What Does a High or Low Lyme Disease Result Mean?
A high Lyme result usually means antibodies were detected; a low result usually means they were not. Learn how IgM, IgG, ELISA, Western blot, and two-tier testing change interpretation.
Infectious Disease
Syphilis Blood Test: What It Measures, Preparation, and Results
A syphilis blood test looks for antibodies related to Treponema pallidum infection. Learn what RPR, VDRL, EIA, CIA, and TPPA results mean, how to prepare, when to test, and what to do after reactive or discordant results.
HIV Blood Test: What It Measures, Preparation, and Results
An HIV blood test checks for signs of HIV infection using antibodies, p24 antigen, or viral RNA. Learn which test is usually ordered, when to test after exposure, how to prepare, what results mean, and how cost and privacy work.