scholarly journals Molecular identification and antifungal susceptibility patterns of dermatophytes isolated from companion animals with clinical symptoms of dermatophytosis

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Farzad Katiraee ◽  
Yasaman Kouchak Kosari ◽  
Minoo Soltani ◽  
Hojjatollah Shokri ◽  
Mohammad Hassan Minooieanhaghighi
Keyword(s):  
Clinical Symptoms ◽  
Geometric Mean ◽  
Antifungal Susceptibility ◽  
Companion Animals ◽  
Molecular Study ◽  
Skin Lesions ◽  
Closely Related Species ◽  
Common Skin ◽  
One Year

Abstract Introduction Dermatophytosis is a common skin disease in cats and dogs caused by Microsporum and Trichophyton fungi. Species identification and knowledge of their antifungal susceptibility are therapeutically and epidemiologically important. This study assessed the prevalence of feline and canine dermatophytosis in Iran, identified the aetiological agents molecularly and tested their antifungal susceptibility. Material and Methods A total of 308 companion animals (134 dogs and 174 cats) with skin lesions were examined from March 2015 to March 2018. Hair and skin samples were examined by microscopy with 20% KOH and cultured on Sabouraud dextrose agar with cycloheximide and chloramphenicol. Fungal isolates were confirmed by sequencing of the internal transcribed spacer (ITS) r-DNA region. The antifungal susceptibility of dermatophytes was tested by broth microdilution assay using standard drugs. Results Dermatophytes were found in 130 (42.2%) samples, 62 of them feline and 68 canine. Based on sequencing of all strains, M. canis (78.5%, P<0.05), M. gypseum (10.7%), and T. mentagrophytes (10.7%) were the dermatophytes isolated. The non-dermatophyte species Nannizziopsis vriesii was also isolated from two feline dermatomycosis cases. Dogs and cats younger than one year (61.5%) showed a statistically significantly higher prevalence of infection (P<0.05). Caspofungin produced the lowest geometric mean MIC at 0.0018 μg/mL, followed by ketoconazole, terbinafine, itraconazole, miconazole, griseofulvin, clotrimazole and fluconazole, in a 0.038–1.53 μg/mL range. Conclusion This is the first molecular study to identify the causes of pet dermatophytosis in north-western Iran. ITS-PCR was shown to be a useful and reliable method for the identification of closely related species of dermatophytes in clinical and epidemiological settings. The lowest MIC of caspofungin indicated that this drug was the most potent in vitro.

scholarly journals The Emerging Terbinafine-Resistant Trichophyton Epidemic: What Is the Role of Antifungal Susceptibility Testing?

Dermatology ◽  
2021 ◽  
pp. 1-20
Author(s):  
Julia J. Shen ◽  
Maiken C. Arendrup ◽  
Shyam Verma ◽  
Ditte Marie L. Saunte
Keyword(s):  
Gene Mutation ◽  
Susceptibility Testing ◽  
Geometric Mean ◽  
Antifungal Susceptibility ◽  
Antifungal Susceptibility Testing ◽  
Squalene Epoxidase ◽  
Exclusion Criteria ◽  
Huge Variation

<b><i>Background:</i></b> Dermatophytosis is commonly encountered in the dermatological clinics. The main aetiological agents in dermatophytosis of skin and nails in humans are <i>Trichophyton</i> (<i>T</i>.) <i>rubrum</i>, <i>T. mentagrophytes</i> and <i>T. interdigitale</i> (former <i>T. mentagrophytes-</i>complex). Terbinafine therapy is usually effective in eradicating infections due to these species by inhibiting their squalene epoxidase (SQLE) enzyme, but increasing numbers of clinically resistant cases and mutations in the SQLE gene have been documented recently. Resistance to antimycotics is phenotypically determined by antifungal susceptibility testing (AFST). However, AFST is not routinely performed for dermatophytes and no breakpoints classifying isolates as susceptible or resistant are available, making it difficult to interpret the clinical impact of a minimal inhibitory concentration (MIC). <b><i>Summary:</i></b> PubMed was systematically searched for terbinafine susceptibility testing of dermatophytes on October 20, 2020, by two individual researchers. The inclusion criteria were <i>in vitro</i> terbinafine susceptibility testing of <i>Trichophyton (T.) rubrum</i>, <i>T. mentagrophytes</i> and <i>T. interdigitale</i> with the broth microdilution technique. The exclusion criteria were non-English written papers. Outcomes were reported as MIC range, geometric mean, modal MIC and MIC<sub>50</sub> and MIC<sub>90</sub> in which 50 or 90% of isolates were inhibited, respectively. The reported MICs ranged from &#x3c;0.001 to &#x3e;64 mg/L. The huge variation in MIC is partly explained by the heterogeneity of the <i>Trichophyton</i> isolates, where some originated from routine specimens (wild types) whereas others came from non-responding patients with a known SQLE gene mutation. Another reason for the great variation in MIC is the use of different AFST methods where MIC values are not directly comparable. High MICs were reported particularly in isolates with SQLE gene mutation. The following SQLE alterations were reported: F397L, L393F, L393S, H440Y, F393I, F393V, F415I, F415S, F415V, S443P, A448T, L335F/A448T, S395P/A448T, L393S/A448T, Q408L/A448T, F397L/A448T, I121M/V237I and H440Y/F484Y in terbinafine-resistant isolates.

scholarly journals Antifungal Susceptibility Patterns of Opportunistic Fungi in the Genera Verruconis and Ochroconis

2014 ◽  
Vol 58 (6) ◽  
pp. 3285-3292 ◽  
Author(s):  
S. Seyedmousavi ◽  
K. Samerpitak ◽  
A. J. M. M. Rijs ◽  
W. J. G. Melchers ◽  
J. W. Mouton ◽  
...  
Keyword(s):  
Geometric Mean ◽  
Antifungal Susceptibility ◽  
Species Level ◽  
Phylogenetic Distance ◽  
Dematiaceous Fungi ◽  
Opportunistic Fungi ◽  
Content Type ◽  
Broth Microdilution Method ◽  
Susceptibility Patterns

ABSTRACTSpecies ofVerruconisand species ofOchroconisare dematiaceous fungi generally found in the environment but having the ability to infect humans, dogs, cats, poultry, and fish. This study presents the antifungal susceptibility patterns of these fungi at the species level. Forty strains originating from clinical and environmental sources were phylogenetically identified at the species level by using sequences of the ribosomal DNA internal transcribed spacer (rDNA ITS).In vitroantifungal susceptibility testing was performed against eight antifungals, using the Clinical and Laboratory Standards Institute (CLSI) broth microdilution method. The geometric mean MICs for amphotericin B (AMB), flucytosine (5FC), fluconazole (FLC), itraconazole (ITC), voriconazole (VRC), and posaconazole (POS) and minimum effective concentrations (MECs) for caspofungin (CAS) and anidulafungin (AFG) across theOchroconisandVerruconisspecies were as follows, in increasing order. ForVerruconisspecies, the values (μg/ml) were as follows: AFG, 0.04; POS, 0.25; ITC, 0.37; AMB, 0.50; CAS, 0.65; VRC, 0.96; 5FC, 10.45; and FLC, 47.25. ForOchroconisspecies, the values (μg/ml) were as follows: AFG, 0.06; POS, 0.11; CAS, 0.67; VRC, 2.76; ITC, 3.94; AMB, 5.68; 5FC, 34.48; and FLC, 61.33. Antifungal susceptibility ofOchroconisandVerruconiswas linked with phylogenetic distance and thermotolerance. Echinocandins and POS showed the greatestin vitroactivity, providing possible treatment options forOchroconisandVerruconisinfections.

In vitro antifungal susceptibility of Malassezia pachydermatis from dogs with and without skin lesions

2012 ◽  
Vol 155 (2-4) ◽  
pp. 395-398 ◽  
Author(s):  
Claudia Cafarchia ◽  
Luciana A. Figueredo ◽  
Roberta Iatta ◽  
Maria Teresa Montagna ◽  
Domenico Otranto
Keyword(s):  
Antifungal Susceptibility ◽  
Skin Lesions ◽  
Malassezia Pachydermatis ◽  
In Vitro Antifungal Susceptibility

scholarly journals Coelomycetous Fungi in the Clinical Setting: Morphological Convergence and Cryptic Diversity

2016 ◽  
Vol 55 (2) ◽  
pp. 552-567 ◽  
Author(s):  
Nicomedes Valenzuela-Lopez ◽  
Deanna A. Sutton ◽  
José F. Cano-Lira ◽  
Katihuska Paredes ◽  
Nathan Wiederhold ◽  
...  
Keyword(s):  
Large Subunit ◽  
Antifungal Susceptibility ◽  
Molecular Study ◽  
Morphological Characterization ◽  
Clinical Samples ◽  
Anatomical Site ◽  
Large Set ◽  
Content Type ◽  
Neoscytalidium Dimidiatum

ABSTRACTHuman infections by coelomycetous fungi are becoming more frequent and range from superficial to systemic dissemination. Traumatic implantation of contaminated plant material is the most common cause. The typical morphological feature of these fungi is the production of asexual spores (conidia) within fruiting bodies called conidiomata. This study aimed to determine the distribution of the coelomycetes in clinical samples by a phenotypic and molecular study of a large set of isolates received from a U.S. reference mycological institution and by obtaining thein vitroantifungal susceptibility pattern of nine antifungals against a selected group of isolates. A total of 230 isolates were identified by sequencing the D1 and D2 domains of the large subunit (LSU) nuclear ribosomal RNA (nrRNA) gene and by morphological characterization. Eleven orders of the phylumAscomycotawere identified:Pleosporales(the largest group; 66.1%),Botryosphaeriales(19.57%),Glomerellales(4.35%),Diaporthales(3.48%),Xylariales(2.17%),HysterialesandValsariales(0.87%), andCapnodiales,Helotiales,HypocrealesandMagnaporthales(0.43% each). The most prevalent species wereNeoscytalidium dimidiatum,Paraconiothyriumspp.,Phoma herbarum,Didymella heteroderae, andEpicoccum sorghinum. The most common anatomical site of isolation was superficial tissue (66.5%), followed by the respiratory tract (17.4%). Most of the isolates tested were susceptible to the majority of antifungals, and only flucytosine showed poor antifungal activity.

scholarly journals Susceptibility Patterns and Molecular Identification of Trichosporon Species

2005 ◽  
Vol 49 (10) ◽  
pp. 4026-4034 ◽  
Author(s):  
Juan L. Rodriguez-Tudela ◽  
Teresa M. Diaz-Guerra ◽  
Emilia Mellado ◽  
Virginia Cano ◽  
Cecilia Tapia ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Geometric Mean ◽  
Antifungal Susceptibility ◽  
Intergenic Spacer ◽  
Clinical Isolates ◽  
Rrna Genes ◽  
Correct Identification ◽  
Its Sequencing ◽  
Trichosporon Species

ABSTRACT The physiological patterns, the sequence polymorphisms of the internal transcriber spacer (ITS), and intergenic spacer regions (IGS) of the rRNA genes and the antifungal susceptibility profile were evaluated for their ability to identify Trichosporon spp. and their specificity for the identification of 49 clinical isolates of Trichosporon spp. Morphological and biochemical methodologies were unable to differentiate among the Trichosporon species. ITS sequencing was also unable to differentiate several species. However, IGS1 sequencing unambiguously identified all Trichosporon isolates. Following the results of DNA-based identification, Trichosporon asahii was the species most frequently isolated from deep sites (15 of 25 strains; 60%). In the main, other Trichosporon species were recovered from cutaneous samples. The majority of T. asahii, T. faecale, and T. coremiiforme clinical isolates exhibited resistance in vitro to amphotericin B, with geometric mean (GM) MICs >4 μg/ml. The other species of Trichosporon did not show high MICs of amphotericin B, and GM MICs were <1 μg/ml. Azole agents were active in vitro against the majority of clinical strains. The most potent compound in vitro was voriconazole, with a GM MIC ≤0.14 μg/ml. The sequencing of IGS correctly identified Trichosporon isolates; however, this technique is not available in many clinical laboratories, and strains should be dispatched to reference centers where these complex methods are available. Therefore, it seems to be more practical to perform antifungal susceptibility testing of all isolates belonging to Trichosporon spp., since correct identification could take several weeks, delaying the indication of an antifungal agent which exhibits activity against the infectious strain.

scholarly journals In VitroAntifungal Susceptibility of Yeast and Mold Phases of Isolates of Dimorphic Fungal Pathogen Emergomyces africanus (Formerly Emmonsia sp.) from HIV-Infected South African Patients

2017 ◽  
Vol 55 (6) ◽  
pp. 1812-1820 ◽  
Author(s):  
Tsidiso G. Maphanga ◽  
Erika Britz ◽  
Thokozile G. Zulu ◽  
Ruth S. Mpembe ◽  
Serisha D. Naicker ◽  
...  
Keyword(s):  
Amphotericin B ◽  
Fungal Pathogen ◽  
Geometric Mean ◽  
Antifungal Susceptibility ◽  
Outcome Data ◽  
Internal Transcribed Spacer Region ◽  
Content Type ◽  
Susceptibility Data ◽  
Custom Made

ABSTRACTDisseminated emmonsiosis is an important AIDS-related mycosis in South Africa that is caused byEmergomycesafricanus, a newly described and renamed dimorphic fungal pathogen.In vitroantifungal susceptibility data can guide management. Identification of invasive clinical isolates was confirmed phenotypically and by sequencing of the internal transcribed spacer region. Yeast and mold phase MICs of fluconazole, voriconazole, itraconazole, posaconazole, caspofungin, anidulafungin, micafungin, and flucytosine were determined with custom-made frozen broth microdilution (BMD) panels in accordance with Clinical and Laboratory Standards Institute recommendations. MICs of amphotericin B, itraconazole, posaconazole, and voriconazole were determined by Etest. Fifty uniqueE. africanusisolates were tested. The yeast and mold phase geometric mean (GM) BMD and Etest MICs of itraconazole were 0.01 mg/liter. The voriconazole and posaconazole GM BMD MICs were 0.01 mg/liter for both phases, while the GM Etest MICs were 0.001 and 0.002 mg/liter, respectively. The fluconazole GM BMD MICs were 0.18 mg/liter for both phases. The GM Etest MICs of amphotericin B, for the yeast and mold phases were 0.03 and 0.01 mg/liter. The echinocandins and flucytosine had very limitedin vitroactivity. Treatment and outcome data were available for 37 patients; in a multivariable model including MIC data, only isolation from blood (odds ratio [OR], 8.6; 95% confidence interval [CI], 1.3 to 54.4;P= 0.02) or bone marrow (OR, 12.1; 95% CI, 1.2 to 120.2;P= 0.03) (versus skin biopsy) was associated with death.In vitrosusceptibility data support the management of disseminated emmonsiosis with amphotericin B, followed by itraconazole, voriconazole, or posaconazole. Fluconazole was a relatively less potent agent.

scholarly journals A Case of Terbinafine-Resistant Tinea Cruris Caused by Trichophyton tonsurans

2021 ◽  
Vol 2021 ◽  
pp. 1-3
Author(s):  
Alireza Firooz ◽  
Ensieh Lotfali ◽  
Mahsa Fattahi ◽  
Maryam Fattahi ◽  
Akram Miramin Mohammadi ◽  
...  
Keyword(s):  
Present Report ◽  
Antifungal Susceptibility ◽  
Skin Lesions ◽  
Causative Organism ◽  
Trichophyton Tonsurans ◽  
Antifungal Stewardship ◽  
Similar Treatment ◽  
History Of ◽  
One Year ◽  
Susceptibility Assay

A 26-year-old male patient referred to our center with a history of extremely itchy crusted skin lesions in his groins for one year. Moreover, his friend, a 25-year-old male, also developed similar lesions in the groin after using the shared pool, whose condition also did not improve with similar treatment. A regular mycology test (direct and culture test) was performed, as well as molecular examination. The antifungal susceptibility assay to terbinafine, itraconazole, posaconazole, fluconazole, and voriconazole was conducted according to the Clinical and Laboratory Standards Institute M38 third ed. The sequencing study identified T. tonsurans as the causative organism in both patients. The abovementioned organism isolated from both patients displayed resistance against terbinafine and fluconazole (MIC ≥ 4 µg/ml and MIC ≥ 8 µg/ml, respectively). Moreover, the susceptibility of both subjects to posaconazole (0.313 µg/ml), voriconazole (0.25–0.0625 µg/ml), and (1 µg/ml) itraconazole increased. The present report aimed to emphasize the increase in antifungal resistance and a demand for antifungal stewardship, to control this public health threat.

scholarly journals In Vitro Susceptibility of Talaromyces Marneffei In Malaysia: Comparison of Yeast and Mycelial Phases

2021 ◽  
Author(s):  
Xue Ting Tan ◽  
Nurliyana binti Mohd Shuhairi ◽  
Stephanie Jane Ginsapu ◽  
Surianti Binti Shukor ◽  
Fairuz Binti Amran
Keyword(s):  
Amphotericin B ◽  
Geometric Mean ◽  
Antifungal Susceptibility ◽  
Etiologic Agent ◽  
Mycelial Form ◽  
In Vitro Susceptibility ◽  
Terbinafine Hydrochloride ◽  
Acquired Immunodeficiency ◽  
Immunodeficiency Syndrome

Abstract Talaromyces marneffei is an etiologic agent of talaromycosis. It can cause serious complications and death in immunocompromised patients, particularly in acquired immunodeficiency syndrome (AIDS) patients. This infectious disease is endemic in Southeast Asia including Malaysia. To date, published reports on the antifungal susceptibility profile of T. marneffei is very limited. The objective of this study is to determine the minimum inhibitory concentration (MIC) of T. marneffei in yeast and mycelial phases in Malaysia. In the year 2020, 27 clinical strains of T. marneffei were received from various hospitals in Malaysia. The identification was carried out using microscopic, macroscopic and molecular methods. Following that, the susceptibility of each isolate in both yeast and mycelial form to thirteen common antifungals was performed according to the broth microdilution in Clinical & Laboratory Standards Institute (CLSI) M38 method. The antifungals tested were anidulafungin, micafungin sodium, caspofungin diacetate, 5-fluorocytosine, amphotericin B and terbinafine hydrochloride, posaconazole, voriconazole, itraconazole, ketoconazole, ravuconazole, clotrimazole and isavuconazole. The geometric mean of all antifungals other than anidulafungin, micafungin sodium, caspofungin diacetate and 5-fluorocytosine against T. marneffei mould (mycelial) were >2 μg/ml. However, the geometric mean of all antifungals against T. marneffei yeast was <2 μg/ml. Our in vitro data suggests promising activities of amphotericin B, terbinafine hydrochloride, posaconazole, voriconazole, itraconazole, ketoconazole, ravuconazole, clotrimazole and isavuconazole against yeast and mould phases of T. marneffei.

scholarly journals Epidemiology and Antifungal Susceptibility of BloodstreamCandidaIsolates in Quebec: Report on 453 Cases between 2003 and 2005

2008 ◽  
Vol 19 (1) ◽  
pp. 55-62 ◽  
Author(s):  
Guy St-Germain ◽  
Michel Laverdière ◽  
René Pelletier ◽  
Pierre René ◽  
Anne-Marie Bourgault ◽  
...  
Keyword(s):  
Candida Parapsilosis ◽  
Inhibitory Concentration ◽  
Geometric Mean ◽  
Antifungal Susceptibility ◽  
Bloodstream Infections ◽  
Population Based ◽  
Intravascular Catheter ◽  
Fluconazole Resistant ◽  
Candida Lusitaniae

BACKGROUND: Between May 2003 and April 2005, a population-based surveillance ofCandidabloodstream infections was conducted in Quebec. A total of 453 episodes of candidemia (464 yeast isolates) from 54 participating hospitals were studied.RESULTS: The annual incidence rate was three per 100,000 population. Global hospital mortality was 38%. The most common predisposing factors were the presence of an intravascular catheter (80%), use of antibacterial therapy (67%), stay in an intensive care unit (49%), use of parenteral nutrition (32%) and intra-abdominal surgery (31%). Fluconazole alone or in association with other antifungals was used for treatment in over 80% of cases.Candida albicanscomprised 62% of isolates, followed byCandida glabrata(17%),Candida parapsilosis(9%),Candida tropicalis(5%),Candida lusitaniae(3%) andCandida krusei(3%). Of the 288C albicansisolates, seven (2%) were resistant to flucytosine, one to fluconazole and none to itraconazole or voriconazole. Of the 75 non-C albicansspecies isolates with reduced susceptibility to fluconazole (minimum inhibitory concentration [MIC] 16 μg/mL or greater), none were susceptible to itraconazole (MIC 0.12 mg/L or lower), whereas 71 (95%) were susceptible to voriconazole (MIC 1 μg/mL or lower). However, only five of 12 (42%) fluconazole-resistant isolates were susceptible to voriconazole. Posaconazole, ravuconazole and caspofungin displayed a broad spectrum of activity against these isolates, with MICs of 1 mg/L or lower in 56%, 92% and 100% of isolates, respectively. Overall, a correlation (r2>0.87) was observed among increasing fluconazole MICs and the geometric mean MICs of itraconazole, voriconazole, posaconazole and ravuconazole.CONCLUSIONS: These surveillance results when compared with those of the 1993 to 1995 survey confirm little variation in the distribution of species causing invasiveCandidainfection over a 10-year period in Quebec, as well as the continuous excellent overall in vitro activity of fluconazole.

scholarly journals In Vitro Activities of New Antifungal Agents against Chaetomium spp. and Inoculum Standardization

2003 ◽  
Vol 47 (10) ◽  
pp. 3161-3164 ◽  
Author(s):  
Carolina Serena ◽  
Montserrat Ortoneda ◽  
Javier Capilla ◽  
F. Javier Pastor ◽  
Deanna A. Sutton ◽  
...  
Keyword(s):  
Mortality Rate ◽  
Related Species ◽  
Antifungal Agents ◽  
Geometric Mean ◽  
Etiological Agent ◽  
Immunocompromised Patients ◽  
Closely Related Species ◽  
Microdilution Method ◽  
Human Infections

ABSTRACT Chaetomium is an unusual etiological agent of human infections, but the mortality rate among immunocompromised patients is considerably greater than that among nonimmunocompromised individuals. We investigated the in vitro antifungal susceptibilities to novel antifungal agents of 19 strains belonging to three species of Chaetomium which have been involved in human infections, i.e., Chaetomium globosum, C. atrobrunneum, and C. nigricolor, and one strain of the closely related species Achaetomium strumarium. A modification of the NCCLS reference microdilution method (M38-A) was used to evaluate the in vitro activities of ravuconazole, voriconazole, albaconazole, and micafungin. Micafungin was not active at all, while the geometric mean MICs and minimum effective concentrations of the three triazoles were less than 0.5 and 0.4 μg/ml, respectively.

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