{"id":986,"date":"2010-06-23T11:10:32","date_gmt":"2010-06-23T15:10:32","guid":{"rendered":"http:\/\/blogs.nejm.org\/?p=986"},"modified":"2015-06-04T15:25:00","modified_gmt":"2015-06-04T19:25:00","slug":"combined-hiv-antibodyantigen-test-approved","status":"publish","type":"post","link":"https:\/\/blogs.nejm.org\/hiv-id-observations\/index.php\/combined-hiv-antibodyantigen-test-approved\/2010\/06\/23\/","title":{"rendered":"Combined HIV Antibody\/Antigen Test Approved"},"content":{"rendered":"<p><img loading=\"lazy\" decoding=\"async\" class=\"alignright size-full wp-image-987\" title=\"I-Want-U2get-HIV-Test\" src=\"http:\/\/blogs.nejm.org\/hiv-id-observations\/wp-content\/uploads\/sites\/2\/2010\/06\/I-Want-U2get-HIV-Test1.jpg\" alt=\"I-Want-U2get-HIV-Test\" width=\"175\" height=\"221\" \/>From the <a href=\"http:\/\/www.fda.gov\/NewsEvents\/Newsroom\/PressAnnouncements\/ucm216375.htm\" target=\"_blank\">FDA<\/a>:<\/p>\n<blockquote><p>The U.S. Food and Drug Administration today approved the first assay to detect both antigen and antibodies to Human Immunodeficiency Virus (HIV)&#8230; The highly sensitive assay is intended to be used as an aid in the diagnosis of HIV-1\/HIV-2 infection, including acute or primary HIV-1 infection. Since it actually detects the HIV-1 virus (specifically the p24 antigen) in addition to antibodies to HIV, the ARCHITECT HIV Ag\/Ab Combo assay can be used to diagnose HIV infection prior to the emergence of antibodies.<\/p><\/blockquote>\n<p>This is definitely progress, as it seems fairly obvious that combined antibody\/antigen detection is how we should optimally be diagnosing HIV infection.<\/p>\n<p>The fact remains that despite the increased sensitivity of antibody testing, some HIV cases are still missed\u00a0when patients\u00a0present with recently-acquired infection, too soon after viral transmission to have detectable antibody.\u00a0 One acute case we saw recently had reactive ELISA, but a completely negative Western blot\u00a0&#8212; anecdotally\u00a0this is becoming an increasingly common &#8220;negative&#8221; HIV test since ELISA has\u00a0cranked up the\u00a0sensitivity so much.<\/p>\n<p>The two settings where this new\u00a0test\u00a0might be particularly useful are in high-prevalence populations (where the incidence is higher) and when people seek testing soon after a risky exposure.<\/p>\n<p>Remaining questions include the cost of the new assay (both in literal terms and in lab personel resources), the predictive value of a reactive result in low risk settings, and how the p24 antigen here compares in sensitivity with HIV RNA measurement (our usual way of detecting acute HIV).\u00a0 On the last issue, at least <a href=\"http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/11187417\" target=\"_blank\">one past study<\/a>\u00a0suggested that p24 was less sensitive than HIV RNA, but that was a long time ago.<\/p>\n<p>(FYI, June 27 is <a href=\"http:\/\/www.hhs.gov\/aidsawarenessdays\/days\/testing\/\" target=\"_blank\">National HIV Testing Day<\/a>.\u00a0 Apologies for the grammatical error &#8212; &#8220;a HIV test&#8221; &#8212; in the above image, I love the poster.)<\/p>\n","protected":false},"excerpt":{"rendered":"<p>From the FDA: The U.S. Food and Drug Administration today approved the first assay to detect both antigen and antibodies to Human Immunodeficiency Virus (HIV)&#8230; The highly sensitive assay is intended to be used as an aid in the diagnosis of HIV-1\/HIV-2 infection, including acute or primary HIV-1 infection. Since it actually detects the HIV-1 [&hellip;]<\/p>\n","protected":false},"author":6,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,7,8],"tags":[73,81,423,447,687],"class_list":["post-986","post","type-post","status-publish","format-standard","hentry","category-hiv","category-misc","category-patient-care","tag-antibody","tag-architect","tag-hiv","tag-hiv-testing","tag-p24-antigen"],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/blogs.nejm.org\/hiv-id-observations\/index.php\/wp-json\/wp\/v2\/posts\/986","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.nejm.org\/hiv-id-observations\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.nejm.org\/hiv-id-observations\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.nejm.org\/hiv-id-observations\/index.php\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.nejm.org\/hiv-id-observations\/index.php\/wp-json\/wp\/v2\/comments?post=986"}],"version-history":[{"count":0,"href":"https:\/\/blogs.nejm.org\/hiv-id-observations\/index.php\/wp-json\/wp\/v2\/posts\/986\/revisions"}],"wp:attachment":[{"href":"https:\/\/blogs.nejm.org\/hiv-id-observations\/index.php\/wp-json\/wp\/v2\/media?parent=986"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.nejm.org\/hiv-id-observations\/index.php\/wp-json\/wp\/v2\/categories?post=986"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.nejm.org\/hiv-id-observations\/index.php\/wp-json\/wp\/v2\/tags?post=986"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}