HYPODIPSIA-HYPERNATREMIA SYNDROME - A PEDIATRIC CASE REPORT

The cases of chronic hypodipsis and hypernatremia represent a rarity, especially for the pediatric age group, and are mostly reported as “neurogenic” or “essential” hypernatremia. This paper describes a 2 3/12 yr old girl, 3rd child of healthy related parents, born from a spontaneous delivery (B.W.1200 g: 6.A.36 wks) admitted to our Hospital for hyperphagia, obesity (W.E. 40.1%), absence of thirst, intensified sweating and cyanosis of the extremities all of which begun about 9 months before admission. Poliuria was absent, there was no dehydration and blood pressure was normal. She showed tendency to hyperkinetic behaviour and psicomotor development was retarded. Hypernatremia (serum Na concentration up to 167 mEq/l) and serum osnolality up to 353 mOsm/ml were the major findings. The thyroid function tests (TRH) were consistent with secondary hypothyroidism and hyperprolactinemia. Other endocrine studies, and routine tests also for collagen disease resulted normal. Several ADH measurement showed mean levels of about 4 pg/ml and did not change appropriatly for serum osmolality values. Electroencephalographic recordings and cerebral NMR repeated more than once revealed normal results. A physiatric evaluation showed a chronic hypoventilation. At 3 7/12 yrs of age she was admitted in the our pediatric intensive care unit in coma and the data at that time showed a serum Na up to 170 mEq/l and an osmolality of 340 mOsm/ml. Our treatment consisted of the forced intake of 1,500 ml water/daily, hypocaloric diet and periodic oxidation with regular respitary exercises. Treatment with bromocriptine and L-Tiroxine was instituted. Under these regimens, the patient's situation definitely improved.