Load Tests in Diagnostics of the Kidney Form of Primary Hyperparathyroidism in Children

After the introduction of calcium chloride (12.4 mg / kg), its blood level was examined at 20 and 120 minutes. The calcium content in children of the comparison group at 120 minutes returned to its original level, in patients with renal form (RF PHPT) its level was 1.3 times higher. The test was sensitive and made it possible to detect hypercalcemia in 39 children, in whom there was normal and hypocalcemia. Impaired renal function did not affect the significance of the sample. Under the influence of a hypertonic solution of sodium chloride, osmotic hypertension develops. Under conditions of osmotic diuresis, the elimination of calcium and sodium cations is interconnected. An increase in the level of sodium in the loops of Henley and the distal renal tubules stimulates the excretion of sodium, reducing its reabsorption, which leads to an increase in the level of calcium in daily urine in children with PHT. A sample with sodium chloride made it possible to detect hypercalciuria in 11 (21.1%) children who had normocalciuria.