Diagnostic values and relevant factors of lumbar posterior lesions in axial spondyloarthritis.

OBJECTIVES: To compare the lumbar posterior lesions between axial spondyloarthritis (axSpA) and lumbar disc herniation (LDH) patients, then their diagnostic value and related factors were evaluated. METHODS: This cross-sectional study included axSpA patients from January 2020 to September 2023. They were classified as ankylosing spondylitis (AS) and non-radiographic axSpA (nr-axSpA) individuals. Canada-Denmark (CANDEN) magnetic resonance imaging (MRI) scoring system was used to assess the defects of the lumbar spine. Receiver operating characteristic curve analysis was utilized to determine the value of distinguishing nr-axSpA. Linear regression analyses were adopted to find the relevant factors for lumbar posterior lesions. RESULTS: Ninety-six AS, 98 nr-axSpA, and 108 LDH patients were included. The CANDEN scores were greater in axSpA patients, AS in particular. Furthermore, lumbar posterior lesions can distinguish AS, nr-axSpA, and LDH. Besides, lumbar posterior lesions were positively related to the similar MRI changes in their adjacent structures, but were inversely associated with the other abnormalities. CONCLUSIONS: Lumbar posterior lesions were more serious in axSpA patients. These alterations had value in distinguishing axSpA. Lumbar posterior defects were related to their adjacent components, and they may not fully follow the MRI changing pattern of vertebral bodies and sacroiliac joints.

Clinical characteristics and risk factors associated with bone erosion in patients with tophi.

INTRODUCTION: If a large amount of urate crystals is deposited in a joint cavity for an extended period of time, bone erosion will occur and gradually cause skeletal muscle necrosis and joint deformity. The aim of this study was to describe the clinical characteristics and factors associated with bone erosion in gout patients with tophi. METHODS: A total of 210 gout patients with tophi were enrolled and divided into a bone erosion group (n = 135) and a non-bone erosion group (n = 75). Digital radiography (DR) was performed to detect bone erosion in the elbow, wrist, knee, ankle joints, interphalangeal and metatarsophalangeal joints. The clinical characteristics were recorded and compared between the two groups. Multivariate logistic regression analysis was conducted to explore the factors associated with bone erosion. RESULTS: Compared with the non-bone erosion group, the bone erosion group had an older age, longer disease duration of gout and tophi, higher level of serum creatinine (sCr), higher proportion of drinking history and ulceration, and a lower glomerular filtration rate (GFR). Univariate logistic regression analysis results showed that sex, age, body mass index (BMI), gout duration, tophi duration, GFR, white blood cell (WBC) count, sCr level, smoking history, drinking history, and presence of ulceration were associated with bone destruction. Multivariable logistic regression analysis results indicated that tophi duration, drinking history, ulceration and sCr were positively and independently related to bone erosion. CONCLUSIONS: Tophi patients with bone erosion presented different clinical characteristics. Tophi duration, drinking history, ulceration and sCr were associated with bone erosion in gout patients with tophi.

ILK inhibition reduces osteophyte formation through suppression of osteogenesis in BMSCs via Akt/GSK-3ß/ß-catenin pathway.

BACKGROUND: Osteophyte development is a common characteristic of inflammatory skeletal diseases. Elevated osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) participates in pathological osteogenesis. Integrin-linked kinase (ILK) positively regulates the osteoblastic differentiation of osteoprogenitors, but whether the ILK blockage prevents osteophytes and its potential mechanism is still unknown. Furthermore, the low-dose tumor necrosis factor-α (TNF-α) promotes osteogenic differentiation, but a lack of study reports on the relationship between this cytokine and ILK. OSU-T315 is a small ILK inhibitor, which was used to determine the effect of ILK inhibition on osteogenesis and osteophyte formation. METHODS AND RESULTS: The osteogenesis of BMSCs was evaluated using Alizarin red S staining, alkaline phosphatase, collagen type I alpha 2 chain, and bone gamma-carboxyglutamate protein. The expression and phosphorylation of protein were assessed through western blot. Immunofluorescence was employed to display the distribution of ß-catenin. microCT, hematoxylin-eosin, and safranin O/fast green staining were utilized to observe the osteophyte formation in collagen antibody-induced arthritis mice. We found that ILK blockage significantly declined calcium deposition and osteoblastic markers in a dose- and time-dependent manner. Furthermore, it lowered osteogenesis in the TNF-α-induced inflammatory microenvironment by diminishing the effect of ILK and inactivating the Akt/ GSK-3ß/ ß-catenin pathway. Nuclear ß-catenin was descended by OSU-T315 as well. Finally, the ILK suppression restrained osteophyte formation but not inflammation in vivo. CONCLUSIONS: ILK inhibition lowered osteogenesis in TNF-α-related inflammatory conditions by deactivating the Akt/ GSK-3ß/ ß-catenin pathway. This may be a potential strategy to alleviate osteophyte development in addition to anti-inflammatory treatment.

LncRNA expression profiling in exosomes derived from synovial fluid of patients with rheumatoid arthritis.

OBJECTIVE: To identify the long non-coding RNA (lncRNA) expression profiling in exosomes derived from synovial fluid of rheumatoid arthritis (RA) patients, and carry out bioinformatics analysis on target genes of differentially expressed lncRNAs. METHODS: Exosomes were isolated from synovial fluid via ultracentrifugation. RNAs were extracted from exosomes by using HiPure Liquid RNA/miRNA kits, followed by lncRNA sequencing. Differentially expressed lncRNAs in RA were screened, and bioinformatics analysis of their target genes was carried out. qRT-PCR was used to verify the lncRNA expression levels. RESULTS: Compared with osteoarthritis (OA), 347 lncRNAs were found differentially expressed in RA. Compared with gout, 805 lncRNAs were found differentially expressed in RA. Compared with both OA and gout, 85 lncRNAs were found specially expressed in RA (65 were upregulated (including ENST00000433825.1)). Functional analysis of target genes of the specially expressed lncRNAs revealed significant enrichment of "autophagy" and "mTOR signaling pathway". The qRT-PCR results indicated that ENST00000433825.1 was highly expressed in RA, compared with both OA and gout (P < 0.05), which matched the lncRNA sequencing results. Correlation analysis showed that the level of ENST00000433825.1 in RA patients was significantly and positively correlated with the level of C-reactive protein (CRP) (P < 0.001). CONCLUSIONS: The lncRNA expression profiling in exosomes derived from synovial fluid of RA was significantly different from OA and gout. ENST00000433825.1 was highly and uniquely expressed in RA and significantly and positively correlated with CRP, which might provide a diagnostic and therapeutic biomarker for RA.

Improved Prediction of Knee Osteoarthritis by the Machine Learning Model XGBoost.

Objectives: The accurate prediction of osteoarthritis (OA) severity in patients can be helpful to make the proper decision of intervention. This study aims to build up a powerful model to assess predictive risk factors and severity of knee osteoarthritis (KOA) in the clinical scenario. Methods: A total of 4796 KOA cases and 1205 features were selected by feature selections from the public OA database, Osteoarthritis Initiative (OAI). Six machine learning-based models were constructed and compared for the accuracy of OA prediction. The gradient-boosting decision tree was used to identify important prediction features in the extreme gradient boosting (XGBoost) model. The performance of models was evaluated by F1-score. Results: Twenty features were determined as predictors for KOA risk and severity, including the subject characteristics, knee symptoms/risk factors and physical exam. The XGBoost model demonstrated 100% prediction accuracy for 54.7% of examined samples, and the remaining 45.3% of samples showed Kellgren and Lawrence (KL) gradings very close to the actual levels. It showed the highest prediction accuracy with an F1-score of 0.553 among the tested six models. Conclusions: We demonstrate that the XGBoost is the best model for the prediction of KOA severity in the six examined models. In addition, 20 risk features were determined as the essential predictors of KOA, including the physical exam, knee symptoms/risk factors and subject characteristics, which may be useful for the identification of high-risk KOA cases and for making appropriate treatment decisions as well.

Type I interferon signature and cycling lymphocytes in macrophage activation syndrome.

BACKGROUNDMacrophage activation syndrome (MAS) is a life-threatening complication of Still's disease (SD) characterized by overt immune cell activation and cytokine storm. We aimed to further understand the immunologic landscape of SD and MAS.METHODWe profiled PBMCs from people in a healthy control group and patients with SD with or without MAS using bulk RNA-Seq and single-cell RNA-Seq (scRNA-Seq). We validated and expanded the findings by mass cytometry, flow cytometry, and in vitro studies.RESULTSBulk RNA-Seq of PBMCs from patients with SD-associated MAS revealed strong expression of genes associated with type I interferon (IFN-I) signaling and cell proliferation, in addition to the expected IFN-γ signal, compared with people in the healthy control group and patients with SD without MAS. scRNA-Seq analysis of more than 65,000 total PBMCs confirmed IFN-I and IFN-γ signatures and localized the cell proliferation signature to cycling CD38+HLA-DR+ cells within CD4+ T cell, CD8+ T cell, and NK cell populations. CD38+HLA-DR+ lymphocytes exhibited prominent IFN-γ production, glycolysis, and mTOR signaling. Cell-cell interaction modeling suggested a network linking CD38+HLA-DR+ lymphocytes with monocytes through IFN-γ signaling. Notably, the expansion of CD38+HLA-DR+ lymphocytes in MAS was greater than in other systemic inflammatory conditions in children. In vitro stimulation of PBMCs demonstrated that IFN-I and IL-15 - both elevated in MAS patients - synergistically augmented the generation of CD38+HLA-DR+ lymphocytes, while Janus kinase inhibition mitigated this response.CONCLUSIONMAS associated with SD is characterized by overproduction of IFN-I, which may act in synergy with IL-15 to generate CD38+HLA-DR+ cycling lymphocytes that produce IFN-γ.

Proteomics profiling of CD4 + T-cell-derived exosomes from patients with rheumatoid arthritis.

OBJECTIVES: Our study profiled the CD4 + T-cell-derived exosomes from patients with rheumatoid arthritis (RA) using proteomics. METHODS: Proteomic analysis of CD4 + T-cell-derived exosomes was performed by tandem mass tags (TMT) combined with LC-MS/MS. We validated the most significantly upregulated and downregulated proteins using ELISA and WB. RESULTS: The proteomic results showed that there were 3 upregulated differentially expressed proteins and 31 downregulated differentially expressed proteins in the RA group. The results indicated that dihydropyrimidinase-related protein 3 (DPYSL3) was significantly upregulated in CD4 + T-cell-derived exosomes, whereas proteasome activator complex subunit 1 (PSME1) was significantly downregulated in the RA group. Bioinformatics analysis showed that proteins were enriched in "positive regulation of gene expression", "antigen processing and presentation", "acute-phase response" and "PI3K-AKT signaling" pathways. ELISA verified that compared to the control group, the RA group showed significant upregulation of DPYSL3, and downregulation of PSME1 in CD4 + T-cell-derived exosomes. CONCLUSIONS: The proteomic analysis results of CD4 + T-cell-derived exosomes from patients with RA suggest that these differentially expressed proteins may be involved in RA pathogenesis. DPYSL3 and PSME1 may become useful biomarkers for RA.

Health Care-Seeking Behaviors, Disease Progression, Medications, Knowledge of, and Attitudes Toward Systemic Lupus Erythematosus in China: Cross-sectional Survey Study.

BACKGROUND: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease involving multiple organs throughout the body. The health care-seeking behaviors, disease progression of SLE, and patients' knowledge of and attitudes toward SLE have not been characterized in China. OBJECTIVE: The aim of this study was to depict the health care-seeking behaviors, disease progression, and medications in patients with SLE and to examine the factors associated with their disease flares, knowledge, and attitudes toward SLE in China. METHODS: We conducted a cross-sectional survey in 27 provinces in China. Descriptive statistical methods were used to depict the demographic characteristics, health care-seeking behaviors, medications, and health status. Multivariable logistic regression models were used to identify the factors associated with disease flares, medication changes, and attitudes toward SLE. An ordinal regression model was used to examine the factors associated with the knowledge of the treatment guidelines. RESULTS: We recruited 1509 patients with SLE, and 715 had lupus nephritis (LN). Approximately 39.96% (603/1509) of the patients with SLE were primarily diagnosed with LN, and 12.4% (112/906) developed LN (mean time 5.2 years) from non-LN. Patients whose registered permanent residences or workplaces in other cities from the same province and adjacent provinces seeking health care accounted for 66.9% (569/850) and 48.8% (479/981) of the patients with SLE in the provincial capital cities, respectively. Mycophenolate mofetil was the most commonly used immunosuppressive drug in patients without LN (185/794, 23.3%) and patients with LN (307/715, 42.9%). Femoral head necrosis (71/228, 31.1%) and hypertension (99/229, 43.2%) were the most common adverse event (AE) and chronic disease during treatment, respectively. Change of hospitals for medical consultation (odds ratio [OR] 1.90, 95% CI 1.24-2.90) and development of 1 chronic disease (OR 3.60, 95% CI 2.04-6.24) and AE (OR 2.06, 95% CI 1.46-2.92) and more were associated with disease flares. A pregnancy plan (OR 1.58, 95% CI 1.18-2.13) was associated with changes in medication. Only 242 (16.03%) patients with SLE were familiar with the treatment guidelines, and patients with LN tended to be more familiar with the disease (OR 2.20, 95% CI 1.81-2.68). After receiving treatment, 891 (59.04%) patients changed their attitudes toward SLE from fear to acceptance, and patients with college education or higher (OR 2.09, 95% CI 1.10-4.04) were associated with a positive attitude toward SLE. CONCLUSIONS: A large proportion of patients seeking health care in the provincial capital cities of China migrated from other cities. Persistent monitoring of potential AEs and chronic diseases during SLE treatment and managing patients who changed hospitals for medical consultation are essential for controlling disease flares. Patients had insufficient knowledge about SLE treatment guidelines and would benefit from health education to maintain a positive attitude toward SLE.

mTORC1 links pathology in experimental models of Still's disease and macrophage activation syndrome.

Still's disease is a severe inflammatory syndrome characterized by fever, skin rash and arthritis affecting children and adults. Patients with Still's disease may also develop macrophage activation syndrome, a potentially fatal complication of immune dysregulation resulting in cytokine storm. Here we show that mTORC1 (mechanistic target of rapamycin complex 1) underpins the pathology of Still's disease and macrophage activation syndrome. Single-cell RNA sequencing in a murine model of Still's disease shows preferential activation of mTORC1 in monocytes; both mTOR inhibition and monocyte depletion attenuate disease severity. Transcriptomic data from patients with Still's disease suggest decreased expression of the mTORC1 inhibitors TSC1/TSC2 and an mTORC1 gene signature that strongly correlates with disease activity and treatment response. Unrestricted activation of mTORC1 by Tsc2 deletion in mice is sufficient to trigger a Still's disease-like syndrome, including both inflammatory arthritis and macrophage activation syndrome with hemophagocytosis, a cellular manifestation that is reproduced in human monocytes by CRISPR/Cas-mediated deletion of TSC2. Consistent with this observation, hemophagocytic histiocytes from patients with macrophage activation syndrome display prominent mTORC1 activity. Our study suggests a mechanistic link of mTORC1 to inflammation that connects the pathogenesis of Still's disease and macrophage activation syndrome.

Case Report: Baricitinib as an Alternative in the Maintenance Therapy for Macrophage Activation Syndrome Secondary to Nodular Panniculitis.

Background: Macrophage activation syndrome (MAS) is a severe complication of autoimmune diseases with high mortality. We report the effectiveness of baricitinib as an option for the maintenance therapy in MAS secondary to nodular panniculitis. Case summary: A 24-year-old female came to our hospital with repeated fever and a skin nodule on right tibial tuberosity. Results were notable for raised serum ferritin (SF), triglycerides (TG), elevated liver function enzymes, interleukin-6 (IL-6), interferon-γ (IFN-γ), soluble interleukin-2 receptor (sIL-2R) and decreased activity of NK cells. The pathological biopsy of the subcutaneous nodules indicated nodular panniculitis. Hemophagocytic cells were found in bone marrow aspiration. She was diagnosed as MAS secondary to nodular panniculitis. With the treatment of methylprednisolone (MP) and immunoglobulin, her symptoms and laboratory data gradually improved. Nevertheless, her disease relapsed when the MP dose was tapered. Regarding the usage of JAK inhibitors in MAS, we used baricitinib (JAK1/2 inhibitor) to treat MAS and her symptom and abnormal laboratory findings returned to normal. During follow-up, though the MP dose was tapered, she was stable without a MAS recurrence. Conclusion: The case report suggested baricitinib is an option for MAS in the maintenance therapy phase and is potentially beneficial to prevent recurrence.

TMT-Based Quantitative Proteomics Analysis of Synovial Fluid-Derived Exosomes in Inflammatory Arthritis.

Objectives: To compare the proteomics of synovial fluid (SF)-derived exosomes in rheumatoid arthritis (RA), axial spondyloarthritis (axSpA), gout, and osteoarthritis (OA) patients. Methods: Exosomes were separated from SF by the Exoquick kit combined ultracentrifugation method. Tandem mass tags (TMT)-labeled liquid chromatography mass spectrometry (LC-MS/MS) technology was used to analyze the proteomics of SF-derived exosomes. Volcano plot, hierarchical cluster, gene ontology (GO), and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were conducted. Results: A total of 1,678 credible proteins were detected. Sixty-nine differentially expressed proteins were found in gout, compared with OA, axSpA, and RA simultaneously. Twenty-five proteins were found highly expressed in gout uniquely, lysozyme C and protein S100-A9 included, whose bioinformatic analysis was significantly involved in "neutrophil degranulation" and "prion diseases". Eighty-four differentially expressed proteins were found in axSpA, compared with OA, gout, and RA simultaneously. Thirty-nine proteins were found highly expressed in axSpA uniquely, RNA-binding protein 8A and protein transport protein Sec24C included, whose bioinformatic analysis was significantly involved in "acute-phase response" and "citrate cycle". One hundred and eighty-four differentially expressed proteins were found in RA, compared with OA, gout, and axSpA simultaneously. Twenty-eight proteins were found highly expressed in RA uniquely, pregnancy zone protein (PZP) and stromelysin-1 included, whose bioinformatic analysis was significantly involved in "serine-type endopeptidase inhibitor activity" and "complement and coagulation cascades". Enzyme-linked immunosorbent assay (ELISA) result showed that the exosome-derived PZP level of SF in RA was higher than that in OA (p < 0.05). Conclusion: Our study for the first time described the protein profiles of SF-derived exosomes in RA, axSpA, gout, and OA patients. Some potential biomarkers and hypothetical molecular mechanisms were proposed, which may provide helpful diagnostic and therapeutic insights for inflammatory arthritis (IA).

Evaluation of adalimumab biosimilar candidate (HS016) in Chinese patients with active ankylosing spondylitis based on a health survey: sub-analysis of a phase 3 study.

OBJECTIVE: The equivalence of the biosimilar HS016 to adalimumab (Humira) for the treatment of active ankylosing spondylitis (AS) patients has been previously validated. The aim was to compare the efficacy of HS016 and adalimumab in stratified subgroups at different time points using Health Assessment Questionnaire for Spondyloarthropathies (HAQ-S) and short form 36 (SF-36) questionnaires. METHODS: We carried out a multicenter, randomized, double-blind, parallel, positive control, phase 3 trial of patients with active AS. They were selected randomly to be subcutaneously administered 40 mg HS016 or adalimumab every 2 weeks for a total treatment period of 24 weeks in a 2:1 ratio. A health surveys were used to assess mental and physical improvements of patients as well as other factors. RESULTS: HAQ-S revealed that changes in scores from baseline in both groups were time dependent until 14 weeks and that during the first 4 weeks of treatment the changes declined rapidly. The SF-36 health survey revealed that both HS016 and adalimumab produced rapid beneficial effects against AS during the first 2 weeks of therapy, which gradually declined between 2 and 12 weeks and flattened out after 12 weeks until 24 weeks. CONCLUSION: This trial demonstrated that both HS016 and adalimumab produced rapid improvements in symptoms during the first 2 weeks of treatment. These findings suggest that HS016 is an alternative economical treatment for Chinese AS patients producing a rapid amelioration of symptoms, aiding them to recover their lifestyle satisfaction. TRIAL REGISTRATION: http://www.chictr.org.cn/enindex.aspx , ChiCTR1900022520, retrospectively registered. Key points • HS016 and adalimumab produced rapid AS symptom improvements during the first 2 weeks followed by a slowdown of improvements until week 4 with afterwards few improvements evaluated by HAQ-S • The improvements according to the short form of the 36 (SF-36) questionnaires revealed similar trends as for HAQ-S • There was no significant difference in HAQ-S and SF-36 scores between HS016 and adalimumab.

The relationship between platelet to albumin ratio and disease activity in axial spondyloarthritis patients.

OBJECTIVES: The study aims to investigate the clinical significance of platelet to albumin ratio (PAR), neutrophil to albumin ratio (NAR), and monocyte to albumin ratio (MAR) in axial spondyloarthritis (axSpA). METHODS: Two hundred and ninety-seven axSpA patients and 71 healthy volunteers were recruited. AxSpA patients were divided into inactive group and active group. Spearman's correlation, receiver operating characteristic (ROC) curves, and binary logistic regression analysis were conducted. RESULTS: Albumin was lower in axSpA group, while neutrophil, platelet, monocyte, NAR, PAR, and MAR were higher (p < .05). Albumin was negatively correlated with BASDAI and BASFI (p < .05). Platelet, NAR, PAR, MAR, ESR, and CRP were all positively correlated with BASDAI and BASFI (p < .05). Albumin was lower in axSpA of active group, while platelet, NAR, PAR, MAR, ESR, and CRP were higher (p < .05). ROC curve indicated that the AUC of PAR for axSpA of active group was higher than that of other variables. The optimal cut-off value of PAR was 6.354, with Youden index of 0.337, specificity of 55.4%, and sensitivity of 78.4%. Logistic regression analysis result suggested that PAR was an independent indicator for axSpA disease activity. CONCLUSIONS: PAR had a high diagnostic value for axSpA of active group. PAR was a novel and reliable indicator for axSpA disease activity.

The Diagnostic Value of Synovial Fluid Lymphocytes in Gout Patients.

OBJECTIVE: This study is aimed at investigating the diagnostic value of synovial fluid cell counts in gout patients. METHODS: A total of 185 gout, 64 rheumatoid arthritis (RA), 26 axial spondyloarthritis (axSpA), and 24 osteoarthritis (OA) patients were included in the study. According to serum uric acid (sUA) levels on attack, gout patients were divided into normal sUA gout patients and high sUA gout patients. The laboratory data were recorded. ROC curves were generated to evaluate the diagnostic value of the variables for gout patients and normal sUA gout patients compared with RA, axSpA, and OA patients. RESULTS: The synovial fluid white blood cell (WBC), peripheral blood mononuclear cell (PBMC), monocyte, polymorphonuclear (PMN), and neutrophil counts in gout patients were higher than those in OA patients (P < 0.05). The synovial fluid PBMC and lymphocyte counts in gout patients were lower than those in RA and axSpA patients (P < 0.05). ROC curve results showed that the AUC values of lymphocytes and sUA for gout patients were 0.728 and 0.881, respectively, which were higher than those of other variables. The optimal cutoff value of lymphocytes for gout was 1.362, with a Youden index of 0.439, a sensitivity of 83.3%, and a specificity of 60.6%. The AUC values of lymphocytes, sUA, and CRP for normal sUA gout patients were 0.694, 0.643, and 0.700, respectively, which were higher than those of other variables. The optimal cutoff value of lymphocytes for normal sUA gout patients was 1.362, with a Youden index of 0.422, a sensitivity of 81.6%, and a specificity of 60.6%. CONCLUSIONS: The synovial fluid cell counts of gout patients were different from those of RA, axSpA, and OA patients. Synovial fluid lymphocytes had a higher diagnostic value for gout.

Correlation between C-Reactive Protein to Albumin Ratio and Disease Activity in Patients with Axial Spondyloarthritis.

BACKGROUND: The C-reactive protein (CRP) to albumin (ALB) ratio (CAR) has emerged as a novel inflammatory biomarker. This study was designed to investigate the role of CAR in the disease activity of axial spondyloarthritis (axSpA). METHODS: A total of 241 patients and 61 healthy controls were retrospectively enrolled in this study. AxSpA patients were further divided into the inactive group (n = 176) and active group (n = 65) according to Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) cutoff value of 4. Laboratory data and clinical assessment indices were recorded. Spearman's correlation analysis, receiver operation characteristic (ROC) curve analysis, and binary logistic regression analysis were performed. RESULTS: In axSpA patients, CAR was significantly higher than the healthy group (P < 0.001). Similarly, axSpA patients in the active group had higher CAR than the inactive group (P < 0.001). Besides, CAR was positively correlated with erythrocyte sedimentation rate (ESR) (r = 0.704, P < 0.001), CRP (r = 0.996, P < 0.001), BASDAI (r = 0.329, P < 0.001), and Bath Ankylosing Spondylitis Functional Index (BASFI) (r = 0.330, P < 0.001). ROC curve analysis suggested that the area under the curve (AUC) of CAR for axSpA of the active group was 0.701, which was higher than that of CRP and ESR. The optimal cutoff point of CAR for axSpA of the active group was 0.3644, with a sensitivity and specificity of 58.5% and 79.0%. Binary logistic analysis results revealed that CAR was an independent predictive factor for axSpA disease activity (odds ratio = 4.673, 95% CI: 1.423-15.348, P = 0.011). CONCLUSIONS: CAR was increased in axSpA and axSpA of the active group. CAR may be a novel and reliable indicator for axSpA disease activity.

Lumbar Disc Herniation is a Nonnegligible Factor for the Degeneration of Sacroiliac Joints.

BACKGROUND: Sacroiliac joint (SIJ) abnormality is a potential source of low back pain (LBP), therefore numerous patients receive various treatments because of the degenerative changes of SIJ. However, the outcome is unfavorable for patients because these morphologic alterations are common but not the origins of LBP. Previous studies revealed lumbar fusion and transitional vertebra increased the prevalence of degeneration of SIJ. Lumbar disc herniation (LDH) is one of the most common lumbar diseases, but there is no study regarding the relationship between LDH and SIJ degradation. OBJECTIVES: The aim of this study was to investigate the severity of SIJ degeneration in patients with LBP with LDH. The relationship between degenerative changes of SIJ and LDH was also assessed. STUDY DESIGN: Retrospective observational study. SETTING: This study was conducted in 2 medical centers located in southeast and midwest China, respectively. METHODS: Lumbar and pelvic computed tomography (CT) scans of patients with LDH (LDH group) from January 2016 to May 2020 were reviewed using a picture archiving and communication system. The control group was age, gender, and body mass index-matched patients with LBP without LDH. Patients underwent whole abdomen and pelvic CT examinations due to non-musculoskeletal disorders. Scores of SIJ degeneration were compared between patients with LDH and the control group. Differences in SIJ degeneration among patients with LDH with diverse characteristics, symptoms, and complications were also evaluated. Univariate and multivariate linear mixed model (LMM) was chosen to identify the factors associated with SIJ degeneration. RESULTS: CT examinations of 782 patients with LDH were assessed, whereas 223 patients were in the control group. The SIJ degeneration score of the LDH group and control group were 6.00 (5.00) and 3.00 (4.00) (P < 0.05). Age and whether patients suffered from LDH were included in the LMM, which involved all reviewed patients (P < 0.05). Regarding the characteristics of LDH, the patients with more herniated discs had more severe SIJ degeneration. The score of SIJ degradation in patients with upper LDH was significantly higher than the other patients with LDH (12.00 [4.00] vs. 6.00 [4.00]; P < 0.05). Similarly, more significant SIJ degeneration was observed in patients with LDH who had secondary lumbar spinal stenosis (10.00 [4.00] vs. 5.00 [4.00]; P < 0.05). The scores of SIJ degradation were significantly greater in patients with LDH with sciatica, numbness, weakness, and/or cauda equina syndrome. Age and LDH were identified as associated factors for more serious degeneration of SIJ among patients with LDH. LIMITATIONS: The main limitation of this study was the retrospective observational nature. Hence our study described that SIJ degeneration was relevant to LDH, but the causal relationship was uncertain. Magnetic resonance imaging was not chosen in this study. CONCLUSIONS: The SIJ degeneration in patients with LDH was more serious than in individuals without LDH. SIJ degeneration was more significant in patients with LDH with more pathological alterations, symptoms, and complications. Age and LDH relate to SIJ degeneration. Therefore the diagnosis and selection of treatment for SIJ changes should comprehensively consider the coexistence of LDH.

Serum metabolic profiling analysis of gout patients based on UPLC-Q-TOF/MS.

BACKGROUND: Gout is a common kind of inflammatory arthritis with metabolic disorders. However, the detailed pathogenesis of gout is complex and not fully clear. We investigated the serum metabolic profiling of gout patients by ultra-performance liquid chromatograph quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). METHODS: Serum metabolites were extracted from 31 gout patients and 31 healthy controls. Metabolite extracts were analyzed in negative mode by UPLC-Q-TOF/MS for global metabolomics. Principal components analysis (PCA), orthogonal partial least squares-discriminant analysis (OPLS-DA) and hierarchical clustering analysis were performed to detect different compounds between the two groups. Receiver operating characteristic (ROC) curve analysis and pathway analysis of the different metabolites were conducted. RESULTS: A total of 9192 compounds were detected, of which 138 significantly different compounds were selected, according to the criteria of (Variable importance in projection (VIP) > 3). Hierarchical clustering analysis showed that the relative levels of the differential compounds were different between the 2 groups. Ninety-one reliable metabolites matching the human metabolome database (HMDB) were confirmed. ROC curve results revealed that 4-hydroxytriazolam, urate and bilirubin exerted higher AUC values. Pathway analysis indicated that the significantly different metabolites were mainly involved in primary bile acid biosynthesis, purine metabolism and glycerophospholipid metabolism. CONCLUSIONS: The serum metabolic profiling of gout patients was significantly different from healthy subjects based on UPLC-Q-TOF/MS. Bilirubin was the potential biomarker. Primary bile acid biosynthesis may be a novel metabolic pathway of gout.