To the Editor:
—In the June 1943 number of the Archives OF Internal Medicine, in the review of my book "La urobilina en el estado normal y patológico," it is said: "The book, alas, definitely puts an end to the hopes of both investigator in clinical laboratories and clinician that urobilin, so tempting to test for, is of any practical clinical diagnostic value."One of the more important conclusions at which I arrive in that discussion, however, is quite opposite to the reviewer's opinion. I definitely show that it has been proved by the experiments reported on that quantitative measuring of urobilin in urine or in blood (when present) is of considerable value for estimation of hepatic function. Quantitative determination of urobilin in bile is of distinct importance in the diagnosis of cholecystitis, and its measurement in feces is undoubtedly beneficial in certain special cases.