Canadian Society for Medical Laboratory Science (CSMLS) Practice Exam

Which patient group is primarily tested for phenylketonuria (PKU)?

1. Newborn

2. Cancer

3. Mentally handicapped

4. Geriatric

The correct answer is: Newborn

Phenylketonuria (PKU) is a metabolic disorder that is primarily identified through newborn screening programs shortly after birth. This testing is internationally recommended to detect PKU early, as prompt diagnosis allows for dietary management that can prevent the cognitive impairment and other health issues associated with untreated PKU. Newborns are tested because they are at a critical age where early intervention can lead to significantly better health outcomes and prevent the development of severe intellectual disabilities. While other groups, such as individuals with intellectual disabilities, may also be discussed in the context of PKU due to potential afflictions resulting from the disorder, the screening and testing protocols are specifically targeted at newborns to ensure early detection. Thus, it is in newborns that we primarily focus our testing efforts for PKU. The other patient groups listed, such as those experiencing cancer, geriatric patients, or individuals with intellectual disabilities, do not undergo routine PKU screening, making newborns the appropriate and primary group for testing.