OBJECTIVES: To investigate the clinical and immunological features of children with primary immune thrombocytopenia (pITP) or connective tissue disease (CTD) with thrombocytopenia as the initial manifestation at initial diagnosis, and to provide a basis for early differentiation. METHODS: A retrospective study was performed on 236 children with pITP (pITP group) or CTD with thrombocytopenia as the initial manifestation (CTD-TP group) who were admitted from January 2019 to August 2024. Clinical and immunological indicators were compared between the two groups to identify potential influencing factors for early differentiation and their discriminative validity. RESULTS: Compared with the pITP group, the CTD-TP group had a significantly older age of onset and significantly lower leukocyte count, eosinophil count, lymphocyte count, and complement C4 level (P<0.05), as well as significantly higher levels of C-reactive protein, IgE, and IgM (P<0.05). The logistic regression analysis showed that age, IgE, IgM, total B cells, and complement C4 were predictive factors for early differentiation between pITP and CTD-TP (P<0.05). The receiver operating characteristic curve analysis showed that a combination of these five factors had a good discriminative validity, with an area under the curve of 0.944. The correlation analysis showed a negative correlation between IgG and platelet count in the pITP group (r_s=-0.363, P<0.05) and a positive correlation between NK cells and platelet count in the CTD-TP group (r_s=0.713, P<0.05). CONCLUSIONS There is heterogeneity in the clinical and immunological indicators between children with pITP and CTD-TP at initial diagnosis, and these research findings can help with the early differentiation between the two diseases.
Purpura, Thrombocytopenic, Idiopathic/immunology* ; Diagnosis, Differential ; Connective Tissue Diseases/immunology* ; Retrospective Studies ; Early Diagnosis ; Age of Onset ; Leukocyte Count ; Complement C4/immunology* ; C-Reactive Protein/immunology* ; Immunoglobulin E/immunology* ; Immunoglobulin M/immunology* ; Humans ; Male ; Female ; Infant ; Child, Preschool ; Child ; Adolescent ; Biomarkers/blood*

OBJECTIVE: To explore the relationship between serum complement levels at diagnosis and prognosis in patients with aggressive non-Hodgkin lymphoma(NHL). METHODS: The clinical data of 102 patients with aggressive non-Hodgkin lymphoma diagnosed in the First Hospital of Lanzhou University from February 2017 to March 2023 were selected to analyze the correlation between serum complement C3 and C4 levels and prognosis of patients with aggressive NHL at the time of initial diagnosis. The optimal cut-off point of C3 and C4 were obtained by calculating the Jorden index through the receiver operating characteristic（ROC） curve, and 102 patients were divided into low C3 group (C3< 1.07) and high C3 group (C3≥1.07), low C4 group (C4< 0.255) and high C4 group (C4≥0.255). The effects of serum C3 and C4 levels on the prognosis of these patients were analyzed. RESULTS: ROC curve analysis showed that the area under the curve (AUC) of C3 and C4 in predicting the prognosis of aggressive NHL patients was 0.634 (95%CI ：0.525-0.743；P =0.025) and 0.651 (95%CI ：0.541-0.761；P =0.012), respectively. The optimal cut-off points for C3 and C4 were 1.07 and 0.255, respectively. K-M survival analysis showed that groups with high C3 and C4 levels had shorter progression-free survival (PFS) (P =0.0079; P =0.0092) and overall survival (OS) (P =0.021; P =0.021). Multivariate Cox analysis showed that high level serum complement C3 (HR=2.37, 95%CI : 1.07-5.24, P =0.034) and age ≥60 years (HR=2.34, 95%CI : 1.11-4.95, P =0.025) were independent risk factors for PFS in patients with aggressive NHL. High level complement C3 (HR=2.37, 95%CI : 1.09-5.13, P =0.029) and age ≥60 years at diagnosis (HR=2.40, 95%CI : 1.13-5.13, P =0.024) were independent risk factors for OS in patients with aggressive NHL. CONCLUSION The level of serum complement C3 at diagnosis is one of the prognostic factors in patients with aggressive NHL.
Humans ; Lymphoma, Non-Hodgkin/blood* ; Prognosis ; Complement C3/metabolism* ; Complement C4/metabolism* ; ROC Curve ; Male ; Female ; Middle Aged ; Adult ; Aged

OBJECTIVE: To stratify systemic lupus erythematosus (SLE) patients clinically, to analyze the clinical characteristics of patients with and without disease activity, and to explore the application va-lue of key clinical indicators in assessing disease activity, as well as to construct an evaluation model. METHODS: A retrospective analysis was conducted on clinical data of the SLE patients diagnosed at Peking University People' s Hospital from May 1995 to April 2014. Demographic information, clinical manifestations, laboratory tests, and antibody detection results were collected. The patients were divided into active and inactive groups based on systemic lupus erythematosus disease activity index 2000(SLEDAI-2000)scores. t-tests, Mann-Whitney U tests, and χ² tests were used to compare the differences between the groups. Spearman correlation analysis was used to evaluate the relevant clinical indicators associated with SLE activity in the active disease group. Based on the results of statistical analysis, a Logistic regression model was constructed, and the performance of the model was evaluated. RESULTS: No significant differences were found in demographic characteristics between the two groups. In the active disease group, positive rates of antinuclear antibodies (ANA) and anti-double-stranded DNA antibodies (anti-dsDNA) were increased; white blood cell count (WBC), red blood cell count (RBC), hemoglobin (HGB), lymphocytes (LY), total protein (TP), albumin (ALB), and complement 3(C3) levels were significantly decreased; while immunoglobulin A and G levels were markedly elevated. The correlation analysis results showed that hemoglobin, albumin, C3, and complement 4(C4) had higher correlation indices compared with other clinical indicators. Among these, C3 exhibited a certain negative correlation with disease activity. The Logistic regression model based on 12 significantly different indicators (P < 0.05) achieved an accuracy of 91.4%, sensitivity of 94.4%, specificity of 81.0%, and the area under curve (AUC) of the receiver operating characteristic (ROC) was 0.944. CONCLUSION This study comprehensively evaluated a range of clinical indicators related to SLE disease activity, providing a thorough understanding of both laboratory and clinical markers. The Logistic regression model, which was primarily constructed using laboratory test indicators, such as inflammatory markers, immune response parameters, and organ involvement metrics, demonstrated a high degree of accuracy in assessing the disease activity in SLE patients. Consequently, this model might provide a new basis for the diagnosis and treatment of SLE patients, offering significant clinical diagnostic value.
Humans ; Lupus Erythematosus, Systemic/diagnosis* ; Retrospective Studies ; Antibodies, Antinuclear/blood* ; Complement C3/metabolism* ; Complement C4/metabolism* ; Logistic Models ; Severity of Illness Index ; Leukocyte Count ; Female ; Male ; Serum Albumin/analysis*

OBJECTIVE: To investigate the risk factors of different types of Henoch-Schönlein purpura (HSP) in Tibetan patients at high altitude, as to provide reference for correctly identifying high-risk patients. METHODS: A retrospective study was used to analyze the 304 HSP patients admitted to Tibet Autonomous Region People's Hospital from April 2014 to March 2022. The gender, age, allergic history, family history, clinical type, laboratory indexes (hemoglobin, platelet count, eosinophil, C-reactive protein (CRP), albumin, immunoglobulin G, immunoglobulin A, complement C3 and C4) were analyzed retrospectively. Univariate and multivariate Logistic regression analysis to screen for risk factors affecting different types of HSP. RESULTS: Renal HSP patients showed higher IgA [(9.2±1.7) g/L vs. (6.4±2.4) g/L, P=0.015], lower complement C3 [(203.3±21.6) mg/dL vs. (301.1±19.5) mg/dL, P=0.043], and complement C4 [(33.5±2.3) mg/dL vs. (53.0±7.2) mg/dL, P=0.032]. The patients with abdominal HSP showed lower levels of hemoglobin [(119.6±19.6) g/L vs. (146.6±47.3) g/L, P=0.038] and plasma albumin [24.8 (22.1, 33.9) g/L vs. 32.6 (24.6, 35.1) g/L, P=0.045]. The patients with articular HSP exhibited higher CRP [13.5 (0.2, 20.6) g/L vs. 7.5 (0.1, 15.2) g/L, P=0.036] and erythrocyte sedimentation rate (ESR) [24 (5, 40) mm/h vs. 15 (4, 30) mm/h, P=0.049]. Elevated IgA and decreased complement C4 were risk factors for renal HSP, anemia and decreased plasma albumin were risk factors for abdominal HSP, and elevated CRP was a risk factor for articular HSP. CONCLUSION The clinical characteristics of different types of HSP in plateau areas were different. Patients with high IgA, low complement C4, anemia, hypoalbuminemia, and significantly elevated CRP should be highly vigilant. Early and effective intervention can improve the clinical efficacy, avoid severe development, and improve the prognosis.
Humans ; Retrospective Studies ; Tibet/epidemiology* ; Complement C3/analysis* ; IgA Vasculitis/complications* ; Altitude ; Complement C4 ; C-Reactive Protein/analysis* ; Immunoglobulin A ; Risk Factors ; Anemia ; Hemoglobins/analysis* ; Serum Albumin/analysis*

BACKGROUND: The complement system plays an important role in the immune response to transplantation, and the diagnostic significance of peritubular capillary (PTC) C4d deposition (C4d+) in grafts is controversial. The study aimed to fully investigate the risk factors for PTC C4d+ and analyze its significance in biopsy pathology of kidney transplantation. METHODS: This retrospective study included 124 cases of kidney transplant with graft biopsy and donor-specific antibody (DSA) testing from January 2017 to December 2019 in a single center. The effects of recipient pathological indicators, eplet mismatch (MM), and DSAs on PTC C4d+ were examined using univariate and multivariate logistic regression analyses. RESULTS: In total, 35/124 (28%) were PTC C4d+, including 21 with antibody-mediated rejection (AMR), eight with renal tubular injury, three with T cell-mediated rejection, one with glomerular disease, and two others. Univariate analysis revealed that DSAs (P < 0.001), glomerulitis (P < 0.001), peritubular capillaritis (P < 0.001), and human leukocyte antigen (HLA) B eplet MM (P = 0.010) were the influencing factors of PTC C4d+. According to multivariate analysis, DSAs (odds ratio [OR]: 9.608, 95% confidence interval [CI]: 2.742-33.668, P < 0.001), glomerulitis (OR: 3.581, 95%CI: 1.246-10.289, P = 0.018), and HLA B eplet MM (OR: 1.166, 95%CI: 1.005-1.353, P = 0.042) were the independent risk factors for PTC C4d+. In receiver operating characteristic curve analysis, the area under the curve was increased to 0.831 for predicting PTC C4d+ when considering glomerulitis, DSAs, and HLA B eplet MM. The proportions of HLA I DSAs and PTC C4d+ in active antibody-mediated rejection were 12/17 and 15/17, respectively; the proportions of HLA class II DSAs and PTC C4d+ in chronic AMR were 8/12 and 7/12, respectively. Furthermore, the higher the PTC C4d+ score was, the more serious the urinary occult blood and proteinuria of recipients at the time of biopsy. CONCLUSIONS PTC C4d+ was mainly observed in AMR cases. DSAs, glomerulitis, and HLA B eplet MM are the independent risk factors for PTC C4d+.
Allografts ; Biopsy ; Complement C4b ; Graft Rejection ; HLA Antigens ; HLA-B Antigens ; Humans ; Kidney Transplantation/adverse effects* ; Peptide Fragments ; Retrospective Studies ; Risk Factors

To study the interaction between C4b-binding protein (C4BP) and Riemerella anatipestifer (RA), we cloned duck C4BPα, conducted prokaryotic expression and prepared the polyclonal antibody by immunizing mice. Then indirect immunofluorescence assay and dot blotting hybridization assay were used to verify the interaction between C4BP and RA. The full length of duck C4BPα nucleotide sequence was 1 230 bp, with the highest similarity to chicken C4BPα (82.1%). Phylogenetic tree analysis showed that duck C4BPα and chicken C4BPα were on the same phylogenetic tree branch and the genetic evolution relationship between them was the closest. C4BPα was efficiently expressed in Escherichia coli BL21 (DE3). The recombinant proteins existed in intracellular soluble form. The titer of polyclonal antibody was more than 1:10 000 and polyclonal antibodies could specifically recognize the recombinant proteins. The results of indirect immunofluorescence assay and dot blot hybridization assay showed that RA could interact with duck C4BP. The results provide a basis to further reveal the pathogenesis of RA.
Animals ; Cloning, Molecular ; Complement C4b-Binding Protein ; chemistry ; genetics ; metabolism ; Ducks ; classification ; genetics ; microbiology ; Gene Expression Regulation ; Mice ; Phylogeny ; Riemerella ; metabolism

OBJECTIVE: To study the expression and diagnostic value of plasma miR-145 and miR-183 in children with lupus nephritis (LN). METHODS: A total of 92 children with LN who were admitted from January 2016 to May 2019 were enrolled as the LN group, among whom 17 had type II LN, 15 had type III LN, 36 had type IV LN, 18 had type V LN, and 6 had type VI LN. Forty healthy children who underwent physical examination were enrolled as the healthy control group. According to Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), the 92 children with LN were further divided into a stable LN group with 34 children (SLEDAI score <10) and an active LN group with 58 children (SLEDAI score ≥10). RT-PCR was used to measure the expression of miR-145 and miR-183 in plasma. The receiver operating characteristic (ROC) curve was used to analyze the value of plasma miR-145, miR-183, and anti-dsDNA antibody in the diagnosis of LN. Pearson correlation analysis was used to investigate the correlation of the expression levels of miR-145 and miR-183 in plasma with laboratory markers. RESULTS: The LN, active LN, and stable LN groups had significantly higher levels of anti-dsDNA antibody, C-reactive protein, serum creatinine (Scr), and blood urea nitrogen (BUN) than the control group (P<0.05). The active LN group had significantly higher SLEDAI score, anti-dsDNA antibody, Scr, and BUN than the stable LN group (P<0.05). The LN, active LN, and stable LN groups had significantly lower levels of complement C3, complement C4, and serum albumin (Alb) than the control group (P<0.05). The active LN group had a significantly lower level of Alb than the stable LN group (P<0.05). The LN, active LN, and stable LN groups had significantly lower plasma levels of miR-145 and miR-183 than the control group (P<0.01). The active LN group had significantly lower plasma levels of miR-145 and miR-183 than the stable LN group (P<0.01). The children with difference types of LN had significantly lower plasma levels of miR-145 and miR-183 than the control group (P<0.01), and the type V-VI group and the type IV group had significantly lower plasma levels of miR-145 and miR-183 than the type II-III group (P<0.01). The ROC curve analysis showed that the optimal cut-off values of plasma miR-145, miR-183, and anti-dsDNA antibody were 1.05, 0.62, and 186.30 IU/mL respectively, in the diagnosis of LN, and the combination of these three indices had the largest area under the ROC curve of 0.896 (95%CI: 0.835-0.955), with a sensitivity of 90.5% and a specificity of 84.2%. In the children with LN, the plasma levels of miR-145 and miR-183 were negatively correlated with SLEDAI score, anti-dsDNA antibody, Scr, and BUN (P<0.05) and were positively correlated with complement C3, complement C4, and Alb (P<0.05). CONCLUSIONS There are significant reductions in the expression levels of miR-145 and miR-183 in plasma in children with LN, which are correlated with the activity level and pathological typing of LN. Combined measurement of miR-145, miR-183, and anti-dsDNA antibody has a high value in the diagnosis of LN.
Biomarkers ; Child ; Complement C4 ; Humans ; Lupus Nephritis ; genetics ; MicroRNAs ; genetics ; ROC Curve

OBJECTIVE: To study the clinical value of lymphocyte subsets, immunoglobulins, and complement C3 and C4 in the evaluation of immune status in children with hand-foot-mouth disease (HFMD). METHODS: A total of 282 children with HFMD were enrolled as the HFMD group, and 130 healthy children were enrolled as the healthy control group. The percentages of peripheral CD3, CD4, and CD8 T lymphocytes, CD19 B lymphocytes, and CD56 natural killer cells were measured. The CD4/CD8 ratio was calculated. The levels of immunoglobulin A (IgA), immunoglobulin M (IgM), immunoglobulin G (IgG), and complement C3 and C4 were measured. RESULTS: The multivariate analysis showed that compared with the healthy control group, the HFMD group had significantly lower percentages of CD3, CD4, and CD8 T lymphocytes and levels of complement C3 and C4 (P<0.05), as well as significantly higher percentage of CD56 natural killer cells and level of IgG (P<0.05). The individual effect analysis showed that the children aged 0-3 years in the HFMD group had a significantly higher CD4/CD8 ratio than the healthy control group (P<0.05); boys aged 0-3 and ≥3 years in the HFMD group had a significantly higher level of IgM than the healthy control group (P<0.05); boys aged ≥3 years and girls aged 0-3 years in the HFMD group had a significantly lower level of IgA than the healthy control group (P<0.05). CONCLUSIONS Cellular and humoral immunity disorders are observed in children with HFMD. The monitoring of lymphocyte subsets and immunoglobulin levels can provide a laboratory basis for immune status assessment in children with HFMD.
Child, Preschool ; Complement C3 ; Complement C4 ; Female ; Hand, Foot and Mouth Disease ; Humans ; Immunoglobulins ; Infant ; Infant, Newborn ; Killer Cells, Natural ; Lymphocyte Count ; Lymphocyte Subsets ; Male

Atypical hemolytic uremic syndrome (aHUS), a rare form of thrombotic microangiopathy, is distinguished from the typical form by the absence of a preceding verotoxin-producing Escherichia coli infection. Notably, aHUS occurs in association with genetic or acquired disorders causing dysregulation of the alternative complement pathway. Patients with aHUS may show the presence of anti-complement factor H (CFH) autoantibodies. This acquired form of aHUS (anti-CFH-aHUS) primarily affects children aged 9–13 years. We report a case of a 13-year-old Lao girl with clinical features of aHUS (most likely anti-CFH-aHUS). The initial presentation of the patient met the classical clinical triad of thrombotic microangiopathy (microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury) without preceding diarrheal illness. Low serum levels of complement 3 and normal levels of complement 4 indicated abnormal activation of the alternative complement pathway. Plasma infusion and high-dose corticosteroid therapy resulted in improvement of the renal function and hematological profile, although the patient subsequently died of infectious complications. This is the first case report that describes aHUS (possibly anti-CFH-aHUS) in Laos.
Adolescent ; Anemia, Hemolytic ; Atypical Hemolytic Uremic Syndrome ; Autoantibodies ; Child ; Complement C3 ; Complement C4 ; Complement Factor H ; Complement Pathway, Alternative ; Female ; Humans ; Immunosuppression ; Kidney ; Laos ; Plasma ; Shiga-Toxigenic Escherichia coli ; Thrombocytopenia ; Thrombotic Microangiopathies

OBJECTIVE: To investigate the significance of detecting serum complement C3 and C4 in patients with multiple myeloma (MM) and to explore its correlation with myeloma bone disease (MBD). METHODS: The levels of serum complement C3 and C4 in 69 MM patients and 30 healthy people were examined by scatter nephelometry. The bone density of L1-4 vertebral body, bilateral femoral neck and bilateral hip joints were measured by dual energy bone density meter (DXA). RESULTS: The levels of serum complement C3 and C4 in MM patients significantly increased in comparison with that in healthy people (P＜0.01). The patients in advanced clinical stage exhibited a higher levels of C3 and C4 than those in stable stage (P＜0.01). In addition, the patients with grade C of MBD had a higher levels of serum complement C3 and C4 than those in patients with grade A and B of MBD (P＜0.01). The levels of serum complement C3 and C4 in MM patients negatively correlated with bone density in L1-4 vertebral body, bilateral femoral necks and hip joints. The correlation coefficients were r=-0.938, r=-0.659, r=-0.745, r=-0.748, r=-0.596 in complement C3 and r=-0.908, r=-0.623, r=-0.710, r=-0.714, r=-0.595 in complement C4, respectively. CONCLUSION The levels of complement C3 and C4 positively correlate with the severity of bone disease and bone density in MM patients, which suggests that complement C3 and C4 plays important roles in the development of MBD. The levels of serum C3 and C4 may be the sensitive biomarkers of MBD.
Biomarkers ; Complement C3 ; metabolism ; Complement C4 ; metabolism ; Femur Neck ; Humans ; Multiple Myeloma