Résumé
Objective:To explore the relationship between the levels of serum complement C3 and C4 and the degree of renal pathological injury in patients with IgA nephropathy (IgAN).Methods:It was a retrospective study. The clinical and pathological data of patients with primary IgAN diagnosed by renal biopsy in the Department of Nephrology of the Second People's Hospital of Qujing City, Yunnan Province from December 1, 2019 to December 31, 2022 were collected. According to the IgAN Oxford classification criteria, the patients were divided into mild renal pathological injury group (mild group, <3 pathologic types) and severe renal pathological injury group (severe group, ≥3 pathological types). The levels of serum C3 and C4 and other clinical data were compared between the two groups. Spearman correlation method was used to analyze the correlation between serum C3, C4 levels and estimated glomerular filtration rate (eGFR) during renal biopsy.Multivariate logistic regression model was used to analyze the influencing factors of the pathological injury degree in IgAN patients and the forest map depicted the effect of risk factors.Results:A total of 164 IgAN patients were included in the study, including 77 males (47.0%), aged (35.5±12.9) years old. There were 60 patients in the mild group and 104 patients in the severe group. Compared with the mild group, the patients in the severe group were older, had higher levels of serum C4, serum uric acid, low density lipoprotein cholesterol and 24 h urinary protein, higher proportions of hypertension, glucocorticoids/immunosuppressant therapy, C3 deposition in renal tissues and microscopic hematuria, and had lower hemoglobin and serum C3 level (all P<0.05). The results of Spearman correlation analysis showed that the level of serum C3 was positively correlated with eGFR ( r=0.303, P<0.001), and the level of serum C4 was negatively correlated with eGFR ( r=-0.238, P=0.002). Multivariate logistic regression analysis results showed that serum C3 (every 0.01 g/L increase, OR=0.976, 95% CI 0.957-0.996, P=0.018), serum C4 (every 0.01 g/L increase, OR=1.091, 95% CI 1.020-1.166, P=0.011), hemoglobin ( OR=0.969, 95% CI 0.950-0.988, P=0.002), and serum uric acid ( OR=1.005, 95% CI 1.001-1.009, P=0.012) were independent related factors of renal pathological damage (severe injury /mild injury) in IgAN patients. Conclusions:Serum C3 and C4 are independent related factors of the severity of renal pathological injury in IgAN patients.
Résumé
Objective To investigate the clinical characteristics and risk factors of secondary infection in patients with anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV).Methods One hundred and eighteen patients newly diagnosed with AAV at the institute of nephrology,Tongji hospital affiliated to Huazhong university of science and technology,from 2012 to 2017,were analyzed retrospectively.Induction therapy included single corticosteroids,combination of corticosteroids with cyclophosphamide and combination of corticosteroids with other immunosuppressive agents.End point was defined as moderate to severe infection which was diagnosed by the clinical and radiological manifestation as well as microbiological evidences.The infection-related survival curve was drawn to reflect the time when the infection occurred.The clinical baseline variables in patients with and without infection were compared.Multivariate Logistic regression model was used to determine the independent predictors of infection.Receiver-operating characteristic curve (ROC) was plotted for evaluating the predictive value of lymphocyte on moderate to severe infection.Results During followup of median 3 months (1-30 months),88 infection episodes were found in 63 (53.4％) patients,of which 54 times (61.4％) occurred within 6 months after treatment,46 times (52.3％) happened within 3 months after treatment.The most common organ of infection was lung (62.5％),and the most common pathogen was bacteria (51.1％).Multivariate Logistic regression model showed that lung involvement (OR=4.44,95％ CI 1.59-12.41),moderate reduction of lymphocyte in follow-up (OR=5.69,95％ CI 2.05-15.85) and severe lymphocyte reduction (OR=36.28,95％CI 3.45-381.17) were independent risk factors of secondary infection in AAV patients (all P ＜ 0.05).ROC curve showed that the area under the curve of lymphocyte as a predictor of severe infection was 0.767 (95％ CI 0.64-0.89,P ＜ 0.05).Based on lymphocyte less than 0.49× 109/L which was the cut-off value for predicting severe infection,the sensitivity and the specificity were 83.9％ and 71.9％,respectively.Conclusions Lung involvement and moderate-severe lymphopenia during follow-up are independent risk factors of secondary infection in AAV patients.Hence,physician should pay more attention to those patients,and adjust treatment in time to avoid the occurrence of infection.