Ependymoma of the neurohypophysis and hypernatremia in a horse
Heath, S.E.; Peter, A.T.; Janovitz, E.B.; Selvakumar, R.; Sandusky, G.E.
Journal of the American Veterinary Medical Association 207(6): 738-741
1995
ISSN/ISBN: 0003-1488 PMID: 7657573 Document Number: 441749
A 2-year-old Standardbred gelding was examined because of prolapse of the third eyelid; myoclonus of the muscles of the head, neck, and forelimbs; and persistent tail swishing. The horse had a high plasma sodium concentration but was not drinking water. The hypernatremia could not be corrected by means of IV administration of fluids, and the horse became worse and, 6 days later, died. At necropsy, a tumor was found to be compressing the neurohypophysis and the area in the brain in which the thirst centers are believed to be located. It is believed that hypernatremia in this horse was a result of altered thirst.