Phenylketonuria with Normal Intelligence and Gowers' Muscular Dystrophy

Phenylketonuria is a rare inborn error of meta- bolism, which is believed to be associated almost always with some degree of mental retardation.The great majority of those affected are idiots or imbeciles; any with an intelligence quotient over 65 are rare enough to merit reporting (e.g., Low, Armstrong and Carlisle, 1956).Gowers' peripheral muscular dystrophy is also a very unusual disease in children.The case reported here showed this extremely rare combination of Gowers' muscular dystrophy, phenylketonuria and an intelligence quotient of over 100.It appeared important, therefore, to determine any metabolic or other differences between this case and other phenylketo- nurics in the hope of throwing more light on the disease process.Case History A.T. was the fourth child of a family of five, born on July 29, 1948, a full-term male infant, weighing 6 lb. 3 oz.His progress was normal at first, and he used his hands well as a baby, but did not walk until the age of 20 months.He played normally with toys.In June, 1951, when he was almost 3 years old, his mother noticed that he was holding the right hand as if there were no power in that wrist.She then noticed that he could no longer hold a knife in the right hand nor open a door with it.In January, 1952, he was found to have bilateral wrist drop, with hyperextension of the metacarpo-phalangeal joints.There was no obvious weakness elsewhere.