Phenylketonuria
1 Boston City Hospital, 818 Harrison Avenue, Boston 18, Massachusetts
I would like to comment on a statement made in the August 1957 issue of Pediatrics. Dr. Richmond Paine, in his article entitled "The Variability in Manifestations of Untreated Patients with Phenylketonuria" states that "diagnosis can be made only by the testing of a fresh urine specimen or by determination of the concentration of phenylalanine in the plasma."
I wish to expand on the first part of this statement. I have performed the ferric chloride test on the urines of several untreated phenylketonuric patients, and have observed the following:




