Introduction:
Bacteriuria is common in kidney transplant recipients (KTR) and it may affect graft survival.

Objective:
To describe the incidence, clinical manifestations and microbial susceptibility of the symptomatic (SB) and asymptomatic (AB) bacteriuria in KTR, and to define the initial empirical treatment.

Methods:
Retrospective cohort study of all KTR<18 years with bacteriuria that were transplanted between January 2006 and December 2016. Clinical, demographic, laboratory characteristics and follow-up time were investigated. Bacteriuria was classified as either SB or AB. Statistical analysis was performed using Excel 2010 program.

Results:
20 kidney transplants were performed. The female/male ratio was approximately 2:1 and 45% of the patients had bacteriuria. Of the 55 bacteriuria episodes, 20 were symptomatic and 35 asymptomatic. The mean age of the patients was 10.7±4.7 years. The more frequent primary renal diseases were neurogenic bladder (44.4%), renal dysplasia (22.2%), nephronophthisis, vesicoureteral reflux and obstructive uropathy (11.1% each). The median number of episodes/patient was 3.9. The mean time to post-transplant presentation was &lt;6 months in 25% of the cases, 6-12 months in 20% and &gt;12 months in 54.5%. The median time between the transplantation and the first AB episode was 3 months, and between the first SB episode was 7 months. The symptoms found in patients with SB included fever (80%), hematuria (15%) and septic shock (5%). No patient died due to urinary tract infections (UTI), but 33.3% of the patients with bacteriuria required admission to intensive care units. The most frequent bacteria isolated was Escherichia coli (E.coli) (54.5%). Extended‐spectrum beta‐lactamase (ESBL) producing bacteria was found in 20% of the isolates. When comparing SB and AB, E.coli was associated with SB (p=0.047 OR:1-9.9). All SB cases were verified in patients with neurogenic bladder (p=0.013).

Conclusion:
The recognition of high incidence of ESBL producing bacteria- related to UTI in (children) KTR may be very important for decision on the use of antibiotics during post- transplantation period. In this case, the use of carbapenem and ciprofloxacin should be recommended as initial empiric treatment.