[Age dependence of kidney function].
Although kidney function is immature in infants and decreases with increasing age in adults, when assessing the kidney clearance, it is not common to make an adjustment for age. On the other hand, correction for the standard body surface is generally accepted. Previous studies have yielded contradictory results, probably due to the small numbers of patients studied. To obtain the statistically significant relationship between age and kidney clearance, we compiled more than 1000 studies. These studies were divided into three groups: (1) children under 2 years of age (n = 71); (2) children and adolescents from 2 to 15 years (n = 64 male/58 female); (3) adults (n = 474 male/424 female; age: 16-80 years). Total clearance determinations were only considered if there were no differences between the two kidneys and if there was no obstruction of micturition or other pathological findings. Surprisingly, the statistical analysis showed no differences in clearance values between sexes. The maximal clearance values were found in the groups with children about 8 years old and the greatest scatter of values was seen in children under 2 years of age (a discrepancy between maturation age and calendar age). The complete set of data was based on the presumption that continuous function consisting of three trunks describes the course of normal kidney clearance in relation to patient age. If one determines an arbitrary reference value (e.g., 25 years), correction factors can easily be derived from the function described in order to compare individual clearance with a normal value.(ABSTRACT TRUNCATED AT 250 WORDS)
Steinsträsser
A
A
Abteilung für Nuklearmedizin Radiologischen Universitätsklinik, Hamburg/Saar.
Berberich
R
R
Wilhelm
H
H
Curschmann
J
J
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007465:Iodohippuric Acid; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D012016:Reference Values
D007465:Iodohippuric Acid
Altersabhängigkeit der Nierenfunktion.