The Effect of pH on the Growth of Bacteria in Urine

Abstract

Yeaw determined the growth-promoting properties of normal human urine and the effect of pH on the growth of various microorganisms. Normal urine is a good culture medium at upper normal pH levels. The respective bacteriostatic and bactericidal pH levels of urine for different microorganisms encountered in infections of the urinary tract were as follows: Streptococcus hemolyticus 6 and 5.5 ; Strep. viridans 5.5 and 5; Staphylococcus anhemolyticus 4.9 and 4.5; Proteus vulgaris 4.75 and 4.5; Pseudomnas pyocyaneus 4.7 and 4.5; Escherichia coli 4.3 and 4; Aerobacter aerogenes 4.2 and 4. Application of these findings in the treatment of urinary-tract infections is discussed.