CEDIE   05498
CENTRO DE INVESTIGACIONES ENDOCRINOLOGICAS "DR. CESAR BERGADA"
Unidad Ejecutora - UE
congresos y reuniones científicas
Título:
Diagnostico diferencial en la poliuria y polidipsia: variaciones cl¨ªnicas y de laboratorio en la prueba de restricci¨®n h¨ªdrica en niños.
Autor/es:
M TROIANO,; A CHIESA; A KESELMAN,; G ROPELATO,; I BERGADA,
Lugar:
Lima Peru.
Reunión:
Congreso; XX Reunion Anual de SLEP; 2008
Institución organizadora:
SLEP
Resumen:
Diagnosis of Central Diabetes Insipidus (CDI) is based on clinical
and laboratory studies. Although the WDT is generally used for a
definite diagnosis, scarce information exists in children regarding its
clinical and laboratory findings. To clarify these issues we studied 31
children (aged 7.25 ¡À 5.0 years) that underwent a WDT to rule out
CDI Weight and urine output were measured hourly. Initial and final
plasma and urinary osmolality (freezing point), and plasma ADH
(extracted RIA) were measured. Final plasma ADH was plotted on a
nomogram related to serum osmolality in a normal population.
The positive predictive value of a final U/P Osm ratio(f U/POsm)
¡Ü 1.5 towards an inadequate final plasma ADH was 95%, and the negative
predictive value of 72%, with a diagnostic efficiency of 83%.
So, patients were grouped according to the f U/POsm in: Group A
(n = 20) ratio < 1.5, and B (n = 11) > 1.5. Patients from group A had
a significant decrement of weight (p < 0.05) and higher urine output
(p < 0.006) than group B. Increment of pADH after the test was significantly
lower in group A (0.24 ¡À 1 pg/ml) vs group B (2.47 ¡À 2.8
pg/ml), p = 0.015.
In summary, a decrement in body weight as well as the urine output
during this test are useful information to define pediatric patients
with a real incapacity to concentrate the urine. Moreover, the measuring
of plasma ADH enabled us to establish that a cut-off f U/P Osm
ratio ¡Ü 1.5 is likely associated with inadequate plasma ADH secretion,
resulting in the best tool for the differential diagnosis in children
with polyuria and polydipsia.