Renal injury in children with a congenital solitary kidney – a single center experience

Abstract

Introduction/Objective Reduced kidney length, low birth weight, obesity, and ipsilateral congenital anomalies of the kidney and urinary tract (CAKUT) are risk factors for renal injury (hypertension, proteinuria, and chronic kidney disease) in single-functioning kidneys. Our study aimed to investigate the risk factors for renal injury and outcome in children with congenital solitary kidney (CSK).

Methods We collected data from the medical records of 95 children with CSK.

Results Children with CSK were predominantly male (61%). An abnormal ultrasound (US) view of a solitary kidney was found in nine (9%) and renal length below the 75th percentile in eight (11%) children. Seven (7%) children had low birth weight, 18 (20%) were obese, 26 (28%) had urinary tract infections, 24 (25%) had CAKUT and 28 (29%) were treated with an angiotensin-converting enzyme (ACE) inhibitor. Decreased glomerular filtration rate was found in three, proteinuria in 14 (15%), and arterial hypertension in 10 (11%) children. A total of 23 (24%) children met the criteria for renal injury. In multiple logistic regression, only US abnormalities approached significance (OR 5.6, p = 0.08). Compared to other studies, we had a higher percentage of an ACE inhibitor prescribed for renal protection. This could be the reason for the low percentage of renal injuries in our study.

Conclusion Monitoring blood pressure, proteinuria, and renal function might be of utmost importance, especially in children with CSK and abnormal US appearance. Additionally, further studies are needed to confirm the possible beneficial effect of renoprotective treatment in patients with CSK.

Keywords: solitary kidney; renal injury; renoprotective treatment; ACE inhibitor; children; abnormal ultrasound appearance