Risk factors of cytomegalovirus infection and the predictive value of mannose-binding lectin after renal transplantation

Objective To investigate the risk factors of cytomegalovirus(CMV) infection in renal transplant recipients and the predictive value of natural immune molecules mannose-binding lectin (MBL) on CMV infection after renal transplantation. Methods Eighty-three recipients who underwent renal transplantation in Affiliated Shandong Province Qianfoshan Hospital of Shandong University from January 2010 to June 2011 were selected as research subjects. This study was approved by local ethical committee and the informed consent of all participating subjects was obtained.All of the recipients were followed up at least 6 months.During the follow-up period, copies of CMV deoxyribonucleic acid(DNA) in blood and urine were detected by fluorescence quantitative polymerase chain reaction(FQ-PCR). Patients were diagnosed as CMV infection when CMV DNA was over 103 copies/ml in blood or concentrated urine.Eighty-three recipients were divided into CMV infection group and non CMV infection group.The levels of pre-operative serum MBL of renal transplant recipients were detected by enzyme-linked immune absorbent assay (ELISA) and compared in two groups.One-way analysis was used in 6 factors which might affect CMV infection.Logistic multi-factor regression analysis was then used in significant factors of one-way analysis.And the independent risk factors were selected. Results During the follow-up period of 6 months, 18 recipients (22%) developed CMV infection(CMV infection group), and 65 recipients didn't develop CMV infection(non CMV infection group). The levels of serum MBL of recipients in CMV infection group before transplantation were significantly lower than those in non CMV infection group(P0.01). After the therapy of ganciclovir, the copies of CMV decreased to negative in 18 recipients with CMV infection. No CMV pneumonia or graft dysfunction occurred.The result of one-way analysis showed that the risk factors of CMV infection included CMV serology positive of donors/negative of recipients(D+/R-) before transplantation, MBL500 ng/ml, application of antithymocyte globulin and occurrence of rejection after transplantation(P=0.018,0.001,0.011,0.005, respectively).The result of Logistic multi-factor regression analysis showed that the independent risk factor of CMV infection included the level of pre-operative MBL 500 ng/ml before renal transplantation(odds ratio 5.691, 95% confidence interval 1.746-18.548, P=0.004) and CMV serology positive of donors/negative of recipients(D+/R-)(odds ratio 7.673, 95% confidence interval 1.107-53.178, P=0.039). Conclusions The level of pre-operative MBL(500 ng/ml) and CMV serology positive of donors/negative of recipients(D+/R-) before transplantation are the independent risk factors of CMV infection after renal transplantation.The level of serum MBL of recipients before transplantation can predict the occurrence of CMV infection after renal transplantation. If the level of serum MBL is detected lower than 500 ng/ml before renal transplantation, prophylaxis of virus infection should be applied before the operation.In pairing between donors and recipients, it should be avoided to transplant kidney from CMV serology positive donors to negative recipients.