Adipose-derived mesenchymal stem cell therapy for connective tissue diseases and complications.

Mesenchymal stem cells (MSCs) may be effective in treating connective tissue disease and associated organ damage, leveraging their anti-inflammatory and immunoregulatory effects. Moreover, MSCs may possess the ability to produce antiapoptotic, proliferative, growth, angiogenic, and antifibrotic factors. Among MSCs, adipose-derived MSCs (ASCs) stand out for their relative ease of harvesting and abundance. Additionally, studies have indicated that compared with bone marrow-derived MSCs, ASCs have superior immunomodulatory, proangiogenic, antiapoptotic, and antioxidative properties. However, relatively few reviews have focused on the efficacy of ASC therapy in treating connective tissue disease (CTD) and interstitial lung disease (ILD). Therefore, this review aims to evaluate evidence from preclinical studies that investigate the effectiveness of MSC therapy, specifically ASC therapy, in managing CTD and ILD. Moreover, we explore the outcomes of documented clinical trials. We also introduce an innovative approach involving the utilization of pharmacologically primed ASCs in the CTD model to address the current challenges associated with ASC therapy.

Deciphering the Reactivity of Autoantibodies Directed against the RNP-A, -C and 70 kDa Components of the U1-snRNP Complex: "Double or Nothing"?

Background: The positivity of anti-RNP autoantibodies as biological criteria for the diagnosis of mixed connective tissue disease (MCTD) has recently divided the rheumatology community. Autoantigenicity of the U1-snRNP complex tends to generate multiple autoantibodies against RNP-A, -C and -70 KDa or Sm proteins. The aim of this study is to identify the most informative autoantibodies in clinical practice, in particular, to contribute to differential diagnosis between MCTD and systemic lupus erythematosus (SLE). Methods: Sera from 74 patients positive for anti-RNP autoantibodies were selected over a period of one year of laboratory practice. Autoantibodies directed against extractable nuclear antigen, RNP proteins (A, C, 70 KDa) and 40 kDa fragments of RNP-70 KDa were investigated by using quantitative fluoroenzymatic assay and Western blot analysis. Results: Among the 74 patients, 40 patients were diagnosed with SLE, 20 with MCTD, six with another autoimmune disease, three with SARS-CoV-2 infection, three with cancer and two were healthy. No preferential clinical association of IgG or IgM autoantibodies directed against each of the RNP proteins was found between SLE and MCTD. In contrast, the proportion of autoantibodies directed against the RNP component within the U1-snRNP complex showed a significantly higher RNP index in patients with MCTD than in those with SLE (p = 0.011), with good performance (sensitivity: 69.2%, specificity: 88.9%). Conclusions: The analysis of the proportion of the different autoantibodies directed against the U1-snRNP complex is more informative than the analysis of each autoantibody separately. A follow-up of patients could be informative about the interest of the RNP index as a predictor of disease evolution.

Sleep Disorders in Connective Tissue Diseases-Coexisting Diseases or Disease Components?

This comprehensive review examines the complex relationship between sleep disorders and rheumatic diseases, supported by findings from the latest research articles. It encompasses various rheumatic conditions, including rheumatoid arthritis, systemic lupus erythematosus, and systemic sclerosis. The review reveals the bidirectional relationship between sleep disorders and these diseases, emphasizing their impact on disease progression and quality of life. Conventional and alternative therapeutic interventions for connective tissue diseases are presented, focusing on improving sleep quality and alleviating rheumatic symptoms. The role of pro-inflammatory cytokines and their potential modulation through pharmacological agents is also discussed. In the treatment of sleep disorders, various options are proposed, such as cognitive behavioral therapy for insomnia, physical activity, dietary modifications, and alternative approaches like reflexology and acupuncture. Thus, this review offers a nuanced understanding of the connection between sleep disorders and rheumatic diseases, supported by evidence from diverse studies. Such an approach is particularly important because it enhances sleep quality for overall patient well-being in the holistic management of rheumatic conditions.

A Challenging Case: Unraveling the Complexities of Undifferentiated Connective Tissue Disease.

Undifferentiated connective tissue disease (UCTD) poses a significant diagnostic challenge due to its wide array of clinical presentations and the absence of specific diagnostic criteria. We present the case of a 22-year-old female who initially exhibited symptoms resembling the common flu, including recurrent fever, headaches, and constitutional symptoms. Despite initial tests showing no abnormalities and negative autoimmune serology, her symptoms persisted, prompting further investigation. Although subsequent imaging studies yielded no definitive diagnosis, her elevated inflammatory markers and progressively positive antinuclear antibody (ANA) test after the initial negative result suggested an underlying autoimmune process. After six months of persistent symptoms, treatment with hydroxychloroquine initiated by a rheumatologist led to a remarkable resolution of her symptoms. This case highlights the challenge of diagnosing UCTD, particularly in young individuals, where symptoms may manifest early in life without clear laboratory abnormalities, sometimes with initial negative ANA, making it a learning point to recheck ANA levels even if they were initially negative. It underscores the importance of considering UCTD in patients with unexplained symptoms and inconclusive laboratory findings, as early initiation of appropriate treatment can significantly alleviate symptoms and improve patient outcomes.

Excessive Dynamic Airway Collapse After Entecavir Use in a Patient With Pegylated Interferon-Induced Undifferentiated Connective Tissue Disease and Entecavir Use to Prevent Hepatitis B Virus Reactivation Upon Giving Rituximab.

Pegylated interferon-alpha (PEG-IFN-α) is an antiviral medication used to treat chronic hepatitis C virus (HCV) and hepatitis B virus (HBV) infections. It may result in rare but severe side effects, such as undifferentiated connective tissue disease (UCTD) and excessive dynamic airway collapse (EDAC), which can occur as delayed complications of PEG-IFN-α-induced UCTD. In cases where these complications arise, entecavir, employed for treating HBV infection, may be considered. A 49-year-old female patient, monitored for nine years with HCV and a viral load of 1.5 million, genotype 3, and normal liver function tests (LFTs), possibly acquired the infection from her HCV-positive husband. The patient was initially treated with PEG-IFN-α (IFN-α-2b, 100 µg/week subcutaneously) and ribavirin (RBV, 500 mg/twice daily). Following the sixth injection, the patient exhibited symptoms, including shortness of breath and cough, leading to limited daily activities. Subsequent high-resolution computed tomography (HRCT) showed interstitial pneumonitis (IP) signs. She was given a high dose of steroids. Over the next two to four weeks, the patient experienced Raynaud's phenomenon, skin tightening, joint pains, and dryness of the eyes and mouth. The antinuclear antibody (ANA) test was negative, while the extractable nuclear antigen (ENA) test showed equivocal anti-Smith antibodies (6.38). Rheumatoid factor (RA) factors were mildly positive, and pulmonary function tests (PFTs) indicated a restrictive pattern. The patient was intolerant to hydroxychloroquine (HCQ) and azathioprine (Imuran) 500 mg, subsequently receiving mycophenolate mofetil 500 mg/thrice daily. Despite four years of treatment, UCTD due to PEG-IFN-α remained difficult to control; however, IP responded well to steroids. Rituximab pulse therapy was planned before the initiation; serological tests showed positive anti-HBs with a titer of 17.02, positive anti-HBc, but negative HBsAg and undetectable HBV viral load, indicating immunity to HBV due to natural infection. Given the potential for rituximab to cause immunosuppression and HBV reactivation, entecavir treatment was started and continued for 18 months. The patient was followed for another five years, during which her LFTs and viral markers showed stability. However, after nine years of PEG-IFN-α-induced UCTD disorder, she experienced a reoccurring cough but was unresponsive to steroids that were against her suspicion of a flare of IP. A subsequent dynamic CT scan detected a 75% trachea collapse while in a supine position, indicating a potential complication termed EDAC. This EDAC could not be linked to PEG-IFN-α-induced UCTD disorder or EDAC after the use of entecavir in a patient with PEG-IFN-α-induced UCTD disorder. Treatment of such complex patients requires flexible, specific treatment plans and continuous monitoring. This case emphasizes the need for caution in patients with a history of IFN-induced disease and the possibility of late effects and possible effects of the use of entecavir in a patient with PEG-IFN-α-induced UCTD. To the best of our knowledge, this is the first case reported as EDAC, a possible delayed complication of PEG-IFN-α plus ribavirin or entecavir in a patient with PEG-IFN-α-induced UCTD.

Pilot study exploring artificial intelligence for facial-image-based diagnosis of Marfan syndrome.

Background: Marfan Syndrome (MFS), a genetic disorder impacting connective tissue, manifests in a wide array of phenotypes which can affect numerous bodily systems, especially the thoracic aorta. The syndrome often presents distinct facial features that potentially allow for diagnostic clinical recognition. Herein, we explore the potential of Artificial Intelligence (AI) in diagnosing Marfan syndrome from ordinary facial images, as assessed by overall accuracy, F1 score, and area under the ROC curve. Methods: This study explores the utilization of Convolutional Neural Networks (CNN) for MFS identification through facial images, offering a novel, non-invasive, automated, and computerized diagnostic approach. The research examines the accuracy of Neural Networks in the diagnosis of Marfan Disease from ordinary on-line facial images. The model was trained on 80 % of 672 facial images (182 Marfan and 490 control). The other 20 % of images were used as the test set. Results: Overall accuracy was 98.5 % (0 % false positive, 2 % false negative). F1 score was 97 % for Marfan facies and 99 % for non-Marfan facies. Area under the ROC curve was 100 %. Conclusion: An Artificial Intelligence (AI) program was able to distinguish Marfan from non-Marfan facial images (from ordinary on-line photographs) with an extremely high degree of accuracy. Clinical usefulness of this program is anticipated. However, due to the limited and preliminary nature of this work, this should be viewed as only a pilot study.

Camptodactyly-arthropathy-coxa vara-pericarditis (CACP) syndrome.

Camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP) is a rare autosomal recessive disease caused by mutation in proteoglycan 4 (PRG4) gene on chromosome 1q25-q31. We faced a dilemma and delay in diagnosis in two sisters. The elder sister had pericardial effusion with constrictive pericarditis, underwent pericardiectomy and received empirical treatment for suspected tuberculosis. After 2 years, she developed bilateral knee swelling with restriction of movement. At the same time, her younger sister also presented with bilateral knee swelling which aroused the suspicion of genetic disease. The whole-genome sequencing revealed homozygous PRG4 mutation suggestive of CACP syndrome.

Impressive resolution of refractory hypertrophic discoid lupus erythematosus with anifrolumab.

Hypertrophic discoid lupus erythematosus is a rare variant of chronic cutaneous lupus erythematosus and is often challenging to treat. A male in his early 60s presented with diffuse erythematous, crusty, pruritic plaques on his upper and lower extremities, face, upper back, dorsal aspect of the hands and chest. He also described prolonged morning stiffness, swelling of his fingers and wrists, oral sores and Raynaud's phenomenon. He was positive for antinuclear antibody and anti-SSA antibody and had low C3 and C4 proteins. The skin biopsy was consistent with hypertrophic discoid lupus erythematosus. He was diagnosed with systemic lupus erythematosus. Skin lesions were refractory to treatment with topical corticosteroids, topical acitretin, hydroxychloroquine, azathioprine or mycophenolate. Anifrolumab infusions were initiated with a near-complete resolution of cutaneous symptoms within 3 months.

A Case of Overlapping Autoimmune Syndrome.

Overlapping autoimmune disorders are used to describe the coexistence of more than one autoimmune disease in the same patient. Mixed connective tissue disease (MCTD) and anti-synthetase syndrome (ASS) are autoimmune diseases that manifest with pulmonary involvement, presenting as persistent dyspnea. The coexistence of both conditions in the same patient is extremely rare. We herein report a case of a 44-year-old female who was diagnosed with MCTD with features of ASS (anti-Jo-1 antibody) in the setting of rheumatoid arthritis (anti-cyclic citrullinated peptide (anti-CCP) antibody), which shows temporary breathing improvement following treatment with corticosteroid and mycophenolate mofetil. However, after the completion of mycophenolate mofetil, she was found to be anti-Jo-1 antibody negative and anti-CCP antibody positive. Our case emphasizes the need to recognize overlapping autoimmune conditions in patients with complex clinical features and presentations with the immediate application of a comprehensive diagnostic approach and tailored treatment strategies. Early diagnosis and aggressive treatment are crucial for achieving remission and preventing organ damage.

Serum S1P level in interstitial lung disease (ILD) is a potential biomarker reflecting the severity of pulmonary function.

BACKGROUND: sphingosine-1-phosphate (S1P), a naturally occurring sphingolipid, has been involved in pulmonary interstitial remodeling signaling. However, no study has examined its clinical merits for interstitial lung disease (ILD). This study aimed to investigate the serum level of S1P in ILD patients and its clinical correlation with the severity of disease in the two main types of ILDs: the IPF and the CTD-ILD patients. METHODS: This retrospective observational pilot study included 67 ILD patients and 26 healthy controls. These patients were stratified into the IPF group (35) and the CTD-ILD group (32). The severity of ILD was evaluated through pulmonary function indicators and the length of hospital stay. RESULTS: Serum S1P level was statistically higher in ILD patients than in health control (p = 0.002), while the Serum S1P levels in CTD-ILD and IPF patients were comparable. Serum S1P level further showed statistically negative correlation with pulmonary function indexes (TLC% pred, FVC% pred and FEV1% pred) and positive correlation with length of hospital stay (r = -0.38, p = 0.04; r = -0.41, p = 0.02, r = -0.37, p = 0.04; r = 0.42, p = 0.02, respectively) in CTD-ILD patients, although serum S1P level was not significantly correlated with inflammatory indexes. The IPF patients failed to exhibit a significant correlation of serum S1P level with pulmonary function and length of hospital stay. CONCLUSIONS: Serum S1P level might be a clinically useful biomarker in evaluating the severity of CTD-ILD patients rather than IPF patients.

Nintedanib combined with immunosuppressive agents improves forced vital capacity in connective tissue disease-associated PF-ILD: a single-center study.

BACKGROUND: In 2020, Nintedanib (NTB), a tyrosine kinase inhibitor, was the first drug approved worldwide for treating progressive fibrosing interstitial lung disease (PF-ILD). This study evaluated the efficacy and safety of NTB in Japanese patients with CTD-associated PF-ILD in a real-world setting, as there are few reports on this topic. We also evaluated the efficacy and safety of combination therapy with NTB and immunosuppressive agents (IS). METHODS: CTD-associated PF-ILD patients receiving NTB at our institution were included in this retrospective study. To evaluate the efficacy and safety of NTB, we investigated changes in forced vital capacity (FVC) (%), diffusing capacity for carbon monoxide (DLCO) (%), monthly change in FVC (%/month), serum Krebs von den Lungen-6 (KL-6) levels (U/mL) before and after NTB treatment, and adverse events (AEs) during NTB treatment. Moreover, to evaluate the efficacy of the NTB + IS combination therapy, we divided the patients into two groups: one received only NTB (NTB group), and the other received both NTB and IS (NTB + IS group) following the diagnosis of CTD-associated PF-ILD. We analyzed the differences in the changes of these variables between the two groups. RESULTS: Twenty-six patients with CTD-associated PF-ILD were included. After NTB treatment, there were no significant deteriorations in FVC (%) and DLCO (%), while the monthly change in FVC (%/month) significantly increased (p < 0.001). The changes in FVC (%) and the monthly change in FVC (%/month) were significantly greater in the NTB + IS group than in the NTB group. Following NTB treatment, the mean serum KL-6 levels significantly decreased (p < 0.001). AEs associated with NTB in this study were similar to those in previous clinical trials, and there was no significant difference in the incidence of AEs between the two groups. CONCLUSIONS: This study demonstrates that NTB is an effective medication for slowing the progression of CTD-associated PF-ILD in real-world settings. NTB + IS combination therapy for CTD-associated PF-ILD may be more effective than NTB alone in slowing the progression of CTD-associated PF-ILD.

Drug-Induced Undifferentiated Connective Tissue Disease in a Two-Year-Old Girl: A Manifestation of Factitious Disorder Imposed on Another (FDIA).

Factitious disorder imposed on another (FDIA), formerly known as Munchausen syndrome by proxy (MSBP), constitutes a form of child abuse wherein a caregiver fabricates or induces illness in a person under their care or supervision. Here, we present a case of a two-year-old girl with signs and symptoms suggestive of undifferentiated connective tissue disease (UCTD) and probable autoinflammatory disease, which was a manifestation of FDIA. The patient manifested recurrent febrile episodes and presented with hepatosplenomegaly, elevated inflammatory markers, and mesangial proliferative glomerulonephritis. Regardless of extensive medical interventions, including corticosteroids and immunosuppressive therapy, the patient's condition failed to improve until the caregiver was isolated from the patient. Upon questioning, the caregiver admitted to having administered pyrogenal, an immunomodulator, to induce symptoms. This case highlights the challenges and difficulties of diagnosing and managing FDIA-associated illnesses, drawing attention to the importance of considering this diagnosis in cases of unexplained or recurrent fever in children.

An explainable machine learning-based model to predict intensive care unit admission among patients with community-acquired pneumonia and connective tissue disease.

BACKGROUND: There is no individualized prediction model for intensive care unit (ICU) admission on patients with community-acquired pneumonia (CAP) and connective tissue disease (CTD) so far. In this study, we aimed to establish a machine learning-based model for predicting the need for ICU admission among those patients. METHODS: This was a retrospective study on patients admitted into a University Hospital in China between November 2008 and November 2021. Patients were included if they were diagnosed with CAP and CTD during admission and hospitalization. Data related to demographics, CTD types, comorbidities, vital signs and laboratory results during the first 24 h of hospitalization were collected. The baseline variables were screened to identify potential predictors via three methods, including univariate analysis, least absolute shrinkage and selection operator (Lasso) regression and Boruta algorithm. Nine supervised machine learning algorithms were used to build prediction models. We evaluated the performances of differentiation, calibration, and clinical utility of all models to determine the optimal model. The Shapley Additive Explanations (SHAP) and Local Interpretable Model-Agnostic Explanations (LIME) techniques were performed to interpret the optimal model. RESULTS: The included patients were randomly divided into the training set (1070 patients) and the testing set (459 patients) at a ratio of 70:30. The intersection results of three feature selection approaches yielded 16 predictors. The eXtreme gradient boosting (XGBoost) model achieved the highest area under the receiver operating characteristic curve (AUC) (0.941) and accuracy (0.913) among various models. The calibration curve and decision curve analysis (DCA) both suggested that the XGBoost model outperformed other models. The SHAP summary plots illustrated the top 6 features with the greatest importance, including higher N-terminal pro-B-type natriuretic peptide (NT-proBNP) and C-reactive protein (CRP), lower level of CD4 + T cell, lymphocyte and serum sodium, and positive serum (1,3)-ß-D-glucan test (G test). CONCLUSION: We successfully developed, evaluated and explained a machine learning-based model for predicting ICU admission in patients with CAP and CTD. The XGBoost model could be clinical referenced after external validation and improvement.

Diagnostic yield of flexible bronchoscopy for immunocompromised patients with lung infiltrates: A single-center, retrospective study.

BACKGROUND: Pulmonary complications are associated with mortality in immunocompromised patients. The usefulness of bronchoscopy has been reported. However, clinical factors and procedures that influence diagnostic yield are still not established. MATERIALS AND METHODS: We retrospectively analyzed 115 bronchoscopies performed on 108 immunocompromised patients, defined as those who take corticosteroids and/or immunosuppressants. We evaluated clinical factors, sampling procedures, final diagnosis, and severe complications of bronchoscopy. RESULTS: The clinical diagnosis was obtained in 51 patients (44%). Of those, 33 cases were diagnosed as infectious diseases and 18 as non-infectious diseases. Nine out of 115 cases (7.8%) initiated new immunosuppressive treatment for an underlying disorder based on the negative microbiological results obtained with bronchoscopy. Collagen vascular disease was the most common underlying disorders (62 patients, 54%). Bronchoscopy was useful regardless of whether the patient was immunosuppressed to treat collagen vascular disease (P = 0.47). Performing transbronchial biopsy correlated with better diagnostic yield of bronchoscopy (54.7% vs 35.5%, P = 0.049). Other clinical factors, such as radiological findings, respiratory failure or antibiotic use at the time of bronchoscopy did not significantly influence diagnostic yield. Respiratory failure requiring intubation after bronchoscopy occurred only in one case (0.9%). CONCLUSIONS: Our study implied the transbronchial biopsy may be a useful procedure for reaching a diagnosis in immunocompromised patients with pulmonary infiltrates. In addition, our data suggest the usefulness of bronchoscopy for immunocompromised patients due to the treatment of collagen vascular disease as well as other underlying disorders.