Question

The nurse explains that to detect inborn errors of metabolism, state law requires that certain diagnostic tests be performed on the newborn, such as:

1) blood glucose.
2) phenylketonuria (PKU).
3) blood urea nitrogen (BUN).
4) prothrombin time (PT).

Answer 1

Mandatory state tests for newborns, including blood glucose and phenylketonuria (PKU) screening, are essential for detecting inborn errors of metabolism. These tests can identify conditions that require immediate attention and management, such as the neurological damage associated with untreated PKU and blood glucose-related disorders like diabetes mellitus.

Step-by-step explanation:

Detecting Inborn Errors of Metabolism in Newborns

To detect inborn errors of metabolism, certain diagnostic tests are required by state law to be performed on the newborn. These tests can include measurements of blood glucose, screening for phenylketonuria (PKU), assessment of blood urea nitrogen (BUN), and prothrombin time (PT). These tests are critical for identifying metabolic conditions that can affect a newborn's long-term health.

For example, PKU is a metabolic disorder where the individual lacks sufficient activity of the enzyme phenylalanine hydroxylase. This leads to high levels of phenylalanine, which can cause neurological damage if not managed with a strict low-phenylalanine diet. As such, screening for PKU is mandatory in newborns in the United States and Canada.

Blood glucose tests are also crucial as they can indicate conditions like diabetes mellitus. The investigation of this disorder, as well as conditions like albuminuria and lactosuria, often begins with biochemical lab tests such as Benedict's test for the presence of sugar in urine.