Antifungal Susceptibility Of Candida Albicans Research Articles

Frequency and Antifungal Susceptibility of Candida Albicans and Non-Albicans Candida Isolates from Diabetic Foot Ulcer at Tertiary Care Hospitals of Peshawar

Frequency and Antifungal Susceptibility of Candida Albicans and Non-Albicans Candida Isolates from Diabetic Foot Ulcer at Tertiary Care Hospitals of Peshawar

In Vitro Antifungal Susceptibility of Candida Albicans Isolated from Yemeni Patients with Denture Stomatitis

Background and aims: Candida-associated denture stomatitis (CADS) is a common fungal infection in people who wear dentures. The main objectives of this study were to identify the causative agents of CADS and in vitro antifungal susceptibility testing (AFST) for Candida albicans in Yemeni patients with denture stomatitis. Methods: A total of 88 Candida spp. obtained from patients with denture stomatitis. Candida spp were identified using standard microbiological methods. The in-vitro antifungal susceptibility of Candida albicans. to fluconazole (FCZ), itraconazole (ICZ), voriconazole (VCZ), and amphotericin B (AMB) was evaluated using the E test strips. Interpretive sensitivity criteria for antifungal breakpoints were adapted from the Clinical and Laboratory Standards Institute (CLSI). Results: Overall, C. albicans was the most commonly isolated species (𝑛 = 60; 68.2%), followed by C. glabrata (𝑛 = 9; 10.2%), C. tropicalis (𝑛 = 7; 8%), and C. parapsilosis (𝑛 = 3; 3.4%). Voriconazole had the lowest geometric mean minimum inhibitory concentration which was 0.0418 𝜇g/ml for MIC50, and 0.957 𝜇g/ml for MIC90; followed by amphotericin B (AMB) in which MIC50 was 0.518 𝜇g/ml and for MIC90 was 1.06 𝜇g/ml. Conclusion: Our study showed that Candida albicans was the most prevalent Candida species in Yemeni patients with CADS and was susceptible to both azoles and amphotericin B. In addition, voriconazole could be a suitable alternative to antifungal agents currently used in the treatment of CADS, as well as in the treatment of recurrent Candidasis.

Multilocus Sequence Typing and Antifungal Susceptibility of Candida albicans Isolates From Milk and Genital Tract of Dromedary Camel.

Multilocus sequence typing (MLST) was used to study the genetic diversity and population structure of 48 Candida albicans (C. albicans) isolates from the udder or genital tract of apparently healthy or diseased camels. This study aimed also to determine the frequency of C. albicans isolates in the genital tract and udder of healthy or diseased female dromedary camels. A total of 240 mature dromedary camels (230 females and 10 males) were categorized based on the clinical examination of gentile tract and udder into five groups [fertile females (n = 70), infertile females (n = 115), healthy udder (n = 15), mastitis (n = 30), and fertile males (n = 10)]. Swabs were collected from male and female genital tracts of dromedary camels and milk samples were collected from healthy and diseased udders. C. albicans was isolated from 20% of the samples. The frequency of isolation was significantly higher (p < 0.00001) in disease camels (75%) compared with apparently healthy camels (25%). Most of C. albicans was isolated from infertile female genitalia (62.50%) which was significantly higher than that isolated from fertile female genitalia (16.67%). Multilocus sequence (MLS) analysis identified seven different diploid sequence types (DSTs) including DST2, DST50, DST62, DST69, DST124, DST142, and DST144. The most frequently identified DTS was DST69 (13/48) which significantly higher (p ≤ 0.05) than DST2, DST62, and DST124. The frequency of identification of DST50, DST142, and DST 144 was significantly higher (p ≤ 0.05) than DST62. DST62 and DST124 were isolated only from diseased camels. DST62 was isolated only from mastitic milk. DST124 was isolated only from infertile female genitalia. The percentage of DST50 and DST 142 was significantly higher in diseased camels (infertile females) than in the apparently healthy ones (fertile females). DST2 and DST50 were isolated only from female genitalia of apparent health and diseased camels. The C. albicans isolated from diseased camels had significantly higher biofilm formation, hydrophobicity, phospholipase, proteinase, and hemolysin activities compared with the isolates from apparent healthy camels. All isolates were sensitive to amphotericin B, itraconazole, micafungin, posaconazole and voriconazole. In conclusion, the present study represents the first molecular typing of C. albicans in samples isolated from milk and the genital tract of the dromedary camel. MLST is a useful tool for studying the epidemiology and evolution of C. albicans. Early identification of Candida species and attention to Candida virulence factors and their antifungal susceptibility patterns is very important for establishing strategies to control and/or prevent candidiasis by novel therapeutic management. Amphotericin B, itraconazole, micafungin, posaconazole, or voriconazole can be efficient in treatment of candidiasis.

Garlic-induced Proteomic Change, Anti-biofilm and Antifungal Susceptibility of Candida albicans

Garlic-induced Proteomic Change, Anti-biofilm and Antifungal Susceptibility of Candida albicans

Prevalence, species distribution and antifungal susceptibility of Candida albicans causing vaginal discharge among symptomatic non-pregnant women of reproductive age at a tertiary care hospital, Vietnam

BackgroundVaginal candidiasis is frequent in women of reproductive age. Accurate identification Candida provides helpful information for successful therapy and epidemiology study; however, there are very limited data from the Vietnam have been reported. This study was performed to determine the prevalence, species distribution of yeast causing vaginal discharge and antifungal susceptibility patterns of Candida albicans among symptomatic non-pregnant women of reproductive age.MethodsVaginal discharge samples were collected from 462 women of reproductive age in Hanoi, Vietnam between Sep 2019 and Oct 2020. Vaginal swabs from these patients were examined by direct microscopic examination (10% KOH). CHROMagar™ Candida medium and Sabouraud dextrose agar supplemented with chloramphenicol (0.5 g/l) were used to isolate yeast, and species identification was performed using morphological tests and molecular tools (PCR and sequencing). Antifungal susceptibility testing was determined according to the Clinical and Laboratory Standards Institute guidelines (M27-A3 and M27-S4).ResultsThe prevalence of vaginal yeast colonization in non-pregnant women was 51.3% of 462 participants. Nine different yeast species were identified. Among these isolates, C. albicans (51.37%) was the most frequent, followed by C. parapsilosis (25.88%), C. glabrata (11.37%), C. tropicalis (4.31%), C. krusei (3.92%), C. africana (1.57%), Saccharomyces cerevisiae (0.78%), C. nivariensis (1 isolates, 0.39%), and C. lusitaniae (1 isolates, 0.39%), respectively. Among C. albicans, all 46 isolates were 100% susceptible to micafungin, caspofungin, and miconazole. The susceptibility rates to amphotericine B, 5-flucytosine, fluconazole, itraconazole and voriconazole were 95.65, 91.30, 91.30, 82.61 and 86.95%, respectively.ConclusionsThe prevalence of VVC among symptomatic non-pregnant women of reproductive age in Vietnam was higher than many parts of the world. The high frequency of non-albicans Candida species, which were often more resistant to antifungal agents, was a notable feature. Resistance rates of vaginal C. albicans isolates to antifungal agents was low. Our findings suggest that continued surveillance of changes in species distribution and susceptibility to antifungals should be routinely screened and treated.

The antifungal susceptibility of Candida albicans isolated from HIV/AIDS patients

Background: Candida albicans was found to be dominant in patients with human immunodeficiency virus / acquired immunodeficiency syndrome (HIV/AIDS). The antifungals fluconazole, ketoconazole, and nystatin were used as oral candidiasis therapy for HIV/AIDS, each of which has differing susceptibility in oral candidiasis therapy. Purpose: The present study aimed to evaluate the susceptibility and antifungal resistance to oral C. albicans in HIV/AIDS patients. Methods: The subjects followed the universal precaution principles. Oral Candida species were isolated from the saliva of 98 HIV/AIDS subjects. Identification of Candida species was carried out by the mycobiotic agar of API 20 C Aux system. Susceptibility and resistance antifungal tests on the Candida species were performed using a Fungus ATB Kit. Results: Candida albicans was the most dominant species found from 98 subjects (95%). The rest were other Candida species. There are 41 subjects (42%) with a history of oral candidiasis, and 57 subjects (58%) without. The history of those who used antifungals were: nystatin = 60 subjects (61%), fluconazole = 39 subjects (40%), and ketoconazole = two subjects (2%). These antifungals have a susceptibility above 80% against C. albicans, except the nystatin group (79%) (p&gt;0.05; 0.628), but fluconazole has a strong correlation (r=0.820) to susceptibility, susceptibility-dependent dose, and resistance. Conclusion: Candida albicans was dominant in the saliva of HIV/AIDS patients. This fungus was effectively treated by fluconazole, ketoconazole and nystatin. These antifungals had a high susceptibility at ≤ 8 μg/mL to C. albicans.

Prevalence, virulence and antifungal activity of C. albicans isolated from infected root canals

BackgroundThere is limited data on the prevalence of Candida species in infected root canal systems of human teeth. We attempted to investigate the prevalence, genotype, virulence and the antifungal susceptibility of Candida albicans isolated from infected root canals of patients with primary and post-treatment infections in a UAE population.MethodsMicrobiological samples from 71 subjects with infected root canals were aseptically collected, and cultured on Sabouraud dextrose agar, and C. albicans was identified using multiplex polymerase chain reaction, and the isolates were further subtyped using ABC genotyping system. Their relative virulence was compared using further four archival samples of endodontic origin from another geographical region, and four more salivary isolates, as controls. The virulence attributes compared were biofilm formation, and production of phospholipase and haemolysin, and the susceptibility to nystatin, amphotericin B, ketoconazole, and fluoconazole was also tested.Results4 out of 71 samples (5.6%) yielded Candida species. On analysis of variance among the groups, the intracanal isolates, mainly Genotype A, possessed a high degree of phospholipase and haemolysin activity (p < 0.05). The UAE and Finland isolates were stronger biofilm formers and had superior phospholipase production capacity compared with the salivary isolates. All isolates were sensitive to the antifungal chemicals used. The salivary isolates were more sensitive to fluoconazole compared to other groups (p < 0.05).ConclusionThe prevalence of C. albicans in infected root canals of patients attending a dental hospital in UAE is low. The strains isolated were good biofilm formers, possessed strong phospholipase and haemolysin activity and were mostly of the genotype A. The fact that the root canal isolates possessed significant hydrolase activity, imply that they are equipped with virulence attributes necessary for survival within a harsh intracanal ecosystem.

Virulence and in vitro antifungal susceptibility of Candida albicans and Candida catenulata from laying hens

In spite of evidence that domestic and wild birds may act as carriers of human pathogenic fungi, data on the role of laying hens as reservoirs of drug resistant and virulent yeasts is lacking. Here, we assess several virulence factors (phospholipase and haemolysin activity) and the antifungal susceptibility profiles of 84 Candida albicans and 17 Candida catenulata strains isolated from cloacae (group A), faeces (group B) and eggs (group C) of laying hens. Of these strains, 95% C. albicans and 23% C. catenulata strains displayed phospholipase and haemolytic activities. For C. albicans, the highest values of phospholipase (Pz = 0.62) and haemolytic activities (Hz = 0.49) were recorded among the strains from group C whilst for C. catenulata (Pz = 0.54; Hz = 0.49) among those from group A. High minimum inhibitory concentration (MIC) values for azoles and amphotericin B (AmB) were recorded irrespective of their sources in all C. albicans strains. A total of 22 C. albicans strains were multidrug resistant, displaying resistance to fluconazole, itraconazole (ITZ), voriconazole (VOR) and posaconazole (POS). All C. catenulata strains from group C were resistant to ITZ, POS, micafungin and anidulafungin and susceptible to AmB. In this study, C. albicans and C. catenulata isolated from the cloacae, faeces and eggs of laying hens produced phospholipase and haemolysin and might be multidrug resistant. In the environment (faeces) or in eggs, C. albicans and C. catenulata strains might acquire pathogenic virulence traits and/or show multidrug resistance profiles. Based on these results, breeding and handling of laying hens and/or eggs may have implications for human and animal health.

Prevalence and antifungal susceptibility of Candida albicans causing vaginal discharge among pregnant women in Lebanon

BackgroundVaginal candidiasis is frequent in pregnant women and is associated with sepsis and adverse neonatal outcomes. This study determined the prevalence of candida species in symptomatic pregnant women and evaluated the antifungal susceptibility profile of the isolated Candida strains. It also aimed to explore whether Candida species predicts gestational complications and adverse neonatal outcomes.MethodsA total of 258 pregnant women with vaginal discharge at 35 to 37 week of gestation participated in this study. Vaginal swabs from these patients were collected at various obstetrics and gynecology clinics in Lebanon for a period of 14 months. Candida isolates were identified at species level and antifungal susceptibility of Candida albicans to fluconazole (FCZ), amphotericin B (AMB), itraconazole (ICZ) and voriconazole (VCZ) was determined by the agar-based E-test method.ResultsAmong 258 women tested, 100 (39%) were positive for Candida species. C. albicans, C. glabrata and C. krusei were isolated from 42, 41 and 17% of the women, respectively. C. albicans was significantly associated only with gestational diabetes while C. krusei or C. glabrata had significant positive associations with other gestational complications. The antifungal susceptibility tests of C. albicans isolates revealed 97.5, 90, 87.5 and 97.5% susceptibility to AMB, FCZ, ICZ and VCZ, respectively.ConclusionThe current study revealed high incidence of both C. albicans and non-C. albicans Candida strains causing vulvovaginitis among pregnant women in Beirut, Lebanon. Candida screening as antenatal follow up is advised to minimize the risk of adverse neonatal outcome or gestational complications.

Antifungal Susceptibility of Candida albicans Isolates at a Tertiary Care Hospital in Bulgaria

Background: The precise identification of yeasts and their antifungal sensitivity is a key factor in the choice of a suitable drug for treatment and prevention of fungal infections. Objectives: The aim of the present study was to determine in vitro susceptibility of clinical Candida albicans isolates to nine antifungal agents. Methods: A total of 61 C. albicans isolates were tested. Antifungal susceptibility was evaluated by determination of minimum inhibitory concentrations (MIC). Results: Fifty C. albicans isolates were susceptible to nine antifungal agents. The remaining 11 yeasts were resistant to one or more antifungals. All C. albicans were susceptible to amphotericin B with MICs 0.25 to 1 μg/mL and exhibited sensitivity to 5-fluorocytosine with MIC90 of 0.125 μg/mL. The MIC50 and MIC90 of fluconazole were 0.5 and 32 μg/mL, whereas the MIC50 and MIC90 of voriconazole were considerably lower - 0.0078 and 2 μg/mL. The isolates showed susceptibility to echinocandins with MIC90 of micafungin, anidulafungin and caspofungin of 0.015, 0.031, and 0.125 μg/mL, respectively. Of particular interest was detection of seven C. albicans isolates, which expressed a high-level resistance to all azoles and one of them was also resistant to echinocandins. Conclusions: In conclusion, detection of resistance in C. albicans, which is a species typically susceptible to antifungals, is of great importance for clinical practice.

Analysis of the distribution and antifungal susceptibility of Candida albicans and non-albicans Candida isolated from human blood culture

Analysis of the distribution and antifungal susceptibility of Candida albicans and non-albicans Candida isolated from human blood culture

Genetic diversity and antifungal susceptibility of Candida albicans isolated from Iranian patients

A total of 105 independent Candida albicans strains isolated from patients in Iran were investigated. According to CLSI documents M27-A3 and M27-S4, the 24 h geometric mean MICs of caspofungin, itraconazole, and fluconazole were 0.27, 3.19, and 11.91μg/ml, respectively. Microsatellites analysis of CEF3, CAIII, LOC4 Loci identified 93 different allelic genotypes clustered apart into six different clades. Antifungal susceptibility was not linked with the source of isolation and the corresponding genotype of C. albicans strains.

Effect of Saccharomyces boulardii Extract on SAP2 Gene Expression and Antifungal Susceptibility of Candida albicans

Background: Saccharomyces boulardii, a non-pathogenic yeast, is effective on prevention and treatment of intestinal infections caused by bacterial pathogens and also affects the virulence factors of Candida albicans. SAP2, an important potential virulence factor of C. albicans is a suitable target for a new research. Objectives: The current study aimed at investigating the effect of S. boulardii extract on the expression of SAP2 gene and antifungal susceptibility of C. albicans isolates. Methods: The current study investigated SAP2 relative expression and antifungal susceptibility patterns of C. albicans species isolated from oral lesions of HIV+ patients and the standard strain ATCC 10231 after exposure to S. boulardii extract. Susceptibility of C. albicans isolates to antifungal drugs was assessed according to those proposed in the clinical and laboratory standards institute (CLSI) M44-A2 reference method. The real-time polymerase chain reaction (PCR) was performed to evaluate SAP2 gene expression. Results: Saccharomyces boulardii extract 0.48 mg/mL changed the antifungal susceptibility pattern of C. albicans isolates to ketoconazole and itraconazole. Before exposure, 53.3% of the isolates were sensitive to ketoconazole, while it increased to 73.3% after exposure to S. boulardii extract. The sensitivity to itraconazole increased from 6.7% to 26.7% after exposure to S. boulardii extract. Although susceptibility of C. albicans isolates to other antibiotics (fluconazole, clotrimazole, nystatin, and amphotericin-B) did not change after exposure to S. boulardii extract, there was a significant difference in the average inhibitory zones of the isolates after exposure to S. boulardii extract. Conclusions: The level of SAP2 expression significantly reduced in the isolates treated with 0.48 mg/mL S. boulardii extract. Comparison of SAP2 gene expression between ketoconazole-resistant and -intermediate isolates, and the ketoconazole-sensitive ones demonstrated the relative higher gene expression in resistant and intermediate isolates. Saccharomyces boulardii extract can be considered as a suitable probiotic candidate to prevent and treat C. albicans infections.

Prevalence and antifungal susceptibility of Candida albicans and its related species Candida dubliniensis and Candida africana isolated from vulvovaginal samples in a hospital of Argentina

Candida africana taxonomical status is controversial. It was proposed as a separate species within the Candida albicans species complex; however, phylogenetic analyses suggested that it is an unusual variety of C. albicans. The prevalence of C. albicans-related species (Candida dubliniensis and C. africana) as vulvovaginal pathogens is not known in Argentina. Moreover, data on antifungal susceptibility of isolates causing vulvovaginal candidiasis is scarce. The aims of this study were to establish the prevalence of C. dubliniensis and C. africana in vaginal samples and to evaluate the antifungal susceptibilities of vaginal C. albicans species complex strains. We used a molecular-based method coupled with a new pooled DNA extraction methodology to differentiate C. dubliniensis and C. africana in a collection of 287 strains originally identified as C. albicans isolated from an Argentinian hospital during 2013. Antifungal susceptibilities to fluconazole, clotrimazole, itraconazole, voriconazole, nystatin, amphotericin B and terbinafine were evaluated by using the CLSI M27-A3 and M27-S4 documents. Of the 287 isolates, 4 C. dubliniensis and one C. africana strains (1.39% and 0.35% prevalence, respectively) were identified. This is the first description of C. africana in Argentina and its identification was confirmed by sequencing the ITS2 region and the hwp1 gene. C. dubliniensis and C. africana strains showed very low MIC values for all the tested antifungals. Fluconazole-reduced-susceptibility and azole cross-resistance were observed in 3.55% and 1.41% of the C. albicans isolates, respectively. These results demonstrate that antifungal resistance is still a rare phenomenon in this kind of isolates.

In vitro Antifungal Susceptibility of Candida albicans Isolates from Patients with Chronic Periodontitis and Diabetes

Alterations that lead to deficiency of the immune system, such as diabetes mellitus, may promote proliferation of Candida albicans and selection of strains which have greater ability to adhere and to penetrate the host tissues. Recent studies indicate an increase of the antifungal resistance of C. albicans isolates in periodontal pockets, suggesting that the oral cavity could be a reservoir of resistant yeast to antifungal agents. Moreover, oral cavity can act as a reservoir of certain pathogens that may cause systemic infections. The periodontal pocket is an ecological niche suitable to host microorganisms that could act as opportunistic pathogens. The aim of this study is to contribute to the understanding of resistance to conventional antifungal against C. albicans isolates from patients with periodontitis and diabetes. The determination of the minimal inhibitory concentrations (MIC) was evaluated according to M27S3 of the CLSI (2008), with modifications. The results showed that 48.8% of the studied strains were resistant to one or more antifungals and 6.6% were resistant to fluconazole and voriconazole. These results suggest an increasing resistance to conventional antifungal agents among Candida species, suggesting that the oral cavity could host pathogen fungi.

Effect of filamentation and mode of growth on antifungal susceptibility of Candida albicans

Biofilm formation involving profuse hyphal growth is a major characteristic of Candida spp. and confers higher antifungal resistance than its planktonic mode of growth. We investigated the antifungal susceptibility of Candida albicans and its hyphal mutants (Δ efg1/ efg1, Δ cph1/ cph1 and ΔΔ cph1/ cph1 efg1/ efg1) to commonly used antifungals during planktonic, adhesion and biofilm modes of growth. The minimum inhibitory concentration (MIC) of each antifungal agent was determined for a lower inoculum (1 × 10 3 cells/mL) and higher inoculum (1 × 10 7 cells/mL) of planktonic Candida. Furthermore, MICs of C. albicans biofilms and adhesion modes of growth were determined with a standard XTT assay. Candida albicans in adhesion and biofilm modes of growth, but not in planktonic mode, were resistant to all five antifungal agents tested. Although Δ efg1/ efg1 and ΔΔ cph1/ cph1 efg1/ efg1 mutants formed less biofilm than wild-type C. albicans SC5314, they were similarly resistant to caspofungin. However, these mutants were more sensitive to amphotericin B and nystatin than the wild-type. Adhesion per se confers increased resistance to antifungal agents, which is further pronounced in the biofilm mode of Candida. Filamentation does not appear to be a major determinant of the antifungal resistance in Candida biofilms.

Molecular Differentiation and Antifungal Susceptibility of Candida albicans Isolated from Patients with Respiratory Infections in Guiyang Medical College Hospital, China

Genetic heterogeneity and drug susceptibility patterns of 43 Candida albicans isolates from patients with respiratory infections in China were compared with those of 52 isolates from Japanese patients. Of the 43 strains, 17 were genotype A, 17 were genotype B, 8 were genotype C, and 1 was genotype E. Drug susceptibilities against amphotericin B, flucytosine, 3 azoles, and micafungin of the 43 strains and the 52 Japanese isolates were compared. All strains in China were susceptible to all drugs tested, and susceptibility patterns of the two countries were similar. Four Japanese isolates showed trailing growth for azole antifungals; Chinese strains did not.

Antifungal susceptibility of Candida albicans biofilms on titanium discs with different surface roughness

Although it is well known that fungal biofilms have increased resistance to antimicrobial agents, limited information is available on the formation of candidal biofilms on implant surfaces with different surface roughness and their resistance to conventional antifungal therapy. In the current study, the effect of increasing the surface roughness of titanium discs on the susceptibility of Candida albicans biofilms to amphotericin B was determined. Grade I commercially pure titanium discs were sandblasted with 99.6% aluminium oxide of different grit sizes, producing surface roughness of 0.90, 1.88 and 3.82 microm (Groups A, B and C), respectively (P < 0.001). The antifungal susceptibility of C. albicans biofilm grown on different Ti discs was determined using XTT assay. The 50% reduction in metabolic activity (50% RMA) of planktonic C. albicans (0.5 microg/mL) was much lower than those from Groups A, B and C (2, 16, 2 microg/mL, respectively), while the 50% RMA from Group B was three-fold higher than those from Groups A and C. In conclusion, difference in titanium surface roughness was associated with variations in the antifungal resistance of the candidal biofilm. Group C appeared to have an optimum surface roughness for biofilm resistance.

Antifungal susceptibility of Candida albicans isolated from oral mucosa of patients with cancer

The increasing number of oral infections due to opportunistic fungi in immunocompromised patients, needs a new evaluation of the drugs in use. The susceptibility in vitro of Candida albicans strains from the oral mucosa of cancer patients to amphotericin B, ketoconazole, miconazole, fluconazole and itraconazole were evaluated. A dilution technique in YNB agar or subculture on Sabouraud agar was utilised for MIC or MFC determinations. With this methodology, the best fungicidal drug for C.albicans collected from the oral mucosa of 40 cancer patients, divided in two groups: one treated by radiotherapy and the other not, the best results were obtained with amphotericin B, presenting low values of MIC compared to azoles and MFC values. However it is important to take into consideration the utilisation in vivo of this polyenic antibiotic and the possible toxic levels necessary to achieve good results. The coexistence of other fungi and the local conditions must also be pondered with these patients, who are mostly undergoing radiotherapy. In order to achieve better results without undesirable consequences, higher levels of MIC are expected with the daily clinical use of new drugs.

Evaluation of the E test for fluconazole susceptibility testing of Candida albicans isolates from oropharyngeal candidiasis.

The aim of the present study was to evaluate the utility of the E test in determining the antifungal susceptibility of Candida albicans. Reproducibility of the E test was determined for amphotericin B, fluconazole, and itraconazole using three different solid media: RPMI 1640, Casitone, and yeast nitrogen base agar. Minimum inhibitory concentrations (MICs) were comparable (results at +/- 2 dilutions) in 92% of the tests for amphotericin B and in 100% for fluconazole and itraconazole. Determination of MIC endpoints was easiest on Casitone agar. Candida albicans isolates from 23 patients undergoing fluconazole therapy for oropharyngeal candidiasis were tested for fluconazole susceptibility. Good correlation was obtained between the MICs of fluconazole and clinical outcome. Clinical failure was associated with strains for which MICs were > or = 48 micrograms/ml. These results suggest that the E test has potential utility for fluconazole susceptibility testing of clinical yeast isolates.