Candida species cause vulvovaginitis and resistance to antifungals used for treatment

In this study were identified Candida species from vaginal secretion isolates, evaluated their in vitro antifungal susceptibilities, and correlated these features with antifungal agents prescribed for patients assisted in a primary care service. Species identification by Polymerase Chain Reaction showed that 36.5% of isolates were characterized as non-C. albicans species. In antifungal susceptibility tests most isolates were susceptible to ketoconazole, fluconazole, and itraconazole, although between 40% and 50% of isolates show resistance or dose-dependent susceptibility to miconazole and nystatin, respectively. Analysis of drugs prescribed to patients revealed that 34.2% of the isolates were considered resistant to agents used in treatment. Several Candida species can cause vulvovaginitis and exhibit different susceptibility profiles to antifungal drugs used in treatment. The identification of Candida species is relevant and useful to the epidemiological management of infections. The antifungal susceptibility test may also be useful for choosing most effective drug treatment for each patient.

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Conventional therapy and new antifungal drugs against Malassezia infections

Medical Mycology ◽

10.1093/mmy/myaa087 ◽

2020 ◽

Author(s):

Wafa Rhimi ◽

Bart Theelen ◽

Teun Boekhout ◽

Chioma Inyang Aneke ◽

Domenico Otranto ◽

...

Keyword(s):

Antifungal Susceptibility ◽

Clinical Signs ◽

Bloodstream Infections ◽

Antifungal Drugs ◽

Malassezia Spp ◽

Susceptibility Tests ◽

In Vitro Antifungal Susceptibility ◽

Susceptibility Profiles

ABSTRACT Malassezia yeasts are commensal microorganisms occurring on the skin of humans and animals causing dermatological disorders or systemic infections in severely immunocompromised hosts. Despite attempts to control such yeast infections with topical and systemic antifungals, recurrence of clinical signs of skin infections as well as treatment failure in preventing or treating Malassezia furfur fungemia have been reported most likely due to wrong management of these infections (e.g., due to early termination of treatment) or due to the occurrence of resistant phenomena. Standardized methods for in vitro antifungal susceptibility tests of these yeasts are still lacking, thus resulting in variable susceptibility profiles to azoles among Malassezia spp. and a lack of clinical breakpoints. The inherent limitations to the current pharmacological treatments for Malassezia infections both in humans and animals, stimulated the interest of the scientific community to discover new, effective antifungal drugs or substances to treat these infections. In this review, data about the in vivo and in vitro antifungal activity of the most commonly employed drugs (i.e., azoles, polyenes, allylamines, and echinocandins) against Malassezia yeasts, with a focus on human bloodstream infections, are summarized and their clinical implications are discussed. In addition, the usefulness of alternative compounds is discussed.

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Molecular Identification and Antifungal Susceptibility Patterns of Candida Species Isolated from Candidemia Patients in Yasuj, Southwestern Iran

Jundishapur Journal of Microbiology ◽

10.5812/jjm.117643 ◽

2021 ◽

Vol 14 (7) ◽

Author(s):

Shaghayegh Rostami Yasuj ◽

Maral Gharaghani ◽

Seyed Sajjad Khoramrooz ◽

Marjan Salahi ◽

Ali Keshtkari ◽

...

Keyword(s):

Mortality Rate ◽

Amphotericin B ◽

Molecular Identification ◽

Candida Species ◽

Antifungal Susceptibility ◽

Hospitalized Patients ◽

Susceptibility Tests ◽

In Vitro Antifungal Susceptibility ◽

Susceptibility Patterns

Background: Candidemia is the most common systemic infection in hospitalized patients causing high mortality. Hence, the diagnosis of this infection in the early stage with appropriate antifungal therapy is paramount. Objectives: The study aimed at molecular identification of Candida species isolated from candidemia patients and evaluation of the in vitro antifungal susceptibility patterns of these strains to fluconazole, amphotericin B, and caspofungin. Methods: In the present study, 800 hospitalized patients who were suspected to have candidemia were sampled. Candida species were isolated and identified based on morphological characteristics and PCR-sequencing of the ITS1-5.8S-ITS2 region. Antifungal susceptibility tests for fluconazole, amphotericin B, and caspofungin were performed according to the Clinical and Laboratory Standards Institute protocol M27-A3. Also, clinical data were recorded from the patients' records. Results: Twenty-seven patients among the sample of hospitalized patients were found to have candidemia. A total of 33.3% of candidemia patients were treated with amphotericin B, in which case the mortality rate was 14.8%. The majority of patients (59%) were from the neonatal intensive care unit, and premature birth was the most common underlying condition. Candida albicans (n = 18; 66.6%) was the most common species isolated from blood cultures, followed by C. parapsilosis (n = 7; 25.9%), C. pelliculosa (n = 1; 3.7%), and C. tropicalis (n = 1; 3.7%). Only one C. albicans isolate resistant to fluconazole (minimum inhibitory concentration = 32 µg/mL). Conclusions: Generally, C. albicans has been the most frequent causative agent of candidemia. Resistance to antifungal drugs among candidemia agents was rare. Also, the identification of Candida isolates at the species level with in vitro antifungal susceptibility tests helps manage candidemia patients better and decrease the mortality rate among them.

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Antifungal Susceptibility In Vitro Determined by the Etest(r) for Candida Obtained from the Oral Cavity of Irradiated and Elderly Individuals

Brazilian Dental Journal ◽

10.1590/0103-6440201300115 ◽

2015 ◽

Vol 26 (2) ◽

pp. 99-104 ◽

Cited By ~ 3

Author(s):

Edimilson Martins de Freitas ◽

Larissa Cavalcanti Monteiro ◽

Michelle Bonfim da Silva Fernandes ◽

Hercílio Martelli Junior ◽

Paulo Rogério Ferreti Bonan ◽

...

Keyword(s):

Amphotericin B ◽

Candida Species ◽

Antifungal Susceptibility ◽

Culture Collection ◽

Morphological Criteria ◽

Group 2 ◽

In Vitro Antifungal Susceptibility ◽

Mic Minimum Inhibitory Concentration ◽

Dose Dependent

This study aimed to evaluate the in vitro antifungal susceptibility of Candida species of head-and-neck-irradiated patients (Group 1), non-institutionalized (Group 2) and institutionalized elders (Group 3) using Etest(r) methodology. Candida was isolated from saliva and presumptively identified by CHROMagar Candida(r), confirmed by morphological criteria, carbohydrate assimilation (API 20C AUX(r)) and genetic typing (OPE 18). The collection was made from 29, 34 and 29 individuals (Groups 1, 2 and 3, respectively) with 67 isolates. Etest(r) strips (ketoconazole, itraconazole, fluconazole, amphotericin B and flucytosine) on RPMI (Roswell Park Memorial Institute) agar, on duplicate, were used to evaluate susceptibility. ATTC (American Type Culture Collection) 10231 (Candida albicans) was used as quality control. Among the 67 isolates of Candida species, most were susceptible to azoles, flucytosine and amphotericin B. None of the isolates showed resistance and dose-dependent susceptibility to amphotericin B. There were nine strains resistant to itraconazole, six to fluconazole and two to ketoconazole and ten dose-dependent, mainly to flucytocine. The highest MIC (minimum inhibitory concentration) to C. albicans, C. tropicalis, C. parapsilosis was 2.671 μg.mL-1, 8.104 μg.mL-1, 4.429 μg.mL-1, all for flucytosine. C. krusei and C. glabrata were associated with higher MIC for azoles and C. glabrata with higher MIC to flucytosine. In summary, susceptibility to all tested antifungal agents was evident. The isolates were more resistant to itraconazole and dose-dependent to flucytosine. A comparison of C. albicans in the three groups showed no outliers. Higher MIC was associated with C. krusei and C. glabrata.

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Molecular Identification, And Antifungal Susceptibility Patterns of Candida Species Isolated From Candidemia Patients in Yasuj, Southwestern Iran

10.21203/rs.3.rs-438157/v1 ◽

2021 ◽

Author(s):

Shaghayegh Rostami Yasuj ◽

Seyed Sajad Khoramrooz ◽

Marjan Salahi ◽

Ali Keshtkari ◽

Jabar Taghavi ◽

...

Keyword(s):

Mortality Rate ◽

Amphotericin B ◽

Molecular Identification ◽

Antifungal Susceptibility ◽

Hospitalized Patients ◽

Antifungal Drugs ◽

Its2 Region ◽

Susceptibility Tests ◽

Susceptibility Patterns

Abstract Candidemia is the most common systemic infection in hospitalized patients and causing high mortality. Hence, the diagnosis of this infection in the early-stage with appropriate antifungal therapy has been attributed to the lowest mortality. The aims of this study are molecular identification of Candida species isolated from candidemia patients and evaluated the in vitro antifungal susceptibility patterns of these strains to fluconazole, amphotericin B, and caspofungin. In the present study, 800 hospitalized patients who suspected candidemia were sampled. Candida species were isolated and identified based on morphological and PCR-sequencing of the ITS1-5.8S-ITS2 region. Antifungal susceptibility tests for fluconazole, amphotericin B, and caspofungin was performed according to the Clinical and Laboratory Standards Institute M27-A3. Also, clinical data were recorded from patient's records. Overall, 27 candidemia patients were detected among hospitalized patients. 33.3% of candidemia patients were treated with amphotericin B, however, the mortality rate was 14.8%. The majority of patients (59%) were from the neonatal intensive care unit and premature born was the most underlying condition. C. albicans (n = 18; 66.6%) was the most common species isolated from blood cultures, followed by C.parapsilosis (n = 7; 25.9%), C.pelliculosa ( n = 1;3.7% ) and C.tropicalis (n = 1;3.7%). Only one C. albicans isolate were resistance to fluconazole (MIC = 32 µg/mL). Generally, C. albicans has been the most frequent causative agent of candidemia. Resistance to antifungal drugs among candidemia agents was rare. Also, the identification of Candida isolates at the species level with in-vitro antifungal susceptibility tests can manage and decrease the mortality rate among candidemia patients.

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In Vitro Antifungal Susceptibility Profiles of 12 Antifungal Drugs against 55 Trichophyton schoenleinii Isolates from Tinea Capitis Favosa Patients in Iran, Turkey, and China

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01753-16 ◽

2016 ◽

Vol 61 (2) ◽

Cited By ~ 6

Author(s):

Shuwen Deng ◽

Saham Ansari ◽

Macit Ilkit ◽

Haleh Rafati ◽

Mohammad T. Hedayati ◽

...

Keyword(s):

Antifungal Agents ◽

Antifungal Susceptibility ◽

Antifungal Drugs ◽

Content Type ◽

Microdilution Method ◽

Broth Microdilution Method ◽

In Vitro Antifungal Susceptibility ◽

Trichophyton Schoenleinii ◽

Susceptibility Profiles

ABSTRACT Trichophyton schoenleinii is an anthropophilic dermatophyte mainly causing tinea favosa of the scalp in certain regions of the world, especially Africa and Asia. We investigated the in vitro susceptibilities of 55 T. schoenleinii isolates collected over the last 30 years from Iran, Turkey, and China to 12 antifungals using the CLSI broth microdilution method. Our results revealed that terbinafine and ketoconazole were the most potent antifungal agents among those tested, independently of the geographic regions where strains were isolated.

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Antifungal susceptibility of bloodstream yeasts isolated at a public children’s hospital in Brazil: comparison of the Etest® and the AFST–EUCAST microdilution method

Canadian Journal of Microbiology ◽

10.1139/w07-095 ◽

2007 ◽

Vol 53 (12) ◽

pp. 1300-1306 ◽

Cited By ~ 7

Author(s):

Flávia E. Matsumoto ◽

Amanda L.T. Dias ◽

Márcia S.C. Melhem ◽

Maria W. Szeszs ◽

Marcos E. Auler ◽

...

Keyword(s):

Amphotericin B ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Candida Spp ◽

In Vitro Susceptibility ◽

Microdilution Method ◽

Susceptibility Tests ◽

Susceptibility Profiles

This study compared the minimum inhibitory concentration (MIC) results from the proposed standard methods of the Antifungal Susceptibility Testing Subcommittee of the European Committee on Antibiotic Susceptibility Testing (AFST–EUCAST) with the commercial system Etest® in the evaluation of susceptibility to flucytosine, fluconazole, itraconazole, voriconazole, and amphotericin B of 136 Candida spp. isolated from the blood of hospitalized children. The results presented a greater agreement among Etest® MICs ±2 log2 dilutions of AFST–EUCAST for fluconazole (98.1% and 96.3%) and voriconazole (100% and 100%) for Candida albicans and Candida parapsilosis . For Candida glabrata , the agreement was greater only for fluconazole (81.8%) and voriconazole (100%). For amphotericin B, the agreement between the methods was low for all species. The agreement percentage among the Etest® and AFST–EUCAST susceptibility profiles was high according to the MIC breakpoints recommended by the M27-A2 protocol for the majority of the yeasts, except for fluconazole and itraconazole against Candida tropicalis and for itraconazole against C. glabrata and Candida krusei . According to both methodologies, a great number of Candida spp. isolates showed an in vitro susceptibility to all evaluated antifungal agents. Overall, both procedures can be reliable techniques for susceptibility tests of yeasts, but the assessment of interlaboratory agreement and correlation of MICs by different methods with in vivo response are of great importance.

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Epidemiological and Microbiological Study of Onychomycosis

JOURNAL FOR CLINICAL AND DIAGNOSTIC RESEARCH ◽

10.7860/jcdr/2021/48332.14640 ◽

2021 ◽

Author(s):

Sunita Kabi ◽

Bichitrananda Swain ◽

Swati Jain

Keyword(s):

Candida Species ◽

Susceptibility Testing ◽

Antifungal Susceptibility ◽

Nail Plate ◽

Laboratory Diagnosis ◽

Antifungal Susceptibility Testing ◽

Antifungal Drugs ◽

Diffusion Method ◽

Resistance Pattern

Introduction: Onychomycosis is a common fungal infection of nail. It may be caused by dermatophytes, non-dermatophytic moulds or yeasts involving nail bed, nail plate or matrix of nail. As the fungi show variable susceptibility to antifungal drugs and treatment requires long duration of antifungal therapy, so it’s prevalence as well as proper laboratory diagnosis and antifungal susceptibility testing is essential for effective therapy. Aim: To find the prevalence of onychomycosis with demography along with various aetiology and the suitable antifungal drugs used for treatment. Materials and Methods: For this prospective study, over a period of two years a total of 300 nail samples were processed in the Department of Microbiology at IMS and SUM Hospital, Bhubaneswar, Odisha, India. The wet mount for microscopic examination was prepared using 20% Potassium Hydroxide (KOH) and examined after overnight incubation. Culture was done in duplicate in Sabouraud’s Dextrose Agar (SDA) tubes; one with actidione and another without it and both were incubated at 25°C in Biological Oxygen Demand (BOD) incubator. Culture tubes growing yeasts were further subjected to speciation by germ tube test, culture on Chromogenic (CHROM) agar and on cornmeal agar. In-vitro antifungal susceptibility testing was performed against Candida species using disc diffusion method on Muller Hinton agar. Chi-square test was used for statistical analysis of the results. Results: Onychomycosis can affect a wide age group though seen commonly at 31-40 years equally in both male and females. Fingernail infection was observed mostly in female cases. It was caused by Candida species (66%), moulds (24%) and dermatophytes (10%) and out of Candida sp. C.albicans was the main culprit. Although all the Candida strains were susceptible to amphotericin B, still some of them showed resistance to the commonly used antifungals like fluconazole and itraconazole. Conclusion:Candida albicans was the most common aetiological agent which contributed for onychomycosis and showed a variable resistance pattern to the commonly used antifungals. Proper laboratory diagnosis and selection of antifungal drug is essential prior to institution of therapy for successful treatment of this disease.

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In vitro Antifungal Susceptibility Profiles of Cryptococcus neoformans var. grubii and Cryptococcus gattii Clinical Isolates in Guangxi, Southern China

Frontiers in Microbiology ◽

10.3389/fmicb.2021.708280 ◽

2021 ◽

Vol 12 ◽

Author(s):

Najwa Al-Odaini ◽

Xiu-ying Li ◽

Bing-kun Li ◽

Xing-chun Chen ◽

Chun-yang Huang ◽

...

Keyword(s):

Cryptococcus Neoformans ◽

Amphotericin B ◽

Southern China ◽

Antifungal Susceptibility ◽

Sensu Stricto ◽

Cryptococcus Gattii ◽

Antifungal Drugs ◽

In Vitro Antifungal Susceptibility ◽

Susceptibility Profiles

This study analyzed the in vitro drug sensitivity of Cryptococcus spp. from Guangxi, Southern China. One hundred three strains of Cryptococcus were recovered from 86 patients; 14 were HIV positive and 72 were HIV negative. Ninety-two strains were identified as Cryptococcus neoformans var. grubii, while 11 strains were identified as Cryptococcus gattii (5 C. gattii sensu stricto and 6 Cryptococcus deuterogattii). The recovered strains were tested against commonly used antifungal drugs (fluconazole, amphotericin B, 5-fluorocytosine, itraconazole, and voriconazole) and to novel antifungal drugs (posaconazole and isavuconazole) using CLSI M27-A4 method. The results showed that all isolates were susceptible to most antifungal drugs, of which the minimum inhibitory concentration (MIC) ranges were as follows: 0.05–4 μg/ml for fluconazole, 0.25–1 μg/ml for amphotericin B; 0.0625–2 μg/ml for 5-fluorocytosine, 0.0625–0.25 μg/ml for itraconazole, 0.0078–0.25 μg/ml for voriconazole, 0.0313–0.5 μg/ml for posaconazole, 0.0020–0.125 μg/ml for isavuconazole for C. neoformans var. grubii isolates, and 1–16 μg/ml for fluconazole, 0.125–1 μg/ml for 5-fluorocytosine, 0.25–1 μg/ml for amphotericin B, 0.0625–0.25 μg/ml for itraconazole, 0.0156–0.125 μg/ml for voriconazole, 0.0156–0.25 μg/ml for posaconazole, and 0.0078–0.125 μg/ml for isavuconazole for C. gattii isolates. Furthermore, some C. neoformans var. grubii isolates were found to be susceptible-dose dependent to 5-fluorocytosine and itraconazole. In addition, a reduction in the potency of fluconazole against C. gattii is possible. We observed no statistical differences in susceptibility of C. neoformans var. grubii and C. gattii in the tested strains. Continuous observation of antifungal susceptibility of Cryptococcus isolates is recommended to monitor the emergence of resistant strains.

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New Antifungal Susceptibility Test Based on Chitin Detection by Image Cytometry

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01101-19 ◽

2019 ◽

Vol 64 (1) ◽

Author(s):

Yan Wang ◽

Arisandy N. Andriampamonjy ◽

Sebastien Bailly ◽

Cécile Garnaud ◽

Danièle Maubon ◽

...

Keyword(s):

Antifungal Susceptibility ◽

Image Cytometry ◽

Culture Conditions ◽

Fungal Species ◽

Antifungal Drugs ◽

Calcofluor White ◽

Content Type ◽

Antifungal Susceptibility Test ◽

Susceptibility Tests

ABSTRACT The antifungal susceptibility tests used in clinical laboratories have several limitations. We developed a new test, SensiFONG, based on the detection of chitin levels after exposure to antifungal drugs. The optimal culture conditions were 30°C for 6 h for yeast strains and 26°C for 16 h for molds. The strains were exposed to a range of echinocandin or azole concentrations. Chitin was stained with calcofluor white. The percentage of fungal cells with high chitin levels was determined with an automatic epifluorescence microscope. The SensiFONG results were compared to those with the EUCAST method. Image acquisition and analysis were performed with ScanR software. Fifty-nine strains (28 Candida albicans, 17 Candida glabrata, and 14 Aspergillus fumigatus) were analyzed. Thresholds for the classification of strains as resistant or susceptible were determined for each fungal species. The strains displaying an increase in chitin content of ≥32% for C. albicans, ≥6% for C. glabrata, and ≥17% for A. fumigatus were considered susceptible. The application of these thresholds to all 59 strains resulted in a sensitivity of 0.87, 0.93, and 1.00 and a specificity of 0.93, 0.84, and 0.82 for C. albicans, C. glabrata, and A. fumigatus, respectively. The correlation between the results obtained in the SensiFONG and EUCAST assays was excellent. We developed a new test, SensiFONG, based on a new concept. While current assays assess growth inhibition, our test detects changes in chitin levels after exposure to antifungal drugs. Here, we present preliminary results and we propose a proof of concept of this methodology.

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In vitro antifungal susceptibilities of six antifungal drugs against clinical Candida glabrata isolates according to EUCAST

Current Medical Mycology ◽

10.18502/cmm.6.2.2692 ◽

2020 ◽

Author(s):

Mahnaz Fatahinia ◽

Ali Zarei Mahmoudabadi ◽

Marzieh Halvaeizadeh ◽

Elham AboualiGalehdari ◽

Neda Kiasat

Keyword(s):

Candida Glabrata ◽

Antifungal Susceptibility ◽

Antifungal Drugs ◽

Health Centers ◽

Regional Patterns ◽

Alternative Drug ◽

Life Threatening ◽

Immunocompromised Hosts ◽

Dose Dependent

Background and Purpose: Candida glabrata is the second cause of candidiasis. The mortality rate of C. glabrata infections is about 40%; accordingly, it may be life threatening, especially in immunocompromised hosts. Regarding this, the current study was conducted to evaluate the regional patterns of the antifungal susceptibility of clinical C. glabrata isolated from the patients referring to the health centers located in Ahvaz, Iran. Materials and Methods: In this study, a total of 30 clinical strains of C. glabrata isolates were recovered from different body sites (i.e., vagina, mouth, and urine). Phenotypic characteristics and molecular methods were used to identify the isolates. The minimum inhibitory concentration (MIC) was determined according to the European Committee on Antimicrobial Susceptibility Testing. Results: Our findings demonstrated that 20%, 80%, and 6.7% of the isolates were resistant to amphotericin B, terbinafine, and posaconazole, respectively, while all the isolates were found to be fluconazole susceptible dose dependent and susceptible to voriconazole and caspofungin. Conclusion: Our study suggested that voriconazole had high potency against C. glabrata isolates. Consequently, this antifungal agent can be an alternative drug in the treatment of resistant patients. These results can be helpful for the successful treatment of patients in different regions.

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