Prevention of Pyelonephritis by Water Diuresis: Evidence for the Role of Medullary Hypertonicity in Promoting Renal Infection *

Abstract

Chronic water diuresis was induced in rats by adding glucose to their drinking water. The concentrations of sodium and urea and the total calculated osmolality of inner medulla were significantly reduced by water diuresis, whereas tissue concentrations of ammonia and potassium were unchanged. Water diuresis protected against 2 types of experimental pyelonephritis, that produced by intravenous inoculation of Candida albicans and of Staphylococcus aureus. These data support the view that the habitual hypertonicity of the renal medulla is an important determinant of the special susceptibility of this tissue to infection.