PURPOSE: There are many methods for the evaluation of the renal function. The proximal tubule of the nephrons have a role of reabsorption of the materials such as water, electrolytes, glucose, amino acids, and small molecular weight protein through the glomerular filtration. Therefore if abnormality is in the proximal tubule, these materials can be changed both in serum & urine. It is very useful to know the normal value of the materials for the age related concentration in serum & urine. METHODS: A study of age related serum & urine calcium, phosphorus, uric acid concentration & Ca/Cr ratio, Cua/Ccr ratio & TRP(tubular reabsorption of phophorus) levels was carried on 178 prematures, neonates, infants & children who were admitted to hallym university hospital from Jul. 1994 through Jan. 1995. RESULTS: The results obtained were as follows, 1)The mean serum calcium levels were the premature 9.8+/-1.3mg/dl, neonate 9.1+/- 1.3mg/dl, 2-12mo 9.8+/-1.2mg/dl, 13-24mo 9.8+/-0.9mg/dl, 25mo-5yr 9.1+/-1.4mg/dl, and 6-15yr 9.2+/-0.8mg/dl. 2)The mean urine calcium levels were the premature 1.0+/-0.8mg/dl, neonate 1.0+/-0.8mg/dl, 2-12mo 2.7+/-1.7mg/dl, 13-24mo 3.0+/-2.2mg/dl, 25mo-5yr 4.1+/-1.9mg/dl, and 6-15yr 4.5+/-2.9mg/dl. 3)The mean serum phosphorus levels were the premature 6.7+/-1.6mg/dl, neonate 6.0 +/-1.3mg/dl, 2-12mo 5.5+/-0.7mg/dl, 13-24mo 5.0+/-0.7mg/dl, 25mo-5yr 4.5+/-0.8mg/dl, and 6-15yr 4.5+/-0.6mg/dl. 4)The mean urine calcium levels were the premature 9.1+/-6.4mg/dl, neonate 10.5+/-7.9mg/dl, 2-12mo 25.9+/-11.2mg/dl, 13-24mo 26.1+/-12.6mg/dl, 25mo-5yr 24.4+/-13.7mg/dl, and 6-15yr 20.3+/-10.7mg/dl. 5)The mean serum uric acid levels were the premature 6.0+/-3.1 mg/dl, neonate 4.7+/-1.4mg/dl, 2-12mo 4.6+/-1.6mg/dl, 13-24mo 4.7+/-1.9mg/dl, 25mo-5yr 4.5+/-1.2mg/dl, and 6-15yr 4.2+/-1.6mg/dl. 6)The mean urine uric acid levels were the premature 27.2+/-18.1mg/dl, neonate 24.3+/-12.8mg/dl, 2-12mo 27.1+/-15.8mg/dl, 13-24mo 27.5+/-14.5mg/dl, 25mo-5yr 28.8+/-14.1 mg/dl, and 6-15yr 26.1+/-9.2mg/dl. 7)The mean levels of the 24hours urine Ca/Cr ratio were the premature 0.1+/-0.08, neonate 0.12+/-0.1, 2-12mo 0.2+/-0.1, 13-24mo 0.2+/-0.1, 25mo-5yr 0.2+/-0.1, and 6-15yr 0.14+/-0.07. 8)The mean levels of the Cua/Ccr(Fractional urate excretion) ratio were premature 83.2+/-115.3%, neonate 19.3+/-41.5%, 2-12mo 19.8+/-9.4%, 13-24mo 19.3+/-13.4%, 25mo-5yr 15.7+/-5.5%, and 6-15yr 16.1+/-4.9%. 9)The mean level of the TRP ratio were premature 88.3+/-8.2%, neonate 111.7+/-129.4%, 2-12mo 84.5+/-8.9%, 13-24mo 85.0+/-9.9%, 25mo-5yrs 86.9+/-7.5, 6-15yrs 89.1+/-6.4%. CONCLUSIONS: This study was performed to understand the develpoment renal function.
Amino Acids ; Calcium ; Child ; Electrolytes ; Filtration ; Glucose ; Humans ; Infant ; Infant, Newborn ; Molecular Weight ; Nephrons ; Phosphorus* ; Reference Values ; Uric Acid*