ENHANCED IGE RESPONSE TO CANDIDA-ALBICANS IN POSTOPERATIVE INVASIVE CANDIDIASIS

Background Invasive candidiasis is a life-threatening complication pro blem in postoperative and immunocompromized patients, e.g. those treat ed by intensive care. Candida is frequently cultured from the mucous m embranes of hospital patients and fungal cultures offer little diagnos tic help. Other diagnostic methods, such as blood cultures, serology a nd diagnostic imaging techniques produce results too late and, if posi tive, low sensitivity. Objective To study the value of Candida-specifi c antibodies, especially those of IgE class, in diagnosing invasive Ca ndida infection. Methods The immunoglobulins IgE, IgG and IgM response s to antigens of Candida albicans in the sera of 14 patients with cult ure, biopsy and/or autopsy proven postoperative invasive candidiasis a nd of 11 colonized and 19 non-colonized operated patients were studied by mannan radioallergosorbent test (RAST), mannan enzyme-linked immun osorbent assay (ELISA) and immunoblotting. Results Detection of IgE an tibodies to C. albicans polysaccharide (mannan) and protein antigens p roved specific and sensitive in diagnostics of invasive candidiasis af ter major abdominal surgery. IgE rose early in the course of the infec tion and the method made a clear distinction between invasive infectio n and mucous colonization. Immunoblotting for protein antibodies was m ost sensitive while nitrocellulose-RAST for mannan antibodies was most specific. The combined use of immunoblotting and RAST increased the s ensitivity and the specificity. Determinations of anti-Candida IgG and IgM antibodies had low sensitivity and specificity. Conclusion Critic ally ill patients with invasive candidiasis develop IgE antibodies to Candida antigens probably because of disturbed TH1/TH2 responses. Dete rmination of specific IgE antibodies can be used as a diagnostic aid i n the early stage of invasive Candida infection.