“…17,20,21) Therefore, a remarkable feature is the musty odor caused by increased levels of phenylpyruvic acid, phenylacetic acid, and phenyllactic acid in the body fluids and urine of these patients. 17,22) When PKU is not treated early, it can cause behavioral problems, psychiatric symptoms, motor disorders, seizures, an eczematous rash, and irreversible intellectual disability. 1,23,24) Links have also been established between high Phe levels and epigenetic alterations in gene expression patterns in the brain, disrupted myelin production, impaired cerebral glucose metabolism (as seen on positron emission tomography imaging), the accumulation of amyloid plaque-like fibrils, and increased oxidative stress.…”