Plasma Calcium Fractions in Normal Subjects From Birth to Adult Ages

Abstract

Summary A simple and rapid method to determine ultra‐filtrable calcium in plasma is described in detail. Total calcium, ultrafiltrable calcium (Cauf), and protein‐bound calcium in plasma are reported for 202 normal children (range 0–16 years of age) divided into 12 age groups, as well as for 93 healthy male blood donors. There was a decrease in plasma calcium and ultrafiltrable calcium after 1–21 hours of life. The minimum value was reached at 24–48 hours of life. An increase was then seen during the first week of life. Later in childhood total calcium and Cauf decreased continuously and significantly with age, and with the most marked rate during the first two‐three years. The ultrafiltrable calcium fraction was found to be responsible for the changes in total plasma calcium. In 24–48 hours of life and 5–7 days of life protein‐bound calcium was significantly lower as well. There were no significant differences between males and females in childhood.

Calcitonin and Parathyroid Hormone – Relation to Early Neonatal Hypocalcemia in Infants of Diabetic Mothers

“…The analytic methods used were the following: ultrafiltrable calcium was determined by the method of Bergman and Isaksson [5], total calcium was determined by flame photometry (Eppendorf), calcium in the urine was determined by EDTA-titration. phosphorus in plasma and urine by the method of Fiske-Subbarow and total protein by the Biuret reaction.…”

Plasma Calcium Fractions during the First Days of Life with Special Reference to Neonatal Hypocalcaemia

“…Urine was collected between the blood samples. The analytical methods used were the following: ultrafiltrable calcium was determined ac cording to Bergman and Isaksson [4], The method is based on ultrafiltration through a collodion membrane with overpressure and simultaneous pH and temperature controls. 1.5-2.0 ml plasma is needed and the ultrafiltration procedure takes 10-15 min.…”