Pulmonary cryptococcosis suspected due to inhalation of swallow excreta presenting with multiple infiltrative shadows.

A 70-year-old woman had been treated with methotrexate for rheumatoid arthritis by a rheumatologist who opened a clinic near our hospital. In January of a certain year, she had respiratory symptoms of cough, sputum, and fever. Laboratory test results showed a white blood cell count of 8600/µL (neutrophil count of 5330/µL, lymphocyte count of 2490 µ/L), C-reactive protein (CRP) of 3.30 mg/dL. Chest radiography showed multiple infiltrative shadows in the right middle and lower lobes. Bronchoalveolar lavage fluid (BAL) lymphocyte count was increased (65.1%), and histopathological findings were consistent with numerous bowl-shaped cryptococcus cells stained black by Grocott staining. Added measurement of serum cryptococcal antigen titers was 4096-fold. Treatment with fluconazole 400 mg/day was initiated, and her symptoms resolved; the shadows of the lung fields improved. When asked in detail, the cryptococcus infection route was suspected from swallow excreta. There have been no reported cases of pulmonary cryptococcosis suspected due to inhalation of swallow excreta presenting with multiple infiltrative shadows.

Real-world effectiveness of a single conventional disease-modifying anti-rheumatic drug (cDMARD) plus an anti-TNF agent versus multiple cDMARDs in rheumatoid arthritis: a prospective observational study.

Objective: The objective of this prospective, observational multicenter study (NCT03264703) was to compare the effectiveness of single conventional disease-modifying anti-rheumatic drug (cDMARD) plus anti-tumor necrosis factor (TNF) therapy versus multiple cDMARD treatments in patients with moderate-to-severe rheumatoid arthritis (RA) following cDMARD failure in the real-world setting in South Korea. Methods: At the treating physicians' discretion, patients received single cDMARD plus anti-TNF therapy or multiple cDMARDs. Changes from baseline in disease activity score 28-joint count with erythrocyte sedimentation rate (DAS28-ESR), corticosteroid use, and Korean Health Assessment Questionnaire (KHAQ-20) scores were evaluated at 3, 6, and 12 months. Results: Of 207 enrollees, the final analysis included 45 of 73 cDMARD plus anti-TNF and 91 of 134 multiple-cDMARD recipients. There were no significant between-group differences (BGDs) in ANCOVA-adjusted changes from baseline in DAS28-ESR at 3, 6 (primary endpoint), and 12 months (BGDs -0.18, -0.38, and -0.03, respectively). More cDMARD plus anti-TNF than multiple-cDMARD recipients achieved a >50% reduction from baseline in corticosteroid dosage at 12 months (35.7% vs 14.6%; p=0.007). Changes from baseline in KHAQ-20 scores at 3, 6, and 12 months were significantly better with cDMARD plus anti-TNF therapy than with multiple cDMARDs (BGD -0.18, -0.19, and -0.19 points, respectively; all p≤0.024). Conclusion: In the real-world setting, relative to multiple cDMARDs, single cDMARD plus anti-TNF therapy significantly improved quality-of-life scores and reduced corticosteroid use, with no significant BGD in disease activity, in RA patients in whom previous cDMARD therapy had failed.

Treatment of Posterior Hip Dislocation due to Juvenile Idiopathic Arthritis. Report of Two Cases.

Introduction: Juvenile idiopathic arthritis ( JIA) is a persistent autoimmune-inflammatory disease that affects children younger than 16. Aggressive synovitis of the hip may cause joint destruction, hip protrusion, erosion, pseudosubluxation, dysplasia, and osteoarthritis. Subluxation of the hip had been reported previously. However, dislocation of the hip in JIA is an extremely rare situation, and only two cases have been reported up to date. Reduction of the dislocated hip has to be performed in any way. However, there is no algorithm to be followed for the treatment of hip dislocations caused by JIA. Case Presentation: In this study, we presented two cases of hip dislocation caused by JIA.Case 1: An 11-year-old boy had JIA and chronic recurrent multifocal osteomyelitis (CRMO). X-rays and computed tomography (CT) revealed a posterior dislocation of the left hip. An urgent operation was planned for the reduction of the hip. Avascular necrosis, dysplasia, or erosions were not evident at the last follow-up.Case 2: An 11-year-old girl was referred to the hospital with excessive left hip pain starting 24 h ago. A limited synovectomy with joint irrigation was performed. However, pathological examination of the synovium showed chronic inflammation consistent with JIA. On the post-operative 10th day, the patient was consulted for an increase in hip pain and deformity of the left hip. X-rays and MRI revealed posterior dislocation of the left hip with synovial hypertrophy. An urgent operation was planned. The hip could be reduced under anesthesia with mild traction, and a pelvipedal cast was applied only for 3 weeks. Avascular necrosis, dysplasia, destruction, or erosions were not evident at the last follow-up. Conclusion: For early diagnosed patient reduction under anesthesia and medial soft-tissue contracture release; for late diagnosed patient medial soft-tissue contracture release, capsulotomy and synovectomy were effective to prevent destruction and early degenerative changes of the hip joint for treatment of dislocation caused by JIA.

Bowel-Associated Dermatosis-Arthritis Syndrome: A Case Report.

Introduction: Gastric bypass surgery is an effective surgical intervention for morbid obesity. However, it is not without risk. Gastric bypass surgery may produce malabsorptive or surgical complications, which can result in nutritional deficiencies as well as syndromes related to bacterial overgrowth in the blind loops of the bowel. Case Presentation: Severe nutritional deficiencies may occur due to patient noncompliance with the prescribed regimen, or arise secondary to malabsorptive or mechanical surgical complications. We describe a case of a 37-year-old female who underwent gastric bypass surgery and experienced a recalcitrant eczematous eruption with sporadic subcutaneous, purulent nodules which completely resolved after the reversal of her bariatric procedure. Conclusion: Since 2001, the number of morbidly obese patients who have undergone bariatric surgery has been increasing. As a result, clinicians can expect to more frequently encounter complications that can result from these procedures.

Role of macrophages and their exosomes in orthopedic diseases.

Exosomes are vesicles with a lipid bilayer structure that carry various active substances, such as proteins, DNA, non-coding RNA, and nucleic acids; these participate in the immune response, tissue formation, and cell communication. Owing to their low immunogenicity, exosomes play a key role in regulating the skeletal immune environment. Macrophages are important immune cells that swallow various cellular and tissue fragments. M1-like and M2-like macrophages differentiate to play pro-inflammatory, anti-inflammatory, and repair roles following stimulation. In recent years, the increase in the population base and the aging of the population have led to a gradual rise in orthopedic diseases, placing a heavy burden on the social medical system and making it urgent to find effective solutions. Macrophages and their exosomes have been demonstrated to be closely associated with the pathogenesis and prognosis of orthopedic diseases. An in-depth understanding of their mechanisms of action and the interaction between them will be helpful for the future clinical treatment of orthopedic diseases. This review focuses on the mechanisms of action, diagnosis, and treatment of orthopedic diseases involving macrophages and their exosomes, including fracture healing, diabetic bone damage, osteosarcoma, and rheumatoid arthritis. In addition, we discuss the prospects and major challenges faced by macrophages and their exosomes in clinical practice.

A bibliometric analysis of miRNAs in rheumatoid arthritis from 2001 to 2022: Research hotspots and trends.

BACKGROUND: MicroRNAs (miRNAs) are widely recognized in the pathogenesis of autoimmune disease. As a key regulatory factor, miRNAs have introduced new biomarkers for the early diagnosis of rheumatoid arthritis (RA) and provided a favorable research direction for the development of novel therapeutic targets. This study aimed to explore the hotspots of miRNA research related to RA published from different countries, organizations, and authors. METHODS: From 2001 to 2022, publications on miRNA related to RA were identified in the Web of Science database. The total and annual number of publishments, citations, impact factor, H-index, productive authors, and involved journals were collected for quantitative and qualitative comparisons. RESULTS: A total of 29 countries/regions in the world have participated in the research of miRNAs and RA over the past two decades, and China (760, 53.18%) and the United States (233, 16.31%) account for the majority of the total publications. China dominated in total citation (17881) and H-index (62). A total of 507 academic journals have published articles in related fields, and Frontiers in Immunology published the most (53, 3.71%). Chih-hsin Tang of the China Medical University has published the most papers (16, 1.2%). Stanczyk (2008) published the most cited article Altered expression of miRNAs in synovial fibroblasts and synovial tissue in rheumatoid arthritis in Arthritis and Rheumatism, with 660 citations. Inflammation is the high-frequency keyword outside of RA and miRNAs, and related researches have mainly focused on miR-146a and miR-155. CONCLUSIONS: In the past two decades, extensive and continuous research has been conducted to investigate the role of miRNAs in RA, and miRNAs are widely recognized in the pathogenesis of RA. Related research has mainly focused on miR-146a and miR-155 that have shown promising results as key factors in RA experimental models. Focusing on clinical applications and translational research may be the future research direction and hotspot based on molecular biology basic research and mechanism exploration.

Reliability assessment of the OMERACT whole-body magnetic resonance imaging scoring system for juvenile idiopathic arthritis.

Inter-reader reliability of a new scoring system for evaluating joint inflammation and enthesitis in whole body MRI (WBMRI) in juvenile idiopathic arthritis was tested. The scoring system grades 732 item-region combinations of bone marrow and soft tissue changes for commonly involved joints and entheseal sites. Five radiologists rated 17 WBMRI scans through an online rating platform. Item-wise reliability was calculated for 117 items with non-zero scores in >10 % of readings. Interquartile ranges of the five-reader Kappa reliability coefficients were 0.58-0.73 (range: 0.36-0.88) for the joints, 0.65-0.81 (range: 0.39-0.95) for the entheses, and 0.62-0.75 (range: 0.60-0.76) for chronic nonbacterial osteomyelitis-like lesions.

Elevated levels of anti-Golgi antibodies: An early sign of seronegative rheumatoid arthritis.

Anti-Golgi antibodies are uncommon antibodies that exhibit specific, polarized cytoplasmic staining on the Hep-2 substrate. The objective of our study was to identify the clinical and laboratory features associated with anti-Golgi antibodies. We examined 4.5 years of data from a Turkish tertiary hospital in this retrospective cohort analysis. The indirect immunofluorescence staining patterns, antinuclear antibody (ANA) titres and clinical data of all patients were obtained from the hospital record system. A total of 146,055 ANAs were detected, of which 224 patients (0.15%) exhibited anti-Golgi antibody staining. In total, 39.4% of diagnosed patients had autoimmune diseases (AIDs). Of the AIDs, 26 (46.4%) were rheumatoid arthritis (RA). This is a very high rate and another remarkable point is that 17 (65.3%) of these patients had seronegative RA. High-titre results (1 ≥ 1/320) were more common in patients with AID. Anti-Ro52 was prevalent in 50% of extractable nuclear antigen (ENA)-positive patients, making it a remarkable finding. The majority of individuals with high-titre anti-Golgi antibodies had AID, particularly RA. The majority of these patients also tested negative for anti-cyclic citrullinated peptide (anti-CCP) and rheumatoid factor (RF). Finally, high-titre anti-Golgi antibodies may be an important serologic marker for seronegative RA in the Turkish population.

Pharmacogenetic Basis of Response Fluctuations to Methotrexate in Rheumatoid Arthritis: A Narrative Review.

Rheumatoid arthritis is a crippling autoimmune disease affecting more than 18 million people worldwide and thus becoming one of the important contributors to the global health burden. The majority of the affected are females, especially those above the age of 50, but males and younger adults are equally vulnerable. It is a constellation of genetic and environmental factors that interplay to manifest the joint deformities and disabilities that are the hallmarks of this disease. Painkillers are used alongside disease-modifying anti-rheumatic drugs to minimize the patient's agony and also to halt the progression of the disease. Worldwide, methotrexate is recommended as the first-line drug, but unexpected resistance is encountered in a significant number of patients. This review summarizes the pathophysiology, clinical findings, and therapeutic strategies for rheumatoid with a focus on research studies performed to establish a genetic basis for response fluctuations of methotrexate across different population groups.

Asymptomatic intraspinal epidermoid cyst in a 7-year-old male with juvenile idiopathic arthritis identified by an advanced physiotherapist practitioner: a case report.

BACKGROUND: Pediatric intraspinal epidermoid cysts are rare with potential to cause life-altering outcomes if not addressed. Reports to date describe symptomatic presentations including loss of bladder or bowel function and motor and sensory losses. This case report identifies the diagnostic challenge of an asymptomatic intraspinal epidermoid cyst in the cauda equina region presenting in a 7-year-old male with juvenile idiopathic arthritis (JIA). DIAGNOSIS: An advanced physiotherapist practitioner assessed and diagnosed a previously healthy 7-year-old-male of South Asian descent with JIA based on persistent knee joint effusions. Complicating factors delayed the investigation of abnormal functional movement patterns, spinal and hip rigidity and severe restriction of straight leg raise, all atypical for JIA. Further delaying the diagnosis was the lack of subjective complaints including no pain, no reported functional deficits, and no neurologic symptoms. A spinal MRI investigation 10-months from initial appointment identified intraspinal epidermoid cysts occupying the cauda equina region requiring urgent referral to neurosurgery. DISCUSSION: Clinical characteristics and pattern recognition are essential for diagnosing spinal conditions in pediatric populations. Diagnostic challenges present in this case included co-morbidity (JIA), a severe adverse reaction to treatment, a lack of subjective complaints and a very low prevalence of intraspinal epidermoid cysts. IMPACT STATEMENTS: Early signs of pediatric asymptomatic intraspinal epidermoid cysts included abnormal functional movement patterns, rigidity of spine, severely limited straight leg raise and hip flexion without pain. Advanced physiotherapist practitioners can be integral to pediatric rheumatology teams considering their basic knowledge in musculoskeletal examination and functional mobility assessment when identifying rare spinal conditions that present within the complex context of rheumatic diseases.

AA Amyloidosis: A Contemporary View.

PURPOSE OF REVIEW: Amyloid A (AA) amyloidosis is an organ- or life-threatening complication of chronic inflammatory disorders. Here, we review the epidemiology, causes, pathogenesis, clinical features, and diagnostic and therapeutic strategies of AA amyloidosis. RECENT FINDINGS: The incidence of AA amyloidosis has declined due to better treatment of the underlying diseases. Histopathological examination is the gold standard of diagnosis, but magnetic resonance imaging can be used to detect cardiac involvement. There is yet no treatment option for the clearance of amyloid fibril deposits; therefore, the management strategy primarily aims to reduce serum amyloid A protein. Anti-inflammatory biologic agents have drastically expanded our therapeutic armamentarium. Kidney transplantation is preferred in patients with kidney failure, and the recurrence of amyloidosis in the allograft has become rare as transplant recipients have started to benefit from the new agents. The management of AA amyloidosis has been considerably changed over the recent years due to the novel therapeutic options aiming to control inflammatory activity. New agents capable of clearing amyloid deposits from the tissues are still needed.

[Current data on rheumatological care: annual report from the National database (NDB) of the regional collaborative arthritis centres in Germany]. / Aktuelle Zahlen zur rheumatologischen Versorgung ­ Jahresbericht aus der Kerndokumentation der regionalen kooperativen Rheumazentren.

In the National database (NDB) of the German regional collaborative arthritis centres, annual data on the rheumatological care of patients with inflammatory rheumatic diseases have been collected since 1993. This first annual report presents current cross-sectional data on medication and patient-reported outcomes gathered in 2022.

How Does Ultrasound Global OMERACT-EULAR Synovitis Score (GLOESS) for Rheumatoid Arthritis (RA) Activity Assessment Perform in Real-Life?

OBJECTIVE: This study aimed to assess the effectiveness of the Global OMERACT-EULAR Synovitis Score (GLOESS) of bilateral second to fifth metacarpophalangeal joints (MCP 2-5) in evaluating rheumatoid arthritis (RA) activity in a real-life setting. METHODS: This cross-sectional study included consecutive RA patients without hyperalgesia. Clinical data were extracted from electronic medical records. Evaluations were conducted on bilateral MCP 2-5 by two independent experts in musculoskeletal ultrasound (MSUS). Correlation between clinical and ultrasonographic parameters was analyzed, aiming to define a cutoff value for detecting disease activity. RESULTS: Sixty-nine patients were included. The mean DAS28-ESR was 4.3 (±1.4), and the median GLOESS was 7 (13). The correlation between GLOESS and DAS28 was moderate (r = .62; P < .05). A total GLOESS score of ≤3 and all joints with both GS and PD ≤1 showed good sensitivity and specificity for detecting disease activity (remission/low vs moderate/high, P = 0). CONCLUSION: In a real-life scenario, GLOESS for MCP 2-5 emerges as a valuable measure of RA activity. The optimal cutoff distinguishing remission/low from moderate/high disease activity was determined to be GLOESS ≤3, with all MCP joints exhibiting both GS and PD scores of ≤1.

Long-term clinical outcomes in early rheumatoid arthritis that was treated-to-target in the BeSt and IMPROVED studies.

OBJECTIVES: To assess disease outcomes after 20 and 12 years of patients with rheumatoid (RA) or undifferentiated arthritis (UA), treated-to-target in the BeSt and IMPROVED trials. METHODS: In BeSt (inclusion 2000-2002, duration 10 years), 508 patients with early RA were randomized to: 1. sequential monotherapy, 2. step-up combination therapy, 3. initial csDMARD combination therapy, 4. initial bDMARD/csDMARD combination therapy. The treatment target was low disease activity (DAS ≤ 2.4).In IMPROVED (inclusion 2007-2010, duration 5 years), 610 patients with early RA/UA started MTX with prednisone bridging. The treatment target was remission (DAS < 1.6). Patients not in early remission were randomized to 1. csDMARD combination therapy or 2. bDMARD/csDMARD combination therapy.Between 2019-2022, these patients were invited for long-term follow-up. RESULTS: One-hundred-fifty-three ex-Best and 282 ex-IMPROVED patients participated in the follow-up study after median 12 and 20 years since study start.In ex-BeSt and ex-IMPROVED patients the rate of low disease activity was 91%, and 68% were in DAS remission. Median SHS was 14.0 in ex-BeSt (IQR 6.0-32.5; progression since end BeSt 6.0, IQR 2.0-12.5) and 8 in ex-IMPROVED participants (IQR 3-16; progression since end IMPROVED 4, IQR 2-9). Mean HAQ was 0.8 ± 0.6 in ex-BeSt (change since end BeSt: 0.3 ± 0.5) and 0.6 ± 0.6 in ex-IMPROVED participants (change since end IMPROVED: 0.06 ± 0.5). CONCLUSION: At 12/20 years after treatment start, the majority of RA and UA patients who had been treated to target low DAS or DAS remission were in DAS remission and had limited functional disability. Radiographic damage progression was mild although not completely suppressed.

Altered serum metabolome as an indicator of paraneoplasia or concomitant cancer in patients with rheumatic disease.

OBJECTIVES: A timely diagnosis is imperative for curing cancer. However, in patients with rheumatic musculoskeletal diseases (RMDs) or paraneoplastic syndromes, misleading symptoms frequently delay cancer diagnosis. As metabolic remodelling characterises both cancer and RMD, we analysed if a metabolic signature can indicate paraneoplasia (PN) or reveal concomitant cancer in patients with RMD. METHODS: Metabolic alterations in the sera of rheumatoid arthritis (RA) patients with (n=56) or without (n=52) a history of invasive cancer were quantified by nuclear magnetic resonance analysis. Metabolites indicative of cancer were determined by multivariable regression analyses. Two independent RA and spondyloarthritis (SpA) cohorts with or without a history of invasive cancer were used for blinded validation. Samples from patients with active cancer or cancer treatment, pulmonary and lymphoid type cancers, paraneoplastic syndromes, non-invasive (NI) precancerous lesions and non-melanoma skin cancer and systemic lupus erythematosus and samples prior to the development of malignancy were used to test the model performance. RESULTS: Based on the concentrations of acetate, creatine, glycine, formate and the lipid ratio L1/L6, a diagnostic model yielded a high sensitivity and specificity for cancer diagnosis with AUC=0.995 in the model cohort, AUC=0.940 in the blinded RA validation cohort and AUC=0.928 in the mixed RA/SpA cohort. It was equally capable of identifying cancer in patients with PN. The model was insensitive to common demographic or clinical confounders or the presence of NI malignancy like non-melanoma skin cancer. CONCLUSIONS: This new set of metabolic markers reliably predicts the presence of cancer in arthritis or PN patients with high sensitivity and specificity and has the potential to facilitate a rapid and correct diagnosis of malignancy.

Polymorphic lymphoproliferative disorder arising in a rheumatoid arthritis patient, presenting as fibrin-associated large B-cell lymphoma-like lesions in aortic and mitral valves.

We herein report a case of methotrexate-associated lymphoproliferative disorder (MTX-LPD) showing fibrin-associated large B-cell lymphoma-like heart valve lesions, and Epstein-Barr virus (EBV)-positive mucocutaneous ulcer-like cutaneous and oral mucosal lesions. MTX-LPD is a critical complication that can occur in RA patients who are treated with MTX. EBV also plays a defining or important role in LPDs. Among the sites of MTX-LPD, 40-50% occur in extranodal sites, including the gastrointestinal tract, skin, liver, lung, and kidney. There are few reports of MTX-LPDs involving the heart valves, and to the best of our knowledge, this is the first case to be reported in the English literature. The possibility of EBV-positive LPD should be considered in RA patients, even in patients with an atypical site, as in this case.

Sociodemographic and clinical variables associated with negative illness perception in patients newly diagnosed with rheumatoid arthritis, axial spondyloarthritis, or psoriatic arthritis-a survey based cross-sectional study.

When newly diagnosed with inflammatory arthritis (IA), acquiring self-management skills is beneficial, to enhance quality of life. The personal beliefs and mental representations patients hold about their illness, known as illness perception, significantly influence the development of these skills. Recognizing characteristics that affect illness perception is key to identifying patients requiring additional support for the development of self-management skills. This study aimed at identifying the sociodemographic and clinical characteristics associated with a negative illness perception. This cross-sectional study was based on survey data from patients diagnosed for ≤ 2 years. The Brief Illness Perception Questionnaire (B-IPQ) was used to measure illness perception. After psychometric testing, we divided the B-IPQ into two domains: (1) a control domain and (2) a consequence domain. We performed logistic regression analyses with multiple imputations. A total of 1,360 patients (61% females) were included. Among them, 64%, 20%, and 16% were diagnosed with rheumatoid arthritis, psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA), respectively. Younger patients with lower socioeconomic status, a diagnosis of PsA or axSpA, high disease activity (OR 3.026, CI 2.208;4.147), severe physical disability (OR 4.147. CI 2.883;6.007), severe pain (OR 3.034, CI 1.991;4.622), and severe fatigue (OR 2.612, CI 1.942;3.513) were significantly more likely to report having a negative illness perception. Younger patients with a higher symptom burden, increased disease activity, lower socioeconomic status, and a diagnosis of PsA or axSpA may require additional attention and support in rheumatology clinical practice to aid in the development of their self-management skills.

A novel neuroimmune modulation system for the treatment of rheumatoid arthritis.

The vagus nerve has an anti-inflammatory effect through the inflammatory reflex, which inhibits the release of proinflammatory cytokines by macrophages. Recent pilot clinical trials, using implantable bioelectronic devices, have demonstrated the efficacy of vagus nerve stimulation in adult patients with rheumatoid arthritis and inflammatory bowel diseases as an alternative to drugs, which are not devoid of side effects and are costly. In this issue of Bioelectronic Medicine, Peterson et al. report the safety of novel implantable neuroimmune modulation device for treating rheumatoid arthritis (The RESET RA study), which I will discuss in this commentary.

Identification and validation of mutual hub genes in idiopathic pulmonary fibrosis and rheumatoid arthritis-associated usual interstitial pneumonia.

Objectives: The study aims at exploring common hub genes and pathways in idiopathic pulmonary fibrosis (IPF) and rheumatoid arthritis-associated usual interstitial pneumonia (RA-UIP) through integrated bioinformatics analyses. Methods: The GSE199152 dataset containing lung tissue samples from IPF and RA-UIP patients was acquired from the Gene Expression Omnibus (GEO) database. The identification of overlapping differentially expressed genes (DEGs) in IPF and RA-UIP was carried out through R language. Protein-protein interaction (PPI) network analysis and module analysis were applied to filter mutual hub genes in the two diseases. Enrichment analyses were also conducted to analyze the possible biological functions and pathways of the overlapped DEGs and hub genes. The diagnostic value of key genes was assessed with R language, and the expressions of these genes in pulmonary cells of IPF and rheumatoid arthritis-associated interstitial lung disease (RA-ILD) patients were analyzed with single cell RNA-sequencing (scRNA-seq) datasets. The expression levels of hub genes were validated in blood samples from patients, specimens of human lung fibroblasts, lung tissue samples from mice, as well as external GEO datasets. Results: Four common hub genes (THBS2, TIMP1, POSTN, and CD19) were screened. Enrichment analyses showed that the abnormal expressions of DEGs and hub genes may be connected with the onset of IPF and RA-UIP by regulating the progression of fibrosis. ScRNA-seq analyses illustrated that for both IPF and RA-ILD patients, THBS2, TIMP1, and POSTN were mainly expressed in lung fibroblasts, while CD19 was uniquely high-expressed in B cells. The qRT-PCR and immunohistochemistry (IHC) results verified that the expression levels of hub genes were mostly in accordance with the findings obtained from the bioinformatics analyses. Conclusion: Though IPF and RA-UIP are distinct diseases, they may to some extent have mutual pathogenesis in the development of fibrosis. THBS2, TIMP1, POSTN, and CD19 may be the potential biomarkers of IPF and RA-UIP, and intervention on related pathways of these genes could offer new strategies for the precision treatment of IPF and RA-UIP.

Identification and validation of immune-related genes in osteoarthritic synovial fibroblasts.

Objective: OA was generally considered as a non-inflammatory disease dominated by articular cartilage degeneration. However, the role of synovitis in OA pathogenesis has received increasing attention. Recent studies support that OA patients have a pro-inflammatory/catabolic synovial environment similar to RA patients, promoting the occurrence and development of OA. Therefore, we investigated the co-immune-related genes and pathways of OA and RA to explore whether part of the pathogenesis of RA synovitis can be used to explain OA synovitis. Methods: Data of GSE29746 and GSE12021 were downloaded from the Gene Expression Omnibus (GEO) database. Compared with control group, differentially expressed genes (DEGs) of OA and RA groups were screened separately by R software, Venny website was used to screen co-DEGs. Metascape was used to screen the common enriched terms and pathways between OA and RA. STRING website and Cytoscape software were used to map protein-protein interaction (PPI) networks and screen co-hub genes. GSE29746 was selected as the test dataset, and GSE12021 as the validation dataset for validate the co-hub genes. The results were validated by western blotting (WB) and real-time quantitative polymerase chain reaction (qPCR) of clinical synovial samples. Results: We identified 573 OA-related DEGs, 148 RA-related DEGs, and 52 co-DEGs, revealing 14 common enriched terms, most of which were related to immune inflammation. IL7R was the only upregulated co-hub gene between OA and RA in the PPI network, consistent with the validation dataset. IL7R was highly expressed in clinical osteoarthritic synovial samples (P < 0.001). Conclusion: Our findings suggested that IL7R is a critical co-DEG in OA and RA and confirmed the involvement of immune inflammation in disease pathogenesis. Furthermore, it confirms the role of IL7R in synovial inflammation in RA and OA synovitis and provides evidence for further investigation of OA immune inflammation.