scholarly journals Antifungal susceptibility profiles of otomycosis etiological agents in Ahvaz, Iran

Author(s):  
Maral Gharaghani ◽  
Marzieh Halvaeezadeh ◽  
Gholam Ali Jalaee ◽  
Simin Taghipour ◽  
Neda Kiasat ◽  
...  

Background and Purpose: Otomycosis is a secondary ear fungal infection among predisposed individuals in humid conditions. Aspergillus species are the most common etiologic agents of this infection. Several ototopical antifungals are currently used for the treatment of this disease; however, recurrence and treatment failure are usually observed in some cases. Regarding this, the present study was conducted to investigate the antifungal activity of caspofungin, azoles, and terbinafine against the isolated agents of otomycosis. Materials and Methods: This study was conducted on the specimens collected from 90 patients with otomycosis. The samples were cultured on Sabouraud dextrose agar and identified based on morphological characteristics, physiological tests, and microscopic features. Furthermore, the microdilution method was used for antifungal susceptibility testing according to the Clinical and Laboratory Standards Institute (CLSI) guidelines. Finally, the minimum inhibitory concentration (MIC) and minimum effective concentration (MEC) ranges, MIC/MEC50, MIC/MEC90, and geometric mean (GM) MIC/MEC were calculated for the isolates. Results: According to the results, 77 patients with otomycosis were positive for different Aspergillus (88.3%) and Candida (11.7%) species. Aspergillus niger complex (n=36) was found to be the most common agent, followed by A. flavus, A. terreus, and A. nidulans complexes. Furthermore, epidemiological cutoff values (ECVs) were lower than those presented by the CLSI for itraconazole and caspofungin in 98.5% and 42.6% of Aspergillus species, respectively. Terbinafine exhibited a great activity against Aspergillus species, while fluconazole revealed a low activity against both Aspergillus species. Based on the results, 77.8% of Candida species were resistant to caspofungin; however, miconazole and econazole had low MIC ranges. Conclusion: Aspergillus niger and A. flavus complexes were identified as the most common agents accounting for 85.7% of the isolates. In addition, terbinafine was identified as the best antifungal for both Aspergillus and Candida species. Moreover, tested azoles had relatively low MICs, whereas most of the isolates had the MIC values beyond the caspofungin ECVs.

2020 ◽  
Vol 18 (1) ◽  
pp. 28-36
Author(s):  
Apurva Kaushal ◽  
Pratik Gahalaut ◽  
R K Goyal ◽  
Neni Agarwal ◽  
Nitin Mishra ◽  
...  

Introduction: Non-dermatophytic molds (NDM) are filamentous fungi or yeast, commonly found in nature as saprophytes and plant pathogens. The incidence of onychomycosis due to NDM is 1.45 – 16.6%. NDMs are usually resistant to conventional antifungal treatment. Objective: To know the anti-fungal susceptibility pattern of non-dermatophyte fungi causing onychomycosis.  Materials and Methods: A prospective hospital based cross-sectional study was done on non - dermatophytic isolates from patients with clinical suspicion of onychomycosis. All non – dermatophytic isolates were subjected to anti-fungal susceptibility against terbinafine, itraconazole, fluconazole and griseofulvin by micro broth dilution method.  Results: NDM were isolated in 20.2% cases of clinically suspected onychomycosis, among which Fusarium species was the most common followed by Aspergillus species and Candida species. MIC50 (Mean Inhibitory Concentration) for overall non - dermatophytic isolates for terbinafine, itraconazole, fluconazole and griseofulvin was 0.25μg/mL, 0.5μg/mL, 32μg/mL and 2μg/mL respectively and the order of sensitivity was Itraconazole (74.7%) > terbinafine (68%) > Fluconazole (60%) > Griseofulvin (51.6%) of the study samples. For Fusarium species, the  sensitivity for terbinafine was (73.5%) > itraconazole (67.6%) > fluconazole (64.7%) and griseofulvin (64.7%). For Aspergillus species, the sensitivity for itraconazole was 79.1% > fluconazole (58.3%) > terbinafine (54.1%) > griseofulvin (50%). For Candida species, the sensitivity was fluconazole (83.3%) > itraconazole (75%) > terbinafine (41.6%), while no candida species was found sensitive to griseofulvin.  Conclusion: Non-dermatophytes play a significant role in onychomycosis. On in vitro estimation, Itraconazole was the most sensitive drug, followed by terbinafine, fluconazole and griseofulvin.


2018 ◽  
Vol 56 (10) ◽  
Author(s):  
Hsuan-Chen Wang ◽  
Ming-I Hsieh ◽  
Pui-Ching Choi ◽  
Chi-Jung Wu

ABSTRACT This study compared the YeastOne and reference CLSI M38-A2 broth microdilution methods for antifungal susceptibility testing of Aspergillus species. The MICs of antifungal agents were determined for 100 Aspergillus isolates, including 54 Aspergillus fumigatus (24 TR34/L98H isolates), 23 A. flavus, 13 A. terreus, and 10 A. niger isolates. The overall agreement (within 2 2-fold dilutions) between the two methods was 100%, 95%, 92%, and 90% for voriconazole, posaconazole, itraconazole, and amphotericin B, respectively. The voriconazole geometric mean (GM) MICs were nearly identical for all isolates using both methods, whereas the itraconazole and posaconazole GM MICs obtained using the YeastOne method were approximately 1 dilution lower than those obtained using the reference method. In contrast, the amphotericin B GM MIC obtained using the YeastOne method was 3.3-fold higher than that observed using the reference method. For the 24 A. fumigatus TR34/L98H isolates assayed, the categorical agreement (classified according to the CLSI epidemiological cutoff values) was 100%, 87.5%, and 83.3% for itraconazole, voriconazole, and posaconazole, respectively. For four A. niger isolates, the itraconazole MICs were >8 μg/ml using the M38-A2 method due to trailing growth, whereas the corresponding itraconazole MICs obtained using the YeastOne method were all ≤0.25 μg/ml without trailing growth. These data suggest that the YeastOne method can be used as an alternative for azole susceptibility testing of Aspergillus species and for detecting the A. fumigatus TR34/L98H isolates but that this method fails to detect A. niger isolates exhibiting trailing growth with itraconazole. Additionally, for isolates with azole MICs that approach or that are at susceptibility breakpoints or with high amphotericin B MICs detected using the YeastOne method, further MIC confirmation using the reference CLSI method is needed.


2018 ◽  
Vol 12 (02) ◽  
pp. 102-108 ◽  
Author(s):  
Nurul Azmawati Mohamed ◽  
Siva Gowri Pathmanathan ◽  
Hazilawati Hussin ◽  
Adilahtul Bushro Zaini

Introduction: Invasive Candida infections cause significant mortality and morbidity worldwide. Information on recent trends in species distribution and antifungal resistance in local settings is essential. Methodology: Yeast isolates identified through standard culture methods throughout 2014 and 2015 from Hospital Ampang, Malaysia were retrospectively studied. The antifungal susceptibility of Candida species was determined using colorimetric broth microdilution method and MIC values interpreted according to CLSI breakpoints. Results: Out of all the 149 yeast cultures collected, most were from blood (55.7%) and respiratory specimens (33.6%). Candida tropicalis was the most common (28.9%), followed by C. albicans (26.2%), C. parapsilosis (15.4%), C. glabrata (14.1%), Crytococcus neoformans (6.7%), Trichosporon asahi (3.4%), C. krusei (2.0%), C. famata, C. rugose, C. guilliermondii, C. dublinensis and Trichosporon spp. (0.7% each). Occurrence of C. tropicalis in candidaemia cases was significantly associated to presence of an underlying haematological disorder, while C. albicans isolates in blood were significantly found in absence of such disorders. The four most common Candida species isolated showed high susceptibility to amphotericin B (100%), anidulafungin (100%), micafungin (100%), caspofungin (98.4%), flucytosine (98.4%) and voriconazole (84.1%). However, drug susceptibility to itraconazole and fluconazole was comparatively lower (57.9% and 72.2%, respectively). C. glabrata and C. tropicalis were the least susceptible to these azoles. Conclusion: Prevalence of the high number of non-albicans Candida species with slight predominance of C. tropicalis over C. albicans was observed. Low susceptibility to itraconazole among C. glabrata and C. tropicalis isolates and to fluconazole among C. glabrata isolates warrants for continued surveillance to monitor emerging antifungal resistance.


2004 ◽  
Vol 46 (5) ◽  
pp. 239-241 ◽  
Author(s):  
Ana Graciela Ventura Antunes ◽  
Alessandro Comarú Pasqualotto ◽  
María Cristina Diaz ◽  
Pedro Alves d'Azevedo ◽  
Luiz Carlos Severo

Recent studies have shown differences in the epidemiology of invasive infections caused by Candida species worldwide. In the period comprising August 2002 to August 2003, we performed a study in Santa Casa Complexo Hospitalar, Brazil, to determine Candida species distribution associated with candidemia and their antifungal susceptibility profiles to amphotericin B, fluconazole and itraconazole. Antifungal susceptibility was tested according to the broth microdilution method described in the NCCLS (M27A-2 method). Only one sample from each patient was analyzed (the first isolate). Most of the episodes had been caused by species other than C. albicans (51.6%), including C. parapsilosis (25.8%), C. tropicalis (13.3%), C. glabrata (3.3%), C. krusei (1.7%), and others (7.5%). Dose-dependent susceptibility to itraconazole was observed in 14.2% of strains, and dose-dependent susceptibility to fluconazole was found in 1.6%. Antifungal resistance was not found, probably related to low use of fluconazole. Further epidemiological surveillance is needed.


2020 ◽  
Vol 221 (Supplement_2) ◽  
pp. S139-S147 ◽  
Author(s):  
Meng Xiao ◽  
Sharon C-A Chen ◽  
Fanrong Kong ◽  
Xiu-Li Xu ◽  
Li Yan ◽  
...  

Abstract Background Candidemia is the most common, serious fungal infection and Candida antifungal resistance is a challenge. We report recent surveillance of candidemia in China. Methods The study encompassed 77 Chinese hospitals over 3 years. Identification of Candida species was by mass spectrometry and DNA sequencing. Antifungal susceptibility was determined using the Clinical and Laboratory Standards Institute broth microdilution method. Results In total, 4010 isolates were collected from candidemia patients. Although C. albicans was the most common species, non-albicans Candida species accounted for over two-thirds of isolates, predominated C. parapsilosis complex (27.1%), C. tropicalis (18.7%), and C. glabrata complex (12.0%). Most C. albicans and C. parapsilosis complex isolates were susceptible to all antifungal agents (resistance rate <5%). However, there was a decrease in voriconazole susceptibility to C. glabrata sensu stricto over the 3 years and fluconazole resistance rate in C. tropicalis tripled. Amongst less common Candida species, over one-third of C. pelliculosa isolates were coresistant to fluconazole and 5-flucytocine, and >56% of C. haemulonii isolates were multidrug resistance. Conclusions Non-albicans Candida species are the predominant cause of candidemia in China. Azole resistance is notable amongst C. tropicalis and C. glabrata. Coresistance and multidrug resistance has emerged in less common Candida species.


1997 ◽  
Vol 41 (4) ◽  
pp. 863-865 ◽  
Author(s):  
G G Zhanel ◽  
J A Karlowsky ◽  
G A Harding ◽  
T V Balko ◽  
S A Zelenitsky ◽  
...  

The in vitro activities of LY-303366, a new semisynthetic echinocandin, and comparators amphotericin B, 5-fluorocytosine, fluconazole, and ketoconazole against 205 systemic isolates of Candida species, Cryptococcus neoformans, Blastomyces dermatitidis, and Aspergillus species were determined. LY-303366 had MICs of < or = 0.32 microg/ml for all Candida albicans (n = 99), Candida glabrata (n = 18), and Candida tropicalis (n = 10) isolates tested. LY-303366 was also active against Aspergillus species (minimum effective concentration at which 90% of the isolates are inhibited, 0.02 microg/ml) (n = 20), was less active against Candida parapsilosis (MIC at which 90% of the isolates are inhibited [MIC90], 5.12 microg/ml) (n = 10), and was inactive against C. neoformans (MIC90, >10.24 microg/ml) (n = 15) and B. dermatitidis (MIC90, 16 microg/ml) (n = 29).


Author(s):  
Sahar Hivary ◽  
Mahnaz Fatahinia ◽  
Marzieh Halvaeezadeh ◽  
Ali Zarei Mahmoudabadi

Background and Objectives: Black Aspergillus strains including, Aspergillus niger and A. tubingensis, are the most cause of otomycosis with worldwide distribution. Although, amphotericin B was a Gold standard for the treatment of invasive fungal infection for several decades, it gradually replaced by fluconazole and /or voriconazole. Moreover, luliconazole, appears to offer the best potential for in vitro activity against black Aspergillus strains. The aim of the present study was to compare the in vitro activity luliconazole, with commonly used antifungals against clinical and environmental strains of black Aspergillus. Materials and Methods: Sixty seven (37 clinical and 30 environmental) strains of black Aspergillus were identified using morphological and molecular technique (β-Tubulin gene). In addition, antifungal susceptibility test was applied according to CLSI M38 A2. The results were reported as minimum inhibitory concentration (MIC) or minimum effective concentration (MEC) range, MIC50 or MEC50, MIC90 or MEC90 and MIC geometric (GM) or MECGM. Results: Aspergillus niger was the common isolate followed by, A. tubingensis in both clinical and environmental strains. The lowest MIC range, MIC50, MIC90, and MICGM was attributed to luliconazole in clinical strains. The highest resistant rate was found in amphotericin B for both clinical (86.5%) and environmental (96.7%) strains whereas 54.1% of clinical and 30% of environmental isolates were resistant to caspofungin. Clinical strains of Aspergillus were 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. Conclusion: Luliconazole versus amphotericin B, voriconazole, posaconazole and caspofungin is a potent antifungal for Aspergillus Nigri complex. The in vitro extremely antifungal efficacy against black Aspergillus strains of luliconazole, is different from those of other used antifungals.


Author(s):  
Bilal Ahmad Wani ◽  
Mohd Rafiq Lone ◽  
Najmus Saqib

Background: In this study, our aim was to identify and isolate Candida species from patients admitted in ICU,s of our hospital and to determine their susceptibilities to various antifungal agents so as to find the local resistance pattern and guide for empirical treatment.Methods: In our study 37 strains of candida were isolated (4 Candida albicans, 33 Non-albicans Candida strains). Candida species were identified by conventional, biochemical and molecular methods. Antifungal susceptibility tests for amphotericin B, fluconazole, itraconazole, ketoconazole and voriconazole were performed with broth microdilution method and E- tests as described by National Committee for Clinical Laboratory Standards (NCCLS).Results: Out of 37 Candida strains, the most prevalent species were C. tropicalis (43.2%), C. parapsilosis (24.3%), C. krusei (16.2%), C. albicans (10.8%), and C. glabrata (2.7%). Among all strains four strains (10.8 %) were resistant, two Candida albicans where found resistant to fluconazole one Candida krusei and one Candida parapsilosis were found to be resistant to all azoles.Conclusions: Candidemia continues to be associated with substantial morbidity and mortality and non albicans Candida species are the commonly isolated pathogen from those patients admitted in tertiary care hospitals in Indian scenario. Thus, it is imperative to perform antifungal susceptibility to select appropriate and effective antifungal therapy.


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