| ObjectiveTo analyze the incidence of BK virus positive and BK virus negative in children after renal transplantation.Compare the difference of serum creatinine level between BK virus positive group and BK virus negative group at 1 month and 1 year after operation.To compare the incidence of BK virus infection in children with different age groups and different concentrations of tacrolimus valley.To explore the risk factors of BK virus infection in children after renal transplantation and establish a prediction model of BK virus infection in children after renal transplantation.MethodsThe clinical data of children with chronic renal failure who underwent renal transplantation from 2013 to 2020 in the Department of Renal Transplantation,First Affiliated Hospital of Zhengzhou University were retrospectively analyzed.According to the detection results of blood and urine BK virus DNA load,children were divided into urine BK DNA(+),blood BK DNA(-)or blood BK DNA(+)positive group,that is,BK virus positive group.Urine BK DNA and blood BK DNA were negative,namely BK virus negative group,and the follow-up time was 2-5years.To analyze the incidence of BK virus infection in children with different ages and different concentrations of tacrolimus valley after stratified renal transplantation.The related factors affecting BK virus infection were analyzed statistically: donor sex,donor donation type,donor kidney cold ischemia time,recipient age,sex,weight,dialysis type,pre-transplant albumin,pre-transplant lymphocyte count,immune induction program,immunosuppressant maintenance program,delayed graft function,DGF),acute rejection,tacrolimus valley concentration,mycophenolic acid valley concentration,etc.Application of ROC curve to establish a prediction model of BK virus infection in children after renal transplantation.ResultsAccording to the inclusion criteria and exclusion criteria,a total of 197 children renal transplant recipients were included in this study,including 61 cases(31.1%)in BK virus positive group and 136 cases(68.9%)in BK virus negative group,with an average age of(12.2 3.7)years,with a male-female ratio of 137/60.In the BK virus positive group,the incidence of BK virus infection was 73.7% one year after operation and 26.3% one to five years after operation.The peak period of BK virus infection in children after renal transplantation is 1 year after operation,and then the incidence of BK virus decreases obviously.One year after transplantation,the blood BK DNA(+),urine BK DNA(+),urine BK DNA and blood BK DNA were all negative,and one month after operation,the serum creatinine levels of the three groups increased from(89.7 16.4 umol/l)to(196.6 28.6 umol/l)and(81.3 15.7 umol)respectively.At one year after the operation,the serum creatinine level was significantly higher than that of viral urine disease(196.6 28.6 umol/LVS 122.4 21.7umol/L,P=0.000)and BK virus negative group(196.6 28.6 umol/L vs 87.9 19.7umol/L,P=0.000).Univariate risk factors analysis of BK virus infection found that cold ischemia time of donor kidney,hemodialysis status and lymphocyte count before transplantation were the risk factors of BK virus infection in children after renal transplantation(P < 0.05).Multivariate analysis showed that lymphocyte count and cold ischemia time were high risk factors for BK virus infection(P = 0.004;P=0.000)。According to the age of 5,9 and 12 years old,the different age groups were stratified,and the P values of each age group were 0.041,0.300 and 0.523,respectively.With tacrolimus valley concentration > 8ng/L,the P value was 0.436 when stratified analysis was carried out.The area under the curve(AUC)of cold time and lymphocyte count level in diagnosis of BK virus infection were 0.560 and 0.581,respectively.95%CI 0.479-0.640,0.489-0.673。The prediction model including cold ischemia time and lymphocyte count level has AUC of 0.621 and 95% CI of0.539-0.702.ConclusionThe results of our research show that the risk factors of BK virus DNA positivity after kidney transplantation are the age of recipients younger than 5 years old,low lymphocyte count before transplantation,hemodialysis state and long cold ischemia time.Strengthening the detection of BK virus after kidney transplantation and giving early intervention to such recipients may be an effective way to prevent BK virus-related nephropathy. |
