Which of the following does not establish the diagnosis of congenital CMV infection in a neonate?
**Core Concept**
Congenital CMV infection is a significant cause of neonatal morbidity and mortality. The diagnosis of congenital CMV infection can be established through various methods, including serological tests, PCR, and histopathological examination.
**Why the Correct Answer is Right**
The correct answer is **A. CMV IgG antibody detection in the mother**. This is because maternal CMV IgG antibodies can cross the placenta and lead to a false-positive result in the neonate. To confirm congenital CMV infection, it is essential to detect CMV DNA in the neonate's urine or saliva. Detection of CMV IgM antibodies in the neonate is also a reliable indicator of congenital infection. However, maternal IgG antibodies can interfere with the interpretation of these results.
**Why Each Wrong Option is Incorrect**
* **Option B:** Detection of CMV DNA in the neonate's urine or saliva using PCR is a reliable method for diagnosing congenital CMV infection.
* **Option C:** Histopathological examination of the neonate's tissues, such as the liver or brain, can reveal characteristic features of CMV infection, including inclusion bodies and inflammatory changes.
* **Option D:** Detection of CMV IgM antibodies in the neonate's serum is a specific indicator of congenital CMV infection, as these antibodies are not transferred from the mother.
**Clinical Pearl / High-Yield Fact**
When diagnosing congenital CMV infection, it is essential to consider the timing of the infection and the presence of symptoms. Neonates with congenital CMV infection often present with symptoms such as petechiae, hepatosplenomegaly, and respiratory distress.
**Correct Answer:** A. CMV IgG antibody detection in the mother, because it is a false positive