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Assessing Urinary Tract Junction Obstruction Defects by Methylene Blue Dye Injection
Published on: October 12, 2017
[Urinary concentration capacity in neonatal hydronephrosis]
G Orejas Rodríguez-Arango1, S García Vicente, C Rey Galán
1Sección de Nefrología Pediátrica, Hospital Central de Asturias, Facultad de Medicina, Oviedo.
Abstract:
In order to determine the renal concentration capacity in neonatal hydronephrosis, 10 micrograms of DDAVP were administered intranasally to 18 infants with hydronephrosis. Fluid intake was restricted to 50% of normal for 3 hours before and 6 hours after the administration of DDAVP. Maximal urine osmolality (mean +/- SD) was 348 +/- 180 mOsm/kg in 7 newborns younger than 21 days and 420 +/- mOsm/kg in 11 neonates between 22-50 days of age. Both osmolarities were inferior to the standard response to DDAVP reported in normal neonates. After 24 hours of clinical observation, we did not notice any secondary effects caused by this test.
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