Clinical Features Of 294 Children With IgA Vasculitis:A Retrospective Study

Background IgA vasculitis（IgAV）,formerly known as Henoch-Sch?nlein purpura（HSP）,is one of the most common forms of vasculitis in childhood.Typical clinical manifestations include non-thrombocytopenia skin purpura,joint swelling and pain,arthritis,abdominal pain,vomiting,gastrointestinal bleeding,and even hematuria and proteinuria.The incidence of the disease is higher in men than in women,and it is more common in winter and spring,and the peak age of onset is usually between 4 and 10 years old.The course of the disease is mostly self-limiting and the prognosis is good.Gastrointestinal involvement determines the short-term prognosis.IgAV nephritis（IgAVN）determines the long-term prognosis of children,and even serious complications such as end-stage renal disease occur.Although there are many studies on IgAV at home and abroad,there are still large differences in the incidence,demographic characteristics,triggering factors,and risk factors of IgAV and IgAVN in children in different regions at home and abroad.Objective This article mainly conducts a single-center retrospective study on the general clinical data,clinical characteristics and related laboratory auxiliary examinations of children with newly diagnosed IgAV.The purpose of this study is to summarize and analyze the clinical characteristics and possible risk factors of IgAV in children,and to provide more reference for clinicians to deepen the understanding and clinical diagnosis and treatment of IgAV and IgAVN in children.Methods Children with newly diagnosed IgAV who were treated in the First Affiliated Hospital of Xinxiang Medical College from June 2018 to June 2021 were collected,and the age of onset,onset season,clinical manifestations,admission and discharge time,hospital days,blood routine（WBC,N,L）were recorded.),neutrophil-to-lymphocyte ratio（NLR）,platelet-to-lymphocyte ratio（PLR）,D-dimer（D-D）,fibrinogen（Fbg）,serum creatinine（SCr）,cystatin-C（Cys-C）,uric acid（UA）,blood urea nitrogen（BUN）,stool routine,anti-streptolysin "O"（ASO）,liver function（TP,ALB,etc.）,five immune items（IgA,IgG,Ig M,C3,C4）,renal pathological results and other related auxiliary examination indicators.According to the clinical characteristics and age characteristics,the patients were divided into groups,and the differences among the above-mentioned indicators in each group were compared according to the grouping situation.The statistical software IBM SPSS 26.0 was used to analyze and organize the data,and the relevant clinical data were statistically analyzed.Results1.generally Among the 294 children included in this study,the average age of onset was 8 years old,and the peak incidence was between 4 and 10 years old,and the incidence gradually decreased with age.The highest prevalence is in autumn and winter,and the lowest in summer.The highest incidence is from October to January of the following year.2.IgAVN kidney biopsy results Among the 21 cases who completed renal biopsy,the number of patients with pathological type III was the largest;the number of clinical manifestations was proteinuria combined with hematuria;IgA deposition was found in all renal biopsy cases in immunofluorescence detection,and the number of patients with pure IgA deposition was the most.most.There was no correlation between clinical manifestation types and pathological grades.3.Analysis of systemic involvement of IgAV WBC,N%,D-D,and complement C4 in the systemic involvement group were significantly higher than those in the non-systemic involvement group,with P values ??<0.05.Binary Logistic regression analysis showed that WBC and D-D were risk factors for systemic involvement of IgAV.After ROC curve analysis,WBC and D-D had low diagnostic efficacy in diagnosing IgAV systemic involvement（0.56 years old were more likely to develop IgAV,and the age of onset in the IgAV combined with elevated ASO group was greater than that in the normal ASO group,P<0.05.There was no clear correlation between the occurrence of IgAV N and streptococcus infection in this cohort.The levels of IgA,IgG and Scr in the elevated ASO group were higher than those in the normal ASO group;the correlation analysis showed that there was a significant correlation between IgG and ASO values??（r=0.226,P<0.05）.Conclusions1.The common age of onset of IgAV is 4-10 years old,and the incidence of IgAV tends to decrease with age.There is a clear seasonal trend in the incidence of IgAV.2.WBC and D-D have low diagnostic performance in IgAV systemic involvement;the combined detection of WBC,N and NLR can significantly improve the early warning value of IgAV complicated with gastrointestinal bleeding.3.Streptococcus infection was associated with the pathogenesis of IgAV,but not with the pathogenesis of IgAVN.Streptococcus infection may cause immune dysfunction in children with IgAV.