Related Experiment Videos
Atrial natriuretic peptide in children with idiopathic hypercalciuria
P Nicolaidou1, G Nyktari, H Georgouli
11st Pediatric Department of Athens University, Greece.
Insights
Children with idiopathic hypercalciuria show lower plasma atrial natriuretic peptide (ANP) levels, particularly those with renal hypercalciuria. Renin and aldosterone levels differ between absorptive and renal hypercalciuria types.
Area of Science:
- Pediatric Nephrology
- Endocrinology
- Calcium Metabolism
Background:
- Idiopathic hypercalciuria (IH) is a common cause of pediatric kidney stones.
- Understanding the hormonal and electrolyte imbalances in IH is crucial for diagnosis and management.
Purpose of the Study:
- To investigate plasma atrial natriuretic peptide (ANP) levels in children with idiopathic hypercalciuria (IH).
- To differentiate hormonal profiles between subtypes of IH: renal hypercalciuria (RH) and absorptive hypercalciuria (AH).
Main Methods:
- Measured plasma ANP, cAMP, renin activity (PRA), serum calcium, parathyroid hormone, aldosterone, and 1,25-dihydroxyvitamin D.
- Conducted calcium loading tests to classify IH subtypes.
- Analyzed urine electrolytes and cAMP.
Main Results:
- Plasma ANP levels were significantly lower in RH patients compared to AH patients and normal controls (NC).
- Renin activity (PRA) and aldosterone levels were significantly lower in AH patients compared to RH patients and NC.
- These hormonal differences may relate to calcium balance in IH subtypes.
Conclusions:
- Lower plasma ANP in RH may be linked to calcium depletion.
- Lower PRA and aldosterone in AH might be associated with calcium excess.
- Hormonal profiles can help distinguish IH subtypes in children.
Abstract:
We measured plasma atrial natriuretic peptide (ANP) levels in 30 children with idiopathic hypercalciuria (IH) and 19 normal controls (NC). A calcium (Ca) loading test was performed in all patients to determine the type of IH. Subsequently plasma ANP, cAMP and renin activity (PRA), serum total and ionized Ca, intact parathyroid hormone, aldosterone, and 1,25-dihydroxyvitamin D as well as urine Ca, cAMP, and electrolytes were determined in all subjects. The mean (SD) plasma ANP levels were significantly lower in patients with renal hypercalciuria (RH) [21.4 (4.8) pg/ml] than in those with absorptive hypercalciuria (AH) [26.8 (7.6) pg/ml, P<0.05] and NC [27.6 (6.6) pg/ml, P<0.001]. PRA was significantly lower in AH [2.9 (1.3) ng/ml per hour] than in RH patients [7.8 (6.8) ng/ml per hour, P<0.01] and in NC [6.8 (4.6) ng/ml per hour, P<0.005]. Serum aldosterone values were significantly lower in AH [14.5 (11.4) ng/dl] than in RH patients [25.4 (14.1) ng/dl, P<0.05] and in NC [32.6 (20.5), P<0.001]. The lower plasma ANP levels in RH than in AH patients and in NC may be due to Ca depletion. The lower PRA and serum aldosterone levels in AH than in RH patients and in NC may be attributed to Ca excess.