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Visceral candidiasis is nonspecific in the clinical presentation and a microbiological diagnosis is often difficult to make. Currently, several techniques are available for detection of the antigen and antibody and/or fungal product. We report the results of an investigation in immunodiagnosis and blood biochemical diagnosis of visceral candidiasis and suggest the cutoff limits of positive, from these findings and those reported by others. The efficiency and specificity were 36.4% approximately 60% and 94% approximately 100% for the mannan detection kit from Kyokuto Co., Ltd. and 57.1% approximately 100% and 25% approximately 69.6% for the CAND-TEC, and 28.6% and 91.7% for PASTOREX CANDIDA. For kits using a blood biochemical assay; the efficiency and specificity were 10% approximately 56.7% and 91.4% approximately 100% with detection of D-arabinitol (cutoff limits; 20 mumol/ml < or =), and 70% approximately 75% and 91.7% approximately 100% for Fungal Index (cutoff limits; 60pg/ml < or =). We investigated the evaluation of LA test to detect candidal mannan antigen in sera obtained from experimental gastric candidiasis of mice with or without treatment. There was a good correlation between the change of the titer of mannan antigen and the severity of infections, and gastric lesions healed histopathologically 3 weeks after disappearance of mannan antigen in sera obtained from mice treated with an antifungal agent. These findings indicate that the antifungal therapy is necessary for more than 3 weeks after the candidal mannan antigen disappeared from sera.

To evaluate serum markers for the diagnosis of Candida pyelonephritis, levels of D-arabinitol, candidal mannan antigen and candidal protein antigen were measured using an enzymatic fluorometric assay, an enzyme immunoassay and a latex agglutination assay, respectively. The study group comprised 36 patients with candiduria (11 disseminated candidiasis, 9 Candida pyelonephritis and 16 colonization) and 27 without candiduria. The D-arabinitol/creatinine ratio was the only marker that differentiated between Candida pyelonephritis and colonization (p < 0.01). Using the cut-off values (1.4 mumol/mg of D-arabinitol/creatinine ratio, 0.28 of mannan/creatinine ratio (x 10(4)) and 1:4 of protein antigen titer) D-arabinitol/creatinine ratio showed the highest sensitivity in Candida pyelonephritis (77.8%) as compared to mannan/creatinine ratio (55.6%) and protein antigen titer (11.1%) although there were no differences in specificity, positive predictive value or negative predictive value. These results suggest that D-arabinitol/creatinine ratio is the most useful marker of Candida pyelonephritis.

Two patients with acute myeloblastic leukemia are described who developed fungemia due to Trichosporon cutaneum. Fungemia occurred at the leukocyte nadir following the administration of anti-cancer chemotherapy. One patient was cured but the other died. Both patients received prednisolone continuously and had central venous catheters in place for parenteral hyperalimentation. T. cutaneum isolates were resistant to 5-fluorocytosine and moderately susceptible to fluconazole. One case was complicated by endophthalmitis due to T. cutaneum; this is the second report of such a complication in the world. We investigated the serum levels of beta-D-glucan, D-arabinitol, and Candida antigen (CAND-TEC); beta-D-glucan was elevated in both cases, which suggests that simultaneous measurements of these laboratory values are useful for the diagnosis and possibly for the evaluation of therapy for this fungal infection.

Repeat serum samples from 22 patients with proven disseminated candidiasis and 42 with simple peripheral colonization were assayed for Candida antibodies by coelectrosyneresis, immunoprecipitation, and A and B immunofluorescence, for metabolites by D-arabinitol measurement, and for antigens by the mannan immunoassay and Cand-tec latex agglutination (mean number of samples tested, 2.5 per patient). For the antibody and metabolite assays, the results showed no statistical difference between the two groups. By contrast, the results of both antigen assays were positive for a significantly larger number of patients with disseminated candidiasis than of those with simple peripheral colonization. Results were regardless of whether the patients were neutropenic. They were not predictive of death. We calculated that the mannan antigen assay had 29% sensitivity and 97% specificity for the diagnosis of disseminated candidiasis. Likelihood ratios of a positive and a negative result of this test were 9.2 and 0.7, respectively, for this diagnosis. In the latex agglutination test, likelihood ratios were 2.5, 1.5, 1.6, and 0.3 when the test was positive for dilutions of 1/8, 1/4, and 1/2 and was negative, respectively.

In this study, we measured D-arabinitol, candida antigen and beta-glucan in the rabbit model of systemic candidiasis. It was recently reported that the factor G, one of the coagulation enzymes from the horseshoe crad amebocyte lysate, reacts with beta-glucan or polysaccharide from fungus, and not with endotoxin. The newly developed endotoxin specific chromogenic Limulus assay (endospecy test), which is devoid of factor G, did not react with any rabbit serum. But the beta-glucan measured by the conventional Limulus assay (toxicolor test), which contains the factor G, was elevated (from 10 pg/ml to 100 pg/ml) in all cases of rabbit model of system candidiasis. Serum D-arabinitol, measured by Sone's enzymatic fluorometric method, increased in all cases, but Cand-Tec (candida detection system by latex agglutination) showed only one positive case in five innoculated rabbits.

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.