Anabolic steroids affect human periodontal health and microbiota.

OBJECTIVES: This study aims to evaluate periodontal microbiological differences between systemically healthy nonsmoker males taking anabolic androgenic steroids (AASs) and non-AAS users and to find associations between disease severity and AAS use. METHODS: Ninety-two men practicing bodybuilding were included in the study. They were divided into AAS users and a matched control nonuser group and subgrouped based on their most severe periodontal condition. Pooled subgingival samples from each individual were cultured to evaluate specific periodontopathogen infection. RESULTS: AAS users had significantly higher prevalence of severe periodontitis. AAS users had greater gingival inflammation and clinical attachment loss of ≥ 3 mm than nonusers (odds ratio (OR) = 2.4; p = 0.09; 95 % confidence interval (CI) 0.8-6.4). AAS users were 4.9 times more likely to be infected with Prevotella intermedia than AAS nonusers (OR = 4.9; p = 0.003; 95 % CI 1.6-14.7). The OR of presenting subgingival Aggregatibacter actinomycetemcomitans was 8.2 times higher in AAS users (OR = 8.2; p = 0.03; 95 % CI 0.9-70.8). AAS users were 5.6 times more likely to present subgingival Candida spp. than nonusers (OR = 5.6; p = 0.02; 95 % CI 1.1-27.1). AAS users were 14.8 times more likely to present subgingival Candida parapsilosis than nonusers (OR = 14.8; p < 0.0001; 95 % CI 3.1-69.2). The likelihood of AAS users presenting subgingival Candida tropicalis was 4.3 times higher than nonusers (OR = 4.3; p = 0.03; 95 % CI 1.1-16.9). A. actinomycetemcomitans was mostly isolated in individuals with severe periodontitis and was associated with subgingival Porphyromonas gingivalis, P. intermedia, and Candida spp. CONCLUSIONS: AAS use may increase the risk for severe periodontitis and may cause a subgingival selection of certain Candida species. Specific periodontopathogens, such as Candida dubliniensis and Candida albicans, seem to be negatively affected by AAS use. The higher risk for disease progression in AAS users may be explained by the significantly higher proportions of A. actinomycetemcomitans, P. gingivalis, P. intermedia, and Candida species as compared to controls. CLINICAL SIGNIFICANCE: Data on the influence of AAS on subgingival periodontopathogens and disease progression are scarce. Higher proportions of specific periodontopathogens are plausible in AAS users. AAS users had a higher prevalence of severe periodontitis, gingival inflammation, and clinical attachment loss. Men taking AAS are at greater risk of periodontitis and specific periodontopathogen infection.

Fungicidal monoclonal antibody C7 interferes with iron acquisition in Candida albicans.

We have developed a monoclonal antibody (MAb), C7, that reacts with the Als3p and enolase present in the Candida albicans cell wall and exerts three anti-Candida activities: candidacidal activity and inhibition of both adhesion and filamentation. To investigate the mode of action of MAb C7 on fungal viability, we examined changes in the genome-wide gene expression profile of C. albicans grown in the presence of a subinhibitory concentration of MAb C7 (12.5 µg/ml) by using microarrays. A total of 49 genes were found to be differentially expressed upon treatment with MAb C7. Of these, 28 were found to be upregulated and 21 were found to be downregulated. The categories of upregulated genes with the largest number of variations were those involved in iron uptake or related to iron homeostasis (42.86%), while the energy-related group accounted for 38.10% of the downregulated genes (8/21). Results were validated by real-time PCR. Since these effects resembled those found under iron-limited conditions, the activity of MAb C7 on C. albicans mutants with deletions in key genes implicated in the three iron acquisition systems described in this yeast was also assessed. Only mutants lacking the TPK1 gene and, to a lesser extent, the TPK2 gene were less sensitive to the candidacidal effect of MAb C7. FeCl(3) or hemin at concentrations of ≥ 7.8 µM reversed the candidacidal effect of MAb C7 on C. albicans in a concentration-dependent manner. The results presented in this study provide evidence that the candidacidal effect of MAb C7 is related to the blockage of the reductive iron uptake pathway of C. albicans.

Bone microbial contamination influences autogenous grafting in sinus augmentation.

BACKGROUND: The oral occurrence of putative microbial pathogens in humans has been documented in health and disease. The presence of periodontopathogens in patients with a history of periodontal disease may have a negative impact on bone regeneration. This investigation was conducted to confirm the presence of periodontal pathogens in bone particles harvested intraorally for maxillary sinus augmentation and to assess the clinical and radiographic outcomes 6 to 12 months after bone augmentation. METHODS: Culture and polymerase chain reaction (PCR)-based identification were performed by paper-point sampling of intraorally harvested bone particles in a group of 12 maintenance patients undergoing maxillary sinus augmentation. Radiographs were taken to assess and compare bone healing and volume gain at baseline and at 6 to 12 months after augmentation. RESULTS: The presence of periodontal pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans [previously Actinobacillus actinomycetemcomitans], Prevotella intermedia, Tannerella forsythia [previously T. forsythensis], Fusobacterium nucleatum, Parvimonas micra [previously Peptostreptococcus micros or Micromonas micros], Campylobacter rectus, enteric Gram-negative rods, and Dialister pneumosintes) was identified in 10 of 12 patients (83%) by culture, PCR, or both and was associated with greater bone volume loss at 6 months postaugmentation. The PCR-positive triad, P. gingivalis, A. actinomycetemcomitans, and P. intermedia, was associated with pronounced volume loss of the grafted sinus at 6 months. CONCLUSIONS: To the best of our knowledge, this is the first study to confirm osseous microbial contamination with major periodontopathogens in individuals undergoing maxillary sinus augmentation with a history of periodontitis. The effect on the grafting outcome translated into bone volume loss in the grafted sinus 6 months postaugmentation. Specific microbial contamination may have an impact on osteogenesis in osseous regeneration.

Monoclonal antibody-mediated inhibition of adhesion of Candida albicans and Candida dubliniensis to human epithelial cells.

The aim of this study was to assess the role of whole saliva, four saliva-derived preparations, and six monoclonal antibodies (mAbs), directed against components of the cell wall of Candida albicans, on the adhesion of C. albicans and Candida dubliniensis to human epithelial cells (HEC). C. albicans serotype A NCPF 3153 and C. albicans serotype B ATCC 90028 showed higher adhesion to HEC than C. dubliniensis NCPF 3949. Pooled whole saliva was more efficient than salivary secretory immunoglobulin A, partially purified by chromatography, at inhibiting the adhesion of C. albicans serotype A NCPF 3153 to HEC. Monoclonal antibodies C7, 14-8, and 26G7 were the most potent inhibitors of adhesion. Our results show that mAbs can mimic the inhibition of adhesion of C. albicans to HEC that is mediated by human saliva.

Diagnosis of invasive candidiasis by enzyme-linked immunosorbent assay using the N-terminal fragment of Candida albicans hyphal wall protein 1.

BACKGROUND: The diagnosis of invasive candidiasis is difficult because there are no specific clinical manifestations of the disease and colonization and infection are difficult to distinguish. In the last decade, much effort has been made to develop reliable tests for rapid diagnosis of invasive candidiasis, but none of them have found widespread clinical use. RESULTS: Antibodies against a recombinant N-terminal fragment of the Candida albicans germ tube-specific antigen hyphal wall protein 1 (Hwp1) generated in Escherichia coli were detected by both immunoblotting and ELISA tests in a group of 36 hematological or Intensive Care Unit patients with invasive candidiasis and in a group of 45 control patients at high risk for the mycosis who did not have clinical or microbiological data to document invasive candidiasis. Results were compared with an immunofluorescence test to detect antibodies to C. albicans germ tubes (CAGT). The sensitivity, specificity, positive and negative predictive values of a diagnostic test based on the detection of antibodies against the N-terminal fragment of Hwp1 by immunoblotting were 27.8 %, 95.6 %, 83.3 % and 62.3 %, respectively. Detection of antibodies to the N-terminal fragment of Hwp1 by ELISA increased the sensitivity (88.9 %) and the negative predictive value (90.2 %) but slightly decreased the specificity (82.6 %) and positive predictive values (80 %). The kinetics of antibody response to the N-terminal fragment of Hwp1 by ELISA was very similar to that observed by detecting antibodies to CAGT. CONCLUSION: An ELISA test to detect antibodies against a recombinant N-terminal fragment of the C. albicans germ tube cell wall antigen Hwp1 allows the diagnosis of invasive candidiasis with similar results to those obtained by detecting antibodies to CAGT but without the need of treating the sera to adsorb the antibodies against the cell wall surface of the blastospore.

Cross-reactivity between Candida albicans and oral squamous cell carcinoma revealed by monoclonal antibody C7.

BACKGROUND: Monoclonal antibodies developed against Candida albicans cell wall mannoproteins cross-react with human ovarian cancer. These antibodies reacted with the nuclear pore complex protein Nup88, which is overexpressed in a number of human tumors. The aim of this study was to investigate if Nup88 revealed by monoclonal antibody C7 is overexpressed in early oral squamous cell carcinoma (EOSCC) and if this expression has a prognostic value. PATIENTS AND METHODS: A monoclonal antibody against a C. albicans cell wall manoprotein was used to investigate the expression of Nup88 in 34 EOSCC (T1/T2 N0M0). RESULTS: Mab C7 was mostly located in the cytoplasm and extracts from EOSCC showed specific bands of 47-40 and 70 kDa that were not observed in normal oral mucosa. The highest levels of Mab C7 reactivity were observed in 13 (38.2%) tumors. The Kaplan-Meier test showed the median survival time to be shorter in those EOSCC cases with the highest Mab C7 reactivity. CONCLUSION: The monoclonal antibody C7 raised against a C. albicans cell wall mannoprotein cross-reacts with an antigen from oral squamous cell carcinoma whose expression is associated with poor prognosis. The overexpression of this antigen is associated with a poor prognosis in early squamous cell carcinoma.

Evaluation of Bichro-Dubli Fumouze to distinguish Candida dubliniensis from Candida albicans.

We have evaluated the ability of the Bichro-Dubli Fumouze (Fumouze Diagnostics, Levallois-Perret, France) latex agglutination test to identify colonies of Candida dubliniensis grown on different media. The test was positive for 103 of 106 isolates of C. dubliniensis and negative for Candida albicans and other Candida species studied. The sensitivity and specificity of the test were 97.1% and 100%, respectively. The test is very rapid, simple, and reliable giving the same results independently of whether the colonies are grown previously on Sabouraud dextrose agar, CHROMagar Candida medium, Candida ID2 medium, or CHROMagar-Pal's medium.

Identification and characterization of nine atypical Candida dubliniensis clinical isolates.

Candida dubliniensis is a pathogenic yeast of the genus Candida closely related to Candida albicans. The phenotypic similarity of these two species often leads to misidentification of C. dubliniensis isolates in clinical samples. DNA-based methods continue to be the most effective means of discriminating accurately between the two species. Here, we report on the identification of nine unusual Candida isolates that showed ambiguous identification patterns on the basis of their phenotypic and immunological traits. The isolates were categorized into two groups. Group I isolates were unable to produce germ tubes and chlamydospores, and to agglutinate commercial latex particles coated with a mAb highly specific for C. dubliniensis. Group II isolates grew as pink and white colonies on CHROMagar Candida and ChromID Candida, respectively. Carbohydrate assimilation profiles obtained with API/ID32C together with PCR amplification with specific primers and DNA sequencing allowed reliable identification of the nine unusual clinical isolates as C. dubliniensis.

Periodontopathogen and Epstein-Barr virus contamination affects transplanted bone volume in sinus augmentation.

BACKGROUND: Bone microbial contamination can impair osteogenesis. Human herpesviruses-associated vasculitis can cause vascular damage within the osseous graft and host. This study is conducted to substantiate specific contamination and assess the impact 6 months after sinus augmentation. METHODS: Culture- and polymerase chain reaction (PCR)-based identification were done on harvested bone particles and unstimulated whole saliva in a group of 30 patients undergoing maxillary sinus augmentation. Patients were divided into two groups: those with and those without a history of periodontitis. Radiographic evaluation was done to assess and compare bone healing and volume gain at baseline and 6 months post-transplantation. RESULTS: Seventeen patients had a history of periodontitis, and 13 did not. Ten showed culture- and PCR-negative results and belonged to the periodontally healthy group. The 17 patients with periodontitis showed culture- or PCR-positive results for the targeted periodontal pathogens. Patients with periodontitis were 2.3 times more likely to have positive salivary Epstein-Barr virus type 1 (EBV-1) than those with no history of periodontitis. The likelihood of having moderate to pronounced bone volume loss 6 months postaugmentation was 7.5 times greater in those patients presenting contamination with ≥3 specific pathogens (Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia, or Prevotella intermedia) versus those with only one (P <0.05). The odds ratio (OR) of pronounced volume loss was 16.3 times higher in those contaminated with a combination of salivary EBV-1 and ≥3 of the previously mentioned species versus only EBV-1 (P <0.05). Individuals showing positive salivary EBV-1 had bone bacterial contamination associated 57% of the time. The OR of having bone microbial contamination in patients with a history of periodontitis was 37.5 times higher than in individuals without periodontitis. CONCLUSIONS: This study confirms contamination of bone, harvested intraorally, with key periodontopathogens in individuals undergoing sinus augmentation. Specific microbial contamination can impair osteogenesis. Saliva may act as a vehicle to transport EBV and other pathogens into the sinus. Increased bone volume loss seems to be associated with the occurrence of specific periodontal anaerobic species, salivary EBV-1, or the combination of both.

Bone microbial decontamination agents in osseous grafting: an in vitro study with fresh human explants.

BACKGROUND: Establishing a safe prophylactic antimicrobial protocol in bone grafting may enhance osseous volume outcomes. The purpose of this in vitro study is to assess human osteoblast response and safety after explant antimicrobial exposure. METHODS: Fresh human bone explants were exposed to three antimicrobials: povidone-iodine (PovI; 0.05%, 1%, and 5%), chlorhexidine (CHX; 0.2% and 1%), and sodium hypochlorite (NaOCl; 2.5%, 4.5%, and 5.25%) at different times (15, 30, 45, and 60 seconds) and concentrations to assess cellular toxicity. Explants were washed three times with saline after exposure. Controls, explants cultured in the absence of antimicrobials, were performed for all experimental situations tested. Trials were conducted in triplicate. Particle size influence on osteoblast growth was determined between bone fragments with a diameter <2 and ≥2 to 5 mm. Test and control groups were monitored by light microscopy to evaluate cellular growth. Osteoblast differentiation and morphology was assessed by alkaline phosphatase activity and scanning electron microscopy (SEM). RESULTS: Osteoblast growth was similar for particles <2 and ≥2 to 5 mm. Alkaline phosphatase control reference values were not significantly different from test groups (0.35 mU/mL ± 0.004 versus 0.34 mU/mL ± 0.009; P >0.05). Light microscopy showed on average 97% osteoblastic growth for bone particles exposed to PovI 5% and CHX 0.2% for all times and CHX 1% up to 30 seconds. The odds ratio of positive osteoblastic growth after a 30-second 2.5% NaOCl exposure was 2.4 times higher than after 5.25%. On average, one of two replicas yielded positive growth with 2.5% NaOCl and one of three with 5.25%. After 60-second explant exposure, positive osteoblastic growth was 7.7 times more likely to occur with 5% PovI or 0.2% CHX than with 5.25% NaOCl (P <0.05). SEM analysis confirmed light microscopy similar cellular adhesion and osteoblast phenotypic features between test and control groups. CONCLUSIONS: Best osteoblastic growth occurred after bone PovI exposure and CHX 0.2%. Cellular toxicity seems to be influenced by the type of antimicrobial, concentration, and exposure time. SEM analysis confirmed absence of osteoblast phenotypic alterations after exposure. Decontamination agents can safely be used in bone transplantation using up to 5% PovI and 0.2% CHX for 1 minute and CHX 1% for 30 seconds.

Potential of anti-Candida antibodies in immunoprophylaxis.

The need for new options for the treatment of invasive candidiasis has fuelled the use of antibodies in combination with conventional antifungal therapy. After a long period of time in which antibodies were considered irrelevant in the resistance against invasive candidiasis, it was demonstrated that a number of antibodies or their engineered derivatives directed against Candida albicans cell-wall polysaccharides and glycopeptides, as well as against some protein epitopes, confer protection against invasive candidiasis. This has confirmed this approach as a new strategy for the prophylaxis of invasive candidiasis. Of particular interest is Mycograb, a human recombinant monoclonal antibody that inhibits heat shock protein 90, and has been administrated in combination with lipid-associated amphotericin B to patients with invasive candidiasis, and the fungicidal anti-beta-glucan antibodies induced by the glycoconjugate vaccine composed of a beta-glucan polysaccharide conjugated with the diphtheria toxoid CRM 197. However, despite the promising data obtained in vitro and in animal models, at present there is very little clinical experience on the use of antibodies in Candida immunoprophylaxis.

The impact of oral contraceptives on women's periodontal health and the subgingival occurrence of aggressive periodontopathogens and Candida species.

BACKGROUND: The purpose of this study is to evaluate the influence of oral contraceptive (OC) use on the subgingival occurrence of specific periodontopathogens and the host's periodontal status. METHODS: Ninety-two females aged 19 to 40 years were included in the study. They were divided into two groups, OC users and non-users, and subgrouped according to the most severe periodontal condition and duration of OC usage. A pooled subgingival sample from each subject was cultured to investigate the presence of Candida species, Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), and Prevotella intermedia. RESULTS: OC users, particularly smokers, show a statistically significant increase in the prevalence of severe periodontitis. OC users had deeper probing depths (>or=5 mm) than non-users. Moreover, OC users had higher gingival index scores and clinical attachment loss, >or=2 and >or=5 mm, respectively, than non-users (P <0.01). Patients taking OCs had significantly higher numbers of cultures positive for Candida. Seven Candida species were isolated. Subgingival Candida was associated with P. gingivalis and P. intermedia in 82.9% and 85.4%, respectively, in patients taking OCs. A. actinomycetemcomitans was isolated in patients with moderate and severe periodontitis and was associated with subgingival P. gingivalis, P. intermedia, and Candida. CONCLUSIONS: OC use may increase the risk of severe periodontitis and seems to cause a selection of certain Candida species in periodontal pockets. OC users showed a higher prevalence of P. gingivalis, P. intermedia, and A. actinomycetemcomitans compared to non-users. C. albicans, C. parapsilosis, C. krusei, C. tropicalis, and C. glabrata were the species with the ability to survive in the conditions created by the sex hormones after 3 years.

Evaluation of CHROM-Pal medium for the isolation and direct identification of Candida dubliniensis in primary cultures from the oral cavity.

Candida albicans is the species most frequently isolated from oral specimens, but the recovery of other Candida species such as Candida dubliniensis is increasing. Differentiation of C. dubliniensis from C. albicans requires special tests and both species are misidentified in some studies. CHROM-Pal (CH-P) is a novel chromogenic medium used in our laboratory for differentiation between C. albicans and C. dubliniensis on the basis of colony colour and morphology, and chlamydospore production. The performance of CH-P and CHROMagar Candida (CAC) was compared for primary isolation and presumptive identification of yeasts from oral specimens from human immunodeficiency virus (HIV)-infected and uninfected individuals. The identification of Candida species on both media was compared with two reference identification methods (API ID 32 C and multiplex PCR). A total of 137/205 oral swabs (66.8 %) plated onto CH-P and CAC media were positive by culture and resulted in the growth of 171 isolates of Candida species on CH-P, whilst only 159 isolates grew on CAC. C. albicans was the most frequently isolated species in both groups of patients, followed by Candida parapsilosis in the HIV-negative group, and by C. dubliniensis in the HIV-infected group. The other Candida species isolated were Candida guilliermondii, Candida glabrata, Candida krusei, Candida tropicalis, Candida famata, Candida rugosa, Candida kefyr, Candida pelliculosa and Candida pulcherrima. The sensitivity and specificity for identifying C. albicans, C. krusei, C. tropicalis and C. dubliniensis on CH-P were over 98.5 %, always equal to or higher than those obtained when CAC was used. CH-P is a simple reliable medium for primary isolation and presumptive identification of yeast isolates from oral samples. The ability of CH-P to discriminate between C. dubliniensis and C. albicans was significantly higher (P <0.05) than that of CAC.

Fungicidal monoclonal antibody C7 binds to Candida albicans Als3.

Monoclonal antibody (MAb) C7 reacted with a >200-kDa component from the Candida albicans cell wall identified by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry as Als3. It also bound the recombinant N terminus of Als3. Binding of MAb C7 to Als3 may explain the biological activities exerted by the MAb on C. albicans.

[Rapid identification of Candida dubliniensis using the Bichro-Dubli test]. / Identificación rápida de Candida dubliniensis mediante la prueba Bichro-Dubliì

OBJECTIVES: Because of its considerable epidemiological relevance, accurate identification of Candida dubliniensis should be routinely performed in clinical microbiology laboratories. In an attempt to facilitate this task, the usefulness of the Bichro-Dubli test (Fumouze Diagnostics, Levallois-Perret, France) was assessed. METHODS: Seventy-five collection strains (55 C. dubliniensis and 20 C. albicans) and 135 clinical yeast isolates that grew as green colonies in CHROMagar Candida were studied. RESULTS: Bichro-Dubli was positive in 54 of 55 C. dubliniensis strains (sensitivity 98.2%) and negative in the 20 C. albicans strains (specificity 100%). The test identified 4 C. dubliniensis isolates among the 135 isolates cultured from clinical specimens. CONCLUSIONS: The Bichro-Dubli test is easy to perform and allows rapid identification of C. dubliniensis.

Evaluation of a novel enzyme-linked immunosorbent assay to detect immunoglobulin G antibody to enolase for serodiagnosis of invasive candidiasis.

The performance of a new test to detect antibodies to Candida albicans recombinant enolase was investigated in 47 immunocompromised and 51 immunocompetent patients. The sensitivity, specificity, and positive and negative predictive values of the test for the diagnosis of invasive candidiasis were 81.0, 83.9, 79.1, and 85.5%, respectively.

A fungicidal monoclonal antibody protects against murine invasive candidiasis.

Mice infected by Candida albicans and treated with monoclonal antibody C7 survived longer than saline-treated animals. A prozone-like effect was observed. The in vitro candidacidal activity of macrophages was strongly enhanced when C. albicans was opsonized by C7 and complete murine serum was present.

Evaluation of the new chromogenic medium Candida ID 2 for isolation and identification of Candida albicans and other medically important Candida species.

The usefulness of Candida ID 2 (CAID2) reformulated medium (bioMérieux, France) has been compared with that of the former Candida ID (CAID; bioMérieux), Albicans ID 2 (ALB2; bioMérieux), and CHROMagar Candida (CAC; Chromagar, France) chromogenic media for the isolation and presumptive identification of clinically relevant yeasts. Three hundred forty-five stock strains from culture collections, and 103 fresh isolates from different clinical specimens were evaluated. CAID2 permitted differentiation based on colony color between Candida albicans (cobalt blue; sensitivity, 91.7%; specificity, 97.2%) and Candida dubliniensis (turquoise blue; sensitivity, 97.9%; specificity, 96.6%). Candida tropicalis gave distinguishable pink-bluish colonies in 97.4% of the strains in CAID2 (sensitivity, 97.4%; specificity, 100%); the same proportion was reached in CAC, where colonies were blue-gray (sensitivity, 97.4%; specificity, 98.7%). CAC and CAID2 showed 100% sensitivity values for the identification of Candida krusei. However, with CAID2, experience is required to differentiate the downy aspect of the white colonies of C. krusei from other white-colony-forming species. The new CAID2 medium is a good candidate to replace CAID and ALB2, and it compares well to CAC for culture and presumptive identification of clinically relevant Candida species. CAID2 showed better results than CAC in some aspects, such as quicker growth and color development of colonies from clinical specimens, detection of mixed cultures, and presumptive differentiation between C. albicans and C. dubliniensis.

Supplementation of CHROMagar Candida medium with Pal's medium for rapid identification of Candida dubliniensis.

CHROMagar Candida medium is used for the isolation and identification of Candida species, but it does not differentiate Candida albicans from Candida dubliniensis. This differentiation can be achieved by using Pal's agar, which cannot be used in primary isolation. We have combined both media to obtain a new medium that can be used for the isolation and identification of C. dubliniensis in primary cultures.

Casein agar: a useful medium for differentiating Candida dubliniensis from Candida albicans.

Production of chlamydospores on casein agar at 24 degrees C for 48 h provides a simple means for differentiating Candida dubliniensis from Candida albicans based on chlamydospore production. Of 109 C. dubliniensis isolates tested on this medium, 106 (97.2%) produced abundant chlamydospores and three produced few chlamydospores. In contrast, of the 120 C. albicans isolates tested, 111 (92.5%) failed to produce any chlamydospores, whereas the remaining nine isolates produced few chlamydospores. These findings indicate that abundant chlamydospore production on casein agar is a useful test for discriminating between C. dubliniensis and C. albicans.