Both Quest and LabCorp have false positive results commonly for HSV-2, and lately, I’ve been seeing for HSV one as well, when compared to the gold standard western blot. Quest does not routinely do their inhibition assay as a confirmatory test unless the clinician orders it. And the rate of false positives with quest is high. It is also Highwood LabCorp but LabCorp has been doing a supplemental test that, when negative, agrees virtually all the time with a negative Western blood. The problem is that LabCorp also has false positives on the supplemental test. We now have 120 people with a positive IgG and a positive supplemental from LabCorp who are negative by western blot. The state of herpes antibody testing right now is not good at all.
Terri