Guthrie test can be used for the diagnosis of ?
**Core Concept**
The Guthrie test is a bacteriologic test used for the early detection of congenital infections, specifically bacterial infections such as **Neisseria meningitidis** and **Haemophilus influenzae**, which can cause meningitis and other severe conditions in newborns.
**Why the Correct Answer is Right**
The Guthrie test involves collecting a blood sample from a newborn's heel and adding a special reagent that inhibits the growth of bacteria. If the sample contains bacterial antigens, they will react with the reagent, resulting in a color change that indicates a positive test. The test detects the presence of **bacterial endotoxins**, which are part of the bacterial cell wall. The Guthrie test is particularly useful for detecting **Haemophilus influenzae type b (Hib)** infections, which can cause severe meningitis and other complications.
**Why Each Wrong Option is Incorrect**
**Option A:** The test is not used for diagnosing viral infections such as rubella or hepatitis.
**Option B:** The test does not detect the presence of fungal infections like candidiasis.
**Option C:** The test is not used for diagnosing parasitic infections such as malaria.
**Clinical Pearl / High-Yield Fact**
The Guthrie test is an example of a **screening test**, which is a preliminary test used to identify individuals who may be at risk for a particular disease or condition. It is an important tool in public health and preventive medicine.
**Correct Answer: C. Haemophilus influenzae.**