[The effect of decreasing serum calcium in serum during hemodialysis on PTH levels in children with end stage renal disease].

The aim of our study was to evaluate serum Ca and PTH intact levels in children during one hemodialysis session using a low calcium level dialysate (1.25 mEq/l). The study was performed in 6 children with end-stage renal disease. We analysed the parameters of calcium-phosphorus metabolism in children 18 months before the test. In 5 of children the increase of PTH level during hemodialysis was lower than in healthy people. In 3 patients with hyperparathyroidism the basal PTH (PTHb) level before the test was high and increased by 45%, 67% and 118% during hypocalcemic stimulation. In 2 patients suppression of parathyroid function was diagnosed due to low serum PTHb level and small increase during hypocalcemic stimulation. Despite low basal PTH level, one of the patients respond to hypocalcemic stimulation like healthy subjects. Dynamic monitoring of the PTH level during hypocalcemic stimulation is a very useful method of estimation parathyroid gland function and adjusting doses of vitamin D metabolites.