Activity of the renin-angiotensin-aldosterone system in euglycemic type I diabetic patients on intensive insulin treatment without diabetic neuropathy

The yeast Candida albicans coaggregates with a variety of streptococcal species, an interaction that may promote oral colonization by yeast cells. C. albicans and Candida tropicalis are the yeasts most frequently isolated from the human oral cavity and our data demonstrate that both these species bind to Streptococcus gordonii NCTC 7869 while two other Candida species (Candida krusei and Candida kefyr) do not. Adherence of C. albicans was greatest when the yeast had been grown at 30 degrees C to mid-exponential growth phase. For 21 strains of C. albicans there was a positive correlation between the ability to adhere to S. gordonii and adherence to experimental salivary pellicle. Whole saliva either stimulated or slightly inhibited adherence of C. albicans to S. gordonii depending on the streptococcal growth conditions. The results suggest that the major salivary adhesins and coaggregation adhesins of C. albicans are co-expressed.     

Mycotic vulvovaginitis

Vulvovaginitis is the most common clinical manifestation of fungal infections causing human mycoses; the incidence occurs in 10% of women, during pregnancy the incidence achieves 30% of cases. Candida albicans has resulted to be the most commonly isolated agent in patients with fungemia. In fact, Candida appears to be the species recovered in as many as 90% of cases. They are mainly the sexual activity, hormonal contraception and several pathologies such as diabetes mellitus and thyroiditis responsible for the pathogenesis of infection. The first symptom of this infection is usually pruritus associated to leukorrhea, dyspareunia and vulvovaginal irritation. Antifungal therapy may be required in more severe cases of vulvovaginal candidiasis. Candida species can be identified on isolation culture media including agar and on direct examination. Diagnosis can also be made through san immunologic examination. However, the authors confirm that the risk factors together with a correct diagnosis of the Candida etiological agent in the different species (albicans, glabrata, tropicalis, krusei) should be accurately investigated in order to give the correct therapeutical approach.     

In vitro susceptibility of clinical yeast isolates to fluconazole and terconazole

OBJECTIVE: Fifty clinical yeast isolates, representing equally Candida albicans, Candida krusei, Candida parapsilosis, Candida tropicalis, and Torulopsis glabrata, were tested in vitro for their susceptibility to terconazole and fluconazole. STUDY DESIGN: The minimal inhibitory concentrations of terconazole and fluconazole were determined by use of a proposed standardized broth macrodilution assay. Also, the response of selected yeast isolates to 25 micrograms of either drug was measured by agarose disk diffusion experiments. RESULTS: For all species the minimum inhibitory concentrations for terconazole were significantly lower than those for fluconazole (p < 0.05). In fact, for each individual isolate the minimum inhibitory concentration of terconazole was consistently lower than that of fluconazole. Differences in the geometric mean of terconazole and fluconazole minimum inhibitory concentrations were largest among C. krusei and T. glabrata, followed by C. parapsilosis, C. tropicalis, and C. albicans, in order of decreasing difference. Disk diffusion experiments suggested that terconazole is a more effective fungistatic agent than fluconazole is. CONCLUSION: Terconazole may be more effective than fluconazole against yeast species other than C. albicans.     

Stable phenotypic resistance of Candida species to amphotericin B conferred by preexposure to subinhibitory levels of azoles

The fungicidal activity of amphotericin B (AmB) was quantitated for several Candida species. Candida albicans and C. tropicalis were consistently susceptible to AmB, with less than 1% survivors after 6 h of exposure to AmB. C. parapsilosis and variants of C. lusitaniae and C. guilliermondii were the most resistant, demonstrating 50 to 90% survivors in this time period and as high as 1% survival after a 24-h exposure time. All Candida species were killed (<1% survivors) after 24 h of exposure to AmB. In contrast, overnight exposure to either fluconazole or itraconazole resulted in pronounced increases in resistance to subsequent exposures to AmB. Most dramatically, C. albicans was able to grow in AmB cultures after azole preexposure. Several other Candida species did not grow in AmB but showed little or no reduction in viability after up to 24 h in AmB. Depending on the growth conditions, Candida cells preexposed to azoles may retain AmB resistance for days after the azoles have been removed. If this in vitro antagonism applies to the clinical setting, treatment of patients with certain antifungal combinations may not be beneficial. The ability of some Candida isolates to survive transient exposures to AmB was not reflected in the in vitro susceptibility changes as measured by standard MIC assays. This finding should be considered in studies attempting to correlate patient outcome with in vitro susceptibilities of clinical fungal isolates. Patients who fail to respond to AmB may be infected with isolates that are classified as susceptible by standard in vitro assays but that may be resistant to transient antifungal exposures which may be more relevant in the clinical setting.     

A microbiologic and ultrastructural investigation of germ-tube formation by oral strains of Candida tropicalis

Presumptive germ tube-positive and -negative Candida tropicalis strains have been obtained from both normal children and patients who have candidiasis. Examination of these strains by conventional microbiologic tests confirmed them to be C. tropicalis. Ultrastructural examination of the filaments produced by the positive strains revealed two types: true germ tubes and those with basally constricted cytoplasm. A fluctuation analysis of the positive strains showed two subgroups: germ tube-positive and -negative. It is suggested that C. tropicalis strains may be divided into germ tube-positive and -negative strains, and that germ-tube formation must therefore not be used as a sole criterion for identification of C. albicans.     

Liver injury in abdominal trauma. Review of the literature and personal observations

The association of infantile diarrhoea with the occurrence of Candida species and their different morphological cell forms (pseudohyphae and/or blastospores) in faeces was studied in children of 0-15 months in a developing community (Lahore, Pakistan) where malnutrition is prevalent. Stool samples from 119 patients admitted to the Diarrhoea Treatment Unit, Department of Pediatrics, King Edward Medical College, and 46 healthy children were investigated for yeasts, bacteria, viruses and parasites. Salmonella and enteropathogenic Escherichia coli were seen in 13 (11%) each of the cases while Candida was the most frequent micro-organism, grown in cultures from 38 (32%) of the diarrhoea cases. C. tropicalis dominated (19%) over C. albicans (6%) and C. parapsilosis (3%). However, in a great number of cases (23, equals 19%), Candida did not grow in cultures but blastospores and/or pseudohyphae were seen on microscopical examination. Other Candida species and yeasts were relatively more common in the control group. Candida albicans, C. tropicalis and C. parapsilosis were the only identified agents in 23 of the cases (19%). The characteristic clinical findings in children with Candida as the only identified pathogen were malnutrition (69%), age less than 8 months (90%), and microscopically identified pseudohyphae in faecal smears (71%).     

Constant low rate of fungemia in norway, 1991 to 1996. The Norwegian Yeast Study Group

Since 1991 information on yeast isolates from blood cultures has been recorded prospectively from all microbiological laboratories (5 university and 16 county or local hospital laboratories) in Norway (population, 4.3 million). From 1991 to 1996 a total of 571 episodes of fungemia in 552 patients occurred (1991, 109 episodes; 1992, 81 episodes; 1993, 93 episodes; 1994, 89 episodes; 1995, 98 episodes; and 1996, 101 episodes). The fungemia rates per 10,000 patient days were 0.29 in 1991 and 0.27 in 1996. The average rates for the years 1991 to 1996 were 0.37 for the university laboratories and 0.20 for the other laboratories. These rates are low compared to the rate (0. 76) in five Dutch university hospitals in 1995 and the rate (2.0) in Iowa in 1991. The four most frequently isolated species were Candida albicans (66%), Candida glabrata (12.5%), Candida parapsilosis (7.6%), and Candida tropicalis (6.4%). The incidences of both C. albicans (range, 63 to 73%) and C. glabrata (range, 8.4 to 15.7%) varied somewhat throughout this period, but no significant increase or decrease was noted. MICs of amphotericin B, flucytosine, and fluconazole were determined for 89% of the isolates. All were susceptible to amphotericin B, and only 29 (5.6%) strains had decreased susceptibility to flucytosine. All C. albicans isolates were susceptible to fluconazole. The percentage of yeast isolates with decreased susceptibility to fluconazole (MICs, >/=16 microgram/ml) did increase, from 9.6% in 1991 and 1992 to 12.2% in 1994, 16.1% in 1995, and 18.6% in 1996. This was largely due to increases in the percentages of resistant C. glabrata and Candida krusei strains in the last 2 years. Compared to the incidence in other countries, it is remarkable that Norway has such a low and constant incidence of fungemia. A possible reason for this difference might be a restricted antibiotic use policy in Norway.     

International surveillance of bloodstream infections due to Candida species: frequency of occurrence and antifungal susceptibilities of isolates collected in 1997 in the United States, Canada, and South America for the SENTRY Program. The SENTRY Participant Group

An international program of surveillance of bloodstream infections (BSIs) in the United States, Canada, and South America between January and December 1997 detected 306 episodes of candidemia in 34 medical centers (22 in the United States, 6 in Canada, and 6 in South America). Eighty percent of the BSIs were nosocomial and 50% occurred in patients hospitalized in an intensive care unit. Overall, 53.3% of the BSIs were due to Candida albicans, 15.7% were due to C. parapsilosis, 15.0% were due to C. glabrata, 7.8% were due to C. tropicalis, 2.0% were due to C. krusei, 0.7% were due to C. guilliermondii, and 5.8% were due to Candida spp. However, the distribution of species varied markedly by country. In the United States, 43.8% of BSIs were due to non-C. albicans species. C. glabrata was the most common non-C. albicans species in the United States. The proportion of non-C. albicans BSIs was slightly higher in Canada (47.5%), where C. parapsilosis, not C. glabrata, was the most common non-C. albicans species. C. albicans accounted for 40.5% of all BSIs in South America, followed by C. parapsilosis (38.1%) and C. tropicalis (11.9%). Only one BSI due to C. glabrata was observed in South American hospitals. Among the different species of Candida, resistance to fluconazole (MIC, > or = 64 microg/ml) and itraconazole (MIC, > or = 1.0 microg/ml) was observed with C. glabrata and C. krusei and was observed more rarely among other species. Isolates of C. albicans, C. parapsilosis, C. tropicalis, and C. guilliermondii were all highly susceptible to both fluconazole (99.4 to 100% susceptibility) and itraconazole (95.8 to 100% susceptibility). In contrast, 8.7% of C. glabrata isolates (MIC at which 90% of isolates are inhibited [MIC90], 32 microg/ml) and 100% of C. krusei isolates were resistant to fluconazole, and 36.9% of C. glabrata isolates (MIC90, 2.0 microg/ml) and 66.6% of C. krusei isolates were resistant to itraconazole. Within each species there were no geographic differences in susceptibility to fluconazole or itraconazole.     

Comparison of the rapid yeast plus panel with the API20C yeast system for identification of clinically significant isolates of Candida species

The RapID Yeast Plus system (Innovative Diagnostic Systems, Norcross, Ga.) is a qualitative micromethod employing conventional tests and single-substrate chromogenic tests and having a 4-h incubation period. This system was compared with the API20C (bioMerieux Vitek, Hazelwood, Mo.) system, a 24- to 72-h carbohydrate assimilation method. One hundred thirty-three clinical yeast isolates, including 57 of Candida albicans, 26 of Candida tropicalis, 23 of Candida glabrata, and 27 of other yeasts, were tested by both methods. When discrepancies occurred, isolates were further tested by the Automated Yeast Biochemical Card (bioMerieux Vitek). Germ tube production and microscopic morphology were used as needed to definitively identify yeast isolates. The RapID Yeast Plus system correctly identified 125 yeast isolates, with an overall accuracy of 94% (125 of 133). Excellent correlation was found in the recognition of the three yeasts most commonly isolated from human sources. The test was 99% (105 of 106 isolates) accurate with C. albicans, C. tropicalis, and C. glabrata. The RapID Yeast Plus system compares favorably with the API20C system and provides a simple, accurate alternative to conventional assimilation methods for the rapid identification of the most commonly encountered isolates of Candida species.     

Tumor necrosis factor (TNF) induction from monocyte/macrophages by Candida species

Candida albicans was studied for its capacity to induce TNF production from mouse peritoneal macrophages (PM phi). TNF activities in the culture supernatants of Candida-stimulated PM phi and human peripheral blood monocytes were assessed by L 929 bioassay and ELISA respectively. C. albicans induced TNF production from PM phi and human peripheral blood monocytes in a dose-dependent manner. Although the capacity was lesser than live form, heat-killed C. albicans was also found to be capable of stimulating PM phi to induce TNF. The filtered supernatant of 24 h cultured live C. albicans had no effects on TNF production from PM phi. Saccharomyces cerevisiae-extracted mannan, a yeast cell wall antigen, induced TNF production from PM phi in a dose-dependent manner. Thus, the effect of C. albicans on TNF production from PM phi was seemed to be directly related to the presence of the yeast cell wall itself. Compatible with these data, when various candida species (C. albicans, C. tropicalis, C. pseudotropicalis. C. lusitaniae, C. krusei, C. parapsilosis, C. guilliermondii, C. stellatoidea, C. glabrata) and S. cerevisiae were compared to each other, at a concentration of 2 x 10(6) yeast cells/ml from each species, it was observed that TNF inducing capacities varied. Among the species used in this study, C. guilliermondii and C. glabrata, of which the yeast cell size were the smallest ones, were found to be less potent than that of others to induce TNF from PM phi.     

Phenotypic and genotypic characterization of oral yeasts from Finland and the United States

A total of 4-22 isolates of oral yeasts per subjects from 48 yeast-positive Finnish and American subjects (25 females and 23 males) were phenotyped and genotyped to determine the frequency of simultaneous oral carriage of multiple yeast taxa. An oral sample from either periodontal pockets, oral mucosa or saliva was obtained. All subjects yielded Candida albicans and 3 subjects an additional yeast species (Candida krusei, Candida glabrata or Saccharomyces cerevisiae). The API 20C Aux kit distinguished 9 different carbohydrate assimilation profiles among the C. albicans isolates. Thirty-eight of 46 C. albicans biotype I isolates were categorized in a single numerical profile. PCR analysis, using a random primer OPA-03 and a repetitive primer (GACA)4, detected 2 major genotypic groups among the C. albicans isolates; 44 subjects showing isolates with a "typical" PCR-profile and 4 subjects isolates with an "atypical" PCR-profile. The "atypical" PCR-profile was similar to that of Candida dubliniensis. All C. albicans isolates assimilated xylose, except 5, including the 4 with an "atypical" PCR-profile. No difference was found in distribution of oral yeast species, and of C. albicans phenotypes and genotypes between Finnish and American subjects. The present PCR method may offer a rapid and easy means of distinguishing oral Candida species.     

Fluorescence assay for the detection of adherent Candida yeasts to target cells in microtest plates

We describe an assay based on photometric analysis for the measurement of adherence of Candida species to epithelial target cells (Vero cell line). Adherent Candida cells were detected by staining the cells with the fluorescent dye Calcofluor white (CFW), which binds to chitin and glucan in the yeasts. The tests were performed on microtest plates, which were analysed automatically by fluorescence plate readers. The assay is based on the following steps: (i) coating of the microtest plates with target cells (e.g. Vero cells); (ii) infection with Candida: (iii) staining of Candida with CFW; (iv) rinsing to remove non-adherent Candida cells and unbound dye; (v) detection of adherent fluorescent Candida cells. The test was able to detect 4 x 10(4) cells ml-1. The standard deviation was +/- 8%. Day-to-day variation was +/- 10% at most. The adherence of strains of different Candida species was assayed by a standard procedure. The results confirmed the order of adherence, with C. albicans ranking first, followed by C. tropicalis, C. parapsilosis and C. glabrata.     

Pharmacokinetics of oral fluconazole in premature infants

Systemic infections with Candida albicans in neonates are a frequent and well recognized problem. The therapeutic gold standard in this situation is the combined intravenous antimycotic treatment with amphotericin B and flucytosine. Potential adverse effects of this regimen have encouraged the search for desirable alternatives. We report on the use of oral fluconazole in neonates with Candida albicans septicaemia. Three premature infants were treated with four courses of therapy. Pharmacokinetic studies were performed during each course. At oral doses of 4.5-6 mg/kg once a day, serum levels of fluconazole were within the therapeutic range during the entire dosage interval. Follow up showed microbiological and clinical cure in all patients with no side-effects. In one patient a dosage of 4 mg/kg per day lead to a microbiological relapse with sub-therapeutic serum levels. CONCLUSIONS: Oral fluconazole seems to be a safe and effective treatment for Candida albicans septicaemia even in premature infants.     

Comparative evaluation of macrodilution and alamar colorimetric microdilution broth methods for antifungal susceptibility testing of yeast isolates

A comparative evaluation of the macrodilution method and the Alamar colorimetric method for the susceptibility testing of amphotericin B, fluconazole, and flucytosine was conducted with 134 pathogenic yeasts. The clinical isolates included 28 Candida albicans, 17 Candida tropicalis, 15 Candida parapsilosis, 12 Candida krusei, 10 Candida lusitaniae, 9 Candida guilliermondii, 18 Torulopsis glabrata, and 25 Cryptococcus neoformans isolates. The macrodilution method was performed and interpreted according to the recommendations of the National Committee for Clinical Laboratory Standards (document M27-P), and the Alamar colorimetric method was performed according to the manufacturer's instructions. For the Alamar colorimetric method, MICs were determined at 24 and 48 h of incubation for Candida species and T. glabrata and at 48 and 72 h of incubation for C. neoformans. The overall agreement within +/- 1 dilution for Candida species and T. glabrata against the three antifungal agents was generally good, with the values for amphotericin B, fluconazole, and flucytosine being 85.3, 77.9, and 86.2%, respectively, at the 24-h readings and 69.3, 65.2, and 97.2%, respectively, at the 48-h readings. Most disagreement was noted with fluconazole against C. tropicalis and T. glabrata. Our studies indicate that determination of MICs at 24 h by the Alamar colorimetric method is a valid alternate method for testing amphotericin B, fluconazole, and flucytosine against Candida species but not for testing fluconazole against C. tropicalis and T. glabrata. For flucytosine, much better agreement can be demonstrated against Candida species and T. glabrata at the 48-h readings by the Alamar method. Excellent agreement within +/- dilution can also be observed for amphotericin B, fluconazole, and flucytosine (80, 96, and 96%, respectively) against c. neoformans when the MICs were determined at 72 h by the Alamar method.     

An alpha 5 beta 1-like integrin receptor mediates the binding of less pathogenic Candida species to fibronectin

The present study was undertaken to investigate whether less pathogenic Candida species (C. tropicalis, C. stellatoidea, C. krusei and C. glabrata) express a fibronectin receptor (FNr) antigenically related to alpha 5 beta 1 integrin, which mediates their binding to fibronectin (FN). By flow cytometric analysis, a monoclonal antibody (MAb) directed against human alpha 5 integrin subunit (clone SAM-1) and two different antisera to FNr positively stained C. tropicalis, C. stellatoidea and C. glabrata, with the greatest expression observed for C. tropicalis. No or only marginal immunoreactivity was found on C. krusei. C. tropicalis, C. stellatoidea, C. glabrata, but not C. krusei yeasts specifically adhered to FN; higher levels of adhesion were found for C. tropicalis and C. stellatoidea with respect to C. glabrata. Less pathogenic Candida spp. bound to the Arg-Gly-Asp (RGD) containing 120-kDa fragment of FN and adhesion to intact FN was markedly inhibited by Gly-Arg-Gly-Asp-Ser-Pro (GRGDSP), but not by Gly-Arg-Gly-Glu-Ser-Pro (GRGESP) peptides. In addition, anti-alpha 5 SAM-1 MAb and both anti-FNr antisera strongly blocked binding of less pathogenic Candida spp. to FN. Overall, these results indicate that less pathogenic Candida spp., including C. tropicalis, C. stellatoidea and C. glabrata, express a receptor antigenically related to alpha 5 beta 1 integrin which mediates their adhesion to FN.     

Antitumor effect of electrochemotherapy on colorectal carcinoma in an orthotopic mouse model

Although Candida albicans remains the fungal species most frequently isolated as an opportunistic oral pathogen, other yeast species are often identified in human immunodeficiency virus (HIV)-seropositive patients. Candida dubliniensis phenotypically resembles C. albicans in many respects, yet it can be identified and differentiated as a unique Candida species by its phenotypic and genetic profiles. The purpose of the present study was to prospectively test for the presence of C. dubliniensis among clinical isolates and to determine the clinical and demographic characteristics of patients harboring C. dubliniensis. Over a 90-day period, isolates from 724 patients that were presumptively identified as C. albicans were screened for C. dubliniensis by use of tests for germ tube and chlamydospore production, by detection of an inability to grow at 45 degrees C, by colony color on CHROMagar Candida medium, and by the results of a sugar assimilation test with the API 20C AUX yeast identification system. Among 699 isolates retrieved from those specimens evaluated, 5 from 25 HIV-seropositive patients and 1 isolate from a patient whose HIV status was unknown were shown to be consistent by phenotyping and by electrophoretic karyotyping with the European reference strain of C. dubliniensis. One of the C. dubliniensis isolates had dose-dependent susceptibility to fluconazole (MIC, 16 microg/ml). These results confirm the presence of this interesting species in the United States and support the need for further investigations into the prevalence and pathogenesis of C. dubliniensis.     

2,4-(hydroxyphenyl)-ethanol, an antioxidative agent produced by Candida spp., impairs neutrophilic yeast killing in vitro

Culture supernatants of Candida albicans were examined for factors with inhibitory activity against the chemiluminescence of human neutrophils. By high resolution gel chromatography, a low-molecular-mass chemiluminescence inhibitor was isolated. The compound was identified as 2,4-(hydroxyphenyl)-ethanol. Half-maximum inhibition (IC50) of the chemiluminescence response of neutrophils phagocytizing opsonized zymosan or C. albicans occurred at 38.1 +/- 2.3 microM and 19.9 +/- 8.3 microM, respectively. As shown by flow cytometry, the compound protected C. albicans against phagocytic killing (IC50 = 73.8 +/- 16.9 microM). Substantially higher concentrations of the inhibitor were produced by C. albicans and C. tropicalis than by C. parapsilosis and C. glabrata, suggesting a potential role in pathogenicity ranking.     

Chronic neutrophilic meningitis caused by Candida albicans

Meningitis caused by Candida albicans is a very infrequent entity. We present 3 intravenous drug users with chronic neutrophilic meningitis caused by Candida albicans. The clinical, microbiological and radiological features of the 3 patients are reviewed. The interval between the onset of the disease and the diagnosis was long (from 4 to 12 months). Candida albicans was cultured from cerebrospinal fluid (CSF) in the 3 patients. All of them developed hydrocephalus, meanwhile arachnoiditis was disclosed in two. The therapy with amphotericyn, 5-flucytosine and fluconazole produced clinical improvement and the sterilisation of the CSF in all the 3 cases. Clinicians should be aware of this entity because of diagnosis may be delayed in several months.     

Evaluation of the echinocandin antifungal MK-0991 (L-743,872): efficacies in mouse models of disseminated aspergillosis, candidiasis, and cryptococcosis

The in vivo activity of the Merck antifungal echinocandin drug candidate MK-0991 (L-743,872) was evaluated in mouse models of disseminated candidiasis, aspergillosis, and cryptococcosis. The echinocandins are potent inhibitors of 1,3-beta-D-glucan synthase. Two models of disseminated candidiasis were used. In a Candida albicans mouse survival model with both DBA/2N and CD-1 mice, estimates of the 50% effective doses (ED50s) of MK-0991 were 0.04 and 0.10 mg/kg of body weight/dose at 21 days after challenge, respectively. In a C. albicans target organ assay (TOA) with DBA/2N mice, MK-0991 at levels of > or =0.09 mg/kg/dose significantly reduced the numbers of C. albicans CFU/g of kidneys compared to the numbers in the kidneys of control mice from 1 to 28 days after challenge. Even when given as a single intraperitoneal dose either 30 min or 24 h after challenge, MK-0991 was effective and significantly reduced the numbers of C. albicans CFU/g of kidney compared to those in the controls. MK-0991 was >300-fold less active when it was administered orally than when it was administered parenterally. MK-0991 was efficacious in mouse TOAs against other C. albicans strains and Candida species including Candida tropicalis, Candida (Torulopsis) glabrata, Candida lusitaniae, Candida parapsilosis, and Candida krusei. MK-0991 was ineffective against disseminated Cryptococcus neoformans infections. In the model of disseminated aspergillosis in mice, MK-0991 at doses of > or =0.02 mg/kg/dose significantly prolonged the survival of DBA/2N mice, with estimates of the ED50 and ED90 of MK-0991 being 0.03 and 0.12 mg/kg/dose, respectively, at 28 days after challenge. MK-0991 is a potent, parenterally administered therapeutic agent against disseminated candidiasis and aspergillosis that warrants further investigation in human clinical trials.     

(-)Deprenyl (selegiline), a catecholaminergic activity enhancer (CAE) substance acting in the brain

Fast and reliable identification of different species of the genus Candida is important to define adequate therapeutic decisions, because the different species have highly variable susceptibilities to antifungal drugs; azoles and amphothericin B. Accurate statistical records on case history and epidemiological studies also depend on effective identification. To address this problem we established a RAPD method that enabled direct identification of five very common species of Candida. Initially, reference band patterns were established for C. albicans, C. tropicalis, C. parapsilosis, C. glabrata and C. krusei. One of the primers, M2, showed remarkably conserved intra-specific patterns of approximately 10 bands each, ranging in size from 2.0 to 0.1 kb. These patterns were significantly different and species-specific. Few bands were conserved between different species of Candida, which was assumed to be consistent with their phylogenetic relatedness. In addition, band patterns were constant and reproducible and DNA isolated from single colonies yielded sufficient DNA for identification. The reference band patterns were then used, in blind experiments, to identify species of Candida in 50 randomly chosen samples, including clinical isolates and ATCC strains. RAPD results were 100% consistent with results obtained by conventional diagnostic methods and were achieved in one day instead of several days taken by conventional methods. Because ideal identification methods should be consistent with phylogeny and taxonomy we tested whether RAPD could be used to calculate genetic distances. Comparison of RAPD phylogenetic trees with 18S rRNA trees showed significant differences in tree topologies which indicated that RAPD data could not accurately measure the relative distances between different species. Also, computer simulations of RAPD random patterns were used to test whether the observed degree of RAPD band pattern similarities could occur at random. These simulations suggested that the level of inter-specific band pattern similarities observed in our data could be obtained at random, while intraspecific pattern similarities could not. RAPD would be helpful to discriminate between isolates but not to quantitate the differences. We suggest that the inaccurate estimate of genetic distances from RAPD is a general limitation of the technique and not a specific problem of our identification method. Because of the repetitive character of the target sequences, genetic distances calculated from RAPD could be affected by paralogy, namely, recombination and duplication events not parallel with speciation events.