Dr. Bob,

I am from the Middle East and during a routine screening test, I tested positive for HIV (HIV Duo test). I did an Elisa card test and a western blot test which turned negative. The tests were done after 12 weeks of a needle stick exposure. Further, a PCR test also returned negative at 13 weeks (sample was sent to Germany). However, the lab technician warned that the blood sample was not "whole blood sample" and as such results may be incorrect. So another PCR was done by sending the blood sample to Mumbai - India (2 days transit). Here also it returned negative. Does false negatives happen in PCR testing due to the transit time for the sample to reach the lab? Does false negative happen in PCR testing because the blood sample is not whole blood sample? Should I do an elisa test again now that I have completed 6 months after the exposure? Please advise. Thanks in advance.

Mohammed

Hello Mohammed,

From the information you provided, it appears your fist HIV test (HIV Duo) was a false positive. The follow-up negative ELISA, Western Blot and two PCRs confirm your negative status. If you wish to repeat your ELISA at six months, that's certainly your option to do so. However, the reason to retest would be solely to put your mind at ease.

Dr. Bob