A 23 year old man visits his physician for routine examination. He has a history of HIV infection for 3 years and he is compliant with his medications. He is concerned about developing AIDS. Which of the following is the most useful test to address his concern? A- HIV antibody test B- HIV RT PCR C- HIV p24 antigen D- CD4 lymphocyte count http://medical-usmle.com/?p=910
