Lab Tests

Below is a list of the most common blood tests that doctors use to find out how well the kidneys work. The Children’s Kidney Transplant team will check these lab tests during your child’s pre-transplant evaluation and during and after his kidney transplant.

Blood Test


Change with Kidney Disease



Albumin is a protein in the blood that is made by the liver. It transports certain substances in the blood and also helps maintain normal pressure inside the blood vessels. Kidney disease causes albumin to be lost in the urine.




BUN (blood urea nitrogen)

As kidneys break down protein, a substance called urea is formed. Urea is a waste product that is normally removed from the body in the urine. Poor kidney function will cause levels to rise.





Creatinine is made as the body uses muscle and energy. It is removed from the body by the kidneys. Poor kidney function causes creatinine levels to rise.





Potassium is salt found in the cells in the body and in the blood. It is needed for nerve and muscle function. Excess potassium is excreted in the urine. Poor kidney function causes potassium levels to rise.





Hemoglobin carries oxygen to the body in red blood cells. Hemoglobin is low when iron in the blood is low, which happens with kidney failure. This is called anemia.





Hematocrit measures the number of red blood cells in the blood. A low hematocrit level can show anemia or blood loss.





This is a test to measure the sugar level in the blood.