Post-transplant infection-related hospitalisations have increased over time in children after renal transplantation. We attempt to describe those hospitalisations in a cohort of paediatric renal transplant recipients, to study the risk factors of infections and to evaluate the additional cost of those hospitalisations.

Patients under 20 years receiving a kidney transplant in France between 2008 and 2013 were screened from the National medico-administrative Hospital Discharge database and a probabilistic matching was performed with the National Renal Transplant Database. Costs’ calculation was based on the Public Health Care Tariff. We used Cox regression to study the risk factors of hospitalisation. To assess the evolution of the risk with time, we calculated the instantaneous risk of hospitalisation per month for all infections and by type of infection.

Among 593 patients, 660 hospitalisations in 260 patients were identified; median follow-up time was 34.7 [14.7–53.2] months. The first cause of hospitalisation was UTI, incidence rate of 16.6 per 100 patient–years (py) followed by viral infections (15.6/100 py) including 128 digestive infections, 70 respiratory tract infections and 47 hospitalizations related to herpes viruses. Risk factors of hospitalisation were a younger age [HR 0.95 (0.92–0.97) per year], HLA mismatches [HR 1.14 (1.01–1.28) per mismatch] and the use of Cyclosporine rather than tacrolimus [HR 0.72 (0.54–0.95)]. Female gender, uropathy and cold ischemia time were specific risk factors of UTI. Instantaneous risk of infection decreased with time but CMV infection displayed a peak at the end of the prophylaxis. Total cost of infection-related hospitalisations was 1600k € (933 €/py) for 3529 days of hospitalisation.

This study points out the high burden of infection in paediatric transplanted patients, especially the youngest ones in terms of quality of life and health cost and highlights possible ways of improvement for clinical practice.