IgG₄ is a subclass of IgG. Elevated serum IgG₄ levels are an important serological feature of IgG₄ related diseases and serve as a serological marker for assessing disease activity and severity. The harmonization of IgG₄ detection is crucial for its clinical application. National Clinical Research Center for Dermatologic and Immunologic Diseases (Peking Union Medical College Hospital), Experimental Diagnosis Research Committee, Rheumatology and Immunology Physicians Committee of Chinese Medical Doctor Association, Autoantibodies Detection Committee, and Chinese Rheumatism Data Center have organized clinical and laboratory experts to draft this consensus, aiming to standardize IgG₄ detection and provide guideline for clinician and laboratory experts to appropriate utility and interpret IgG₄ results in China.
Humans ; China ; Consensus ; Immunoglobulin G/blood*

Objective To identify the possibility of IgG Fc binding protein (FCGBP) acting as a prognostic marker of low-grade glioma (LGG) and its correlation with immune infiltration. Methods The expression of FCGBP was analyzed in pan-cancer using The Cancer Genome Atlas (TCGA), Genotypic tissue expression (GTEX), and China Glioma Genome Atlas (CGGA) database. Then, GSE15824 and GSE68848 datasets were selected for further verification. And gene expression Profile Interaction analysis (GEPIA) database and R language were used to analyze the relationship between FCGBP and survival prognosis. Metascape and GSEA were used for functional annotation and enrichment analysis. Finally, the expression of FCGBP gene in LGG immune microenvironment and its correlation with immune cells were analyzed by TIMER database. Results FCGBP was highly expressed in LGG tissues, indicating poor prognosis of LGG patients. Receiver operating characteristic (ROC) curve analysis and COX analysis showed that FCGBP was an independent risk factor for the prognosis of LGG. Moreover, Gene Ontology (GO) demonstrated that FCGBP was involved in cell metabolism, localization, positive, and negative regulation of biological processes, as well as biological adhesion, response to viral and microbial stimulation, and inflammation. GSEA pathway enrichment analysis showed that FCGBP was significantly correlated with Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway, Toll-like receptor (TLR) pathway, chemokine pathway, and P53 pathway. In addition, FCGBP expression was positively correlated with the expression of most immune cells in the immune microenvironment of LGG. Conclusion The high expression of FCGBP in LGG is a risk factor for survival and prognosis, and it is positively correlated with the expression of immune cells.
Humans ; Prognosis ; Glioma/genetics* ; China ; Gene Ontology ; Immunoglobulin G ; Tumor Microenvironment ; Cell Adhesion Molecules

Kawasaki disease (KD) is an acute self-limiting vasculitis, and it is the most common cause of acquired heart disease in children under 5 years old. One of the improvement goals in pediatric quality control work for the year 2023, as announced by the National Health Commission, is to reduce the incidence of cardiac events and KD-related mortality in children with KD. In order to standardize the diagnosis, treatment, and long-term management practices of KD in China, and effectively prevent and reduce the incidence of coronary artery lesions and long-term adverse effects, the guideline working group followed the principles and methods outlined by the World Health Organization and referenced existing evidence and experiences to develop the "Evidence-based guidelines for the diagnosis and treatment of Kawasaki disease in children in China (2023)". The guidelines address the clinical questions regarding the classification and definition of KD, diagnosis of different types of KD, treatment during the acute phase of KD, application of echocardiography in identifying complications of KD, and management of KD combined with macrophage activation syndrome. Based on the best evidence and expert consensus, 20 recommendations were formulated, aiming to provide guidance and decision-making basis for healthcare professionals in the diagnosis and treatment of KD in children.
Child ; Humans ; Child, Preschool ; Mucocutaneous Lymph Node Syndrome/complications* ; Vasculitis/drug therapy* ; Heart ; Heart Diseases ; China ; Immunoglobulins, Intravenous/therapeutic use*

OBJECTIVES: Based on peripheral blood lymphocyte subsets and common laboratory test indexes, this study aimed to construct a predictive scoring system for intravenous immunoglobulin (IVIG)-resistant Kawasaki disease (KD). METHODS: Children hospitalized in Tianjin Children's Hospital from January 2021 to March 2023 were included in the study (185 cases of IVIG-sensitive KD and 41 cases of IVIG -resistant KD). Forty-six healthy children matched for age and gender were selected as controls. The relative percentage and absolute counts of peripheral lymphocyte subsets were measured by flow cytometry. Multivariate logistic regression was used to identify the predictive factors for IVIG-resistant KD and to construct a predictive scoring system for predicting IVIG-resistant KD. RESULTS: The multivariate logistic regression analysis showed that CD4⁺ T cell absolute count, natural killer cell absolute count, serum sodium level, globulin level, and total bilirubin level were identified as predictive factors for IVIG-resistant KD (P<0.05). The predictive scoring system based on these factors achieved a sensitivity of 70.7% and a specificity of 83.8% in predicting IVIG-resistant KD. CONCLUSIONS Peripheral blood lymphocyte subsets can serve as predictive indicators for IVIG-resistant KD in children. The introduction of this indicator and the establishment of a scoring system based on it can provide a higher accuracy in predicting IVIG-resistant KD in children.
Child ; Humans ; Infant ; Immunoglobulins, Intravenous/therapeutic use* ; Mucocutaneous Lymph Node Syndrome/drug therapy* ; Lymphocyte Count ; Lymphocyte Subsets ; Retrospective Studies

OBJECTIVE: To analyze the clinical characteristics of venous thromboembolism (VTE) in patients with multiple myeloma (MM) and to identify the risk factors of VTE in MM patients. METHODS: 179 newly diagnosed MM (NDMM) patients admitted to The Second Hospital of Shanxi Medical University from January 2014 to December 2020 who were followed up for more than 6 months were collected, and they were divided into VTE group and control group according to whether combined with VTE. The clinical and laboratory data were compared between the two groups. Mann-whitney U test was used for inter-group comparison of measurement data, Chi-square test or Fisher's exact test was used for inter-group comparison of count data, and multivariate logistic regression analysis was performed to explore the risk factors of VTE in MM patients. RESULTS: Compared with control group, the serum albumin (ALB) level in VTE group was significantly lower (P =0.033), the fibrinogen (FIB) level was significantly higher (P =0.016), and the proportion of patients with D-dimer≥2 000 ng/ml was significantly higher than that in the control group (26.3% vs 4.4%, P =0.002). There was a significant difference in M-component type between the two groups (P =0.028), and the proportion of IgG type in VTE group was higher. There were no statistically significant differences between two groups in age, sex, body mass index (BMI), the proportions of patients with hypertension, diabetes, coronary heart disease and cerebral infarction, white blood cell (WBC) count, platelet (PLT) count, liver and kidney function, plasma cells ratio in bone marrow, serum globulin (GLO), lactate dehydrogenase (LDH), β₂-microglobulin (β₂-MG) level, C-reactive protein (CRP) level, erythrocyte sedimentation rate (ESR), prothrombin time (PT), activated partial thromboplastin time (APTT), disease stage, thrombosis prevention and the use of immunomodulators (P >0.05). Multivariate logistic regression analysis showed that FIB level (OR=1.578, 95%CI:1.035-2.407, P =0.034), D-dimer≥2 000 ng/ml (OR=5.467, 95%CI:1.265-23.621, P =0.023) and IgG type (OR=4.780, 95%CI: 1.221-18.712, P =0.025) were independent risk factors for VTE in MM patients. CONCLUSION MM patients are prone to VTE, and FIB level, D-dimer≥2 000 ng/ ml and IgG type are independent risk factors for VTE in MM patients.
Humans ; Venous Thromboembolism ; Multiple Myeloma/complications* ; Risk Factors ; Anticoagulants ; Immunoglobulin G ; Retrospective Studies

OBJECTIVE: To investigate the role of multiple serological methods in the identification of complex antibodies. METHODS: The blood group antigens were detected by saline and microcolumn agglutination methods. The saline method was used to screen and identify IgM-type antibodies in the patient's serum, while the polybrene, anti-globulin, microcolumn agglutination, enzymic and absorption-elution methods were used to screen and identify IgG-type antibodies. RESULTS: The patient was B/CCDee/Jk(a-b+)/Fy(a-b+) blood type. The serum reacted with panel cells, and the reaction presented anti-E pattern in the saline medium. It was fully positive in the microcolumn agglutination card, except 2 negative ones after using papain to treat the panel cells. Referring to the pattern table, it was concluded that there existed anti-c, anti-E, and anti-Jk^a antibodies, and one antibody corresponding to an antigen that was easily destroyed by papain. The red blood cells with specific phenotype were selected for absorption-elution to identify IgG-type anti-c, anti-E, anti-Jk^a and anti-Fy^a antibodies. CONCLUSION It is confirmed that IgM-type anti-E, and IgG-type anti-c, anti-E, anti-Jk^a and anti-Fy^a antibodies exist in the patient's serum by multiple serological methods.
Humans ; Papain ; Blood Group Antigens ; Erythrocytes ; Immunoglobulin G ; Immunoglobulin M

Humans ; Child ; Immunoglobulin G ; Autoimmune Diseases ; Hepatitis, Autoimmune ; Pancreatic Diseases ; Pancreatic Neoplasms

Objective: To analyze the clinical characteristics of children with multisystem inflammatory syndrome (MIS-C) associated with SARS-CoV-2 in China, and to improve the understanding of MIS-C among pediatricians. Methods: Case series study.Collect the clinical characteristics, auxiliary examinations, treatment decisions, and prognosis of 64 patients with MIS-C from 9 hospitals in China from December 2022 to June 2023. Results: Among the 64 MIS-C patients, 36 were boys and 28 were girls, with an onset age being 2.8 (0.3, 14.0) years. All patients suffered from fever, elevated inflammatory indicators, and multiple system involvement. Forty-three patients (67%) were involved in more than 3 systems simultaneously, including skin mucosa 60 cases (94%), blood system 52 cases (89%), circulatory system 54 cases (84%), digestive system 48 cases (75%), and nervous system 24 cases (37%). Common mucocutaneous lesions included rash 54 cases (84%) and conjunctival congestion and (or) lip flushing 45 cases (70%). Hematological abnormalities consisted of coagulation dysfunction 48 cases (75%), thrombocytopenia 9 cases (14%), and lymphopenia 8 cases (13%). Cardiovascular lesions mainly affected cardiac function, of which 11 patients (17%) were accompanied by hypotension or shock, and 7 patients (12%) had coronary artery dilatation.Thirty-six patients (56%) had gastrointestinal symptoms, 23 patients (36%) had neurological symptoms. Forty-five patients (70%) received the initial treatment of intravenous immunoglobulin in combination with glucocorticoids, 5 patients (8%) received the methylprednisolone pulse therapy and 2 patients (3%) treated with biological agents, 7 patients with coronary artery dilation all returned to normal within 6 months. Conclusions: MIS-C patients are mainly characterized by fever, high inflammatory response, and multiple organ damage. The preferred initial treatment is intravenous immunoglobulin combined with glucocorticoids. All patients have a good prognosis.
Male ; Child ; Female ; Humans ; Immunoglobulins, Intravenous/therapeutic use* ; Blood Coagulation ; COVID-19 ; China/epidemiology* ; Connective Tissue Diseases ; Coronary Aneurysm ; Fever ; Systemic Inflammatory Response Syndrome/therapy*

The kidney is the body's most important organ and the protein components in urine could be detected for diagnosing certain diseases. The amount of IgG protein in urine could be used to determine the degree of kidney function damage. IgG protein in human urine was detected by vertical flow paper-based microfluidic chip, double-antibody sandwich immunoreaction, and cell phone image processing. The results showed that using an IgG antibody concentration of 500 μg/mL and a gold standard antibody concentration of 100 μg/mL, the image signal showed a good linear relationship in the range of IgG concentration of 0.2-3.2 μg/mL, with R²=0.973 3 achieved. A complete set of detection devices were designed and the detection method showed good non-specificity.
Humans ; Microfluidics ; Immunoglobulin G ; Kidney ; Microfluidic Analytical Techniques

OBJECTIVES: To study the expression of interleukin-17A (IL-17A) in the serum of children with intravenous immunoglobulin (IVIG)-resistant Kawasaki disease (KD) and its clinical significance. METHODS: A total of 143 children with KD who were hospitalized in Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, from June 2021 to June 2022 were enrolled in this prospective study, among whom 115 had IVIG-sensitive KD and 28 had IVIG-resistant KD. After matching for sex and age, 110 children with acute respiratory infectious diseases (fever time ≥5 days but without KD) were enrolled as the control group. The enzyme-linked immunosorbent assay was used to measure the serum level of IL-17A. The levels of white blood cell count (WBC), neutrophil count (NE), platelet count, erythrocyte sedimentation rate, and C-reactive protein (CRP) were measured. The receiver operating characteristic curve was plotted to analyze the value of WBC, NE, CRP, and IL-17A in the prediction of IVIG-resistant KD. The multivariate logistic regression analysis was used to evaluate the predictive factors for resistance to IVIG in children with KD. RESULTS: Before IVIG treatment, the KD group had a significantly higher serum level of IL-17A than the control group (P<0.05), and the children with IVIG-resistant KD had a significantly higher serum level of IL-17A than those with IVIG-sensitive KD (P<0.05). The receiver operating characteristic curve analysis showed that WBC, NE, CRP, and IL-17A had an area under the curve of 0.718, 0.741, 0.627, and 0.840, respectively, in the prediction of IVIG-resistant KD. With serum IL-17A ≥44.06 pg/mL as the cut-off value, IL-17A had a sensitivity of 84% and a specificity of 81% in the prediction of IVIG-resistant KD. The multivariate logistic regression analysis showed that a high serum level of IL-17A was a predictive factor for resistance to IVIG in children with KD (OR=1.161, P=0.001). CONCLUSIONS Serum IL-17A levels are elevated in children with IVIG-resistant KD, and serum IL-17A level (≥44.06 pg/mL) may have a predictive value for resistance to IVIG in children with KD.
Humans ; Child ; Infant ; Aged, 80 and over ; Immunoglobulins, Intravenous/therapeutic use* ; Mucocutaneous Lymph Node Syndrome/drug therapy* ; Interleukin-17 ; Clinical Relevance ; Prospective Studies ; C-Reactive Protein/analysis* ; Retrospective Studies