High prevalence of febrile urinary tract infections after paediatric renal transplantation.

Background: Adult data suggest that urinary tract infections occur frequently after renal transplantation (RTx) and contribute to mortality and graft loss; data in children are limited. Therefore, we evaluated prevalence, short and long-term morbidity and confounding factors of febrile UTI (fUTI) after paediatric RTx.

Methods: In a retrospective cross-sectional study of three centres, we analysed data on 110 children followed for 4.9+/-3.4 years after successful transplantation.

Results: 40/110 (36%) patients had at least one fUTI at a median time of 0.98 years (range 0.02-8.96) after RTx; 11 patients (28%) had recurrent fUTI. Serum creatinine (SCr) rose significantly from 1.15+/-1.13 to 1.83+/-1.69 mg/dl, (P<0.001) during the fUTI, declining to baseline values after treatment. At the last followed-up calculated mean, GFR was comparable between fUTI and non-fUTI groups (75+/-26 vs 71+/-22 ml/min/1.73 m2). During fUTI mean, C-reactive protein (CRP) increased to 123+/-75 mg/l. Febrile UTI were significantly more frequent in girls compared to boys (22/44 vs 18/66, P<0.05) but occurred significantly earlier in boys than in girls [median 0.63 (range 0.02-4.15) vs 1.07 (0.04-8.96) years after RTx; P<0.02]. Also, patients with urinary tract malformations (UTMs) and neurogenic bladder as underlying diagnosis and those with urological surgery prior to transplantation had an increased risk for fUTI.

Conclusion: fUTI is a frequent complication with significant short-term morbidity especially in girls and children with UTMs, neurogenic bladder and those with urological surgery. Long-term follow-up and prospective studies confirming specific risk factors, preventive measures and impact on graft survival are necessary.