The moment of hyponatremia occurence Pneumonia Sepsis Convulsions Acute renal failure 14 (7, 8%) 8 (4, 4%) 8 (4, 4%) 5 (2, 78%) 4 (1, 92%) 2 (0, 96%) 2 (0, 96%) 3 (1, 4%) Hyponatremia (180) Normal (n=208) 17 Occurrence of hyponatremia is most prevalent in the first day of the disease, accounting for 15%, the percentages of patients with the occurrence of hyponatremia from day 1 to day 4, from day 5 to day 8, and between day 9 and after day 14 are 42.23%, 32.72% and 16.67%, respectively (Figure.