TY - JOUR T1 - A clinical overview of autoantibodies in general practice rheumatology JF - British Journal of General Practice JO - Br J Gen Pract SP - e599 LP - e601 DO - 10.3399/bjgp14X681601 VL - 64 IS - 626 AU - Adrian YS Lee AU - Eugene BH Ang Y1 - 2014/09/01 UR - http://bjgp.org/content/64/626/e599.abstract N2 - Rheumatic diseases encompass a vast spectrum of disorders that range from localised to complex systemic illnesses affecting joints and connective tissues. They are often associated with pain and can be extremely debilitating to the sufferer. Many non-specific presentations may make diagnosis problematic. Key tests used to facilitate this are the serological autoantibody tests that measure antibodies against self antigens.When should they be ordered?Within the rheumatology framework, some clues in the history and examination that may prompt the GP to order autoantibody tests include: Raynaud’s phenomenon; thinning of the skin; vasculitic-type rashes; keratoconjunctival sicca and xerostomia; uveitis; isolated photophobia; unexplainable myalgia, arthralgia, or fatigue; or evidence of unexplained acute kidney injury. Obviously, the suspected disease entity will dictate which autoantibody test to order, as will be reviewed below. There are also other times when other non-rheumatic clinical situations warrant autoantibody tests, for example, organ-specific autoimmune conditions, and these should be considered as well.Healthy individuals, particularly older people, may also have positive autoantibodies in low concentrations. Although these are not perfect as markers for specific diseases, with reasonable pretest probability, they are useful for ruling in and out the possibility of certain diseases. As autoantibodies are rarely sufficient alone to do this, other appropriate tests to assist, including basic blood workups, should be ordered as well.How are they reported?Most autoantibodies are measured using immunoassays (for example enzyme-linked immunosorbent assay [ELISA]), and are read as a titre … ER -