Biochemical screening of newborn infants by heelprick blood samples is performed by using the –
**Core Concept**
The biochemical screening of newborn infants by heelprick blood samples is a crucial public health measure aimed at early detection of congenital disorders, particularly those related to metabolic and genetic conditions. This screening involves the analysis of various biochemical markers in the blood to identify potential abnormalities. The screening is typically performed using a blood sample obtained by pricking the heel of the newborn.
**Why the Correct Answer is Right**
The biochemical screening of newborn infants is performed using a tandem mass spectrometry (MS/MS) technique, which is highly sensitive and specific for detecting various biochemical markers. The MS/MS technique involves the separation and identification of various ions present in the blood sample, allowing for the detection of specific biochemical markers associated with congenital disorders. This technique is particularly useful for detecting disorders such as phenylketonuria (PKU), hypothyroidism, and various amino acid disorders.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not accurately describe the biochemical screening technique used for newborn infants. Although fluorescence polarization immunoassay (FPIA) is a common laboratory technique, it is not typically used for biochemical screening of newborns.
* **Option B:** This option is incorrect because it is not a specific biochemical screening technique. Although gas chromatography-mass spectrometry (GC-MS) is a sensitive analytical technique, it is not the primary method used for biochemical screening of newborns.
* **Option D:** This option is incorrect because it is not a specific biochemical screening technique. Although enzyme-linked immunosorbent assay (ELISA) is a common laboratory technique, it is not typically used for biochemical screening of newborns.
**Clinical Pearl / High-Yield Fact**
It is essential to note that the biochemical screening of newborn infants is usually performed between 24 and 72 hours of birth, and the results are typically available within 2-3 days. Early detection and treatment of congenital disorders can significantly improve the outcome for affected infants.
**Correct Answer: C. Tandem mass spectrometry (MS/MS) is used for biochemical screening of newborn infants.**