What could cause discrepancies in HIV test results?

Hello doctor,

A few months ago, I got a small cut while shaving outside, and though initially worried due to a crowded shop, I later tested negative for HIV using ELISA and CLIA after two months. However, an internet search prompted me to take an RNA PCR test, which surprisingly showed a positive result.

Concerned, I contacted the diagnostic center, and subsequent tests (rapid CLIA, Elisa, and RNA PCR) returned negative. The center explained that initial false positives can occur and assured me there was no error during blood collection. Despite this reassurance, I still felt anxious, so I retested with Elisa after two weeks, and the results were negative.

Please help.

Thank you.

Hi doctor,

Thank you for your reply.

I am currently not concerned about contracting an infection at the barber shop. My primary worry is understanding why the initial RNA PCR test yielded false positive results.

Could it be due to using the wrong syringe during blood collection?

When I raised the concern with the diagnostic center, they conducted a second RNA PCR, CLIA, and ELISA test, all of which came back negative. The diagnostic center assured me they carefully rechecked, confirming the absence of infection. There is a three-day gap between the first and second RNA PCR tests.

Thank you.

Hi doctor,

Thank you for your reply.

As mentioned, after complaining, they conducted several tests, including RNA PCR, and confirmed all results were negative.

I also underwent another ELISA after two weeks, which also yielded a negative result. Regarding the initial concern about using the wrong syringe, can the reliability of the RNA PCR test after three days and the Elisa test after 16 days be trusted?

Thank you.