Evaluation of Agar Candida ID2 (bioMerieux) a chromogenic medium for yeasts differentiation

Invasive diagnostic and therapeutic methods, widespread antibiotic therapy and rising percent of the immunocompromised patients cause incrementation of frequency of occurrence of the yeast infection. C. albicans is the most commonly isolated species of Candida from clinical samples. However, recently growth of frequency of isolation Candida non - albicans from clinical specimens have been observed. Yeast-like fungi different from C. albicans have become serious clinical problem. Conventional methods of identification of the yeast-like fungi carry away a lot time enough. Employment of chromogenic agar shortens latency on result. We decided to examine the usefulness ofAgar Candida ID2 (CAN2) (bioMérieux) in the identification of Candida species. The subjects within the study were 146 of Candida spp strains which were isolated from the clinical specimens of patients hospitalized at the University Hospital in Bydgoszcz. Germ tube test. Api 20C AUX test (bioMérieux) and Agar Candida ID2 (bioMérieux) were used. We have ascertained correspondence of identifying species amounted to 82.2% of analyzed Candida species between API 20C AUX test and kind of growth on CAN2 medium. Divergence of results received between CAN2 medium and API 20C AUX test suggests necessity of conducting of verification data with other methods. In conclusion, our study shows that Agar Candida ID2 is an effective medium for the isolation yeast-like fungi and in preliminary identification of Candida species direct from clinical materials.     

Yeast-like fungi as etiologic agents of blood infections in patients hospitalized in 1998-1999

The aim of the study was the analysis of frequency of yeast-like fungi as etiological agents of fungemias in patients hospitalized in operative and conservative wards of Medical Academy Central Clinical Hospital in Warsaw in 1998-1999. Peripheral blood samples and collected from vascular catheters were incubated in BacT/Alert system(Organon Teknika, USA). Positive blood samples were inoculated on Sabouraud medium with chloramphenicol (bioMerieux, France) (the time of cultivation from 48 h to 7 days at 30 C) and on chromogenic medium BBL CHROMagar Candida (Becton Dickinson, USA). Fungal strains were identified by standard mycological procedures using ID 32 C strips (ATB system, bioMerieux, France) and tests of Sanofi Diagnostics Pasteur (France). The total number of positive blood cultures was 1724. Fifty eight fungal strains were isolated from blood samples (3.36%). Strains belonged to 4 genera: Candida (55), Trichosporon (1), Saccharomyces (1) and Pichia (1). Thirty eight fungal strains were isolated from peripheral blood samples. Forty seven fungal strains were cultured from patients hospitalized in operative wards. Among fungi isolated from peripheral blood samples C. albicans (10), C. glabrata (9) and C. parapsilosis (5) strains dominated. From blood samples collected from vascular catheters most often C. albicans (7), C. glabrata (4) and C. parapsilosis (3) were isolated.     

Etiologic agents of fungemia in hospitalized patients]

The aim of performed examinations was the analysis of fungi as etiological agents of blood infections in patients hospitalized in surgical wards, internal medicine wards and intensive care units of the Medical Academy Central Clinical Hospital in Warsaw. Blood samples from patients hospitalized in 1997 were examined. Peripheral blood samples were incubated in BacT/Alert system (Organon Teknika, USA). Positive blood samples were inoculated on Sabouraud medium with chloramphenicol (bioMerieux, France or Oxoid, England). The time of cultivation was from 48 hours to 7 days at 30 degrees C. Fungal strains were identified by standard mycological procedures with the use of chromogenic medium BBL CHROMagar Candida (Becton Dickinson, USA) and biochemical test ID 32 C (bioMerieux, France). Susceptibility of strains to antifungal agents was determined by ATB FUNGUS method (bioMerieux, France). The total number of positive blood cultures in 1997 was 1380. Forty-two fungal strains were isolated from blood samples (3%). Strains belonged to the following species: C. albicans (17 isolates), C. parapsilosis (15), C. glabrata (3), melibiosica (2), C. pelliculosa (2), C. guilliermondii (1), C. tropicalis (1) and T. beigelii (1). Among fungi cultured from patients hospitalized in operative wards dominated C. parapsilosis (11) and C. albicans (10) strains, whereas from patients hospitalized in conservative wards most often C. albicans (6) strains were isolated. Candida strains were mostly susceptible to antifungal agents tested. It was interesting to culture Trichosporon beigelii (T. cutaneum) strain as an etiological agent of fungemia. This strain was multidrug-resistant.     

In vitro activity of amphotericin B and anidulafungin against Candida spp. biofilms

Invasive infections caused by Candida spp. are increasing worldwide and are becoming an important cause of morbidity and mortality in immunocompromised patients. A large number of manifestations of candidiasis are associated with the formation of biofilms on inert or biological surfaces. Candida spp. biofilms are recalcitrant to treatment with conventional antifungal therapies. The aim of this study was dual 1) to determine the prevalence of biofilm producers among clinical isolates from catheter (16 C. albicans ) and blood culture (2 C. albicans and 30 C. tropicalis), and 2) to determine the activity of amphotericin B and anidulafungin against C. albicans and C. tropicalis biofilms of 24 and 48 hours of maturation. Biofilms were developed using a 96-well microtitre plate model and production and activity of antifungal agents against biofilms were determined by the tetrazolium (XTT) reduction assay. Of catheter and blood isolates, 62.5 and 56.25%, respectively, produced biofilms. By species, 68.42% of C. albicans and 53.33% of C. tropicalis were biofilm producers. C. albicans biofilms showed more resistance to amphotericin B and anidulafungin than their planktonic counterparts. Complete killing of biofilms was never achieved, even at the highest concentrations of the drugs tested. Anidulafungin displayed more activity than amphotericin B against C. albicans biofilms of 24 hours of maturation (GM MIC 0.354 vs. 0.686 microg/ml), but against C. tropicalis biofilms amphotericin B was more active (GM MIC 11.285 vs. 0.476 microg/ml). In contrast, against biofilms with 48 hours maturation, amphotericin B was more active against both species.     

The presence of bacteria and yeast like fungi in specimens from surgical patients

The aim of this study was to determine the incidence of Candida spp. strains in specimens obtained from surgically treated patients as well as to analyze the accompanying bacterial flora, both aerobic and anaerobic. The material came from two groups of patients. In the first group consisting of patients operated for colon and rectum carcinoma, the samples included peritoneal fluid, colon or rectum bioptates, pus, blood, and wound swabs. In the other group, biopsy material and smears from post operation wounds were taken from patients who underwent a surgical treatment of larynx carcinoma. Altogether, 282 various clinical specimens from 165 patients were analysed, and 41 Candida spp. strains were isolated: 39 strains of C. albicans and 2 strains of C. tropicalis. In 20 out of 41 specimens infected with Candida spp. (48.8%) the co-infection with bacterial aerobic flora was found. In 10 cases (24.4%), the fungi were isolated together with aerobic and anaerobic bacterial flora, whereas in 2 specimens (4.9%) the anaerobes and Candida albicans were diagnosed. The remaining 9 samples showed only the presence of Candida spp. (21.9%). From among aerobic bacterial flora Enterococcus spp. strains (n = 17) and Gram negative rods from Enterobacteriaceae family (n = 13) were the most frequently isolated. The bacterial strains of Streptococcus spp. (n = 5), Pseudomonas spp. (n = 3), Staphylococcus spp. and Corynebacterium spp. (2 strains, both) were identified more rarely. Bacteroides spp. were the most frequent members of bacterial anaerobic flora (n = 10). Other isolated anaerobic bacteria were classified as Fusobacterium spp. or Peptostreptococcus spp. (1 strain each). E. coli and Enterococcus spp. strains of aerobic bacterial flora were more frequently isolated together with Candida spp. CONCLUSIONS: (i) Mixed bacterial flora was found to predominate in the clinical material from the patients after surgery. (ii) Candida spp. were most frequently found together with aerobic bacterial flora.     

Activity of anidulafungin against Candida biofilms

Currently, no standardized method to study the in vitro activity of antifungal agents on biofilms is available, thus, the comparison among different authors is difficult. The studies discussed in this review use the XTT reduction to measure the activity of antifungals on biofilms of 24 h of maturation. To date, biofilm anidulafungin MICs of 47 isolates of Candida spp. (25 Candida albicans, 16 Candida tropicalis, 5 Candida dubliniensis and 1 Candida parapsilosis) have been published. The geometric mean MIC of anidulafungin on biofilms of Candida spp. is of 1.18 microg/ml. Against isolates of species with great capacity of biofilm formation, the geometric mean MIC is 0.325 (C. albicans), 2 (C. parapsilosis) and 0.5 microg/ml (C. dubliniensis). No echinocandin has activity on C. tropicalis biofilms. In addition, anidulafungin can be used for lock therapy of catheters since it is the echinocandin with the least in vitro paradoxical effect.     

Analysis of microorganisms isolated from febrile neutropenic children with neoplastic disease

The microbiological evaluation of the blood was carried out as a continued monitoring of the microorganism culture using the colourmetric system VITAL 200 (bio-Mérieux). There have been analysed 4660 bacteriological research results of the peripheral blood, blood from Broviac and from Broviac liquid of the children suffering from cancer treated in the years 1997-2000 in the Pediatric, Hematology and Oncology Clinique of the State Clinical Hospital in Bydgoszcz. There have been gained 1032 positive cultures from KZZ, KZB, PZB. There have been recognized 259 bacteremia and 22 fungemia by the children with fever in the neutropenia period. In the analysed four years in the blood dominated Gram-positive bacteria. Among Gram-positive bacteria there were mostly Staphylococcus spp. (42.5%), mostly CNS, fewer numerous were Streptococcus spp. (14.5%) and Corynebacterium spp. (5.9%). Among Gram-negative bacteria mostly were isolated Acinetobacter spp. (25.6%), Pseudomonas spp. (9.7%), E. coli (13.8%), Enterobacter spp. (13.9%), Klebsiella spp. (9.2%). There were observed few infections by strains resistant to many antibiotics, S. maltophilia, B. cepacia, E. faecium, S. haemolyticus. All strains Staphylococcus spp. were sensitive to vancomycin. There have not been found Enterococcus spp. resistant to glycopeptides. Most active against Gram-positive rods were carbapenems and aminoglycosides.     

Nucleic acid sequence-based amplification (NASBA) detection of medically important Candida species.

Nucleic Acid Sequence Based Amplification (iNASBA), an isothermal amplification technique for nucleic acids, was evaluated for the identification of medically important Candida species using primers selected from 18S rRNA sequences conserved in fungi. An RNA fragment of 257 nucleotides was amplified for Candida albicans. Nineteen different fungi were tested for rRNA amplification with the NASBA. All were positive when analyzed on agarose gel, whereas human RNA was negative. For the identification of Candida species, NASBA amplification products were analyzed in an enzyme bead-based detection format, using species-specific biotinylated probes and a generic Candida HRPO probe or a membrane-based system using biotinylated probes and avidin-HPRO. Discrimination of the major human pathogenic Candida spp. was based on a panel of biotinylated probes for C. krusei, C. tropicalis, C. albicans, C. glabrata, and C. lusitaniae. Using rRNA dilutions obtained from pure cultures of C. albicans, the combination of NASBA and the enzymatic bead-based detection yielded a sensitivity equivalent to 0.01 CFU. In a model system using 1 ml of artificially contaminated blood as few as 1-10 CFU of C. albicans could be detected. Testing of 68 clinical blood samples from patients suspected of candidemia showed that eight samples were positive for C. albicans and one for C. glabrata. Testing of 13 clinical plasma samples from patients suspected of fungemia identified the presence of C. albicans in two specimens. The whole procedure of sample preparation, amplification and identification by hybridization can be performed in 1 day. This speed and the observed sensitivity of the assay make the NASBA a good alternative to PCR for the detection of candidemia.     

连续5年无菌体液标本中分离真菌的鉴定及药敏分析

目的回顾性调查2002-2006年华西医院住院患者无菌体液标本真菌培养的情况,分析真菌菌种及其耐药特点,为临床诊断、治疗提供参考。方法标本接种沙堡弱培养基进行分离培养,采用科马嘉念珠菌显色培养基（CHRO-Ma-gar）和API-20CAUX鉴定系统结合形态学进行菌种鉴定,使用念珠菌药敏试条（ATB-Fungus 2）对2006年来自血液标本中的真菌进行药敏试验。结果2002-2006年间检出的阳性样本数依次为7株、22株、39株、32株及57株;血液来源73株,清洁中段尿来源59株,是主要样本来源;分离真菌以白念珠菌和热带念珠菌为主,占70%以上;2006年血培养中共分离出16株念珠菌,体外药敏情况详见文中。结论临床无菌体液标本中真菌的检出率有逐年上升的趋势;菌株以白念珠菌和热带念珠菌为主,同时近平滑念珠菌、克柔念珠菌、光滑念珠菌、马尔尼菲青霉菌等菌株也有出现;样本来源以血液、清洁中段尿为主;体外药敏总体耐药率低,但是逐渐出现了对氟康唑耐药的白念珠菌和热带念珠菌,应引起高度重视。     

Evaluation of fungaemia infections in a Hungarian university hospital between 1996 and 2009

The incidence of Candida species causing bloodstream infections in the University Hospital of Szeged, Hungary, between 1996 and 2009, and the susceptibilities of these isolates to antifungal agents were evaluated.Automated blood culture systems (Vital, bioMérieux, Marcy-l'Etoile, France; and BACTEC 9120, Becton-Dickinson Diagnostic Systems, Sparks, USA) were used. The in vitro susceptibilities of the yeast isolates to antifungal agents were determined by the Etest method (AB Biodisk, Solna, Sweden).Bloodstream infections were caused by yeast strains in 231 cases during this period, and 226 Candida strains were cultured from 216 candidaemia patients. Bloodstream infections caused by multiple Candida spp. were diagnosed almost every year. Of the 216 patients, 67 were children; and 55 infants needed intensive care. In 2005, C. glabrata caused an increase in the incidence of invasive fungal infections in the Neonatal Intensive Care Unit. The PFGE analysis of 12 isolates distinguished 4 different karyotypes. The incidence of bloodstream infections caused by fungi did not change during the 14-year study period. The most frequent species cultured from blood samples were C. albicans and C. glabrata. The incidence of resistant isolates remained constant. The local trends of fungaemia must be monitored and compared with global reports.     

深部真菌感染临床特点分析

目的了解深部真菌感染患者的性别、年龄、感染部位、住院科室、菌种分布及真菌耐药情况,为临床防治真菌感染提供研究依据。方法收集荆州市中心医院2009年1月至2009年12月微生物实验室分离的真菌446株,采用科马嘉显色琼脂及API220C Aux鉴定系统鉴定,并使用ATMTMFUNGUS3真菌药敏卡进行体外药敏试验。结果临床真菌感染男性占72%,以老年患者为主,大于60岁者占54.9%;感染的真菌主要分布于呼吸内科和ICU,分别占35.5%、24.9%;主要感染部位为呼吸道,占91.3%;主要菌种为白假丝酵母菌、热带念株菌、近平滑假丝酵母菌、光滑念株菌和克柔念株菌,分别占64.2%、13.2%、9.6%、7.6%和5.4%;合并细菌感染的感染真菌100株,占22.2%,细菌中以革兰阴杆性菌为主,占96%;药敏试验结果显示真菌对各抗真菌药具有较好的敏感性。结论临床真菌感染已日益突出,以呼吸科及ICU患者老年男性为主,儿童真菌感染亦不容忽视,感染菌种以白假丝酵母菌和热带念株菌为主,临床应加强对这些真菌感染的预防和监测,防止真菌感染。     

New chromogenic agar medium for the identification of Candida spp

A new chromogenic agar medium (Candida diagnostic agar [CDA]) for differentiation of Candida spp. is described. This medium is based on Sabouraud dextrose agar (Oxoid CM41) and contains (per liter) 40.0 g of glucose, 10.0 g of mycological peptone, and 15.0 g of agar along with a novel chromogenic glucosaminidase substrate, ammonium 4-(2-[4-(2-acetamido-2-deoxy-beta-D-glucopyranosyloxy)-3-methoxyphenyl]-vinyl)-1-(propan-3-yl-oate)-quinolium bromide (0.32 g liter(-1)). The glucosaminidase substrate in CDA was hydrolyzed by Candida albicans and Candida dubliniensis, yielding white colonies with deep-red spots on a yellow transparent background after 24 to 48 h of incubation at 37 degrees C. Colonies of Candida tropicalis and Candida kefyr were uniformly pink, and colonies of other Candida spp., including Candida glabrata and Candida parapsilosis, were white. CDA was evaluated by using 115 test strains of Candida spp. and other clinically important yeasts and was compared with two commercially available chromogenic agars (Candida ID agar [bioMerieux] and CHROMagar Candida [CHROMagar Company Ltd.]). On all three agars, colonies of C. albicans were not distinguished from colonies of C. dubliniensis. However, for the group containing C. albicans plus C. dubliniensis, both the sensitivity and the specificity of detection when CDA was used were 100%, compared with values of 97.6 and 100%, respectively, with CHROMagar Candida and 100 and 96.8%, respectively, with Candida ID agar. In addition, for the group containing C. tropicalis plus C. kefyr, the sensitivity and specificity of detection when CDA was used were also 100%, compared with 72.7 and 98.1%, respectively, with CHROMagar Candida. Candida ID agar did not differentiate C. tropicalis and C. kefyr strains but did differentiate members of a broader group (C. tropicalis, C. kefyr, Candida lusitaniae plus Candida guilliermondii); the sensitivity and specificity of detection for members of this group were 94.7 and 93.8%, respectively. In addition to the increased sensitivity and/or specificity of Candida detection when CDA was used, differentiation of colony types on CDA (red spotted, pink, or no color) was unambiguous and did not require precise assessment of colony color.     

10年肠道真菌培养结果分析

目的探讨浙江大学医学院第一附属医院住院患者肠道真菌分离状况与趋势变化。方法回顾分析2000年1月1日至2009年12月30日10年间在该院送检的住院患者粪便标本的真菌分离率、真菌种类和年度变迁变化特点。结果 10年间从送检全部疑似肠道真菌感染的2 344份粪便标本中共检到真菌1 456株,归属5属19种,每年的检出率在55.7%67.0%。分离菌株中以白色念珠菌（74.0%）占首位,其次是光滑念珠菌（11.4%）,再次是热带念珠菌（7.1%）,光滑念珠菌和热带念珠菌分离率分别从2000年的4.9%、6.6%上升到2009年的16.8%、10.6%,呈上升趋势。结论该院10年间肠道真菌的分离率较高,白色念珠菌的分离率一直位于首位,非白色念珠菌的分离率处于上升趋势。     

Factors influencing adherence of Candida spp. to host tissues and plastic surfaces

Attachment of Candida spp. to host tissues and plastic surfaces is the first and a crucial step that initiates colonization by yeast cells and subsequent development of disseminated fungal infection. These infections are associated with high degree of morbidity, mortality and extra cost. Modern trends have focused not only on how best to treat but also on how to prevent Candida infections. To achieve this goal, the factors that influence the adherence of Candida spp. to biological and non biological surfaces have been studied. C. albicans adheres at a degree higher than that of the other Candida spp. and C. tropicalis adheres to a lesser extent. This may reflect the higher pathogenicity of C. albicans compared to the other Candida spp. Germinated C. albicans cells adhere to host tissue more readily than do yeast-phase. Sugars play an important role in the adherence of Candida spp. Overall, galactose was found to promote the adherence of Candida spp. to host tissues and plastic surfaces more than any other mono or disaccharide. Amino sugars on the other hand inhibit the adherence of the yeast cells. Divalent ions such as Ca2+ and Mg2+ promote the adherence of Candida spp. more than monovalent ions. Candida spp. express on their surface receptors, which interact with a wide variety of host proteins including fibrinogen, fibronectin, lamanin, and type I and IV collagen thus binding Candida spp. To glycoproteinaceous conditioning film at the blood-polymer interface. Coaggregation of Candida spp. with other bacteria promotes colonization of yeast cells to oral biofilm, host tissues, and to surfaces of the indwelling vascular catheters. These factors form the basis for the interference with the adherence of Candida spp.     

Otomycoses of candidal origin in eastern Slovakia

Mycological analysis of swabs and scraping samples from the external ear canals of 40 patients with clinically diagnosed otomycosis (10 neonates, 30 adults) revealed the presence of fungi as etiological agents. They were investigated microscopically using 20 % potassium hydroxide, and by cultivation on Sabouraud's glucose agar. The Candida species were identified using the germ-tube test, micromorphology observations of colonies on rice agar, and particularly by the commercial kit AUXAcolor. The following Candida species were identified in the aural material examined: C. albicans (n = 21; 52.5 %), C. parapsilosis (11; 27.5), C. tropicalis (3; 7.5), C. krusei (3; 7.5), C. guilliermondii (2; 5.0). The above yeasts were present in samples together with Staphylococcus epidermidis (31), S. aureus (16), alpha-hemolytic streptococci (14), Neisseria spp. (14), Proteus mirabilis (3), Pseudomonas aeruginosa (3), Escherichia coli (1) and Haemophilus influenzae (1). The most frequent predisposing factors for otomycosis were swimming in public pools and/or bath, spa and diabetes mellitus.     

Fungi inhabiting the healthy human gastrointestinal tract: a diverse and dynamic community

Fungal DNA was selectively amplified, and the ITS region sequenced, from fecal samples taken from 45 healthy human volunteers at one (21 volunteers) or two (24 volunteers) time points. Seventy-two operational taxonomic units, representing two phyla and ten classes of fungi, were recovered. Candida yeasts, notably Candida tropicalis (present in 51 samples), and yeasts in the Dipodascaceae (39 samples), dominated, while 38 OTUs were detected in a single sample each. Fungi included known human symbionts (Candida, Cryptococcus, Malassezia and Trichosporon spp.), common airborne fungi (Cladosporium sp.) and fungi known to be associated with food (Debaryomyces hansenii and high salt fermented foods; Penicillium roqueforti and blue cheese). In contrast with gut-associated bacteria, fungi occurred in much lower abundance and diversity, and fungal composition appeared unstable over time.     

Study of acute vulvovaginitis in sexually active adult women, with special reference to candidosis, in patients of the Francisco J. Muñiz Infectious Diseases Hospital

The results of microbiological vaginal secretions samples obtained from 749 women (from July 2001 to July 2002) were studied in the Bacteriology Unit of the Francisco Javier Mu?iz Hospital from Buenos Aires. All patients suffered acute vulvovaginitis were child bearing and sexually active women, 334 of them were HIV-positive. The following are the results of the microbiological studies: Lactobacillus spp 50.6%, Gardnerella vaginalis 25.6%, Candida spp 17.4%, Trichomonas vaginalis 5.3%, Neisseria gonorrhoeae 0.3% and B group Streptococcus 0.8%. Candida vaginitis was significantly more frequent in HIV-positive patients, (21.6% vs 14%; p = 0.0086); meanwhile, trichomoniasis was less common although the difference was not statistically significant (3.6 vs 6.7%, p = 0.0810). The following Candida species were isolated in this study: Candida albicans 76.8%, Candida glabrata 15.6%, Candida parapsilosis 2.9%, Candida tropicalis 1.5% and Candida krusei 0.7%. Eight cases (6.2%) of vaginitis were produced by two Candida species (C. albicans and C. glabrata), and in three cases (2.17%) Saccharomyces cerevisiae were isolated. Five women suffering acute vaginitis with Candida spp presented another etiologic agent of vaginal infection, three cases T. vaginalis and two cases G. vaginalis. The following are some of the most important findings of this study: 1) Half of the patients presented a normal microbial biota; 2) Candida spp vaginitis was significantly more frequent among HIV-positive women; 3) we observed a high incidence of Candida glabrata infections (15.9%), 4) 6.2% of vaginal candidiasis were caused by more than one Candida species and, 5) the susceptibility pattern of C. albicans and C. glabrata isolates against fluconazole was similar to the one observed in other studies. The majority of C. albicans isolates were susceptible to fluconazole (MIC90 = 0.5 microg/ml) meanwhile C. glabrata strains were much less susceptible to this drug (MIC50 and MIC90 = 32 microg/ml).     

In-vitro activity of 5-fluorocytosine against 1,021 Spanish clinical isolates of Candida and other medically important yeasts

The aim of this study was to determine the prevalence of primary resistance to 5-fluorocytosine (5FC) among clinical isolates of yeasts in Spain where this drug is not currently available for therapy. We have tested the in vitro activity of 5FC against 1,021 recent yeast clinical isolates, including 522 Candida albicans, 140 Candida parapsilosis, 68 Candida glabrata, 41 Candida dubliniensis, 50 Candida guilliermondii, 34 Candida tropicalis, 28 Candida krusei, 20 Candida famata, 11 Cryptococcus neoformans, 5 Cryptococcus albidus, 43 Rhodotorula spp., 24 Trichosporon spp., 5 Saccharomyces cerevisiae, 9 Pichia spp., and 21 isolates from other 11 yeast species. The MICs were determined by the ATB Fungus agar microdilution test (bioMerieux, France) and the following interpretive breakpoints were used: susceptible, > 4 microg/ml; intermediate, 8 to 16 microg/ml; resistant, > 32 microg/ml. 5FC was very active against Candida spp. and other medically important yeasts as 852 (83.4%) of the studied isolates were susceptible (MIC < 4 microg/ml). The species most susceptible to 5FC were C. dubliniensis (100%of isolates; MIC90, 0.25 microg/ml), C. famata (100% of isolates; MIC90, 0.25 microg/ml), C. guilliermondii (98%of isolates; MIC90, 0.25 microg/ml), C. glabrata (95.5% of isolates; MIC90, 0.25 microg/ml), and C. neoformans (90.9% of isolates; MIC90, 2 microg/ml). Primary resistance to 5FC was very uncommon, and a MIC > 32 microg/ml, indicator of in vitro resistance, was observed in 106 isolates (10.4%): 77 C. albicans (16.5% of isolates; MIC90, > 128 microg/ml), 9 C. parapsilosis (6.4% of isolates; MIC90, 8 microg/ml), 4 C. albidus (80% of isolates, MIC50, > 128 microg/ml), 3 C. glabrata (4.4% of isolates; MIC90, 0.25 microg/ml), 3 C. tropicalis (8.8% of isolates; MIC90, 4 microg/ml), 2 C. krusei (7.1% of isolates; MIC90, 8 microg/ml), 2 Rhodotorula spp. (4.6% of isolates, MIC90, 1 microg/ml), 8 Trichosporon spp. (33.3% of isolates; MIC90, 64 microg/ml), and 1 C. lipolytica (50% of isolates). Interestingly, most C. albicans (67 out of 77 isolates) resistant to 5FC were serotype B isolates.     

眼部真菌感染菌种分布特征

目的分析眼部真菌感染的致病情况和菌种分布特征。方法统计山东省眼科研究所2000～2005年间所有真菌感染病例的培养结果,按照感染部位分类并分析不同菌种的致病情况。结果6年间共有970份真菌培养资料,阳性结果691份,阳性率为71.2%(691/970)。其中角膜溃疡阳性率为86.2%(669/776),镰刀菌占73.2%(490/669);眼内炎阳性率为10.4%(19/182),曲霉菌占68.4%(13/19);泪囊炎阳性率为25.0%(3/12),念珠菌占100.0%(3/3)。结论不同的感染部位常见的真菌菌种不同,镰刀菌是真菌性角膜溃疡的主要致病菌,曲霉菌是真菌性眼内炎的主要致病菌,而念珠菌则是泪囊炎的主要致病菌。     

Amphotericin B-metronidazole combination against Candida spp

Oropharyngeal candidiasis (OPC) remains a common opportunistic infection in HIV-infected patients. Candida albicans is the most frequent causative agent of OPC. However, non-albicans spp. are being increasingly isolated. Candidal cell wall proteins and mannoproteins play important roles in the biology and patogenesis of candidiasis. In the present study, we have analyzed the proteinaceous components associated with cell wall extracts from C. albicans, Candida tropicalis, Candida pseudotropicalis, Candida krusei, Candida glabrata, Candida parapsilosis, Candida guilliermondii and Candida rugosa obtained from HIV-infected patients with recurrent OPC. Cell wall proteinaceous components were extracted with beta-mercaptoethanol and analyzed using electrophoresis, immunoblotting (with antisera generated against C. albicans cell wall components, and with serum samples and oral saline rinses from patients with OPC), and lectin-blotting (concanavalin A) techniques. Numerous molecular species were solubilized from the various isolates. Major qualitative and quantitative differences in the polypeptidic and antigenic profiles associated with the cell wall extracts from the different Candida spp. were discernible. Some of the antibody preparations generated against C. albicans cell wall components were able to recognize homologous materials present in the extracts from non-albicans spp. Information on cell wall antigens of Candida species may be important in the therapy and prevention of HIV-related OPC.