Urinary biomarkers indicate pediatric renal injury among rural farming communities in Sri Lanka

Pediatric renal injury is an emerging health concern in communities affected by chronic kidney disease of uncertain etiology (CKDu). Early detection of susceptibilities through highly sensitive and specific biomarkers can lead to effective therapeutic and preventive interventions against renal diseases. Here, we aimed to investigate the utility of kidney injury molecule (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) in early detection of renal abnormalities in selected pediatric communities in Sri Lanka. The study areas were stratified as CKDu endemic, emerging, and non-endemic based on the prevalence of CKDu, and a total of 804 school students (10–18 years of age) participated in the study. The median (IQR) urinary KIM-1 levels of the participants were 0.193 (0.026–0.338), 0.082 (0.001–0.220) and 0.040 (0.003–0.242) ng/mgCr for CKDu endemic, emerging and non-endemic regions respectively. Participants from CKDu endemic regions reported elevated (p < 0.0001) urinary KIM-1 expression compared to those from the other regions. The median (IQR) NGAL levels in participants from CKDu endemic (2.969; 1.833–5.641), emerging (3.374; 1.766–6.103), and non-endemic (3.345; 1.742–5.128 ng/mgCr) regions showed no significant difference. Also, urinary albumin-creatinine ratio (UACR) showed no significant differences across gender or residency. The prevalence of albuminuria was 1–2% in the locations irrespective of CKDu burden. Albuminuric participants reported higher (p < 0.05) urinary KIM-1 levels in comparison to normoalbuminuric participants. Significantly elevated urinary KIM-1 expression in a pediatric population from CKDu affected regions, especially in the presence of albuminuria, may indicate low-grade early renal damage supporting the utility of KIM-1 as a quantifiable biomarker.