Síndrome poliúrico / Poliuric syndrome

Se sospecha Síndrome Poliúrico (SP) cuando el volumen urinario excede en 2 a 3 veces lo esperado para la edad o cuando a raíz de una deshidratación o restricción hídrica no se produce concentración urinaria adecuada. El volumen y la osmolaridad de los líquidos orgánicos se regulan con gran precisión gracias a la actividad de la hormona antidiurética (HAD), producida en el eje hipotálamo hipofisiario, que maneja la permeabilidad del agua de los túbulos distales y colectores renales. El SP se clasifica en dos grandes grupos: 1) con niveles plasmáticos bajos de HAD (diabetes insípida central DIC o neurogénica y polidipsia primaria) y 2) con niveles plasmáticos normales de HAD (diuresis osmótica y diabetes insípida nefrogénica DIN). El diagnóstico diferencial se hace con la prueba de deprivación acuosa y el tratamiento consiste en reemplazo hormonal con HAD en DIC y en la DIN reducción del aporte calórico proteico con la ingesta libre de agua, más diuréticos tiazídicos y antiinflamatorios. En el presente artículo se hace una revisión actualizada del SP.

Syndrome of inappropriate antidiuretic hormone secretion [SIADH] in a pediatric ICU

Fifty hyponatremic children were recruited from those who have been admitted to the pediatric intensive care unit [PICU] at Ain Shams University hospitals in a 4 month period. Their ages ranged between 5 months and 9 years. They were 27 males and 23 females. The fifty cases were categorized under 3 clinical groups; pneumonia [19], status asthmaticus [17] and meningitis [14]. All cases were subjected to measurement of serum and urinary sodium as well as serum and urine osmolality in addition to clinical and laboratory evaluation of the underlying disease. It was found that SIADH is a common cause of hyponatermia in the PICU [60%] with more prevalence among cases of meningitis group. However severity of SIDAH does not vary with the cause or severity of the underlying disease. We conclude that SIADH should be considered a common problem in PICU especially among hyponatermic cases. Therefore routine measurement of urinary sodium and osmolalities of both serum and urine are recommended in hyponatremic cases admitted to PICU so as to pick up those who would pass to SIADH and hence adequately managed