IgM (Immunoglobulin M) er en type antistoff som fungerer som kroppens første forsvarslinje mot infeksjoner. Det spiller en nøkkelrolle i immunsystemets tidlige respons ved raskt å gjenkjenne og angripe inntrengende patogener. Ved diagnostisk testing måles nivåer av IgM for å oppdage nylige infeksjoner, slik som Lyme sykdom forårsaket av Borrelia burgdorferi. Tilstedeværelsen av IgM-antistoffer i blodet indikerer vanligvis en nylig eksponering eller aktiv infeksjon, og gir viktig informasjon om de tidlige fasene av immunresponsen.
IgM testing is important in the diagnosis of Lyme disease as it helps detect early infection. IgM antibodies to Borrelia burgdorferi typically appear within a few weeks of infection, making this test useful for identifying recent exposure to the tick-borne bacterium.
Individuals who have been bitten by a tick or have been in areas where Lyme disease is common and present with symptoms such as fever, rash (erythema migrans), fatigue, and joint pain should undergo IgM testing. Early detection is crucial for effective treatment.
Positive IgM results, especially when combined with symptoms and possible tick exposure, usually lead to prompt treatment with antibiotics. Early treatment is crucial to prevent the progression of Lyme disease to more severe stages that can affect the joints, heart, and nervous system.
False positives in IgM tests can occur due to cross-reactivity with other bacteria, previous infections, or certain autoimmune disorders. This is why positive results from an IgM test are usually confirmed with additional testing, such as the IgG antibody test or Western blot.