values were defined as follows: (OD of samples - OD of negative control)/(OD of positive control - OD of negative control) × 100. Anti-TPI index values greater than 2 standard deviations above the mean of healthy controls were regarded as positive. The clinical features of anti-TPI-positive and anti-TPI-negative NPSLE were compared. Ten of the 31 NPSLE patients had anti-TPI positivity (32.3%). The clinical features of anti-TPI-positive NPSLE were comparable with those of anti-TPI-negative NPSLE, except for a higher frequency of aseptic meningitis (p = 0.027) and a lower frequency of acute confusional state (P = 0.026). Laboratory data in patients with anti-TPI-positive NPSLE showed significantly higher serum IgG levels. Furthermore, anti-TPI index values positively correlated with serum IgG levels. Our study indicates that serum anti-TPI increases in the presence of elevated IgG levels and can be associated with the pathogenesis of aseptic meningitis in NPSLE.

Anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive clinically amyopathic dermatomyositis (CADM) is frequently associated with rapidly progressive interstitial lung disease (RP-ILD) resulting in high mortality. Here we report a 51-year-old Japanese woman with anti-MDA5 antibody-positive hypomyopathic dermatomyositis (DM) who developed RP-ILD. She developed respiratory failure and pneumomediastinum, however her RP-ILD responded favorably to the combined immunosuppressive treatments consisting of steroids, intravenous cyclophosphamide and tacrolimus. She was complicated with severe infections, which were successfully managed by combined modality therapy including artificial ventilation and antibiotics in addition to immunosuppressive treatments in parallel to the decline of anti-MDA5 antibody titer (>150 Index to 75 Index). She was discharged after 6 months of treatment without any respiratory sequelae. Hypomyopathic DM patients with high titers of anti-MDA5 antibody should be treated with aggressive immunosuppressive therapies and closely monitored to prevent various infections.

Introduction:Multicentric reticulohistiocytosis (MRH) is a rare histiocytic disorder that involves the skin, joints, and visceral organs.Case presentation:We report a 67-year-old woman with MRH who presented with a 2-years history of polyarthralgia and skin nodules. Her symptoms were an inflammatory polyarthropathy with punched-out lesions of the distal interphalangeal (DIP) joints of both hands. Doppler ultrasonography of the hands showed large bone erosions with power Doppler signals in the DIP joints. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) demonstrated increased FDG uptake in cutaneous papules surrounding the affected joints, suggesting an inflammatory process. There was no evidence of malignancy. Biopsy samples of skin nodules exhibited dermal infiltration with CD68-positive histiocytes and multinucleated giant cells. The patient was diagnosed with MRH and treated with combination therapy comprising a steroid (prednisolone), tacrolimus, methotrexate, and infliximab, which resulted in clinical improvement. Following infliximab treatment, there was a significant decrease in a bone resorption marker (tartrate-resistant acid phosphatase 5b: TRACP-5b), suggesting that tumor necrosis factor-α targeting therapy may inhibit osteoclast formation and resorption activity in patients with MRH.Conclusion:MRH is a progressive destructive arthritic condition, and early diagnostic and therapeutic strategies are necessary to improve the outcome. FDG-PET/CT and joint ultrasonography might be noninvasive imaging modalities that could help diagnose MRH.