Question: A 25-year-old man with no personal or family history of interest, who enters Neurosurgery due to a cranial fracture due to a motorcycle accident. Three days later it begins abruptly with polyuria, polydipsia and intense thirst both during the day and at night. In the study conducted, a urinary volume of 7 liters with urinary osmolarity of 190 mOsm / L (90-1200) and plasma osmolarity of 292 mOsm / L (275-295) was observed. The plasma Na is 143 mmol / L. A water restriction test is performed and after checking that there is no increase in urinary osmolarity, a dose of 2 micrograms of desmopressin subcutaneously is administered. The posterior urinary osmolality is 410 mOsm / kg. What is the most likely diagnosis? 
 Options:  <1> Primary polydipsia. <2> Central diabetes insipidus. <3> Acute adrenal insufficiency. <4> SIADH. <5> Nephrogenic insipid diabetes.
2