URINARY-EXCRETION OF CATECHOLAMINES IN HOSPITALIZED AND NONHOSPITALIZED HEALTHY-CHILDREN AND ADOLESCENTS

Non-conjugated catecholamines were measured in morning urine samples f rom 111 healthy, non-hospitalized subjects aged 8-18 y and in 16 hospi talized, healthy subjects aged 12-16 y. The catecholamines were extrac ted by cation exchange columns and alumina adsorption and quantitated with HPLC with electrochemical detection. The concentration of catecho lamines was related both to the urinary creatinine concentration and t o the collecting period and body surface area. Linear regression analy sis was used to estimate continuous age-related reference centiles bas ed upon the measurements from the 111 non-hospitalized subjects. The u pper limits for the adrenaline/creatinine and noradrenaline/creatinine ratios were lower than in previous studies. The excretion of adrenali ne and noradrenaline per hour and m(2) body surface area was higher in the 16 hospitalized than in the 74 age-matched non-hospitalized subje cts. The excretion of the catecholamines expressed per hour and m(2) b ody surface area and expressed relative to creatinine excretion, decre ased with increasing age, and the excretion of adrenaline and noradren aline per hour and m(2) body surface area was higher in boys than in g irls. In conclusion, standardization of urine sampling leads to more n arrow ranges for urinary adrenaline and noradrenaline excretion in hea lthy children and adolescents.