The purpose of this communication is (1) to discuss the errors introduced during the colorimetrie determination of phenolsulphonephthalein in the urine when the color of the dye is obscured by the bile pigments, and (2) to offer a method which permits of fairly accurate estimation of renal function, as expressed by the rate of excretion of phenolsulphonephthalein even though marked jaundice is present.
Rowntree and Geraghty1 noted in their paper, in 1910, that urinary and biliary pigments may be removed from urine by basic lead acetate. No details of the use of this substance were discussed. In 1921 a method was reported by Burwell and Jones,2 in which it was proposed that the use of a saturated alcoholic solution of zinc acetate precipitated both bile and blood pigments. The following paragraph is a quotation from the paper suggesting the use of zinc acetate.
Phenolsulphonephthalein is injected in the usual manner,