Objective To analyze the changes of immune indicators in patients with systemic lupus erythematosus(SLE)and explore their correlation with lupus nephritis(LN).Methods A total of 109 SLE patients treated in Affiliated Lihuili Hospital of Ningbo University from November 2021 to October 2023 were retrospectively included in SLE group,SLE patients were divided into LN group(56 cases)and non-LN group(53 cases)according to whether they were diagnosed with LN or not.32 healthy people who underwent physical examination in the hospital during the same period were included in healthy control group.The immune indicators of subjects were detected,and the clinical data and the scores of systemic lupus erythematosus disease activity index 2000(SLEDAI-2000)were collected.Spearman correlation method was used to analyze correlation between SLEDAI-2000 scores and immune indicators in SLE patients.Multivariate Logistic regression was used to analyze the influencing factors of LN in SLE patients.Results The total lymphocyte count,T cell count,natural killer(NK)cell count,B cell count,helper T(Th)cell proportion,NK cell proportion,B cell proportion,immunoglobulin(Ig)M,complement C3 and complement C4 in SLE group were significantly lower than those in healthy control group(P<0.05),T cell proportion,suppressor T(Ts)cell proportion and anti-double-stranded DNA antibody IgG were significantly higher than those in healthy control group(P<0.05).SLEDAI-2000 scores in SLE group were negatively correlated with NK cell count,B cell count and NK cell proportion(P<0.05),and were positively correlated with T cell proportion and Ts cell proportion(P<0.05).The NK cell count,B cell count,NK cell proportion and B cell proportion in LN group were significantly lower than those in non-LN group(P<0.05),T cell proportion,anti-double-stranded DNA antibody IgG and SLEDAI-2000 scores were significantly higher than those in non-LN group(P<0.05).Multivariate Logistic regression analysis showed that NK cell count and SLEDAI-2000 scores were all factors influencing the development of LN in SLE patients(P<0.05).Conclusion Immune indicators have the ability to evaluate the disease status of SLE patients.SLE patients with decreased NK cell count and increased SLEDAI-2000 scores are more likely to develop LN.

Objective Study on the reduction of false positive interference in the detection of human immunodeficiency virus(HIV)by chemiluminescence method with polyethylene glycol(PEG)precipitation.Methods A total of 109 outpatients and inpatients in Ningbo Medical Center,Lihuili Hospital from January to June 2022 were selected.The positive samples initially screened by chemiluminescence method were confirmed by Western blotting,and 20 true positive samples and 89 false positive samples were confirmed.According to whether treatment agent was added,the false-positive samples were divided into three groups:no PEG precipitation group(no special treatment,89 cases),PEG precipitation group(PEG precipitation treatment,89 cases)and control group(normal saline treatment,89 cases).The level of HIV antigen/antibody(Ag/Ab)in supernatant was measured after centrifugation,and the difference of HIV Ag/Ab level and recovery rate before and after different treatment methods were compared.Results After intervention,the HIV Ag/Ab concentration in PEG precipitation group and control group was significantly lower than that in non-PEG precipitation group(P<0.001).After intervention,there were 3 positive cases in PEG precipitation group and 56 positive cases in control group,and the positive rates were significantly lower than those in non-PEG precipitation group(P<0.001).The recovery rate of PEG precipitation group was 4.92(2.12,12.69)%,and that of control group was 65.28(18.04,91.28)%.The recovery rate of true positive samples was>50%regardless of PEG treatment or normal saline treatment.Conclusion PEG precipitation method can effectively reduce the false positive interference of chemiluminescent HIV fourth-generation reagent detection,and has no effect on true positive samples.