DDAVP test for estimation of renal concentrating capacity in infants and children.

A new method for the estimation of the renal capacity to concentrate urine is described. Intranasal administration of DDAVP (1-deamino-8-D-arginine vasopressin), a synthetic analogue of the antidiuretic hormone, has been used for the measurement of urine concentrating performance in 79 children and 25 infants. By comparative studies of different doses of intravenous and intranasal administration of DDAVP, a standard procedure has been elaborated with the intranasal administration of 20 μg in children and 10 μg in infants. The maximum urine osmolality values obtained with the DDAVP test are compared to those achieved with other renal concentration tests, i.e. dehydration test and pitressin test. The present investigation shows that intranasal administration of DDAVP, with no or only moderate short-term fluid restriction, yields urine osmolality values comparable to those after 22 hours of prolonged dehydration, and higher than those after combined pitressin and fluid deprivation test. No side effects have been observed with the procedure described.