Elevated mannose levels detected by gas-liquid chromatography in hydrolysates of serum from rats and humans with candidiasis

Abstract

We have developed a gas-liquid chromatographic method for identification of mannose in serum hydrolysates by utilizing peracetylated aldononitrile derivatives. Experimentally infected rats and human subjects with candidiasis were studied. Peaks in unknown samples were identified by co-chromatography of reference carbohydrates. Inositol was used as an internal standard. Mannose was identified in hydrolysates of normal rat (391.85 ± 66.18 μg/ml) and human (297.87 ± 77.81 μg/ml) sera. Significantly increased concentrations of mannose (>526.21 μg/ml) were demonstrated in hydrolysates of sera from 26 of 36 (72%) experimentally infected rats tested 1 or more days after onset of infection. Significant increases (>453.49 μg/ml) were also seen in humans with localized (6/15), transient (2/2), and disseminated (5/7) candidiasis. The concentrations were highest in patients with candidemia occurring either transiently or as part of disseminated infection. The concentrations in patients with localized candidiasis were lower but were still significantly greater than control. These data suggest that changes in mannose concentration, as measured, may serve as markers of candidiasis. The amount of mannose present may be in part a function of the extent of the infection.