A retrospective analysis was conducted on the clinical characteristics, renal pathology, genetic testing, and treatment of five patients —two males and three females—diagnosed with primary atypical hemolytic uremic syndrome (aHUS) in the Department of Nephrology at the Affiliated Hospital of Qingdao University from February 2022 to June 2024. The patients′ ages at disease onset ranged from 14 to 29 years. Four patients experienced prodromal infection symptoms. At disease onset, serum creatinine levels ranged from 168.5 to 1 230.2 μmol/L. All patients presented with hematuria, proteinuria, hypertension, non-immune hemolytic anemia, thrombocytopenia, elevated lactate dehydrogenase (LDH), and fragmented red blood cells in peripheral blood (0.5%-6.0%). Serum haptoglobin levels were below the normal lower limit in all cases. Four patients demonstrated decreased serum complement C3, while one maintained normal serum complement C3 throughout the course of the disease. One patient exhibited serum factor H concentrations below the normal lower limit. Another patient tested positive for anti-factor H antibodies. Renal biopsies were performed on four patients. Electron microscopy revealed typical acute-phase pathological features of aHUS in three cases, including glomerular endothelial cell swelling and widened subendothelial spaces. One patient demonstrated ischemic and atrophic changes in the glomerular capillaries, while another had concurrent membranous nephropathy. Whole-exome high-throughput sequencing related to aHUS was performed in all five patients, revealing heterozygous gene mutations in each case. Complement-related gene mutations, typically occurring in a heterozygous state, are prevalent in aHUS patients. The eight heterozygous gene variations identified in this study were absent from existing databases of known aHUS-associated pathogenic mutations. Four patients received eculizumab treatment at varying time points following diagnosis, resulting in differing clinical outcomes. The patient positive for anti-factor H antibodies was treated with rituximab. The patient with membranous nephropathy initiated combination therapy with rituximab and eculizumab after six months of eculizumab monotherapy. Following treatment, all five patients achieved complete cessation of intravascular mechanical hemolysis, with normalization of LDH and platelet levels, as well as varying degrees of renal function recovery. From a pathophysiological perspective, the timely administration of the complement C5 inhibitor eculizumab can rapidly induce clinical remission, reduce the incidence of end-stage renal disease, and improve prognosis in patients with aHUS.

A retrospective analysis was conducted on the clinical characteristics, renal pathology, genetic testing, and treatment of five patients —two males and three females—diagnosed with primary atypical hemolytic uremic syndrome (aHUS) in the Department of Nephrology at the Affiliated Hospital of Qingdao University from February 2022 to June 2024. The patients′ ages at disease onset ranged from 14 to 29 years. Four patients experienced prodromal infection symptoms. At disease onset, serum creatinine levels ranged from 168.5 to 1 230.2 μmol/L. All patients presented with hematuria, proteinuria, hypertension, non-immune hemolytic anemia, thrombocytopenia, elevated lactate dehydrogenase (LDH), and fragmented red blood cells in peripheral blood (0.5%-6.0%). Serum haptoglobin levels were below the normal lower limit in all cases. Four patients demonstrated decreased serum complement C3, while one maintained normal serum complement C3 throughout the course of the disease. One patient exhibited serum factor H concentrations below the normal lower limit. Another patient tested positive for anti-factor H antibodies. Renal biopsies were performed on four patients. Electron microscopy revealed typical acute-phase pathological features of aHUS in three cases, including glomerular endothelial cell swelling and widened subendothelial spaces. One patient demonstrated ischemic and atrophic changes in the glomerular capillaries, while another had concurrent membranous nephropathy. Whole-exome high-throughput sequencing related to aHUS was performed in all five patients, revealing heterozygous gene mutations in each case. Complement-related gene mutations, typically occurring in a heterozygous state, are prevalent in aHUS patients. The eight heterozygous gene variations identified in this study were absent from existing databases of known aHUS-associated pathogenic mutations. Four patients received eculizumab treatment at varying time points following diagnosis, resulting in differing clinical outcomes. The patient positive for anti-factor H antibodies was treated with rituximab. The patient with membranous nephropathy initiated combination therapy with rituximab and eculizumab after six months of eculizumab monotherapy. Following treatment, all five patients achieved complete cessation of intravascular mechanical hemolysis, with normalization of LDH and platelet levels, as well as varying degrees of renal function recovery. From a pathophysiological perspective, the timely administration of the complement C5 inhibitor eculizumab can rapidly induce clinical remission, reduce the incidence of end-stage renal disease, and improve prognosis in patients with aHUS.

Objective:To investigate the clinical value of dynamic detection of lymphocyte subsets and blood cell counts in management of patients with lupus nephritis (LN).Methods:The clinical data of 65 patients with primary LN admitted in Affiliated Hospital of Qingdao University from January 2015 to April 2021 were retrospectively analyzed. According to the stage of disease progression and medications used,LN patients were classified into primary active phase,post-induction therapy phase,and maintenance therapy phase. The changes in lymphocyte subsets were monitored,and the relationship of lymphocyte subsets and blood cell count ratios with lupus activity and infection events was evaluated.Results:The decrease of CD4 +T lymphocyte and NK cell counts were negatively correlated with the activity of systemic lupus erythematosus (SLE)( r=-0.67,-0.33, P<0.01),while CD8 +T lymphocyte,B cell counts,neutrophil/lymphocyte ratio (NLR),platelet/lymphocyte ratio (PLR),and monocyte/lymphocyte ratio (MLR) were positively correlated with the SLE activity( r=0.38,0.26,0.34,0.26,0.29, P<0.05). The area under ROC curve (AUC) of CD4 +T lymphocyte count in predicting the occurrence of infection in LN patients was the highest (0.89); taking 247.50 cell/μl as cutoff value,the sensitivity and specificity were 81.25% and 87.50%,respectively. The combination of CD4 +T lymphocyte with CRP increased the predicting value for the occurrence of infection. Conclusion:Dynamic detection of blood lymphocyte subsets and blood cell counts can reflect SLE activity and the occurrence of infection in LN patients. Among these indicators the CD4 +T lymphocyte has the highest predictive value for the occurrence of infection,and the combination of the CD4 +T lymphocyte count with CRP level can further improve the predicting value.

Objective To investigate the pathogenesis of the production of anti-neutrophil cytoplasmic antibodies (ANCA) in the rat models of chronic bronchitis (CB) with recurrent infections. Methods The CB models were made by double element of smoking and lipopolysaccharide (LPS) stimulation. The rats were divided into four groups, including normal control group (n=5), phorbol-12-myristate-13-acetate (PMA)-treated healthy rats control group (n=5), CB rats group (n=5) and PMA-treated CB rats group (n=6). Renal function of rats was detected. The histopathological lung and kidney tissues were observed by HE staining of paraffin section. Immunological markers, including myeloperoxidase anti-neutrophil cytoplasmic antibodies (MPO-ANCA), proteinase 3 anti-neutrophil cytoplasmic antibodies (PR3-ANCA) and citrullinated histone H3 (CitH3), were measured by enzyme-linked immune-sorbent assay (ELISA) at different time points. Correlation between CitH3 and MPO-ANCA was analyzed by the Spearman rank correlation. NETs components were further detected in lung and kidney tissue by confocal immunofluorescence and colocalization analysis. Results (1) The serum levels of CitH3 and MPO-ANCA in CB+PMA group showed an increased trend. Compared with those in the normal control group and CB rats group, the serum levels of CitH3 and MPO-ANCA in CB+PMA group increased significantly at the sixth week (both P＜0.05). Serum CitH3 levels in rats were positively correlated with serum MPO-ANCA levels (rs=0.490,P=0.024). (2) There were pathological manifestations of CB in the lung tissues of rats in CB group and CB+PMA group, and no obvious abnormalities in the lung tissues of rats in the normal control group and control group. In the rat kidney tissue of CB+PMA group, there were inflammatory cells infiltrated in the glomerular and around the renal tubules, but glomerular necrosis was not found. No obvious abnormalities were observed in the kidney tissues of rats in the normal control group, PMA-treated healthy rats control group and CB group. (3) In the lung and kidney tissues of CB+PMA group NETs could be detected by confocal immunofluorescence analysis. Conclusion CB rats with the recurrent infections can release large amounts of NETs, in which the exposure of MPO antigen will break the immune tolerance and result in the production of MPO-ANCA.

Objective To explore the significance of peptidylarginine deiminase type 4 (PAD4) in the pathogenesis of ANCA-associated vasculitis (AAV) by detecting its level in patients with AAV.Methods Sera from 13 patients with AAV,11 patients with primary chronic kidney disease and 12 healthy controls were collected.Serum PAD4 was detected using commercial ELISA kits.The association between serum PAD4 and BVAS of AAV was further investigated.Results (1) The serum level of PAD4 in patients with AAV in active and remission stages were all higher than that in the healthy controls.The serum level of PAD4 in patients with CKD was not found elevated compared with the normal controls.(2) The serum levels of PAD4 in AAV with renal damage were all significantly higher than that in CKD group no matter in active or remission stage.(3) The serum level of PAD4 in AAV with renal damage in active stage was positively correlated with BVAS (r=0.71,P=0.02).Conclusion PAD4 is involved in the pathogenesis of AAV.

Objective To investigate the association of expressions of neutrophil extracellular trap (NET) and B lymphocyte in renal tissue with lupus activity in patients with lupus nephritis (LN). Methods Immunohistochemistry was.used to detect the expression of NET (citrullinated histone H3 as the marker) and the infiltration of B lymphocyte (CD19 as the marker)in renal specimens of three groups [LN group,n=20; minimal change disease (MCD) group,n=8;healthy control group,n=3].The chronic index and SLE-disease activity index (SLE-DAI) in renal tissues of LN and their correlations with NET and B lymphocytes were examined. Results The expression of NET was not found in the renal tissues of healthy control group and MCD group,while it increased significantly in LN group,especially in glomeruli with moderate and severe mesangial cells proliferation, cellular crescents, and tubulointerstitium with inflammatory cell infiltration.Compared with other types of glomeruli,the expression of NET was significantly upregulated in glomeruli with moderate and severe mesangial cell proliferation (P＜0.01).In the glomeruli with moderate and severe glomerular mesangial cell proliferation,the mean number of =NET positive cells was positively correlated with renal pathological active index (r=0.620,P=0.004),the score of SLE-DAI (r=0.492,P=0.027) and the mean number of NET positive tubular cells (r=0.558,P=0.011).In renal interstitium,the NET positive cells were positively correlated with CD19 positive B lymphocytes (r=0.573,P=0.008) and renal pathological chronic index (r=0.645,P=0.002). Conclusion NET is widely expressed in the renal tissues of lupus nephritis,which may play a role in the active damage of glomeruli.

To reveal the involvement of oxidative stress in hypertension and insulin resistance. Angiotensin Ⅱ was given to adrenomedullin-knockout mice for 4 weeks. 4-Hydroxy-TEMPOL, a superoxide scavenger mimetic was also employed. The results suggested that adrenomedullin may exert a protective effect against insulin resistance via its intrinsic antioxidant effect.