Evolution of blood pressure in children with congenital and acquired solitary functioning kidney

BACKGROUND It is not yet clear if blood pressure and renal function changes evolve differently in children with a congenital or acquired solitary functioning kidney. This study aims to assess if there are any differences between these two types of solitary kidney patients. METHODS Current research is a retrospective study assessing the evolution of glomerular filtration rate, proteinuria, and blood pressure in clinical records of 55 children with a solitary functioning kidney (37 congenital and 18 acquired). We used the medical records of children who had been assisted, in our unit of pediatric nephrology, for a period of 14 years (168 months), from the time of diagnosis, between January/1997 and December/2015. RESULTS During the study period, glomerular filtration rate (T0 128.89 ± 32.24 vs T14 118.51 ± 34.45 ml/min/1.73 m2, p NS) and proteinuria (T0 85.14 ± 83.13 vs T14 159.03 ± 234.66 mg/m2/die, p NS) demonstrated no significant change. However, after 14 years of follow-up 76.4% of patients had increased levels of arterial hypertension with values over the 90th percentile for gender, age, and height. Specifically, children with an acquired solitary functioning kidney mainly developed hypertension [T0 2/17 (12%) vs T14 9/17 (52.9%) p < 0.025], whereas children with a congenital solitary functioning kidney mainly developed pre-hypertension [T0 3/38 (7.9%) vs T14 17/38 (44.7%) p < 0.0005]. CONCLUSIONS The renal function of children with solitary functioning kidneys remains stable during a follow-up of 14 years. However, these children should be carefully monitored for their tendency to develop arterial blood pressure greater than the 90th percentile for gender, age, and height.