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Polyol concentrations were determined by selected-ion monitoring in 10 sample sets taken before dialysis and hourly for 4 h during dialysis. Predialysis concentrations (mumol/L) exceeding the upper limit of normal (mean + 2 SD; n = 33) were found for erythritol (25.4-59.0), threitol (11.5-46.7), and arabinitol (21.0-49.3) in all 10 cases; mannitol (2.7-62.0) in nine cases; and xylitol (0.7-1.3) in eight cases. Concentrations of adonitol, galactitol, and sorbitol were all within normal limits. During dialysis, the concentration of six polyols decreased by approximately 50%, but there were no significant changes for xylitol and adonitol. Erythritol, threitol, and arabinitol concentrations remained more than double the upper limit of normal in all patients after 4 h of dialysis. High residual concentrations were found for mannitol (seven cases) and xylitol (six cases). The results suggest fundamental differences in the homeostasis as well as the dialyzability of different polyols. The potential toxic significance of the high residual concentrations after a 4-h dialysis needs to be investigated.

We encountered a case of an 83-year-old patient with candida endocarditis. He had been diagnosed as having aortic regurgitation with moderately calcified aortic valve 5 years previously, and had received medication. He was admitted to our hospital because of pancreatic cancer. He had high fever from the time of his admission and antibiotics produced no effect. Candida albicans was detected in arterial blood culture. We also detected antibody against Candida albicans, and investigated serum mannan and the D-arabinitol creatinine ratio several times. We performed echo-cardiographic examination and recorded a vegetation at the aortic valve. Rising antibody titers against Candida albicans, mannan antigenemia and an elevated creatinine ratio were also observed. So we concluded that these examinations were also effective in the diagnosis of candida infection. Finally, this patient died of cerebral hemorrhage and was autopsied. Macroscopic findings showed mass-like vegetation involving the aortic valve, and microscopic findings showed candida organisms scattered within the vegetation.

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.

To differentiate increased arabinitol due to fungal (only D-arabinitol) and non-fungal origin, O-trifluoroacetyl derivatives of the enantiomers were separated using alpha-perpentylated cyclodextrin columns and measured by selected ion monitoring. Mean +/- S.D. D/L in normal serum: 1.40 +/- 0.42. D/L ratios greater than 2.24, defined as normal mean + 2S.D., were considered outside normal range. D/L was greater than 2.2 in 10 of 12 confirmed candidiasis cases with one false negative and one borderline. Renal dysfunction without candidiasis yielded normal D/L despite high arabinitol concentrations. D/L in normal urine was nearly identical to that in serum despite 60 times larger concentration. D/L ratios, determined by peak heights or areas, could be used without the need to determine concentrations.

Gas chromatography was used to identify D-arabinitol over time (5-6 times on the average) in the blood serum of 24 patients with fever of unclear etiology. The patients were in a state of cytostatic and/or cytostatic and radiation cytopenia. In 20 donors, D-arabinitol was identified once. In the majority of the donors, that indicator did not exceed 1 microgram/ml, amounting on the average to 0.7 +/- 0.3. In patients with invasive candidiasis, the concentration of D-arabinitol surpassed 1 microgram/ml, reaching 4.0-5.5 micrograms/ml in some patients. In patients colonized with Candida, that indicator also exceeded 1 microgram/ml, not reaching, however, such high values as those seen in invasive candidiasis. Identification of the D-arabinitol level reflects the total activity of the fungi of the Candida genus contaminating the patients' mucous membranes at the moment of investigation irrespective of the process site, whereas monitoring allows one to follow tendencies of that activity and to correct therapy.

This study was carried out on two groups of healthy young subjects. One group (n = 8) was given a single oral dose of galactose (0.5 g/kg body weight), and a single measurement of blood galactose was made 40 min later. A second group (n = 16) was given a daily supplement of 0.5 g/kg galactose for 15 days, and blood galactose and galactitol were measured. On the first day of the test period, some subjects seemed to tolerate galactose less well than others: galactitol appeared in their plasmas and could be related to a significantly higher galactosaemia than that of subjects without detectable galactitol in the plasma. However, after 15 days of galactose intake, the less galactose-tolerant subjects appeared to have adapted, as indicated by the significant decrease in the blood galactose and the disappearance of galactitol. No change was found in the galactose-tolerant subjects. No significant difference was found between males and females.

Erythrocyte deformability measured as filtration index is clearly diminished in diabetics, thus possibly contributing to diabetes-associated microvascular complications. Moreover, the erythrocyte sorbitol level in IDD is clearly higher than that of non-diabetics, suggesting an alteration in the polyol pathway as possible determinant of diabetes-associated complications. Following this line of research, intracellular sorbitol as well as glucose, inositol, galactitol, mannitol and 2,3-diphosphoglycerate have been studied in 21 diabetics and in 14 controls matched for age and sex. In addition to confirming the high levels of intraerythrocytic glucose and sorbitol in diabetic subjects, statistically significant correlations have been demonstrated between sorbitol and filtration index, between plasma glucose, intracellular glucose level and glycosylated hemoglobin, suggesting a relationship between metabolic control and hemorheologic alterations in diabetes.

Three proposed quantitative markers for candidiasis, arabinitol, mannose, and mannan in serum, are compared in 50 normal blood donors and 38 high-risk patients, 23 with and 15 without invasive candidiasis. Arabinitol concentrations in serum, the arabinitol/creatinine ratio, and mannose concentrations in serum were significantly greater in the 15 patients without candidiasis than in the normal blood donors (P less than 0.05). The sensitivities and specificities were 26 and 87% for arabinitol, 13 and 93% for the arabinitol/creatinine ratio, and 39 and 87% for mannose. On the other hand, mannan concentrations in serum were less than 1 ng/ml in normal blood donors and patients without candidiasis (P = 0.344), and the sensitivity and specificity were 65 and 100%, respectively. Of 23 patients with proven or probable candidiasis, 16 had mannan levels in serum greater than the mean + 2 standard deviations (0.46 ng/ml) for the 15 controls. In 16 patients with invasive candidiasis and positive blood cultures for the Candida spp., only 13 had elevated levels of at least one of the three markers. The arabinitol/creatinine ratio, the mannose level, and the mannan level became elevated an average of 4 days before, 1 day before, and on the same day that the blood cultures were drawn, respectively. Conversely, mannan was detected in the sera of six of seven patients with invasive candidiasis and negative blood cultures. We conclude that the best approach to diagnosing invasive candidiasis involves obtaining blood cultures and carrying out serial assays for mannan in serum.

We describe a method for comparing plasma samples from healthy subjects and from chronic uremic patients before and after dialysis. It was used to determine the nature of those metabolites that appear to characterize the uremic state. Preliminary fractionation of the metabolites by gel chromatography was followed by removal of the aqueous effluent by lyophilization and preparation of volatile trimethylsilyl derivatives, which were then examined by gas-liquid chromatography. Gas-liquid chromatography/mass spectrometry was used to characterize and identify individual metabolites. Gas-liquid chromatographic patterns of plasma from healthy and uremic subjects differ markedly, more so than do individual plasma samples within the same class of subjects. Concentrations of many metabolites are increased in uremia, but after dialysis of the patient's blood, the concentrations become about the same as those in healthy plasma. We have observed some 150-200 metabolites in each category of plasma. We have tentatively identified about a tenth of the compounds that appear to be specific to or increased in uremia, including lactic acid, glycerol, erythritol, erythronic acid, 2-deoxy erythro pentonic acid, arabinitolarabinonic acid, inositol, and lactose. Some of these are present in concentrations greater than 20 mg/liter and have not been previously reported as occurring in the uremic state.

A technique was developed for separating total serum pentitols into individual arabinitol, adonitol and xylitol and determining their relevance for the diagnosis of disseminated candidiasis. Pentitols were separated as trimethylsilyl derivatives on two 25 m long, bonded methyl silicone columns with a 0.32 mm i.d., and quantified by selected ion monitoring of their protonated molecular ions obtained in chemical ionization. The 173 samples studied were divided into culture-positive, culture-negative, and no-culture groups. Twelve percent of all samples were false positives by the total pentitols method due to increased adonitol and/or xylitol. The continued use of the total pentitols method is, nevertheless, recommended because of its convenience; however, samples with increased total pentitols (and normal creatinine) should be reanalyzed for individual pentitols. Increased arabinitol and normal creatinine are indicative of candidiasis even when blood cultures are negative.

We measured the Candida metabolite D-arabinitol and its enantiomer L-arabinitol in 42 serum samples from 33 patients with sarcoidosis and compared the results with those from 27 healthy adults and 4 patients with candidiasis. The D- and L-arabinitol concentrations and the D- and L-arabinitol/creatinine ratios did not differ significantly in the sarcoidosis patients and the controls; the D-arabinitol concentrations and the D-arabinitol/creatinine ratios were much higher in the patients with candidiasis. Among the patients with sarcoidosis, the D- and L-arabinitol levels in the steroid recipients did not differ significantly from those in patients not receiving steroids. Higher D-arabinitol/creatinine ratios were associated with roentgenographic evidence of pulmonary fibrosis and low forced vital capacities, but not with disease activity as determined by the proportion of lymphocytes to total nucleated cells in bronchoalveolar lavage fluid or the CD4/CD8 ratio in bronchoalveolar lymphocytes. We conclude that neither sarcoidosis nor corticosteroid treatment is associated with high levels of D-arabinitol in serum.

A method is described for the simultaneous quantitation of D-arabinitol and D-mannose in serum by gas-liquid chromatography as an aid for the diagnosis of disseminated candidiasis. Both variables were observed as per-O-acetylated aldononitrile derivatives in each chromatographic run of sera from immunosuppressed rabbits experimentally infected with Candida albicans 3181A.

Serum arabinitol concentrations and arabinitol/creatinine ratios were determined in 25 cancer patients with invasive candidiasis, 73 severely ill cancer patients who did not have invasive candidiasis, and 15 uninfected patients with chronic renal failure. Elevated arabinitol concentrations were found in patients with renal failure and invasive candidiasis. Serum arabinitol concentrations exceeded 1.19 micrograms/ml in 13 of 18 patients with invasive candidiasis who were studied when renal function was normal and in three of 52 control patients. Among patients with renal failure, 10 of 14 with invasive candidiasis but only four of 36 control patients had serum arabinitol concentrations of greater than 5.85 micrograms/ml. Serum arabinitol and creatinine concentrations were strongly correlated. The arabinitol/ creatinine ratio exceeded 1.5 in 16 of 25 patients with invasive candidiasis but in only three of 88 control patients. Increased serum arabinitol concentrations appear to reflect increased production of arabinitol by yeast in individuals with invasive candidiasis.

Two major metabolic perturbations, increased polyol (sorbitol) pathway activity and reduced tissue myo-inositol content, are induced in peripheral nerve by hyperglycemia. Although they are commonly invoked as alternative biochemical pathogenetic mechanisms for diabetic neuropathy, their possible interrelationship has never been adequately explored. Therefore, we studied the effect of polyol pathway blockade with sorbinil, a specific inhibitor of aldose reductase, on nerve myo-inositol content in acutely streptozotocin-diabetic rats. Sorbinil administration completely prevented the fall in nerve myo-inositol, thereby implicating increased polyol pathway activity as a likely factor in the fall in nerve myo-inositol content in experimental diabetes.

Arabinitol concentrations were determined in 157 serum samples from 95 patients with suspected invasive candidosis and in 10 serum samples from healthy laboratory workers. Fifty eight of the 95 patients, subsequently diagnosed as not having invasive candidosis had concentrations of arabinitol below 1.2 micrograms/ml (mean 0.59 (SD) 0.26). Sera from the healthy laboratory workers gave similar results (mean 0.55 (0.05]. Concentrations above the normal range were found in 18 of the 19 cases of confirmed or probable invasive candidosis and in seven of eight patients with infected intravenous lines or cannulas and clinical evidence of systemic infection. Raised concentrations were also seen in 10 other patients, including nine with renal failure who did not have invasive infections. Multiple serum samples obtained from 33 patients showed that sequential estimations were of value for diagnosing a developing infection. Despite some difficulties of interpretation the technique is rapid and specific and is suitable for use in the diagnostic laboratory of a larger general hospital.

D-Arabinitol has been found in the serum of patients with candidiasis in an incidence varying from 38 to 82%. While screening serum by gas chromatography for the presence of this sugar, we observed elevated concentrations in several patients with sarcoidosis. In an attempt to determine the significance of this chance observation, we tested serum from additional patients with sarcoidosis along with serum from patients with other clinical conditions known to be associated with elevated D-arabinitol levels. Of 53 patients with sarcoidosis, 27 (51%) had elevated concentrations of this compound. Only one of these patients had decreased renal function (creatinine, 2.5 mg/dl). We were unable to correlate elevated values with extent of the disease. Although the significance of this finding is not clear, it may represent a clue to the pathogenesis of sarcoidosis.

The development of a selected ion monitoring assay is described for the analysis of polyols as their per-acetyl derivatives, using L-iditol as an internal standard. Concentrations of mannitol, galactitol, sorbitol and inositol have been determined in the serum, urine and amniotic fluid from women during the second trimester of uncomplicated pregnancies. Two samples of amniotic fluid from galactosaemic pregnancies showed elevated levels of galactitol, 8.1 and 7.7 mu mol l-1 compared with normal concentrations of 0.46 +/- 0.26 mu mol l-1, whereas a normal homozygous pregnancy of heterozygous parents showed normal levels.

A high-performance liquid chromatographic method is described for measuring submicrogram quantities of dianhydrogalactitol, a promising anti-neoplastic agent, in plasma. The drug is derivatized directly in plasma with sodium diethyldithiocarbamate to form a bis(dithiocarbamoyl) ester which absorbs UV light at 254 nm (am 17,000). The derivatized product is then extracted quantitatively into chloroform and separated by normal phase chromatography (muBondpak CN column). Dianhydrogalactitol concentration below 50 ng/ml of plasma can be detected in the eluent.

Human platelet membrane glycoproteins IIb (GPIIb) and IIIa (GPIIIa), which have been proposed to be subunits of a receptor for fibrinogen, were purified from Triton X-100-solubilized platelet membranes by affinity chromatography on a concanavalin A (Con A)-Sepharose column followed by preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Compositional analyses of the purified glycoproteins showed that GPIIb and GPIIIa contain 15% and 18% carbohydrate by weight, respectively, which consists of galactose, mannose, glucosamine, fucose, and sialic acid. This suggested that these glycoproteins contained N-linked carbohydrate chains. The carbohydrate chains were released from each glycoprotein by hydrazinolysis and then fractionated by ion-exchange chromatography on a Mono Q column. From each glycoprotein, mono-, di-, and trisialylated and neutral oligosaccharide fractions were obtained. The structures of these oligosaccharides were investigated by means of compositional and methylation analyses and digestion by exoglycosidase, and their reactivities to immobilized lectins were also examined. The neutral oligosaccharides, which comprised about 14% of the total oligosaccharides released from GPIIb and about 52% of that from GPIIIa, were found to be of the high mannose-type, in that they contained 5 or 6 mannose residues. On the other hand, a major part of the acidic oligosaccharides was found to consist of typical bi- and triantennary complex-type sugar chains, and much smaller amounts of tetraantennary complex-type sugar chains, and complex-type sugar chains with a fucosyl residue at a N-acetylglucosamine residue in the peripheral portion or a bisecting N-acetylglucosamine at a beta-mannosyl residue in the core portion were also detected. In conclusion, we found that GPIIb contained mainly complex-type sugar chains, whereas high mannose-type sugar chains were the predominant carbohydrate units in GPIIIa, and that the detected differences in the carbohydrate moieties of GPIIb and GPIIIa were quantitative but not qualitative.

Five polyols, arabinitol, anhydroglucitol, mannitol, sorbitol and myoinositol, normally present in the cerebrospinal fluid (CSF), were studied. Quantitative gas-liquid chromatographic analysis of 211 CSF and 112 plasma samples indicated significantly altered concentrations in several clinical conditions. All five polyols were decreased in the CSF of patients suffering from meningitis, cerebral atrophy, sepsis, and in patients receiving intrathecal cytostate therapy. Equilibration between plasma and CSF may explain the changes in sepsis and meningitis, while decreased total number of functioning cells may cause the decrease in cerebral atrophy. Intrathecal cytostates seem to have a destroying effect on the cell metabolism of the central nervous system. Renal failure causes accumulation of polyols in the plasma. Alterations in the metabolism of sorbitol, myoinositol and anhydroglucitol seem to be present in diabetes. The plasma concentration of anhydroglucitol is decreased in renal failure.

Seven polyols, erythritol, arabinitol, anhydroflucitol, mannitol, sorbitol, myoinositol and possibly ribitol were identified in human cerebrospinal fluid by means of gas-liquid chromatography and mass spectrometry. Quantitative data were obtained for five polyols, arabinitol, anhydroglucitol, mannitol, sorbitol and myoinositol, by screening of 205 CSF samples. These five polyols represented 90-95 per cent of the polyol-concentration which was 340 +/- 105 mumol/1 in the total series. The concentration of polyols in the CSF was two times higher than that in the plasma (148 +/- 30 mumol/1), where only anhydroglucitol and myoinositol could be quantitated. The variations noted were not associated with age, sex or the plasma concentrations of polyols. The polyols of the CSF most likely originate from brain tissue and/or spinal cord since penetration from the plasma against a gradient seems unlikely.

We used gas chromatography-chemical ionization mass spectrometry with selected ion monitoring of the (M-59)+ ions to determine polyols (as their peracetyl derivatives) in serum. The internal standard was 2-deoxygalactitol. Mean (and SD) polyol concentrations (mg/L) in 33 normal sera were: erythritol 0.45 (0.14), threitol 0.20 (0.06), adonitol 0.06 (0.02), arabinitol 0.37 (0.12), xylitol 0.05 (0.02), mannitol 0.41 (0.45), galactitol 0.15 (0.11), sorbitol 0.16 (0.11). Arabinitol determined in the same 33 normal sera by trimethylsilylation was 0.39 (0.13) mg/L. In 32 samples from cancer patients with normal creatinine, all polyol concentrations were in the normal range except for seven increased erythritol and one increased threitol concentrations. In all six patients with renal dysfunction we found increased erythritol and arabinitol, and increased threitol and mannitol in four of the six. Initial results showed that only arabinitol concentrations increased in invasive candidiasis.

Gas-liquid chromatography was used to quantitate the arabinitol concentration in the sera of patients with candidiasis and in that of control patients. Serum arabinitol was elevated in 59% (n = 34) of patients with Candida sepsis, in 39% (n = 38) with Candida colonization, in 14% (n = 62) with bacterial sepsis, and in 0% (n = 11) of normal persons. The above patients were subsequently divided on the basis of renal function. Of those with decreased renal function, serum arabinitol was elevated in 89, 92, and 50% of patients with Candida sepsis, Candida colonization, and bacterial sepsis, respectively. Of those with normal renal function, serum arabinitol was elevated in only 23 and 14% of patients with Candida sepsis and Candida colonization, respectively. When serum arabinitol/creatine ratios were calculated for patients with both increased arabinitol and increased creatinine, elevated ratios were obtained in 69, 36, and 0% of patients with Candida sepsis, Candida colonization, and bacterial sepsis, respectively.

The kinetic equations describing transport through a pore that has a binding site and that undergoes a conformational change are identical to those of a carrier model. Therefore, in order to distinguish between the two models it is necessary to test specific predictions based on detailed mechanistic models. A pore model is described in which the substrate (glucose) is able to reach the single binding site only from the outside when the pore is in conformation I and only from the inside when it is conformation II. On the basis of this model it is predicted that solutes which do not have any specific affinity for the binding site should still have a finite permeability via the glucose transport system if they are the same size or smaller than glucose. This permeability should be proportional to the volume of distribution of the solute in the pore and should therefore decrease with increasing molecular size. A geometric pore volume can be estimated from this size dependence. In order to test these predictions, the glucose-dependent permeability of a series of 4-carbon (erythritol), 5-carbon (D-arabitol, L-arabitol and xylitol) and 6-carbon (D-mannitol, D-sorbitol and myo-inositol) polyols was measured. The permeability of all the polyols is decreased by the presence of glucose and the KI of this "inhibitable" component is similar to that D-sorbose, suggesting that this component is associated with the glucose transport system. Since these observations could be explained entirely in terms of a specific affinity for a carrier binding site, they do not exclude a carrier mechanism. However, as predicted for the pore model, this "inhibitable" permeability decreased with increasing molecular size and the calculated geometric pore volume was of a size that would be expected for a cell membrane pore.

We describe a gas chromatographic method for measuring submicrogram quantities of dianhydrogalactitol, a promising antineoplastic agent (currently undergoing clinical trials in humans), in plasma. The drug is first extracted from blood plasma by saturating the aqueous phase with solid potassium carbonate and extracting with isopropanol/chloroform (9/1 by vol). It is then converted to the corresponding n-butaneboronic ester by reaction at room temperature with butaneboronic acid and chromatographed on an SE-30 (3%) column, with flame ionization detection. Practicality of the method for monitoring drug distribution was demonstrated by administering dianhydrogalactitol in therapeutic doses to a dog and monitoring its concentrations in blood for the next 2 h.

Cerebrospinal fluid (CSF) or CSF and plasma levels of sorbitol, 1,5-anhydroglucitol and myoinositol of diabetic and non-diabetic patients with normal kidney function and of diabetic and non-diabetic patients with impaired kidney function were measured by gas-liquid chromatography. The CSF sorbitol level correlated with the plasma glucose level (p less than or equal to 0.05) in diabetic patients with normal kidney function, having received insulin for less than 12 months. The correlation between CSF sorbitol and plasma glucose levels in patients not dependent on insulin was not significant. Sorbitol was not detected in the plasma. The highest sorbitol levels in CSF were seen in insulin-dependent diabetic patients with impaired kidney function. No rise was seen in non-diabetic uremia. 1,5-anhydroglucitol, normally present in plasma, was absent from CSF and plasma in diabetic patients receiving insulin. In non-diabetic uremic patients, 1,5-anhydroglucitol levels in CSF and plasma were lower than in healthy subjects, but htere was no correlation with plasma glucose levels. The myoinositol level was higher in CSF than in the plasma of both non-diabetic and diabetic patients with normal kidney function. Both plasma and CSF levels were significantly (p less than 0.001) elevated in diabetic as well as in non-diabetic uremic patients, the plasma myoinositol increasing relatively more than the CSF levels. The elevation of plasma myoinositol correlated with the elevation of plasma creatinine and thus also with the impairment of kidney function. Plasma and CSF myoinositol levels were not influenced by the plasma glucose level.

Concentrations of arabinitol, mannose, and mannan in serum have independently been reported to be elevated in patients with invasive candidiasis. These three marker substances were compared in a rabbit model. Twelve rabbits, immunosuppressed with cortisone, were infected intravenously with Candida albicans 3181A. Six uninfected control animals also received cortisone, and four rabbits were neither infected nor immunosuppressed. Blood samples, drawn from 2 days before to 14 days after infection, were assayed for serum mannan by sandwich enzyme immunoassay, antibodies to mannan by indirect enzyme immunoassay, arabinitol and mannose by gas-liquid chromatography, and serum creatinine. Serum mannan, negative before infection, peaked in all infected animals 4 days after infection (mean, 18 ng/ml) and decreased thereafter. Significant increases (2 standard deviations greater than mean in normals) in arabinitol, the arabinitol/creatinine ratio, and mannose were found in 12, 8, and 12 of the infected rabbits, respectively, but also in all 6 uninfected animals receiving cortisone. Only serum mannan was specific in this immunosuppressed rabbit model.

Arabinitol is a pentitol generated in large quantitites by several species of Candida, including Candida albicans. The level of arabinitol in the sera of infected animals and humans was determined by gas-liquid chromatography of an acetone extract of the serum. Experimentally infected mice with pyelonephritis due to C. albicans had elevated levels of arabinitol; rabbits with pyelonephritis did not have elevated levels, nor did rabbits with catheter-induce cystitis, but rabbits with endocarditis developed elevated levels of arabinitol shortly before death. A prospective study in patients clinically suspected of having invasive candidiasis failed to show elevated levels of arabinitol in most. Mice and patients not colonized or infected with yeasts but with renal failure had high serum levels of arabinitol. The data indicate that an elevated level of arabinitol in the serum of a patient without renal disease is suggestive of invasive candidiasis, but normal serum levels do not contradict the diagnosis.

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.

This report describes an application of liquid chromatography to the determination of sorbitol in red blood cells. The chromatograph employed in the present study was made up of sub- and main-separation systems and a detector portion. The sub-separation system was for concentration of polyols and involved two small columns, each containing the same anion exchange resin. The first was a tiny column which, in borate form, served as the concentrator of polyols and sugars charged in a large volume, while the second, in acetate form, separated the carbohydrates from the borate. The main system was for the fine separation of each carbohydrate and employed cation exchange columns. The detector part utilized a flow fluorometric method comprising two successive reactions: periodate oxidation followed by the Hantzsch reaction. The resulting whole chromatographic system was applied to the determination of sorbitol in red blood cells obtained from normal rats and rats made diabetic by the administration of streptozotocin; a part of the latter group had also received an aldose reductase inhibitor. Our results supported the concepts that a prolonged duration of high blood glucose level induces an elevated level of sorbitol inside red blood cells and that aldose reductase inhibitors are effective in reducing this level.

A multi-dimensional gas chromatographic method was developed to measure the Candida metabolite D-arabinitol enantioselectively in human serum. The heptafluorobutyrate derivatives of D-arabinitol, L-arabinitol and ribitol (internal standard) were separated from other serum constituents with a 60 m X 0.32 mm fused-silica SPB-5 precolumn, and (after intermediate cold trapping) they were separated from each other with a 25 m x 0.25 mm fused-silica column coated with a new bonded chiral phase. Replicate analyses of spiked human sera showed that D-arabinitol could be quantified accurately and precisely. The D- and L-arabinitol concentrations in 24 normal adult sera were 0.20 +/- 0.053 and 0.11 +/- 0.040 mu/ml, respectively, and the D- and L-arabinitol/creatinine ratios were 0.023 +/- 0.011 and 0.012 +/- 0.0051, respectively (mean +/- S.D.). In a patient with Candida albicans fungemia, the D-arabinitol/creatinine ratios rose early during infection and fell with successful treatment, whereas L-arabinitol/creatinine ratios did not change significantly. This enantioselective analytical method is more practical than earlier ones; it should facilitate further investigation of D-arabinitol as a diagnostic marker for candidiasis.

A new method was used to measure D-arabinitol enantioselectively in the sera of 27 healthy adults and four patients with candidiasis. Arabinitol was measured by gas chromatography in serum that was treated with and without the Klebsiella pneumoniae enzyme D-arabinitol dehydrogenase, lactic dehydrogenase, NAD, and sodium pyruvate. Since enzyme treatment removed 98% of 0 to 20 micrograms of D-arabinitol per ml and none of 0 to 20 micrograms of L-arabinitol per ml from spiked sera, D-arabinitol could be determined from the difference in the treated and untreated samples. The concentrations of D- and L-arabinitol in serum from normal subjects were 0.22 +/- 0.052 and 0.16 +/- 0.055 micrograms/ml, respectively, and their D-arabinitol/creatinine and L-arabinitol/creatinine ratios were 0.024 +/- 0.0089 and 0.017 +/- 0.0053 (all means +/- standard deviations). The infected patients all had markedly elevated serum D-arabinitol levels, but their L-arabinitol levels were either normal or proportionately much lower. The excess arabinitol in the sera of individuals with candidiasis is D-arabinitol, and use of enantioselective analytical methods should result in improved ability to diagnose and estimate the severity of candidiasis.

To determine the value of serum arabinitol concentrations in clinical practice, we identified all patients at the University of Utah Medical Center for whom a serum arabinitol determination had been requested by the attending physician or housestaff to assist in the management of candidiasis. The patient population was divided into three categories on the basis of clinical and pathological findings: superficial candidiasis, possible deep, invasive candidiasis, and definite, deep invasive candidiasis. Abnormal renal function was associated with elevated concentrations of serum arabinitol in proportion to the degree of renal dysfunction. Both the serum arabinitol concentration and the arabinitol/creatinine ratio were increased in the combined patient population with candidiasis relative to normal uninfected controls (p = 0.06 and 0.001, respectively). However, neither of these tests reliably distinguished patients with invasive candidiasis from those with only superficial candidal disease.

The levels of galactose and galactitol in the sera of 6 young adults after ingestion of 0.25 g/kg of galactose alone or with the same quantity of glucose were studied. The results showed that: glucose decreased significantly the galactosemia and galactitolemia observed after ingestion of galactose alone; repeated consumption on 4 consecutive days of galactose alone induced an increase in galactosemia, and more significantly in galactitolemia. The addition of glucose to galactose in the same conditions abolished these effects.

D-Arabinitol was identified as a major metabolite of Candida species in human subjects. Gas-liquid chromatography was used to measure the concentration of D-arabinitol in serum. The study included subjects who were healthy and cancer patients who had proven invasive candidiasis or were colonized with Candida. D-Arabinitol concentrations greater than 1.0 microgram per milliliter were found in serum from patients with invasive infection. This technique may prove valuable in the diagnosis of invasive candidiasis.

Because routine analytical methods cannot differentiate D- from L-arabinitol, a combined microbiological and gas chromatographic method was developed to study the stereoisomeric configuration of the arabinitol in humans and rats with invasive candidiasis. D-Arabinitol was defined as the difference between arabinitol concentrations measured with and without incubation with 5.0 X 10(5) blastospores of Candida tropicalis strain CT 12 at 37 C for 24 hr. The yeast consumed at least 95% of the D-arabinitol and none of the L-arabinitol added to normal serum and urine. D-Arabinitol as a fraction of D,L-arabinitol was 0.43 +/- 0.15 (mean +/- SD) in the urine of 10 normal humans, 0.82 +/- 0.12 in the serum or urine of five patients with cancer and invasive candidiasis (P less than .001), and 1.0 in the kidneys of rats with candidiasis. Because most or all of the excess arabinitol in body fluids or tissues in candidiasis was the D isomer, which is produced by fungal metabolism, stereospecific quantitation of arabinitol should improve the sensitivity of this approach to diagnosis of candidiasis.

We describe a new, simple, fluorometric assay for D-arabinitol in serum. The method is based on oxidation of D-arabinitol by D-arabinitol dehydrogenase (EC 1.1.1.11), with the concomitant reduction of NAD. The initial rate of NAD reduction, which is proportional to the D-arabinitol content of serum, can be measured with a recording spectrofluorometer. Sensitivity, specificity, recovery and reproducibility experiments gave satisfactory results. The proposed method is suitable for clinical use, and may be helpful in the diagnosis of invasive candidiasis.

Erythrocyte sorbitol level has previously been used as a measure of the efficacy of aldose reductase inhibitors, but its value is limited by fluctuations related to variations in blood glucose concentration. The aim of the study was to compare sorbitol content with the ability to accumulate galactitol during ex vivo incubation with galactose, of erythrocytes taken from diabetic patients following administration of a single 600 mg dose of the aldose reductase inhibitor, ponalrestat. Twelve patients were studied in a placebo-controlled crossover trial. Blood glucose levels were not statistically different during the placebo and ponalrestat treatment periods except at 1 h after the dose was taken (10.6 +/- 6.7 vs 7.7 +/- 4.6 mmol l-1 (+/- SD), p less than 0.05). Ponalrestat reduced erythrocyte sorbitol concentrations compared with placebo at 3, 5 and 7 h (0.82 +/- 0.36, 0.69 +/- 0.23, and 0.83 +/- 0.35 mg l-1 vs 1.79 +/- 0.67, 1.68 +/- 0.65, and 1.57 +/- 0.59 mg l-1 respectively, p less than 0.005) and 24 h post-dose (1.57 + 0.45 vs 2.01 + 0.73 mg l-1, p less than 0.05). Ponalrestat also reduced erythrocyte galactitol accumulation at 3, 5 and 24 h post-dose from 5.53 +/- 2.41, 5.43 +/- 1.89, and 5.42 +/- 1.96 mg l-1 2-h-1 to 1.47 +/- 0.30, 1.76 +/- 0.41, and 4.12 +/- 0.72 mg l-1 2-h-1 respectively, p less than 0.01. Galactitol accumulation rate appeared to be a less variable parameter than erythrocyte sorbitol and was not influenced by fluctuations in blood glucose.(ABSTRACT TRUNCATED AT 250 WORDS)