Enfrentamiento de la Hiponatremia: Más allá de la corrección del sodio. A propósito de un caso clínico

Resumen

Hyponatremia is the most common electrolyte disorder in hospitalized patients (1). Given it can be a marker of an underlying disease it`s very important to search the cause through a complete history, physical examination and laboratory testing. We report a 52 years-old male with Diabetes Mellitus who consulted with a four day episode of nausea and vomiting. The Serum Sodium was 118 mEq/L. He had no neurological deficit.

At the beginning, hyponatremia was interpreted as generated by fluid loss but correction with saline solution was poor. Later we found that the patient had history of about 2 years of fatigue, weakness, myalgia, anorexia, frequent nausea, vomiting and diarrhea, loss of libido and decrease axillary and pubic hair. Urine Sodium was tested: 105 mEq/L, and Urine osmolality: 281 mOsm/L. Inappropriate ADH Syndrome (SIADH) was suspected. Thyroid-Stimulating Hormone (TSH) was normal and serum Cortisol < 1 ug/dL. Cerebral CT exhibited a sellar mass compatible with a Macroadenoma. Serum hormones disclosed moderatly high Prolactine, low Testosterone, low  T4  and low Growth hormone level. Finally, at visual field examination we found right temporal hemianopsia.

The patient was treated with steroids with a very good clinical response. Then a transsphenoidal surgery was performed and replacement of the other hormones was started. Now the patient remains asymptomatic doing normal life