Angiotensin Peptide Levels in Children With Predialysis Chronic Kidney Disease

BACKGROUND: The changes in local renin-angiotensin system (RAS), independent of systemic RAS, are suggested to play a role in the pathophysiology of chronic kidney disease (CKD). This study aimed to investigate RAS molecules in children with predialysis CKD and to evaluate their relationship with echocardiographic parameters. METHODS: The patients with predialysis CKD (n = 37) and control group (n = 48) were included. Angiotensin-A, angiotensin-2, angiotensin converting enzyme (ACE)-1, ACE-2, angiotensin 1-7 and alamandin levels were determined by ELISA. Echocardiography was performed with M-mode, pulsed wave Doppler, tissue Doppler, and speckle tracking strain. RESULTS: Serum angiotensin peptide levels were similar between patients and controls. Urinary angiotensin peptides were lower in patients and were positively correlated with glomerular filtration rate (p < 0.001 for each). Urinary angiotensin peptides were lower and serum angiotensin-2 and angiotensin 1-7 were higher in patients without hypertension compared to controls (p < 0.05). Serum ACE-2 was lower in patients with hypertension (p < 0.05). Urinary angiotensin peptides and serum angiotensin-A were lower in CKD with hypertension compared to healthy children (p < 0.05). In logistic regression analysis, hypertension was negatively correlated with urinary angiotensin peptides. Serum angiotensin-A was negatively and angiotensin-2 was positively correlated with hypertension (p < 0.05). Mitral lateral E was positively correlated with serum alamandin and ACE-2 (p < 0.05). Tricuspid E/A correlated with serum alamandin, angiotensin-A, ACE-1 and ACE-2 levels (p < 0.05). Tricuspid lateral S was negatively correlated with urinary alamandin and urinary angiotensin-A (p < 0.05). CONCLUSION: Circulating and local RAS molecules may play a role in renal dysfunction, hypertension, and echocardiographic alteration in children with predialysis CKD.