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.

Antifungal susceptibility of clinically significant candida species by disk diffusion method

Antifungal susceptibility of candida. To perform antifungal susceptibility testing on candida isolates by disk diffusion method & study its susceptibility pattern. The present study was conducted in the department of Microbiology in a tertiary care hospital in Hyderabad from January 2013 to June 2014, with prior approval of the Institutional Ethics Committee. The present study was designed to perform antifungal susceptibility test on Candida isolates by Disk Diffusion Method and study its susceptibility pattern. 102 Candida isolates were subjected to Antifungal susceptibility testing by Disk diffusion method using Mueller-Hinton Agar + 2% Glucose and 0.5 μg/mL Methylene Blue Dye (GMB) Mediumas per CLSI guidelines. : Antifungal susceptibility test shows that C. albicans is more susceptible to all the antifungal agents tested. Resistance to azole group of drugs was more pronounced in non-albicans candida spp. Voriconazole seemed to be superior to Fluconazole with a better susceptibility in the Fluconazole resistant strains also.Findings of the antifungal susceptibility test suggest that Candida spp., differ in their susceptibility to antifungal agents. Antifungal susceptibility testing of Candida isolates will be helpful in guiding physicians to select the appropriate antifungal drug so that therapeutic failures can be avoided thus decreasing patient morbidity and mortality.

The Scent of Antifungal Propolis

Propolis contains many effective antifungal compounds that have not yet been identified and evaluated. In addition, distinguishing samples of propolis with high antifungal activity from less active ones would be beneficial for effective therapy. Propolis samples were collected from four different geographical regions in Hungary and used to prepare ethanol extracts for analysis. First, an antifungal susceptibility test was performed on Candida albicans. Then, gas chromatography-mass spectrometry (GC-MS) and an opto-electronic nose were applied for the classification of propolis samples. In three propolis samples, the IC50 was measured between 72 and 134 µg/mL, but it was not calculable in the fourth sample. GC-MS analysis of the four propolis samples identified several compounds belonging to the various chemical classes. In the antifungal samples, the relative concentration of 11,14-eicosadienoic acid was the highest. Based on the opto-electronic electronic nose measurements, 98.4% of the original grouped antifungal/non-antifungal cases were classified correctly. We identified several molecules from propolis with potential antifungal properties. In addition, this is the first report to demonstrate the usefulness of a portable opto-electronic nose to identify propolis samples with high antifungal activity. These results may contribute to the rapid and efficient selection of new fungicide-candidate molecules and effective propolis samples for treatment.

Antifungal Activity of 1,4-Dialkoxynaphthalen-2-Acyl Imidazolium Salts by Inducing Apoptosis of Pathogenic Candida spp.

Even though Candida spp. are staying commonly on human skin, it is also an opportunistic pathogenic fungus that can cause candidiasis. The emergence of resistant Candida strains and the toxicity of antifungal agents have encouraged the development of new classes of potent antifungal agents. Novel naphthalen-2-acyl imidazolium salts (NAIMSs), especially 1,4-dialkoxy-NAIMS from 1,4-dihydroxynaphthalene, were prepared and evaluated for antifungal activity. Those derivatives showed prominent anti-Candida activity with a minimum inhibitory concentration (MIC) of 3.125 to 6.26 μg/mL in 24 h based on microdilution antifungal susceptibility test. Among the tested compounds, NAIMS 7c showed strongest antifungal activity with 3.125 μg/mL MIC value compared with miconazole which showed 12.5 μg/mL MIC value against Candida spp., and more importantly >100 μg/mL MIC value against C. auris. The production of reactive oxygen species (ROS) was increased and JC-1 staining showed the loss of mitochondrial membrane potential in C. albicans by treatment with NAIMS 7c. The increased release of ultraviolet (UV) absorbing materials suggested that NAIMS 7c could cause cell busting. The expression of apoptosis-related genes was induced in C. albicans by NAIMS 7c treatment. Taken together, the synthetic NAIMSs are of high interest as novel antifungal agents given further in vivo examination.

New Antifungal Susceptibility Test Based on Chitin Detection by Image Cytometry

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.

Talaromyces atroroseus in HIV and non-HIV patient: A first report from Indonesia

We performed morphology, molecular study and antifungal susceptibility test on 10 Talaromyces sp. isolates: eight clinical isolates (human immunodeficiency virus (HIV) and non-HIV-patient) and two isolates from rats. All strains produced red soluble pigment and microscopically showed Penicillium-like structure in room temperature and yeast-like structure in 37°C. Based on molecular analysis, nine isolates were identified as Talaromyces atroroseus (including the isolates from rats) and one as T. marneffei. Our susceptibility result of T. marneffei supports the use of amphotericin B, itraconazole for talaromycosis marneffei management. Talaromyces atroroseus showed variable MIC to echinocandin, azole derivatives, 5-flucytosine and amphotericin B.

Quantitative Phytochemical Analysis and Antifungal Susceptibility of Vernonia amygdalina against Some Strains of Candida albicans

This study was aimed at determining the quantitative phytochemical analysis and antifungal susceptibility of Vernonia amygdalina against some strains of Candida albicans. Reflux method of extraction was used for the successive extraction of the leaves of Vernonia amygdalina. Quantitative phytochemical screenings were done to determine the amounts of phytochemicals that are present in the crude extracts, the study revealed that phytochemicals which include flavonoids, tannins, alkaloids, saponins and phenol were present in the crude extracts. Three different strains (P37005, RM1000 and SC5314) were subjected for antifungal susceptibility test, the antifungal susceptibility test of the crude extracts against the strains were determined at different concentrations of 40,60, 80 and 100 mg/ml using agar well diffusion method. The highest zone of inhibition (ZOI) was 21.00 ±0.30 mm which was recorded for methanol leaf extract (MLE) at a concentration of 100 mg/ml against SC5314 (isolate:B3). The MIC and MFC values for the most active crude extracts were 12.5 mg/ml and 100 mg/ml for the n-hexane crude extract against strain P37005 (isolate B1), the value of 12.5 mg/ml and 100 mg/ml was also revealed for the n-hexane crude extract against SC5314 (isolateB3) however, the methanol crude extract showed a value of 12.5mg/ml and 50mg/ml respectively against SC5314 (isolate:B3). The results from this study suggest that n-hexane and methanol crude extract have a better antifungal activity than the ethylacetate crude extract. This study also validate the claim of the local herbal practitioners of the use of the leaves of Vernonia amygdalina in curing candidiasis.

Anidulafungin Susceptibility Testing of Candida glabrata Isolates from Blood Cultures by the MALDI Biotyper Antibiotic (Antifungal) Susceptibility Test Rapid Assay

ABSTRACT Echinocandins are the recommended first-line antifungals for treatment of invasive candidiasis. The increasing number of Candida glabrata strains resistant against echinocandins is an emerging health care concern. The rapid detection of resistant C. glabrata isolates is an urgent requirement for clinical laboratories. In this study, we developed the MALDI Biotyper antibiotic (antifungal) susceptibility test rapid assay (MBT ASTRA) for the rapid detection of anidulafungin-resistant C. glabrata isolates directly from positive blood cultures. Of 100 C. glabrata strains, MBT ASTRA classified 69 as susceptible and 29 as resistant. Microdilution assays performed according to the Clinical and Laboratory Standards Institute (CLSI) guidelines, used as a standard reference, identified 65 susceptible, 9 intermediate, and 26 resistant isolates. Sequencing of hot spot 1 and hot spot 2 regions of the FKS1 and FKS2 genes classified 86 susceptible and 14 resistant isolates. The MBT ASTRA had sensitivity and specificity of 80% and 95%, respectively, compared to the microdilution method. Positive and negative agreement of MBT ASTRA was calculated at 100% and 80%, respectively, compared with the molecular sequencing approach. Together, these results revealed a high accuracy of MBT ASTRA compared to microdilution according to the CLSI and PCR analysis, resulting in a categorical agreement of 90% and 83%, respectively. The validity of MBT ASTRA was 98%. Importantly, MBT ASTRA provided antifungal susceptibility testing (AFST) within 6 h that was both accurate and reliable compared to the other two approaches, which require at least 24 h or are costly. Therefore, this method has the potential to facilitate clinical AFST rapidly at low sample costs for clinical labs already equipped with matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS).

Luliconazole, a New Antifungal, vs Amphotericin B, Voriconazole, Posaconazole and Caspofungin against Clinical and EnvironmentalAspergillusNigri Complex

ABSTRACTBlack Aspergilli are,the most causes of aspergillosis andAspergillus niger and A. tubingensis are two more frequently isolates. Although, amphotericin B was a gold standard for the treatment of invasive fungal infection for several decades, it replaced by several new antifungals. Furthermore, a novel antifungal, luliconazole, appears to offer the potential for improved therapy for aspergillosis. The aim of the present study was to compare the effect of a novel antifungal agent, luliconazole, with classical antifungalagainst clinical and environmental strains of black Aspergilli. Sixty seven strains of black Aspergilli were identified using morphological and molecular tests (β-Tubulin gene). Antifungal susceptibility test was applied according to CLSI M38 A2. The results were reported as MIC range, MIC50, MIC90and MICGM. In the present study,A. nigerwas the common isolate followed by,A. tubingensisand 54.1% (clinical) and 30% (environmental) of isolates were resistant to caspofungin. The highest resistant rate was found in amphotericin B for both clinical (86.5%) and environmental (96.7%) strains. Clinical strains ofAspergilluswere more sensitive to voriconazole (86.7%) than environmental strains (70.3%). On the other hand, 83.8% of clinical and 70% of environmental isolates were resistant to posaconazole, respectively. It is found that the lowest MIC range, MIC50, MIC90, and MICGMwas attributed to luliconazole in clinical strains. In conclusion, luliconazole vs. routine antifungal is a potent antifungal forA. nigercomplexin vitro. The MIC range, MIC50, MIC90and MICGMof luliconazole against black Aspergilli were the lowest among the representative tested antifungals.