Current trends in immunodiagnosis of candidiasis and aspergillosis

Abstract

The methods and reagents currently used for the immunodiagnosis of aspergillosis and candidiasis are reviewed. Problems associated with these techniques and approaches to resolving these problems are discussed. Latex agglutination and precipitin tests are used for detection of antibody in immunocompetent hosts. However, these tests are apparently inadequate when applied to the diagnosis of systemic candidiasis in compromised hosts. Enzyme immunoassays ( EIAs ) and radioimmunoassays (RIAs) can be used to detect antibodies in immunocompetent and compromised patients, but their value is limited because antibodies to the Candida species are detectable in healthy as well as colonized and infected patients. EIAs and RIAs are, however, promising for detection of antigenemia in patients with aspergillosis or candidiasis, and gas-liquid chromatography has been developed for the quantitation of serum arabinitol and mannose in candidiasis. Antigens of the Aspergillus and Candida species may circulate in patients' sera in the form of immune complexes. These may readily be dissociated by a variety of methods to permit the detection of diagnostically important antigens. Studies are being carried out to increase the sensitivity and reliability of these tests through the use of monoclonal antibodies and purified, clinically relevant antigens.