Correction of Zinc Deficiency in Children With Chronic Kidney Disease and Kidney Transplant
Status:
Completed
Trial end date:
2017-01-01
Target enrollment:
Participant gender:
Summary
Children with chronic kidney disease, even after transplantation, may be at risk for bone
problems due to an imbalance of calcium and phosphorus in the blood, especially as their
kidneys progressively fail to function. While some drug and diet treatments are available to
prevent such bone disease, many children refuse to take them due to bad taste and tummy
cramps. If calcium and phosphorus status remain abnormal for a long time, hard crystals can
form in the blood vessels, eventually clogging them and resulting in heart problems.
Investigators are studying possible new methods to help the kidneys maintain a normal balance
of nutrients in the blood which is important for growing healthy bones and the prevention of
side effects in blood vessels that can lead to heart disease. One method is to improve the
team work of a hormone FGF-23 and a protein called Klotho that together stimulate the kidneys
to increase phosphate removal. Investigators propose that this problem may be due to low
blood zinc levels which often occur in children with kidney disease. Thus, in this study,
investigators propose to first measure zinc in blood from children with chronic kidney
disease (CKD) or who have had kidney transplants to assess zinc and phosphate status, the
hormone FGF-23 and its assistant Klotho. If zinc status is low, the children will receive
zinc supplementation for 3 months. After treatment with zinc, the same blood measurements
will be repeated to determine if the zinc supplements have helped the hormones to remove
phosphate from the body. If this pilot project is successful, investigators will then
consider a larger scale project involving adult patients as well as pediatric patients from
other pediatric centers. This project will also guide investigators as to whether they need
to introduce zinc measurements as part of routine testing of CKD and transplant patients. In
addition to measuring zinc levels in study participants, trace elements (TE) will also be
measured. These include heavy metals such as cadmium, chromium, nickel, vanadium, copper,
lead, manganese and selenium. Very little is known about levels and metabolism of TE in CKD
especially before dialysis. In adults, cadmium, chromium, nickel, and vanadium probably
accumulate in hemodialysis patients, while copper and lead may accumulate. Manganese,
selenium are probably deficient. The study will allow investigators to obtain the information
about TE in this group of pediatric patients.