Final answer:
In a patient's serum, the presence of specific IgM antibodies against a pathogen is detected using agglutination tests with latex beads and might indicate an infection. Agglutination tests and assays help identify antibody titers and presence of antigens. Additional testing is needed to confirm current infections as antibodies can persist from past infections.
Step-by-step explanation:
The agglutination test is a laboratory procedure used to detect the presence and concentration of antibodies or antigens in a patient's serum. In this context, IgM antibody levels against a specific pathogen or antigen are found by mixing patient serum with latex beads coated with an antigen or antibodies. If agglutination occurs, it indicates the presence of antibodies in the serum that recognize and bind to that specific antigen, a reaction which can help diagnose an infection.
Two key tests in this process include the hemagglutination assay (HIA), which tests for antibodies against viruses like the influenza virus, and the neutralization assay, which tests for the ability of antibodies to prevent virus-induced plaque formation. In HIA, the highest dilution of patient serum that blocks agglutination denotes the titer of antibodies present. The presence of antibodies alone, however, does not confirm a current infection without further testing, as antibody levels could be from a past infection.