The Analysis Of Risk Factors On Relapse Of Antineutrophil Cytoplasmic Antibody–Associated Vasculitis At The Stage Of Chronic Renal Failure

Objectives: With the modern immunosuppressive therapy,survival rate of patients with AAV has signifcantly improved The majority,85–95 % patients could achieve complete clinical remission.However,30–55 % patients would relapse recurrently even after remission.We have observed that some AAV patients at the stage of chronic renal failure showed multiple relapses.In this study we explored ris k factors for the relapse of ANCA associated vasculitis at the stage of chronic renal failure.Methods: We selected 25 patients with AAV at the stage of chronic renal failure.In all patients,AAV was diagnosed at the Renal Division of Qingdao University Affiliated Hospital from August 2012 to December 2016,and all patients met the Chapel Hill Consensus Conference nomenclature for AAV.Serum CRP,ESR,serum creatinine,serum ANCA,white blood cells,platelets,hemoglobin,serum albumin,and system involvements,eGFR,BVAS scores,were included for analysis.Urine red blood cell counts and proteinuria in a 24 hours urine collection in patients with urine were also included in the analysis.The value of various clinical parameters for relapse was analyzed.Statistical analysis was performed using SPSS version 19.0.Data were showed as mean ± standard deviation or median and quartiles,according to their distribution.Comparison was performed using the LSD-t test or the non-parametric test(Mann-Whitney U test).Categorical variables are presented as percentages and comparison test were performed using Pearson χ2 test or Fisher’s exact test.Correlation analysis of categorical variables were performed using Spearman correlation analysis.Models of logistic binomi al regression were built using relapse(yes or no)as dependent variable.A P<0.05 was considered as statistically significance.Results:(1)The patient group comprised 12(48%)men and 13(52%)women aged 65.56±12.01 years.Relapse occurred in 15(60%)of 25 patients with AAV at the stage of chronic renal failure.The average age was 66.67±12.32.10 patients continued remission.The average age was 63.90±12.00.(2)There was no significant difference in laboratory tests such as CRP,ESR,serum creatinine,serum ANCA type,white blood cells,platelets,hemoglobin,serum albumin and eGFR,BVAS scores at the time of initial diagnosis between relapsed and non-recurrent patients.In the relapse group,the lung involvement caused by AAV was significantly higher than that in the non-relapse group(12 VS 3,P=0.034).The urine red blood cell count in the recurrent urine group was significantly higher than that in the non-recurrence group(98.48(63.38-238.95)VS 20.59(3.75-124.94))(P=0.04).Proteinuria in a 24 hours urine collection was found no statistical difference.(3)During the follow-up period,relapsed group and non-relapsed group had significant differences in laboratory tests such as CRP,ESR,urine red blood cell count,and BVAS score.There was no significant difference in serum creatinine levels,serum ANCA types,white blood cell,platelet,hemoglobin,and serum albumin.In the relapse group,the lung involvement caused by AAV was significantly higher than that in the non-relapse group(32 VS 3,P=0.011).Thirty-three cases in the relapse group had an infection before recurrence,and mainly pulmonary infection(90.9%);the non-recurrent group had 1 cases,and the difference was statistically significant(P).Urine red blood cell counts in patients with urine in the recurrent group were significantly higher than those in the non-recurrent group(100.10(18.20-246.00)VS.32.6(1.50-123.55)),and the difference was statistically significant.Proteinuria in a 24 hours urine collection was not statistically different.(4)Uni-variable test revealed that possible risk factors were infection(P<0.001)and lung involvement caused by AAV(P=0.034).By Logistic multiple factors re gression analysis,the risk factor selected was only infection(P=0.005,OR=25.237,95% CI: 2.631-242.098).Conclusions: Pulmonary infection was found to be the independent risk facor for the relapse of AAV at the stage of chronic renal failure.Pulmonary involvement caused by AAV is a suspected cause of clinical relapse in AAV patients with chronic renal failure.The urine red blood cell check is a sensitive maker for AAV activity even in patients with chronic renal failure.The presence of hematuria is a si gnificant indicator of future relapse.Urinary chronic renal failure patients need to be tested regularly.