Donoghue et al1 reports a hyponatremic seizure in a 10-year-old boy with nocturnal enuresis who was treated with desmopressin. The hyponatremia apparently developed without a history of excessive fluid intake, the evidence for which includes a lack of history of excessive fluid intake and the absence of physical signs of hypervolemia 24 hours before the seizure. The child was hypertensive at presentation with the seizure. Notwithstanding the absence of peripheral edema, this suggests the presence of hypervolemia.
Robson WLM, Leung AKC. Hyponatremia in Children Treated With Desmopressin. Arch Pediatr Adolesc Med. 1998;152(9):930-931. doi: