Antibodies to Candida albicans germ tubes in two intensive care patients with invasive candidiasis.

Two cases of invasive candidiasis in intensive care patients are presented to illustrate the usefulness of detection of antibodies to Candida albicans germ tubes in the diagnosis of invasive candidiasis and in monitoring the efficacy of the antifungal treatment.

Detection of antibodies to Candida albicans germ tubes during experimental infections by different Candida species.

Identification and characterization of Candida albicans germ tube-specific antigens may be of relevance for the serodiagnosis of invasive candidiasis since they could be the basis for the development of new diagnostic tests. In this study, we have identified two antigens of 180 and >200 kDa in the cell wall of C. albicans germ tubes which are responsible for the induction of antibodies to C. albicans germ tubes. Antigens of similar molecular masses have been demonstrated in the cell walls of the Candida species C. stellatoidea, C. parapsilosis, C. guilliermondii, C. tropicalis, and C. krusei, but not C. glabrata. The kinetics of the antibody responses to C. albicans germ tubes were studied in rabbits infected with different Candida species. Although these antibodies were detected in rabbits infected with all Candida species except C. glabrata, the kinetics of the antibody responses to C. albicans germ tubes induced by the Candida species studied were different. Both the highest titer and the earliest response of antibodies to C. albicans germ tubes were observed in rabbits infected with either of the two serotypes of C. albicans used. However, the time needed to elicit the antibodies to C. albicans germ tubes can be reduced as the result of an anamnestic antibody response. The results presented in this study show that a test designed to detect antibodies against C. albicans germ tube antigens may be suitable for the diagnosis of infections caused by most of the medically important Candida species.

Detection of antibodies to Candida albicans germ tubes for diagnosis and therapeutic monitoring of invasive candidiasis in patients with hematologic malignancies.

We prospectively investigated the ability of detection of antibodies to Candida albicans germ tubes (CAGT) to diagnose invasive candidiasis in 95 consecutive admissions of 73 patients with hematologic disorders undergoing intensive chemotherapy. The episodes were divided into three groups according to clinical and microbiological diagnosis. Group 1 comprised eight admissions of eight patients with invasive candidiasis. Group 2 comprised 42 admissions of 34 patients without evidence of invasive candidiasis. Group 3 comprised the remaining 45 admissions of 37 patients with febrile episodes which were not diagnosed by microbiological culture. Antibodies to CAGT were detected in 87.5% of group 1 patients. Detection of antibodies to CAGT in patients with Candida fungemia was delayed somewhat relative to the time the blood culture was positive, but antibodies to CAGT were detected earlier than a diagnosis was made in patients with deep-tissue candidiasis. Sera from 2 admissions in group 2 and 12 admissions in group 3 revealed antibodies to CAGT. At a titer of > or = 1:20, detection of antibodies to CAGT had a sensitivity of 87.5%, specificity of 95.2%, positive predictive value of 77.8%, and negative predictive value of 97.6%. Antibodies to CAGT were usually detected before beginning of empiric antifungal therapy. Titers of antibodies to CAGT were maintained in most patients who died but declined and eventually disappeared in the patients who survived. Since antibodies to CAGT were detected in all patients with tissue-proven invasive candidiasis but negative by blood culture, detection of antibodies to CAGT complemented blood cultures for diagnosis and therapeutic monitoring of patients with hematologic malignancies and invasive candidiasis.

Variability in expression of antigens responsible for serotype specificity in Candida albicans.

The monoclonal antibody (mAb) B9E, which reacts with a cell wall surface determinant of Candida albicans serotype A, and a polyclonal monospecific antiserum against the antigen 6 (IF6) were used to investigate the expression of the antigens responsible for the serotype specificity in C. albicans under different growth conditions. By indirect immunofluorescence, both antibodies reacted with the cell wall surface of serotype A yeast cells and germ tubes grown in vitro but no reactivity was observed with serotype B yeast cells. In some cases, only a weak reactivity restricted to a zone close to the parent yeast cell was observed in serotype B germ tubes stained with mAb B9E. Both antibodies reacted strongly with yeast cells and germ tubes present in kidney abscesses from rabbits infected with both serotypes, but only serotype A yeast cells and germ tubes present in smears from patients with vulvovaginal candidiasis reacted with B9E and IF6 antibodies. The expression of antigens reactive with both antibodies was modulated by the pH of the environment in which the fungus was grown. Both antibodies showed a similar pattern of reactivity when studied with a spectrofluorometer. Serotype A yeast cells showed maximum reactivity when cells were grown on Sabouraud dextrose broth supplemented with yeast extract at pH 4.6. The lowest reactivity was observed in cells grown at pH 2.0. Conversely, the reactivity of serotype B yeast cells increased at alkaline pH values, the highest being in cells grown at pH values of 7.2 and 9.5.(ABSTRACT TRUNCATED AT 250 WORDS)

[Comparative study of 2 technics for the diagnosis of invasive candidiasis]. / Estudio comparativo de dos técnicas para el diagnóstico de la candidiasis invasiva.

BACKGROUND: We evaluate test for the detection of antibodies against-Candida albicans by indirect immunofluorescence (Candida Spot-IF, BioMérieux, Lyon, France and a test developed in our laboratory to detect anti-germ tube antibodies) comparatively for the serodiagnosis of invasive candidiasis. METHODS: A total of 121 sera from 62 patients were studied retrospectively. They were divided into two groups: group I included 71 sera from 28 patients with invasive candidiasis and group II, used as control, included 50 sera from 34 patients with non-invasive candidiasis or without evidence of infection by Candida. RESULTS: Eighty-two percent of group I samples presented anti-germ tube antibodies and 57% of the patients in this group were positive by the Candida Spot-IF test. Both techniques were negative in 5 patients. Five patients in group II showed false positive results by Candida Spot-IF and two of them presented anti-germ tube antibodies also. Both techniques presented a poor correlation (R2 = 0.159; p < 0.001). Detection of anti-germ tube antibodies showed a sensitivity of 82% and a specificity of 94% and Candida Spot-IF showed a sensitivity of 57% and a specificity of 85%. Detection of anti-germ tube antibodies in immunocompetent patients showed a sensitivity of 90% but it decreased to 62% in immunocompromised patients. With the Candida Spot-IF test the sensitivity was 70 and 25%, respectively. CONCLUSIONS: The detection of anti-germ tube antibodies was more sensitive and specific than detection of antibodies by the Candida Spot-IF test and it can be used for the serodiagnosis and follow up of patients with invasive candidiasis.

Detection of anti-Candida albicans IgE antibodies in vaginal washes from patients with acute vulvovaginal candidiasis.

Vaginal washes from 55 women were investigated by means of an ELISA method for the presence of IgE antibodies against Candida albicans. These antibodies were detected in 87.1% of patients with clinical acute vulvovaginal candidiasis (group I), 100% of patients with suspected vulvovaginal candidiasis but negative by microscopy and culture (group II), 0% of asymptomatic carriers (group III) and 33.3% of uninfected controls (group IV). Statistically significant differences were observed comparing groups I and II vs. groups III and IV. The highest IgE vaginal antibody titers were mostly at the expense of serotype A C. albicans strains, which represented 83.3% of the C. albicans isolates. Non-C. albicans species also showed very low IgE levels. No correlation between serum and vaginal IgE was found. Furthermore, a second determination of vaginal IgE levels was performed in 3 patients. A decrease in IgE levels concomitant to a decline in clinical symptoms was observed in all of them after treatment.

Identification of antigens reacting with anti-Candida albicans germ tube antibodies.

Anti-Candida albicans germ tube antibodies can be induced in rabbits immunized with different C. albicans extracts. Antigens responsible for the induction of those antibodies have molecular weights of approximately 230-250, 62, 43 and 41 kDa. These antigens are present in the cell wall of both C. albicans morphological forms, although their location seems to be different.

Vulvovaginal candidiasis refractory to treatment with fluconazole.

We present the case of an infertile patient, whose first attempt at IVF had to be postponed for 18 months due to a vulvovaginal yeast infection refractory to treatment. The main causative organism was a Candida glabrata strain resistant to all the imidazolic agents tested. The organism and the host's humoral status were studied in depth, looking for possible causes of the refractoriness to treatment.

[Microbiological study of 30 samples of heroin]. / Estudio microbiológico de 30 muestras de heroína.

In the present study, 30 samples of heroin from material seized by the police in Vizcaya from 7-1-1987 to 6-30-1988 were investigated. Bacillus spp were isolated in 19 samples (63.3%), coagulase negative staphylococci in 14 (46.6%), Aspergillus in 3 (10%) and S. aureus in one (3.33%). In addition, chemical analysis of the purity of heroin was carried out with gas chromatography. The purity of the samples ranged from 1.1% to 94.3%. No relation was found between the weight of the sample, its purity and its degree of microbiological contamination. In the microbiological study of 4 lemons used to dissolve the drug, Candida krusei was isolated from three samples, Aspergillus in two and Geotrichum in one.

Different antibody response against Candida albicans cell wall antigens in cervicovaginal secretions of patients with vulvovaginal candidiasis.

Vaginal washings from 118 women were investigated by means of immunofluorescence for the presence of antibodies against Candida albicans. A significantly (p less than 0.02) higher antibody titer was found in the samples from patients with clinically evident vulvovaginal candidiasis. Vaginal secretions from those patients with a positive culture for C. albicans were assayed by means of Western blotting. A distinct band pattern was found in the group of patients with a positive culture and the classical clinical picture of C. albicans vulvovaginitis.

Immune responses to yeast and mycelial forms of Candida albicans in intraperitoneally infected mice.

Candida albicans E-139 produced pure mycelial and yeast cultures in a low sulphate medium at different temperatures. The influence of the morphological phase, dose and viability of the fungi on the kinetic of delayed-type hypersensitivity (DTH) and anti-mycelial and anti-yeast antibodies have been studied in mice injected intraperitoneally. The mycelial form elicited higher DTH levels than the yeast phase. This effect seems to be related to its antigenic properties. The effect of dose on the immune response depends on the viability of the fungus. The mycelial cytoplasmic antigens were more effective than the yeast ones in detecting antibodies induced during the experiments, particularly during the later stages of the observation periods, suggesting that such antigens may be useful in the serodiagnosis of Candida infections.

Cellular and humoral immune responses to Candida albicans in subcutaneously infected mice.

Pure mycelial and yeast cultures of Candida albicans were produced in a low sulphate medium. Groups of mice were injected subcutaneously with increasing doses of viable or heat-killed mycelial or yeast cells and the kinetics of delayed-type hypersensitivity (DTH), anti-mycelial and anti-yeast antibodies were studied. Both the dose and the morphological phase of C. albicans showed an influence on the development of the DTH, but the viability is the factor which showed the highest influence on this reaction, since on the one hand mice infected with viable yeast or mycelial cells developed higher DTH levels than mice injected with heat killed cells, and on the other hand this factor seems to play an important role in the kinetics of DTH response. The enzyme-linked immunosorbent assay has been adapted to detect antibodies to yeast and mycelial phase cytoplasmic antigens of C. albicans. In contrast with the DTH reactions, neither dose, morphological phase nor viability played an important role on the antibody titer developed. However, the use of mycelial cytoplasmic antigens seems to be better than the yeasts to detect anti-Candida antibodies over the last days studied.

Comparison of three tests for measuring footpad swelling in the mouse.

Three tests, footpad thickness, footpad weight and footpad dye accumulation have been compared for measuring the local inflammatory reaction developed in the hind footpads of the mouse after injection of increasing doses of heat killed Candida albicans yeasts. The 3 tests showed high correlation indicating that any one of them may be used to evaluate such inflammatory reactions.

Lipid composition and the transition from yeast-like to chlamydospore cells of Pullularia pullulans.

The lipid composition of the fungus Pullularia pullulans has been investigated at different stages of the morphogenetic transition from yeast-like, through the so-called "large cells," to chlamydospores. The first 3 days of culture correspond to the period of exponential growth. There is a rapid consumption of glucose and ammonium, until the latter becomes exhausted, and a concomitant decrease of pH down to values of about 2. A decrease in fatty acid unsaturation takes place at this stage, together with an increase in the proportion of long-chain aldehydes. The period between days 3 and 6 is dominated by the large cells. They accumulate large amounts of triacylglycerols; phospholipids and free sterols are also synthesized in this period, suggesting de novo synthesis of membranes. Chlamydospores can be seen from the 6th day on. Simultaneously, a decrease in free sterols and phospholipids takes place, while saturated triacyglycerol production goes on. The lipid composition of chlamydospores suggests that these are resistance forms, induced by the hostile environmental conditions of the medium after the end of the exponential growth.