Introduction: BK Polyomavirus infection has a high incidence in the post-renal transplant phase and is considered a significant cause of premature graft failure after transplantation. Pediatric renal patients undergo relatively more potent immunosuppression; however, despite the large number of studies conducted in adult renal recipients, there is limited information on BKPyV infection in the pediatric population. Objective: To estimate the incidence of BK Polyomavirus infection after kidney transplantation in pediatric patients undergoing immunosuppressive therapy at a referral center. Methodology: Observational descriptive study, with data collection based on medical records of children undergoing kidney transplantation at Hospital Ana Nery, Salvador-BA, from 2009 to 2017. Results: Forty-one children were evaluated, of which 21 (51.2%) were female. The mean age of the sample was 11 ± 3, with a higher frequency of patients in the age range of 13-17 years (43.9%). Regarding the presence of BKPyV infection, most patients were not infected (56.1%). Regarding the type of antiproliferative and calcineurin inhibitor, Mycophenolate Mofetil was used in 37 (90.2%) patients and Tacrolimus in 40 (97.6%). When comparing the groups with the presence or absence of BKPyV infection, there was no statistically significant difference between the variables: sex (p = 0.890), age (p = 0.829) and type of antiproliferative used (p = 0.187). In the analysis of renal function, an increase in creatinine was observed in 38.9% of infected patients, while among the uninfected, only 13% presented an increase in the period of one year. The difference between these two groups (p = 0.05) therefore demonstrated an association between worsening renal function and the presence of BKPyV infection. Conclusion: The incidence of BK Polyomavirus infection in pediatric patients undergoing kidney transplantation, in the period of one year after the surgical procedure, is almost 50%. No differences could be demonstrated between the groups with and without BKPyV infection and established risk factors, such as sex, age and immunosuppressive therapy used. Furthermore, a worsening of renal function was evidenced among infected patients.

The authors have declared no competing interest.

This study did not receive any funding

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