DR.MARK I have a patient,26 year old male non iv drug user came to me after a possible exposure to the hiv virus with 2 slightly swollen lymphnodes in his neck (non painfull)no other symtoms,he has had them for 2.5 months when I asked him when his exposure was he knew his exact date (6.5 months ago)tested him with a third generation antibody test (which a surprise to both of us was negitive)would you agree to run a pcr dna/rna test to rule it out.after speaking to the patient he informed me he had taken a pcr dna at 27 days post exposure (he and his girlfriend were trying to have a baby)seeing all that I am troubled,I practice in a very small town in the mid west and do not have alot of experience in the matter,if the lymphnodes were to be swollen due to hiv would'ent they be all through out the pateints body,and would'ent almost 18 weeks be a little long for ars,and with the lymphnodes being swollen for 2.5 months would'ent he of tested positive or atleast intermid. I look foward to your answer

Isolated swollen lymph nodes in the neck would be unusual for acute HIV infection. We usually see diffuse adenopathy. If the contact date is accurate, then 6 months post exposure is sufficient time for testing accuracy.