All of the following methods are used for the diagnosis of HIV infection in a 2 month old child, except –
**Core Concept**
The diagnosis of HIV infection in infants requires different approaches due to the presence of maternal antibodies. **HIV diagnosis** in this age group involves detecting the virus or its components directly.
**Why the Correct Answer is Right**
In a 2-month-old child, **HIV DNA PCR** or **HIV RNA PCR** are commonly used for diagnosis because they can directly detect the genetic material of the virus. **HIV p24 antigen** test is another method used for early detection of HIV.
**Why Each Wrong Option is Incorrect**
**Option A:** HIV DNA PCR is a correct method for diagnosing HIV in infants.
**Option B:** HIV RNA PCR is also used for diagnosing HIV.
**Option C:** HIV p24 antigen test is used, making it incorrect as the answer.
**Clinical Pearl / High-Yield Fact**
It's crucial to remember that **serological tests** like ELISA, which detect antibodies against HIV, are not reliable in infants under 18 months due to the presence of **maternal antibodies**.
**Correct Answer:** D.