Subclinical Markers of Kidney Injury in Children with Congenital Solitary Kidney

Abstract

Objective: Congenital solitary kidney (CSK) is generally associated with preserved renal function during childhood; however, early subclinical markers of renal injury may already be present. This study aimed to evaluate renal function, microalbuminuria, office blood pressure (OBP), and ambulatory blood pressure monitoring (ABPM) findings in children with CSK compared with healthy controls. Methods: Thirty-nine children aged 5–18 years with CSK (25 with unilateral renal agenesis and 14 with multicystic dysplastic kidney) and 30 healthy age- and sex-matched children were enrolled. Renal function, 24-hour urinary microalbumin excretion, OBP, and ABPM parameters were evaluated and compared between the groups. Results: Renal function parameters remained within the normal range and did not differ significantly between the groups. Twenty-four-hour urinary microalbumin excretion was significantly higher in children with CSK than in controls (18.2 ± 7.2 vs. 8.2 ± 4.7 mg/day, p=0.033). The prevalence of abnormal blood pressure was also significantly higher in the CSK group than in controls (p=0.024). Conclusion: Children with congenital solitary kidney may exhibit early markers of subclinical renal injury despite preserved renal function. These findings support careful longitudinal follow-up to identify children who may be at increased risk of future renal and cardiovascular complications.