Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CANDIDA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,351 records · Page 75Linked to original sources

The epidemiology of non-albicans Candida in oropharyngeal candidiasis in HIV patients.

Oropharyngeal candidiasis (OPC) is the most common fungal infection in patients with HIV infection. Fluconazole has been proven to be very effective in treating this infection, but decreased susceptibility of Candida to this drug has emerged. Certain non-albicans species such as C. glabrata and C. krusei are commonly less susceptible to fluconazole than C. albicans and are being isolated with increased frequency in HIV patients. The purpose of this study was to determine if the presence of non-albicans Candida with OPC in HIV patients had an impact on clinical presentation. This study shows that late-stage HIV patients have a high prevalence of Candida with decreased susceptibility to fluconazole, especially non-albicans species. OPC episodes with non-albicans isolates were more likely to require higher doses of fluconazole to achieve clinical cure. Also, the presence of non-albicans Candida was more frequently associated with severe symptoms.

AIDS-Related Opportunistic Infections↗

Relationship between growth inhibition and mitochondrial function in petite-negative yeasts. I. Effects of antibiotics and dyes upon pathogenic and non-pathogenic Candida species.

Antibiotics and dyes which preclude growth of Saccharomyces cerevisiae in media containing oxidizable carbon sources arrested the growth of Candida albicans, Candida tropicalis and Candida utilis even in glucose medium. The growth in the presence of sub-inhibitory concentrations of the various antibiotics and dyes determined a reduction in the cell survival but with no accumulation of respiratory deficient mutants. Under these culture conditions, the total respiration declined leaving a residual antimycin A-resistant--hydroxamate-sensitive O2 uptake, and the amount of the respiratory cytochromes aa3 and b synthesized was reduced. SDS gel electrophoresis of soluble proteins prepared from the antibiotic-treated cells showed some bands in the MW range 92-100 K, which became faint after the cells were grown in the presence of some mitochondrial inhibitors. The ultrastructural analysis of these cells evidenced disappearance of the mitochondrial cristae and their replacement by unfolded membranes. The data obtained suggest that the petite negative trait of Candida could depend on the non-viability or on the very low viability of those cells which have lost their mitochondrial function.

Anti-Bacterial Agents↗

Candida glabrata: review of epidemiology, pathogenesis, and clinical disease with comparison to C. albicans.

Until recently, Candida glabrata was considered a relatively nonpathogenic commensal fungal organism of human mucosal tissues. However, with the increased use of immunosuppressive agents, mucosal and systemic infections caused by C. glabrata have increased significantly, especially in the human immunodeficiency virus-infected population. A major obstacle in C. glabrata infections is their innate resistance to azole antimycotic therapy, which is very effective in treating infections caused by other Candida species. Candida glabrata, formerly known as Torulopsis glabrata, contrasts with other Candida species in its nondimorphic blastoconidial morphology and haploid genome. C. glabrata currently ranks second or third as the causative agent of superficial (oral, esophageal, vaginal, or urinary) or systemic candidal infections, which are often nosocomial. Currently, however, there are few recognized virulence factors of C. glabrata and little is known about the host defense mechanisms that protect against infection. Two established animal models (systemic and vaginal) have been established to study treatment, pathogenesis, and immunity. Treatment of C. glabrata infections can include azoles but often requires amphotericin B or flucytosine. This review summarizes all known clinical and experimental information about C. glabrata infections with comparisons to C. albicans as a means of contrasting the two species commonly observed and emphasizing the many recognized differences.

Animals↗

Adherence of Candida albicans to a fibrin-platelet matrix formed in vitro.

The adherence of Candida albicans to a fibrin-platelet matrix formed in vitro was studied. Platelet-rich plasma obtained from rabbits was incubated with thrombin and CaCl2 to form a clot in tissue culture dishes. Such clots were then infected with 3 x 10(7) C. albicans cells per 0.3 ml prelabeled with [U14C]-glucose, and the percent adherence was measured after 30 min of incubation by counting the radioactivity in saline washes of the clot as well as a streptokinase-streptodornase digest of the corresponding clot. Heat- and formaldehyde-killed cells did not adhere as well as viable cells. Pretreatment of C. albicans with trypsin, chymotrypsin, and pronase reduced adherence to the clots. Normal rabbit serum and anti-Candida antiserum also inhibited adherence 40 and 100%, respectively, Diethylaminoethyl-purified anti-Candida gamma globulin (1:8) completely inhibited adherence, whereas purified normal serum gamma globulin did not. Several Candida spp. and Saccharomyces cerevisiae showed differences in their ability to adhere to clots. C. albicans and C. stellatoidea presented the highest adherence, whereas C. krusei, C. guilliermondii, and S. cerevisiae adhered less readily. Other species were intermediate in their ability to adhere.

Blood Platelets↗

Correlation between microdilution, E-test, and disk diffusion methods for antifungal susceptibility testing of posaconazole against Candida spp.

Agar-based antifungal susceptibility testing is an attractive alternative to the microdilution method. We examined the correlation between the microdilution, E-test, and disk diffusion methods for posaconazole against Candida spp. A total of 270 bloodstream isolates of Candida spp. with a broad range of posaconazole MICs were tested using the CLSI M27-A2 method for microdilution, as well as the M-44A method and E-test methods for agar-based testing on Mueller-Hinton agar supplemented with 2% glucose and 0.5 microg of methylene blue. MICs and inhibitory zone diameters at the prominent growth reduction endpoint were recorded at 24 and 48 h. The Candida isolates included Candida albicans (n = 124), C. parapsilosis (n = 44), C. tropicalis (n = 41), C. glabrata (n = 36), C. krusei (n = 20), C. lusitaniae (n = 3), and C. dubliniensis (n = 2). The overall concordance (i.e., the percentage of isolates within two dilutions) between the E-test and microdilution was 64.8% at 24 h and 82.6% at 48 h. When we considered an arbitrary breakpoint of < or = 1 microg/ml, the agreement between the E-test and microdilution methods was 87.8% at 24 h and 93.0% at 48 h. The correlation of MICs with disk diffusion zone diameters was better for the E-test than the microdilution method. Zone correlation for diameters produced by the disks of two manufacturers was high, with a Pearson test value of 0.941 at 24 h. The E-test and microdilution MICs show good concordance and interpretative agreement. The disk diffusion zone diameters are highly reproducible and correlate well with both the E-test and the microdilution method, making agar-based methods a viable alternative to microdilution for posaconazole susceptibility testing.

Antifungal Agents↗

DNA fingerprinting of Candida rugosa via repetitive sequence-based PCR.

A repetitive sequence-based PCR (rep-PCR) technique was developed to characterize the genotypic relatedness among Candida rugosa isolates. Two repetitive sequences, viz., Care-2 and Com29 from Candida albicans, were used to design primers Ca-21, Ca-22, and Com-21, respectively. When used alone or in combination, these primers generated discriminatory fingerprints by amplifying the adjacent variable regions of the genome. Twenty-three isolates from burn patients, eight from other human sources, and four C. rugosa isolates pathogenic in animals were placed into nine fingerprinting groups. Different primers placed these isolates into identical groups, indicating that rep-PCR is a specific and reproducible technique for molecular characterization of C. rugosa. Moreover, these primers unequivocally discriminated among other important Candida species such as C. albicans, C. glabrata, C. tropicalis, C. krusei, C. parapsilosis, C. kefyr, and C. lusitaniae. These data confirm the conservation of repetitive sequences in Candida species. Because of its ease and sensitivity, rep-PCR offers a relatively rapid and discriminatory method for molecular typing of C. rugosa in outbreaks.

Animals↗

Detection and identification of Candida species in experimentally infected tissue and human blood by rRNA-specific fluorescent in situ hybridization.

Two 18S rRNA-targeted oligonucleotide probes specific for Candida albicans and Candida parapsilosis were used to detect and identify by fluorescent in situ hybridization these medically important Candida species in deep organs of mice after experimental systemic infection. The C. albicans-specific probe detected fungal cells in kidney, spleen, and brain sections of a mouse infected with C. albicans but not in a mouse infected with the closely related species C. parapsilosis. Conversely, the C. parapsilosis-specific probe detected fungal cells in the deep organs of a mouse infected with C. parapsilosis but not in the deep organs of a C. albicans-infected mouse. In addition, the C. albicans-specific probe was used to detect this species in human blood spiked with yeast cells by a lysis-filtration assay and subsequent fluorescent in situ hybridization. By this assay, as few as three yeast cells per 0.5 ml of blood were consistently detected. Our results demonstrate that fluorescent in situ hybridization with species-specific rRNA-targeted oligonucleotide probes provides a novel, culture-independent method for the sensitive detection and identification of Candida species in clinically relevant material.

Animals↗

Comparison of the API Candida system with the AUXACOLOR system for identification of common yeast pathogens.

Two commercial systems for the identification of yeasts were evaluated by using 159 clinical isolates that had also been identified by conventional biochemical and morphological methods. The API Candida system correctly identified 146 isolates (91.8%), and the AUXACOLOR system correctly identified 145 isolates (91.2%). However, of the 146 isolates identified by the API Candida system, 23 required supplemental biochemical tests or morphological assessment to obtain the correct identification. The AUXACOLOR system gave no identification in 13 cases (8.2%), while the API Candida system gave an unreadable profile in only one case. Incorrect identifications were more common with the API Candida system (12 isolates; 7.5%) than with the AUXACOLOR system (1 isolate; 0.6%).

Automation↗

Trends in antifungal susceptibility among Candida sp. Urinary isolates from 1994 and 1998.

Antifungal susceptibilities were determined from 80 urinary isolates of Candida species collected in 1994 and 1998. Our findings demonstrate increasing geometric means of fluconazole MICs and fluconazole resistance in Candida albicans and Candida tropicalis (those for Candida glabrata were unchanged) within the 4-year span. Amphotericin B and voriconazole MICs remained constant.

Antifungal Agents↗

Distinguishing Candida species by beta-N-acetylhexosaminidase activity.

A variety of fungi produce the hydrolytic enzyme beta-N-acetylhexosaminidase (HexNAcase), which can be readily detected in assays by using p-nitrophenyl-N-acetyl-beta-D-glucosaminide as a substrate. In the present study we developed a microtiter plate-based HexNAcase assay for distinguishing Candida albicans and Candida dubliniensis strains from other yeast species. HexNAcase activity was detected in 89 of 92 (97%) C. albicans strains and 4 of 4 C. dubliniensis strains but not in 28 strains of eight other Candida species, 4 Saccharomyces cerevisiae strains, or 2 Cryptococcus neoformans strains. The HexNAcase activity in C. albicans and C. dubliniensis was strain specific. All except three clinical C. albicans isolates among the C. albicans strains tested produced enzyme activity within 24 h. These strains did produce enzyme activity, however, after a prolonged incubation period. For two of these atypical strains, genomic DNA at the C. albicans HEX1 gene locus, which encodes HexNAcase, showed nucleotide differences from the sequence of control strains. Among the other Candida species tested, only C. dubliniensis had a DNA sequence that hybridized with the HEX1 probe under low-stringency conditions. The microtiter plate-based assay used in the present study for the detection of HexNAcase activity is a simple, relatively inexpensive method useful for the presumptive identification of C. albicans and C. dubliniensis.

Acetylglucosamine↗

Distribution of pathogenic yeasts and humoral antibodies to candida among hospital inpatients.

The frequencies of the carriage of yeast pathogens and of serum precipitins to a variety of candida antigens among 254 patients generally tended to increase with the length of the patient's stay in hospital. This trend was observed even though none of the patients investigated showed signs or symptoms of superficial or systemic candidosis. The extent of the general trend varied considerably between subgroups of patients within the general categories of 'surgical' and 'nonsurgical' inpatients. Increases in both frequencies and quantities of yeasts in the mouth were most evident postoperatively among patients who underwent open-heart surgery and among nonsurgical patients who received antibiotics or steroids in hospital. The frequency of precipitins to Candida albicans cytoplasmic antigens in the absence of candidosis rose overall from 11% of 217 sera obtained within 24 hours of admission to 35% of 85 sera obtained five to 11 days after admission or operation. These 'false positive' antibodies were thought to arise after transient yeast overgrowth in the gut at the time of an acute illness or immediately after surgery. The study adds further data to documented examples of 'false positive' candida antibodies and indicates the need for care in the diagnostic interpretation of candida precipitin test results among groups of patients at risk of yeast overgrowth during their hospital stay.

Antibodies, Fungal↗

Detection and identification of the Candida species by 25S ribosomal DNA analysis in the urine of candidal cystitis.

Candida species in clinical urine samples were identified directly by the newly developed method of PCR analysis on 25S ribosomal DNA (rDNA). Two dogs were referred to the Animal Medical Center, Nihon University School of Veterinary Medicine, Fujisawa, Kanagawa, Japan for the examination of chronic cystitis. Microscopic examination of urine samples from these dogs revealed yeast cells. Urine culture on Sabouraud's dextrose agar at 27 degrees C for 5 days produced white to cream colored colonies. The isolates were identifical to Candida albicans and C. parapsilosis by mycological examination, respectively. The nucleotide sequences of 25S ribosomal DNA from these urine isolates showed 99% similarity to those of a reference strain of Candida albicans or C. parapsilosis. The nucleotide sequences of 25S rDNA obtained directly from urine samples were also identical to C. albicans and C. parapsilosis, respectively. Confirming the results on the isolates cultured from the same urine samples. This PCR analysis method could be available for the direct identification of Candida species in urine samples within 2 days.

Animals↗

Treatment of vaginal Candida infections.

Candida vaginitis is most commonly caused by Candida albicans (> 85%) with little evidence of an increase in vaginitis due to non-C. albicans species. Epidemiological studies are no longer possible in the US in the era of self-diagnosis and -treatment by women empowered by the availability of over-the-counter antimycotics. A new classification of vulvovaginal candidiasis into uncomplicated and complicated vaginitis has simplified choice and duration of antifungal therapy. Vaginitis due to C. albicans responds well to available therapy. In contrast, vaginitis due to Candida glabrata is associated with a high treatment failure rate. Candida vaginitis infection rates in HIV-positive women remain undetermined and reports of refractory fungal vaginitis have not been substantiated. In spite of the wide array of antifungal agents currently available, considerable limitations in available therapy exist in the effective management of complicated vaginitis.

Adult↗

Candida species and crop mycosis in broiler chickens.

A mycological survey of the crops of approximately 100 healthy birds from each of 6 grow-out operations revealed that the incidence of Candida in the crops ranged from 17.4 to 51.5% with a mean value of 32.3%. The population of Candida in the crops of birds found positive was of low magnitude in the majority of the chickens examined. Of the 573 birds examined in this study less than 1% exhibited visible lesions attributable to Candida. C. albicans comprised 95% of the isolates while C. ravautii, C. salmonicola, C. gulliermondi, C. papapsilosis, C. catenulata and C. brumptii comprised the remainder. The incidence and number of Candida in the crop was related apparently to management practices on the farm. The crops from four field outbreaks of crop mycosis were also studied. Three of the four cases of crop mycosis were characterized by multiple strains of C. albicans in the crop. In one case, C. parapsilosis also was isolated from the crop.

Animals↗

Candida spp. urinary tract infections in 13 dogs and seven cats: predisposing factors, treatment, and outcome.

Records from 20 animals (13 dogs, seven cats) with Candida spp. urinary tract infections were reviewed. Six Candida spp. were isolated; Candida albicans was the most common isolate. Concurrent diseases or nonantifungal drugs administered within 1 month of isolation included antibiotics (n=16), corticosteroids (n=6), diabetes mellitus (n=4), nonurogenital neoplasia (n=3), and noncandidal urogenital disease (n=14). All animals had sources of local or systemic immune compromise that likely predisposed to infection. Of five animals with resolution of infection, three did not receive specific antifungal treatment. The authors conclude that correction of predisposing conditions is likely critical for management of Candida spp. urinary tract infection.

Animals↗

[Comparative study of adherence of five Candida species to polyvinyl chloride].

Colonization of biomaterial by Candida species could be the first step of Candida infection. We examined the in vitro adherence capabilities of five Candida species to polyvinyl chlorure (PVC). Twenty stains were tested: C. albicans (9), C. glabrata (3), C. tropicalis (3), C. kefyr (4) and C. parapsilosis (1). The adherence to PVC was evaluated by direct microscopic examination. The results indicate that the adherence of C. albicans to PVC is similar to that of C. glabrata and C. tropicalis. Only C. kefyr adheres to a lower degree. We conclude that the adherence capabilities of non-albicans species were similar to that of C. albicans. There is a relationship between the adherence of Candida species and their abilities to colonize the biomaterial. The species, which are more adherent, are those, which are more virulent.

Biocompatible Materials↗

Candida-related changes and ASCUS: a potential trap!

Detection of potential pitfalls for the ASCUS interpretation is essential for appropriate patient management. Between 1991-1994, 50 cervicovaginal specimens with Candida spp. were submitted for pathologists' review because of a possible ASCUS diagnosis. None had been preceded by abnormal smears, and all were followed by one or more benign smears and/or biopsy. Candida-associated changes included nuclear enlargement with focal hyperchromasia and cytoplasmic changes of orangeophilia, vacuoles, and perinuclear rings. Initially, 16 cases had been interpreted as ASCUS and 34 as benign. Upon review, utilizing strict Bethesda System criteria for ASCUS and awareness of Candida-associated changes, 10 of the 16 ASCUS cases were reclassified as benign. Knowledge of Candida-associated changes which may mimic ASCUS can prevent overuse of the ASCUS term, providing optimal, cost-effective management.

Candida↗

Evaluation of the CaMAL2 promoter for regulated expression of genes in Candida albicans.

An expression vector (CIp10-MAL2p) for use in Candida albicans has been constructed in which a gene of interest can be placed under the control of the CaMAL2 maltase promoter and stably integrated at the CaRP10 locus. Using this vector to express the Candida URA3 gene from the CaMAL2 promoter, we have demonstrated tight regulation of CaURA3 expression by carbon source. Thus under conditions when the CaMAL2 promoter is not induced, expression of Candida URA3 was unable either to complement a C. albicans ura3 mutation or to confer sensitivity to 5-fluoroorotic acid, a compound which is highly toxic to URA3 strains. Since Candida albicans is an obligate diploid organism, analysis of gene function requires manipulation of both copies of any gene of interest. Our expression vector provides a strategy by which the remaining copy of a gene of interest can be placed under CaMAL2 promoter control in a strain where the first copy has been deleted, permitting analysis of gene function by manipulation of carbon source. CIp10-MAL2p should therefore provide a useful means for functional analysis of genes in C. albicans. We have used this strategy with C. albicans DPB2 to demonstrate that the gene is essential and that loss of function leads cells to adopt a hypha-like morphology as they cease proliferation.

Antigens, Fungal↗