Updates in Immunoassays: Bacteriology

Extract

The use of immunological assays in the area of infectious disease has allowed for rapid and accurate identification of various bacteria, especially when identifying fastidious organisms such as Bordetella pertussis, Mycoplasma pneumoniae and Legionella pneumophilia.¹ Rapid latex agglutination assays, fluorescent antibody assays whether direct (DFA) or indirect (IFA), enzyme-linked immunosorbent assays (ELISA), enzyme immunoassays (EIA), lateral flow immunoassays also known as immunochromatographic assays and enzyme-linked fluorescent assays (ELFA) are available for in vitro diagnostic use to identify, screen for, or confirm the presence of infectious agents. The advent of the previously identified above rapid immunoassays has not only shortened turn-around times when compared to routine culture, but enabled the medical laboratory professional to report accurate results to the clinician in a timely manner ensuring administration of the appropriate antimicrobial therapy.

For many years, the serology department in most hospitals and medical centers was housed in the microbiology laboratory. Since several immunoassays are automated and require specific instrumentation to read and interpret results, most serological assays are now performed in the clinical chemistry department. Simple agglutination procedures however such as rapid plasma reagin (RPR) screening for syphilis along with group A strep, Salmonella, Shigella, and E. coli 0157 serogrouping are still performed in the microbiology and serology laboratories. This article will give an overview of some of the common and up-to-date serological methods and assays used in bacteriology whether performed in the microbiology, serology, clinical chemistry or the special chemistry department.