Phenylketonuria overview
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief:
Overview
Overview
Phenylketonuria (PKU) is an autosomal recessive genetic disorder characterized by a deficiency in the enzyme phenylalanine hydroxylase (PAH). This enzyme is necessary to metabolize the amino acid phenylalanine to the amino acid tyrosine. When PAH is deficient, phenylalanine accumulates and is converted into phenylketones, which are detected in the urine.
Left untreated, this condition can cause problems with brain development, leading to progressive mental retardation and seizures. However, PKU is one of the few genetic diseases that can be controlled by diet. A diet low in phenylalanine and high in tyrosine can bring about a nearly total cure.
Historical Perspective
Historical Perspective
Pathophysiology
Pathophysiology
Classification
Classification
Causes
Causes
Screening
Screening
Differential Diagnosis
Differential Diagnosis
Epidemiology and Demographics
Epidemiology and Demographics
Risk Factors
Risk Factors
Natural History, Complications and Prognosis
Natural History, Complications and Prognosis
Diagnosis
Diagnosis
History and Symptoms
Physical Examination
Laboratory Findings
Other Diagnostic Studies
Treatment
Treatment
Medical Therapy
Primary Prevention
Secondary Prevention
Cost-effectiveness of Therapy
Future or Investigational Therapies
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