Predictive value of fractional excretion of filtered sodium for hypertension in acute post-streptococcal glomerulonephritis.
The course of acute post-streptococcal glomerulonephritis was followed in 81 children, 66 of whom were hypertensive on admission. Sixty-one hypertensive patients were available for follow-up; in seven (11.5%), hypertension recurred 1 to 9 days after initial blood pressure elevation had returned to normal. Thirteen initially normotensive patients were available for follow-up; six (46%) developed hypertension 1 to 9 days after admission. Initial FENa was less than or equal to 0.5 in all 13 patients with recurrence of initial hypertension or who developed initial hypertension while under observation, and in another 25 patients who did not have this course. On the other hand, FENa was greater than 0.5 in 36 patients, none of whom had recurrence of initial hypertension or developed hypertension while under observation. Therefore, an admission FENa less than or equal to 0.5 seems to be an accurate predictor for development of hypertensive episodes.