Reversible Bone-Marrow Vacuolizations in Phenylketonuria

PHENYLKETONURIA is an inherited disorder of amino acid metabolism characterized biochemically by a deficiency of hepatic phenylalanine hydroxylase, inability to convert phenylalanine to tyrosine and accumulation of phenylalanine and its metabolic products in various body fluids.1 2 3 4 5 6 7 8 9 10 11 Clinically, the disorder is associated with mental retardation, a variety of neurologic findings, alterations in skin pigmentation and eczema.12 13 14 15 16 The mental retardation and other clinical manifestations have been prevented by the early use of restricted phenylalanine diets.17 18 19 20 21 22 23 24 The application of the Guthrie screening test25 in the neonatal period has greatly facilitated the early diagnosis of this disorder.Phenylketonuric children become anemic,26 27 28 and it is . . .