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3. was evidenced by kinetic analysis of sera drawn during the time course of the infection. Controls consisted of 98 serum samples from healthy individuals, 93 serum samples from patients hospitalized in intensive care units, and 39 serum samples from patients with deep mycoses. The sensitivities and specificities were 40 and 98% and 53 and 94% for mannanemia or antibody detection, respectively. These values reached 80 and 93%, respectively, when the results of both tests were combined. These observations, which clearly demonstrate a disparity between circulation of a given mannan catabolite and antimannan antibody response, suggest that use of both enzyme immunoassays may be useful for the routine diagnosis of candidiasis. Yeasts of the genusCandidahave been recognized as important agents of hospital-acquired infections. They have become the fourth most common isolate recovered from Amoxicillin trihydrate blood cultures in the United States (23). Similarly, the rates of candidemia have increased substantially in Europe as well (69,70). Candidal infections occur on both medical and surgical services, but approximately half of them occur in surgical intensive care units. Depending on the hospital ward, the mortality rate attributable to candidemia ranges from 40 to 60% (46,73). Difficulties in establishing an early and specific diagnosis of candidal infection are among the recognized reasons for such high mortality rates. The difficulties for Amoxicillin trihydrate clinical diagnosis lie in the absence of specific clinical signs (1,4). Difficulties for biological diagnosis lie in the opportunistic character of yeasts. Their presence in normally colonized body sites of immunocompromised patients does not prove infection, and they are rarely isolated from infected deep organs or tissues including blood (43,52,55). Efforts have been made to find either antibodies againstCandida albicansmolecules orCandida-derived molecules whose presence in patient sera could indicate deep-tissue invasion. Tests have been developed to detectC. albicansproteins (35,39,71), metabolites (62), DNA (5,15,63), and polysaccharides. In this regard, a sensitive biochemical test for the detection of glucan, a major structural polysaccharide of the cell wall, has been made commercially available, and promising data from a large number of centers have been documented with a large number of serum samples from patients (29,39,40,42). Like glucans, mannans are major components of theC. albicanscell wall, making up to 7% of the cell dry weight (26a). By contrast to glucans, mannans are noncovalently bound at the cell wall surface and are highly immunogenic (17). They correspond to a large and complex repertoire of mannopyranose units linked by either -1,6, -1,3, -1,2, or -1,2 linkages (61). Among these units, oligomannose sequences corresponding to epitopes specific for human being and animal antibodies, either polyclonal or monoclonal, have been recognized; antibody recognition depends on both the type of linkage linking the mannose devices and the space of the mannose chain (17,19,22,32,47,61,65). These epitopes may also be shared from the glycosidic moiety of a large number of different mannoproteins or glycolipids, reinforcing the quantitatively major character of mannose residues inC. albicanscells (64,65). The use of mannan antigenemia (mannanemia) detection for the immunodiagnosis Amoxicillin trihydrate of systemic candidiasis was suggested by Weiner and Coats-Stephen (72) about two decades ago. Efforts to improve the immunological detection of mannan involved the use of immune complex dissociation by heating sera before overall performance of the test and the use of monoclonal antibodies that react with defined epitopes (21,22,53). These attempts resulted in standardization and a high level of specificity. These checks, however, like the commercially available PastorexCandida, still lack level of sensitivity due to the quick clearance of the antigen from individuals sera and the test format (latex agglutination) (21,37,39,50). In contrast to mannanemia detection, checks based on antimannan antibody detection have been used less and less in the medical diagnostic mycology laboratory because they have been explained both as poorly specific and as poorly sensitive. The reasons for the poor specificity and level of sensitivity could be attributed to the elevated antibody titers in greatly colonized but uninfected hospitalized individuals (44) and the possible lack of antibody response in infected immunocompromised individuals (24). Although antimannan antibody and mannan antigenemia were used singly, to our knowledge, simultaneous assays for both parts in the same sera have Rabbit Polyclonal to PPIF never been performed. Therefore, in this study, sera from individuals with recorded candidiasis were tested for the presence of mannanemia and antimannan antibodies. To facilitate the combined detection of both mannan and its antibodies, we (i) developed a double-sandwich enzyme immunoassay (EIA) using the monoclonal antibody used in the PastorexCandida, with increased level of sensitivity, and (ii) developed an EIA for the simultaneous detection of antibodies. A total of 162 serum samples.