ATB Fungus Research Articles

Antifungal susceptibility profile and local epidemiological cut-off values of Yarrowia (Candida) lipolytica: an emergent and rare opportunistic yeast.

Yarrowia lipolytica, also known as Candida lipolytica, is an emerging opportunistic "rare pathogenic yeast". Due to the limited data on its antifungal susceptibility, the clinical treatments become challenging. Based on the China Hospital Invasive Fungal Surveillance Network (2009-2022), we conducted a comprehensive multi-method study on clinical isolates from various central hospitals. This study is currently the largest study carried out to assess the antifungal susceptibility of Y. lipolytica. It is also the first to establish local epidemiological cut-off values (L-ECOFFs), identify its ERG11 mutations, and assess the consistency between the three prevalent commercial antifungal susceptibility testing methods and the broth microdilution method. We recommend the Sensititre YeastOne as the best option for antifungal susceptibility testing for Y. lipolytica, followed by the ATB FUNGUS 3. Nevertheless, practitioners should use the MIC test strip with discretion.

Spectrum and Antifungal Susceptibility Profiles of Candida Species Causing Vulvovaginitis in Lomé, Togo—Candida vaginitis and species involved in Lomé (Togo)

Background: Vulvovaginal infections are common in women. In Togo’s medical biology laboratories, routine diagnosis is often limited to filamentation testing, and the identification of fungal species is rarely performed. The aim of this study was to update the spectrum of Candida species isolated in vulvovaginitis and to determine their antifungal susceptibility profiles. Methods: Cross-sectional analytical study was carried out in women presenting leukorrhea received in two public laboratories in Lomé from June 2015 to October 2015. Socio-demographic and clinical data were collected through a structured questionnaire during an individual interview. Vulvovaginal samples were cultured in Sabouraud dextrose agar with chloramphenicol. Identification of fungi was determined by filamentation test and API 20C AUX® gallery. The antifungal susceptibility profile was performed on five antifungal agents by a semi-solid medium microdilution technique of the ATB Fungus 3® gallery. Results: Candida albicans/dubliniensis/africana complex was isolated in 51.6% of cases by API 20C AUX® gallery. The same species were isolated by filamentation test in 12.3% of cases. All Candida species identified were sensitive to Voriconazole, whereas four species including Candida albicans/dubliniensis/africana complex had variable sensitivities compared to the five antifungal agents tested. Conclusions: This study demonstrated a high distribution of non-albicans species of Candida in Togo. Empirical treatment of candidiasis could contribute to increasing antifungal resistance. Routine fungi identification, at least by using an auxanogram test, could be instituted in medical laboratories to improve the therapeutic management of these diseases.

Comparative Analysis of Epidemiological and Clinical Characteristics Between Invasive Candida Infection versus Colonization in Critically Ill Patients in a Tertiary Hospital in Anhui, China.

ObjectiveInvasive infections due to Candida spp. have unique epidemiology, strain distribution, antimicrobial susceptibility, and clinical features. This study aimed to compare and evaluate these characteristic variables between invasive Candida infection and colonization of critically ill patients in local China to potentially improve differential diagnosis and therapy.MethodsA total of 193 critically ill patients were recruited and followed up for the study, and 133 Candida isolates were obtained from invasive Candida-infected or -colonized subjects. The strains were identified to species level through matrix-assisted laser desorption/ionization–time-of-flight mass spectrometry, assisted by DNA sequencing. Candida susceptibility to common antifungals, including azoles, was determined by microbroth ATB Fungus 3 methodology. Azole resistance–related gene sequencing and homologous 3D-structure modeling were employed. Patient demographics and clinical risk factors were documented and comparatively analyzed from the hospital information-management system.ResultsNon–C. albicans Candida (56%) principally caused invasive Candida infections, while C. albicans (55.17%) contributed more to Candida colonization in critically ill patients. Additional risk factors exerted significant impact on both Candida cohorts, primarily including invasive interventions, cancers, and concurrent infections in common. Most colonized Candida spp. harbored relatively higher sensitivity to azoles. ERG11 gene mutations of T348A and A1309G, A395T and C461T, and a novel G1193T to our knowledge were identified in azole-resistant C. albicans, C. tropicalis, and C. parapsilosis respectively, and their corresponding homologous 3D-structure modeling was putatively achieved.ConclusionDistinct epidemiological and clinical characteristics existed between invasive Candida infection and colonization in critically ill patients. Multiple risk factors significantly involved both the Candida cohorts. Colonized Candida exhibited generally higher azole sensitivity than invasively infectious counterparts. ERG11 point mutations had mechanistically potential ties with local Candida resistance to azoles.

Validation of the commercial method ATB FUNGUS 3 against the reference method M27-A2, to determine the susceptibility of Candida albicans to different antifungals

El aumento de la incidencia de las micosis ha generado la necesidad de desarrollar técnicas in vitro para el estudio de la susceptibilidad a los antifùngicos; El documento CLSI M27-A2 es el método de referencia para estudios de sensibilidad en levaduras. No obstante, este no subsana las necesidades de rutina de los laboratorios, principalmente por ser laboriosos; en consecuencia, métodos alternativos surgen ante la necesidad de contar con técnicas más sencillas, una de ellos es el ATB FUNGUS 3 que permite determinar la sensibilidad de Candida frente a diferentes antifùngicos. Objetivo: Validar el método comercial ATB FUNGUS 3, frente al método de referencia M27-A2, con el fin de conocer su valor diagnóstico Material y métodos: Se determinó la eficacia del método a través de parámetros de test diagnóstico; además, se evaluó la sensibilidad de 50 cepas de Candida albicans frente a Fluconazol (FLZ) e Itraconazol (ITZ) mediante el método comercial y el de referencia. Resultados: Se encontró que el ATB - FUNGUS 3 presenta una especificidad para FLZ de 100 %, sensibilidad de 91%, valor predictivo positivo (VPP) de 56%, valor predictivo negativo (VPN) de 100%, con una eficacia diagnóstica de 92%, calculados para un intervalo de confianza (IC) de 95%; para ITZ la especificidad y sensibilidad fue de 88 % y 90% respectivamente, con un VPP de 64%, un VPN de 97%, eficacia diagnóstica de 90%, IC 95%. Para las pruebas de concordancia, el índice Kappa para FLZ e ITZ fue de 0,67 y 0,68 respectivamente. La prueba de Likelihood ratio para el FLZ fue (LR+) de 11,25 mientras que el (LR-) fue 0; para el ITZ (LR+) de 9,19 y el (LR-) fue 0,14. Reproducibilidad de 90 % (FLZ) y 85% (ITZ). Conclusiones: El ATB FUNGUS 3, es una técnica rápida, de fácil realización y reproducible; pero el desempeño global de la técnica, sugiere que aún no es confiable para el diagnostico en laboratorios, debido a los valores bajos obtenidos en los VPP, que indican que se podría derivar en errores al momento de determinar una cepa como sensible o resistente, punto importante al momento de decidir la conducta terapéutica.

MALDI-TOF MS Overcomes Misidentification of the Uncommon Human Pathogen Candida famata by Routine Phenotypic Identification Methods.

Candida famata has been associated with the identifiable Candida infections that takes place in human and the identification error of this species possibly will result in misinterpretation of antifungal susceptibility and improper diagnosis; which will have a major effect on the prognosis and therapy of patients. Our objective is to correctly identify Candida spp. collected from patients at the intensive care units, New Cairo University teaching hospital in Cairo-Egypt using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). Hundred clinically isolated yeast strains were identified using API 20C AUX obtained from patients receiving care at intensive care units. ATB FUNGUS 3strips were used to detect the minimum inhibitory concentration. Thirty-three non duplicate strains identified as C. famata were subjected to re-identification by MALDI-TOF MS. Our results revealed that isolates were initially identified as C. famata 33%, C. tropicalis 15%, C. albicans12% and C. parapsillosis 10% using the phenotypic techniques. MALDI-TOF MS analyses results showed that the 33 C. famata isolates are C. tropicalis (n = 29), Trichosporon asahii (n = 2), C. parapsilosis (n = 1), and Aeromonas sobria (n = 1). Antifungal resistance was low in the Candida species, except for reduced susceptibility to itraconazole among C. krusei strains. This report shows that misidentification of C. famata is frequent when using conventional phenotypic methods of identification which result in challenges in treating fungal infections. MALDI-TOF MS is an accurate convenient substitute to classical approaches for fungal identification. In general, antifungal multidrug resistance is uncommon in our studied Candida species and yeast isolates.

Distribution of clinical Candida species and their susceptibility to antifungal agents

Background: The incidence of fungal infections, especially by Candida species, has increased in recent years. This study was designed to isolate and identify Candida species from various clinical samples, and to examine their susceptibility to antifungal agents. Methods: A total of 175 Candida species were isolated from different clinical samples, and were identified using germ tube test, Cornmeal agar, and API C 20 AUX and VITEK 2 Compact Systems. Antifungal susceptibility of these isolates was determined using ATB Fungus 3 strip and VITEK 2 antifungal susceptibility cards. The results of these two methods were comparatively assessed. Results: A total of 175 Candida strains were isolated from 114 (65.1%) urine, 42 (24%) blood, eight (4.6%) sputum, seven (4%) endotracheal, and four (2.3%) wound samples. Of isolated Candida species, 102 (58.2%) were Candida albicans, 31 (17.6%) Candida tropicalis, 17 (9.6%) Candida parapsilosis, 13 (7.4%) Candida glabrata, three (1.8%) Candida kefyr, three (1.8%) Candida krusei, two (1.2%) Candida lusitaniae, and one (0.6%) Candida famata. By VITEK 2 antifungal susceptibility cards, the overall resistance rates were 0.6% to each of amphotericin B and 5-flucytosine, and 1.8% to fluconazole. In ATB Fungus 3 strip, the resistance (1.8%) was observed only to fulconazole. All isolates were uniformly susceptible to voriconazole in both methods. Conclusion: Valuable information and data on distribution and susceptibility of Candida strains were obtained. These data may be valuable from epidemiological point of view as well as for proper and optimal therapy of Candida infections in our region (Şanliurfa, Turkey).

Antifungal Resistance Profile for Clinical Isolates of Candida spp. at Institute Pasteur of Côte d’Ivoire

Background: The aim of this study was to identify Candida species isolated from clinical samples and detect their susceptibility patterns to antifungal agents. Methodology: This study was conducted on clinical samples collected from patients with suspected candida infection referring to mycology laboratory of Institute Pasteur of Côte d’Ivoire for diagnosis. Candida species were isolated and identified using conventional and the innovative VITEK 2 microbial identification system. Antifungal susceptibility test for Amphotericin-B, 5-Flucytosine, Fluconazole, Itraconazole and Voriconazole were performed using ATB Fungus 3® of Biomerieux. Results: Most of the isolates were obtained from vaginal swabs 806 (64.8%), followed by Nail scrapings 49 (5.67%). Overall C. albicans counting was 58.9% (732/1234) of the infections. Sensitivity rates of C. albicans species from vaginal swab to 5-FC, AMB, FCZ, VCR and ITR were 97.26, 94.34, 94.89, 95.98 and 88.69 respectively. Resistance rates of C. albicans from vaginal swab were observed with AMB (5.66%) and ITR (5.29%). Sensitivity rate of C. glabrata was 100% with 5-FC, AMB and VCR. All C.krusei species were resistant to fluconazole. The sensitivity rate of C. tropicalis to the antifungal drugs tested varied between 91.66% with ITR to 100 with VCR. Conclusion: C. albicans was the most common of the candida species isolated in this study and remains sensitive to the drugs tested. The study showed resistance of all C. krusei strains to fluconazole. Knowledge about etiologic agents and their susceptibility patterns is helpful for successful treatment of the patients.

Pathogenicity and drug-resistance analysis of Candida glabrata in patients with oral candidiasis

Objective: To investigate the detection rate, population features and in vitro antifungal drug susceptibility of Candida glabrata in patients with oral candidiasis. Methods: The saliva fungi culture cases and the ratio of Candida glabrata in patients with oral candidiasis were analyzed during 2014-2018. Fungal species were identified by CHROMagar Candida chromogenic medium and API 20C AUX yeast identification kit. Sixty strains with cfu≥200/ml were collected and performed the in vitro antifungal susceptibility tests by using ATB FUNGUS 3 susceptibility kit. Results: The number of patients with oral candidiasis was 12 401 and the ratio of Candida glabrata was 3.44% (427/12 401) from 2014 to 2018. The positive ratio of infection increased with age increasing.The positive rate of female aged 41 to 50 years old began to increased. Female aged more than 50 years old subgroups demonstrated the tendency towards increased positive rates with increasing age. It was found out through clinical data analyzing that the patients with oral candidiasis were the most and oral lichen planus, Sjögren's syndrome and xerostomia carrying high quantity ratios of infection. Candida glabrata had highest resistance(8.3%) to the fluconazole, 6.7% of the isolates were of non-WT phenotype to itraconazole and voriconazole, all of the isolates were of WT phenotype to amphotericin B. Conclusions: The ratio of infection in the patients with oral candidiasis increased with age increasing and the olders are susceptible to infection. Candida glabrata has a certain resistance to azoles and clinically reasonable use of antifungal drugs according to the results of drug susceptibility is very important.

Clinical and microbiological characteristics of Cryptococcus gattii isolated from 7 hospitals in China

BackgroundInfection, even outbreak, caused by Cryptococcus gattii (C. gattii) has been reported in Canada and the United States, but there were sparsely-reported cases of C. gattii in China. Our interest in occurrence, clinical manifestation, laboratory identification and molecular characterization of Chinese C. gattii strains leads us to this research.ResultsOut of 254 clinical isolates, initially identified as Cryptococcus neoformans (C. neoformans), eight strains were re-identified as C. gattii. Multi-locus sequence typing (MLST) showed genotype VGI accounted for the most (6 / 8), the other two strains were genotype VGII (VGIIa and VGIIb respectively) with 3 specific spectra of molecular weight about 4342, 8686, 9611 Da by MALDI-TOF MS. The minimal inhibitory concentrations (MICs) of Fluconazole with Yeast one was 2~4 times higher than that with ATB fungus 3 and MICs of antifungal agents against VGII strains were higher than against VGI strains. Comparative proteome analysis showed that 329 and 180 proteins were highly expressed by C. gattii VGI and VGII respectively. The enrichment of differentially expressed proteins was directed to Golgi complex.ConclusionsInfection by C. gattii in China occurred sparsely. Genotype VGI was predominant but VGII was more resistant to antifungal agents. There was significant difference in protein expression profile between isolates of VGI and VGII C. gattii.

ALDH1A3 Regulations of Matricellular Proteins Promote Vascular Smooth Muscle Cell Proliferation.

SummaryVascular smooth muscle cell (VSMC) proliferation promotes intimal hyperplasia (IH) in occluding vascular diseases. Here we identified a positive role of ALDH1A3 (an aldehyde dehydrogenase) in this pro-IH process. The expression of ALDH1A3, but not that of 18 other isoforms of the ALDH family, was substantially increased in cytokine-stimulated VSMCs. PDGF(BB) stimulated VSMC total ALDH activity and proliferation, whereas ALDH1A3 silencing abolished this effect. ALDH1A3 silencing also diminished the expression of two matricellular proteins (TNC1 and ESM1), revealing a previously unrecognized ALDH1A3 function. Loss-of-function experiments demonstrated that TNC1 and ESM1 mediated ALDH1A3's pro-proliferative function via activation of AKT/mTOR and/or MEK/ERK pathways. Furthermore, ALDH inhibition with disulfiram blocked VSMC proliferation/migration in vitro and decreased TNC1 and ESM1 and IH in angioplasty-injured rat carotid arteries. Thus, ALDH1A3 promotes VSMC proliferation at least partially through TNC1/ESM1 upregulation; dampening excessive ALDH1A3 activity represents a potential approach to IH mitigation.

Mechanisms of azole resistance in clinical isolates of Candida glabrata from two hospitals in China.

Purpose: Candida glabrata has emerged as the second or third most common non-albicans species responsible for an increasing number of systemic infections. Moreover, its high-level of resistance to azole is associated with a high mortality rate. This study aimed to evaluate nosocomial infections and resistance characteristics of C. glabrata and to explore the mechanism of azole resistance in C. glabrata.Patients and methods: Fifty-nine clinical C. glabrata isolates were collected from two hospitals in China. The susceptibility of the strains to antifungal agents was determined by both the ATB Fungus 3 strip and CLSI M27 broth microdilution method. Efflux of rhodamine 6G was examined to evaluate the effects of efflux pumps. The expression levels of CgCDR1, CgCDR2, CgSNQ2, CgERG11, and CgPDR1 were examined by real-time PCR. The sequences of CgERG11 and CgPDR1 were determined by PCR-based DNA sequencing.Results: All 59 isolates of C. glabrata were susceptible to flucytosine and amphotericin B. Twelve (20.3%) isolates were determined to be fluconazole-resistant, whereas 13 (22.0%) and 27 (45.7%) isolates were categorized as non-wild-type for itraconazole and voriconazole, respectively. Efflux pumps in azole-resistant isolates showed stronger effects than those in azole-susceptible-dose dependent isolates, which is consistent with the significant upregulation of CgCDR1 and CgCDR2 (P<0.05), whereas no obvious differences were found for CgSNQ2, CgERG11, and CgPDR1 (P>0.05). Sequencing of CgERG11 showed no alteration favoring the hypothesis that CgERG11 is not involved in the azole resistance of C. glabrata. Four CgPDR1 missense mutations were found in azole-resistant isolates, of which the high frequency of the CgPDR1 mutation, A848V, has not been reported previously.Conclusion: Efflux pump function is the main mechanism of resistance to fluconazole in our collected clinical isolates of C. glabrata, and further studies of the related gene disruption and genome-wide expression are needed to verify the function.

Distribution and antibiotic resistance of 532 bacterial panthogens in blood culture in a hematology department

Objective To analyze the distribution and antibiotic resistance of bacterial pathogens in blood culture in the Department of Hematology of the First Affiliated Hospital of Nanjing Medical University from 2013 to 2017. Methods BACTEC FX automatic blood culture instrument was used for blood culture. VITEK-2 Compact automatic microbial identification and drug susceptibility system was used for bacterial identification, drug sensitivity testing and fungal identification. K-B and ATB FUNGUS 3 methods were used for Streptococcus and fungi susceptibility testing, respectively. WHONET5.6 software was used for statistical analysis. Results The positive results of blood culture accounted for 7.6% during 2013 to 2017 and the top five isolated pathogenic bacteria were Escherichia coli (20.9%), Klebsiella pneumoniae (18.0%), coagulase negative Staphylococcus (12.4%), Pseudomonas aeruginosa (11.5%) and Enterobacter cloacae (3.6%). Carbapenems (94.4%) were the most active antibiotics against Enterobacteriaceae. Pseudomonas aeruginosa strains were sensitive to all antibacterial dugs except aztreonam. Acinetobacter baumannii strains had a lower sensitivity to almost all antibacterial dugs. Vancomycin, linezolid and teicoplanin were active antimicrobial agents against gram-positive cocci. Conclusion Patients with hematological diseases are more susceptible to nosocomial infection, which should be paid more attention to in clinical and laboratory practice. Rational antimicrobial therapy is an effective way for control of antimicrobial resistance. Key words: Blood culture; Pathogenic bacteria; Antibiotic; Antimicrobial susceptibility

Investigation of drug resistance and multilocus sequence typing for differentiation of strains of Candida tropicalis of Shanghai

Objective: To analyze the drug resistance of clinical isolates of Candida tropicalis in patients with infectious diseases, and preliminarily study their molecular characteristics. Methods: 95 strains of Candida tropicalis were isolated from the fungal culture specimens of 87 patients with infectious diseases in Shanghai Public Health Clinical Center from 2012 to 2015. Meanwhile, basic clinical data of patients were collected. The drug resistance of the strains to fungal drugs was analyzed by ATB FUNGUS 3 drug sensitivity test strips. All strains were classified by Multilocus sequence typing(MLST). Then, homology analysis was conducted by MEGA 5.2 software, and the evolutionary tree was mapped by using UPGMA method. Results: Patients distribution of strains was rendered as following: 31 strains from TB patients, 21 strains from HIV/AIDS patients, 19 strains from patients with liver disease, and 24 strains from rare cause infection or fever patients. The drug resistance rate to five antifungal drugs commonly used in clinical (amphotericin B, 5-fluorine cytosine, fluconazole, itraconazole, voriconazole) were 2.11% (2 strains), 0, 26.32% (25 strains), 26.32% (25 strains), and 26.32% (25 strains) respectively. Among the 25 azole-resistant strains: 14 strains were from rare cause infection or fever patients, 8 strains were from HIV/AIDS patients, and 3 strains were from tuberculosis patients. In MLST, 72 sequence types (ST types) were produced, 70 of which were new types. Evolutionary tree analysis showed that 95 strains of clinical strains distribute as three large clusters. 24 azole resistant strains (96.0%) were located in CLUSER Ⅰ. Conclusion: The isolated Candida tropicalis were mainly resistant to azole drugs. MLST typing indicates that they was closely related to their genetic background.

Gene polymorphism and drug sensitivity of Candida glabrata associated with vulvovaginal candidiasis in women of childbearing age

Objective To investigate genotypes and drug susceptibility of the 100 strains of Candida glabrata isolated from 100 women (including 50 pregnant women) in order to study the drug-resistance and gene polymorphism, and to investigate the correlation of drug-resistance, gestation and gene polymorphism. Methods Multilocus sequence typing (MLST) technique was introduced to identify sequences of 6 housekeeping genes from 100 isolates of Candida glabrata. The results were compared with sequence information in MLST databases by Clustalx software to determine a strain allelic profile and sequence type (ST). Drawing the phylogenetic tree by weighted paired group average method and the minimal spanning tree method of MEGA6.0 software, the microevolution and relationship between different strains were analyzed. ATB FUNGUS semi-automatic system was used to test the drug susceptibility. Fisher analysis method was used to analyze the correlation between the genotypes and pregnancy.Ridit analysis method was used to analyze the correlation between the genotypes and drug susceptibility. Results The 100 isolates belonged to 34 clone sequences. There were 53 isolates belonged to ST-7 ( 26 isolates of pregnancy), 7 isolates belonged to ST-3 (3 isolates of pregnancy), 6 isolates belonged to ST-19 (5 isolates of pregnancy ), 3 isolates belonged to ST-15 (1 isolate of pregnancy), 2 isolates belonged to ST-10 (2 isolates of pregnancy), 1 isolate belonged to the other types of ST. Total of 100 isolates of Candida glabrata were 100% sensitive to fluorocytosine and amphotericin. The effect of itraconazole was poor with the sensitive rate of 20%. The resistance rates of fluconazole and voriconazole were 4% and 1% respectively. All genotypes were sensitive to voriconazole except ST-X1. In the correlation between genotype and itraconazole resistance, ST-7 as the standard group, the Ridit values in the group of ST-15, ST-19 and other types of ST were not included the mean Ridit value of the standard group in itraconazole (0.5). The system evolution tree was built using the neighbor-joining method (NJ) . All genotypes could be divided into 3 groups, as Ⅰ, Ⅱ, Ⅲ. Group Ⅰ had 44 cases, group Ⅱ had 53 cases , group Ⅲ had 3 cases . All the collected clinical strains had small genetic distances during molecular evolution. Conclusions ST-7 was the dominant genotype in Guiyang. No correlation between different STs and patients′ pregnancy was found. The different drug susceptibility in itraconazole between ST-7, ST-15, ST-19 and other STs were found. The Candida glabrata associated with VVC showed highly discrimative diversity. However, the phylogenic analysis exhibited genetic similarity among the strains studied.(Chin J Lab Med, 2018, 41: 596-600) Key words: Vulvovaginal candidosis; Candida glabrata; Polymorphism, genetic; Microbial sensitivity tests

In vitro susceptibility of Candida spp. to fluconazole, itraconazole and voriconazole and the correlation between triazoles susceptibility: Results from a five-year study

Candida spp. is a common cause of invasive fungal disease. The aim of this study was to examine the susceptibility of Candida spp. to fluconazole, itraconazole and voriconazole and explore the correlation between triazoles susceptibility. The antifungal susceptibility in the present study was measured by ATB Fungus 3 method, and the potential relationship was examined by obtaining the correlation of measured minimal inhibitory concentrations (MICs) of Candida spp. isolates. A total of 2099 clinical isolates of Candida spp. from 1441 patients were analyzed. The organisms included 1435 isolates of Candida albicans, 207 isolates of Candida glabrata, 65 isolates of Candida parapsilosis, 31 isolates of Candida krusei, 268 isolates of Candida tropicalis. Voriconazole and itraconazole were more active than fluconazole and against Candida spp. in vitro. The fluconazole, itraconazole and voriconazole MIC90 (MIC for 90% of the isolates) for all Candida spp. isolates was 4mg/L, 1mg/L and 0.25mg/L, respectively. There was a moderate correlation between the fluconazole MICs for Candida spp. isolates and this for voriconazole (R2=0.475; P<0.01) and itraconazole (R2=0.431; P<0.01). Voriconazole MICs for the Candida spp. isolates also correlated with those for itraconazole (R2=0.401; P<0.01). These observations suggest that the in vitro susceptibility of Candida spp. to fluconazole, itraconazole and voriconazole exhibits a moderate correlation.

Clinical characteristics and drug resistance of 176 strains of candida isolated from children with blood infections

Objective To analyze the pathogen distribution and drug resistance of candida isolated from children with blood infections in our hospital, and to provide reference for clinical effective prevention and treatment. Methods The blood specimens of pediatric patients were collected between January 2009 and December 2015, and were cultured using BacT/ALERT 3D and BD9140 instruments.The candida were separated with Sobaurandps agar culture medium, and identified with chromogenic medium, API 20CAUX test strips or VITEK- 2 compact YST card.The minimal inhibitory concentration of 5 drugs were determined by ATB FUNGUS 3 system. Results In 176 cases, 92 strains(52.3%) were from neonatal ward, and 46 strains(26.1%) were from PICU.In newborn group, 85 strains were isolated from premature, which contained the low and very low birth weight infants(37 strains), pneumonia(20 strains), neonatal respiratory distress syndrome(9 strains). In PICU, the strains were commonly isolated from children with severe infection.Among 176 strains of candida, 71 strains(40.3%) were C. albicans, 62 strains(35.2%)were C. parapsilosis, 16 strains(9.1%) were C. glabrata, 9 strains(5.1%) were C. tropicalis, and 18 strains(10.2%) belonged to other candida. Conclusion Candida blood infections can happen at all age of chlidren.The most common strains detected from blood were C. albicans, followed by C. parapsilosis.Most of these strains are susceptible to antifungal drugs, such as fluconazole, except C. glabrata.The sensitive rates to commonly used antifungal drug are more than 93%.The selection of antifungal drugs should be based on the species of strains. Key words: Blood infection; Candida; Children

English

The aims of the study were to isolate and identify the Candida species from clinical cases of candidiasis and to determine their anti-fungal susceptibily. Clinical samples such as vaginal swab, nails scrapings and squama were submitted to the Mycology Unit of Institut Pasteur of C&ocirc;te d&rsquo;Ivoire, from 2011 to September, 2015. Samples were screened for the growth of Candida species, which were then identified by chromogenic medium CandiSelect&reg;4 and Auxacolor 2&reg; (Biorad). Antifungal susceptibility was performed by ATB Fungus 3&reg; of Biom&eacute;rieux with the drugs Amphotericin-B, Flucytosine, Fluconazole, Itraconazole and Voriconazole. A total of 924 yeasts were isolated and Candida albicans was the common species isolated (40.3%), followed by Candida glabrata (29.2%) and Candida tropicalis (17.2%). Most of the isolates were collected from vaginal swabs 781 (84.5%) followed by squama 49 (5.67%). The results of the antifungal susceptibility test against vaginal Candida species indicated that 96.8 and 96.3% of the vaginal yeast isolated were susceptible to amphotericin B and voriconazole, respectively. The susceptibility rate of the yeasts was 67.7% to flucytosine, 91.8% to fluconazole, and 86.6% to itraconazole. A high proportion of resistance to Itarconazole was observed with all of the isolates tested. The study indicated that the vaginal Candida species were less susceptible to the flucytosine than to any azole drugs. In contrast, the susceptibility to flucytosine against Candida species isolated from other clinical samples was relatively good. The present study revealed that C. albicans was the most commonly found yeast from various clinical specimens; and reported that the fives antifungal drugs tested are still active against the Candida species. &nbsp; Key words: Candida species, fluconazole, amphotericin B, itraconazole, flucytosine, voriconazole. &nbsp

Natural occurrence of Fusarium species and fumonisins in stored cassava chips

Cassava chips are transformed products obtained following the fermentation and drying of cassava fresh roots. Once produced, chips can be stored for more than 180 days in conditions conducive for the development of toxigenic moulds. In this study, the incidence of Fusarium spp. is assessed from a set of 72 home-stored samples of cassava chips collected from farmers, during a 2-month monitoring survey period. Results from this survey enabled the recovery of 298 isolates of Fusarium spp. The Fusarium taxa detected included: Fusarium chlamydosporum, Fusarium equiseti, Fusarium verticillioides, Fusarium oxysporum, Fusarium pallidoroseum and Fusarium solani. F. oxysporum was associated with the highest level of isolation frequency (25%), whereas F. solani isolated was scanty (5%). Their level of recovery was increasingly important as the moisture content of samples increased and/or the product was stored for longer periods. Specific associations were observed to exist between the most frequently isolated Fusarium spp. The level of fumonisins further assessed showed that only 5 samples hosted this mycotoxin at concentration levels ranging between 0.22 and 1.7 mg/kg. Among the parameters used to assess its incidence, only storage duration showed significant (P<0.05) relationships with fumonisins. The occurrence of fumonisins as natural contaminants of cassava-based products is reported here for the first time. This study shows that no known fumonisin producing-Fusarium species was related to toxin occurrence in the samples collected. It can be hypothesized that any species of Fusarium infesting the samples studied could have the potential capability of producing the toxin as a result of a possible horizontal transfer of functional fumonisin gene clusters from an ancestral gene. Consequently, the present study suggests both investigations on genes responsible for plausible fumonisin formation associated with the Fusarium spp. identified from the samples collected as well as the various factors allowing their expression. Key words: Fusarium, fumonisins, cassava chips, Cameroon, rural areas.

Typing and antifungal susceptibility of the candida species isolated in geriatric patients at a tertiary care center

Objective : In this study we aimed to detect, identification and distribution of the Candida species in blood and urine samples; and antifungal susceptibility of Candida bloodstream isolates in geriatric patients Methods: All Candida species isolated from blood and urine cultures samples of patients over than 65 years of during the period December 2011 -November 2014 in Izmir Tepecik Training and Research Hospital were enrolled in this study. For Candida species identification conventional methods, colony appearance in candida chromogenic agar and for some unidentified isolates API ID32C AUX (BioMerieux, France) was used. Antifungal susceptibility testing of the isolates was performed with API ATB Fungus 3 (BioMerieux, France). Results: During the study period 681 Candida species were isolated in blood and urine samples of patients over than 65 years. When the sample species were evaluated, Candida species detected in 561(82.4%) urine sample, and 120 (17.6%) blood samples. Most isolated species were respectively detected C. albicans (47.0%), C.parapsilosis (16.0%), C.tropicalis (15.9%), C.glabrata (12.2%), C.kefy ( 3.7%) and C.krusei (2.8%). C. albicans detected the most common in urine samples (51.7 %), on the other hand C.parapsilosis the most common species in blood samples (50.8%). In general surgery unit, C.tropicalis was found as the most common isolate. On the other hand C.albicans the most common species in the other units and services. C.parapsilosis rate in blood cultures increased with age. Antifungal susceptibility of the Candida bloodstream isolates were detected as 97.5% for flucytosine, 95.8% for amfotericin B, 82.5% for fluconazole, 91.7% for itraconazole and 77.5% for voriconazole. Conclusion: The most frequently isolated yeast species in blood and urinesamples of geriatric patients has been found C. albicans. C.parapsilosis especially frequently isolated from blood cultures and increasing the frequency with age. Voriconazole in Candida species is notable for low sensitivity rates. Key words: Candida species, candidemia, candiduria, blood culture, Antifungal susceptibility, geriatric

Distribution and Drug Susceptibility of Candida spp. Associated With Female Genital Tract Infection, Chongqing, China.

BackgroundVulvovaginal candidiasis is defined as vulvovaginitis associated with vaginal carriage of Candida spp. and is a common problem with a high rate of morbidity.ObjectivesTo investigate the distribution of Candida spp. and evaluate the corresponding antifungal susceptibility in women with genital tract infection in Chongqing, southwestern China.Patients and MethodsSamples (n = 2.129) were obtained from female patients with symptoms of genital tract infection. Candida spp. were isolated from the specimens and were identified using a coloration medium and the VITEK 2 Compact automatic microbial identification system. Antifungal susceptibility testing was performed using the ATB FUNGUS drug susceptibility testing system.ResultsFrom 2,129 samples, 478 (22.45%) isolates of Candida were isolated, of which 395 (82.64%) were Candida albicans, 39 (8.16%) were C. glabrata, 21 (4.39%) were C. tropicalis, 9 (1.88%) were C. parapsilosis, and 14 (2.93%) were other Candida spp. The resistance of C. albicans, C. glabrata, and C. tropicalis to 5 antifungal drugs (amphotericin B, voriconazole, fluconazole, 5-fluorocytosine, and itraconazole) ranged from 0.5% to 6.4%, 0% to 7.7%, and 0% to 9.6%, respectively.ConclusionsCandida albicans was the major pathogen associated with candidiasis of the female genital tract in patients in Chongqing. The results of the antifungal sensitivity of the isolates suggest that it is important for clinicians to administer appropriate antifungals for the treatment of Candida spp. infections.