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1.
Clin Microbiol Rev ; 37(2): e0007423, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38602408

ABSTRACT

SUMMARYFungal infections are on the rise, driven by a growing population at risk and climate change. Currently available antifungals include only five classes, and their utility and efficacy in antifungal treatment are limited by one or more of innate or acquired resistance in some fungi, poor penetration into "sequestered" sites, and agent-specific side effect which require frequent patient reassessment and monitoring. Agents with novel mechanisms, favorable pharmacokinetic (PK) profiles including good oral bioavailability, and fungicidal mechanism(s) are urgently needed. Here, we provide a comprehensive review of novel antifungal agents, with both improved known mechanisms of actions and new antifungal classes, currently in clinical development for treating invasive yeast, mold (filamentous fungi), Pneumocystis jirovecii infections, and dimorphic fungi (endemic mycoses). We further focus on inhaled antifungals and the role of immunotherapy in tackling fungal infections, and the specific PK/pharmacodynamic profiles, tissue distributions as well as drug-drug interactions of novel antifungals. Finally, we review antifungal resistance mechanisms, the role of use of antifungal pesticides in agriculture as drivers of drug resistance, and detail detection methods for antifungal resistance.


Subject(s)
Antifungal Agents , Drug Resistance, Fungal , Invasive Fungal Infections , Antifungal Agents/therapeutic use , Antifungal Agents/pharmacokinetics , Antifungal Agents/pharmacology , Humans , Invasive Fungal Infections/drug therapy , Invasive Fungal Infections/microbiology , Fungi/drug effects , Animals , Treatment Outcome
2.
J Antimicrob Chemother ; 78(6): 1488-1494, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37100456

ABSTRACT

OBJECTIVES: Although perceived as a rare clinical entity, recent studies have noted the emergence of MDR C. parapsilosis (MDR-Cp) isolates from single patients (resistant to both azole and echinocandins). We previously reported a case series of MDR-Cp isolates carrying a novel FKS1R658G mutation. Herein, we identified an echinocandin-naive patient infected with MDR-Cp a few months after the previously described isolates. WGS and CRISPR-Cas9 editing were used to explore the origin of the new MDR-Cp isolates, and to determine if the novel mutation confers echinocandin resistance. METHODS: WGS was applied to assess the clonality of these isolates and CRISPR-Cas9 editing and a Galleria mellonella model were used to examine whether FKS1R658G confers echinocandin resistance. RESULTS: Fluconazole treatment failed, and the patient was successfully treated with liposomal amphotericin B (LAMB). WGS proved that all historical and novel MDR-Cp strains were clonal and distant from the fluconazole-resistant outbreak cluster in the same hospital. CRISPR-Cas9 editing and G. mellonella virulence assays confirmed that FKS1R658G confers echinocandin resistance in vitro and in vivo. Interestingly, the FKS1R658G mutant showed a very modest fitness cost compared with the parental WT strain, consistent with the persistence of the MDR-Cp cluster in our hospital. CONCLUSIONS: Our study showcases the emergence of MDR-Cp isolates as a novel threat in clinical settings, which undermines the efficacy of the two most widely used antifungal drugs against candidiasis, leaving only LAMB as a last resort. Additionally, surveillance studies and WGS are warranted to effectively establish infection control and antifungal stewardship strategies.


Subject(s)
Antifungal Agents , Candidemia , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Candida parapsilosis/genetics , Fluconazole/pharmacology , Drug Resistance, Fungal , Echinocandins/pharmacology , Echinocandins/therapeutic use , Candidemia/drug therapy , Candidemia/epidemiology , Microbial Sensitivity Tests
3.
Bioinformatics ; 37(11): 1610-1612, 2021 07 12.
Article in English | MEDLINE | ID: mdl-33079985

ABSTRACT

MOTIVATION: Sequence analyses oriented to investigate specific features, patterns and functions of protein and DNA/RNA sequences usually require tools based on graphic interfaces whose main characteristic is their intuitiveness and interactivity with the user's expertise, especially when curation or primer design tasks are required. However, interface-based tools usually pose certain computational limitations when managing large sequences or complex datasets, such as genome and transcriptome assemblies. Having these requirments in mind we have developed SeqEditor an interactive software tool for nucleotide and protein sequences' analysis. RESULT: SeqEditor is a cross-platform desktop application for the analysis of nucleotide and protein sequences. It is managed through a Graphical User Interface and can work either as a graphical sequence browser or as a fasta task manager for multi-fasta files. SeqEditor has been optimized for the management of large sequences, such as contigs, scaffolds or even chromosomes, and includes a GTF/GFF viewer to visualize and manage annotation files. In turn, this allows for content mining from reference genomes and transcriptomes with similar efficiency to that of command line tools. SeqEditor also incorporates a set of tools for singleplex and multiplex PCR primer design and pooling that uses a newly optimized and validated search strategy for target and species-specific primers. All these features make SeqEditor a flexible application that can be used to analyses complex sequences, design primers in PCR assays oriented for diagnosis, and/or manage, edit and personalize reference sequence datasets. AVAILABILITYAND IMPLEMENTATION: SeqEditor was developed in Java using Eclipse Rich Client Platform and is publicly available at https://gpro.biotechvana.com/download/SeqEditor as binaries for Windows, Linux and Mac OS. The user manual and tutorials are available online at https://gpro.biotechvana.com/tool/seqeditor/manual. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Subject(s)
Genome , Software , Amino Acid Sequence , Humans , Sequence Analysis , Sequence Analysis, Protein
4.
Mycoses ; 65(10): 960-968, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35979737

ABSTRACT

BACKGROUND: Galactomannan Enzyme Immunoassay (GM-EIA) is proved to be a cornerstone in the diagnosis of COVID-19-associated pulmonary aspergillosis (CAPA), its use is limited in middle and low-income countries, where the application of simple and rapid test, including Galactomannan Lateral Flow Assay (GM-LFA), is highly appreciated. Despite such merits, limited studies directly compared GM-LFA with GM-EIA. Herein we compared the diagnostic features of GM-LFA, GM-EIA and bronchoalveolar lavage (BAL) culture for CAPA diagnosis in Iran, a developing country. MATERIALS/METHODS: Diagnostic performances of GM-LFA and GM-EIA in BAL (GM indexes ≥1) and serum (GM indexes >0.5), i.e. sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) and areas under the curve (AUC), were evaluated using BAL (n = 105) and serum (n = 101) samples from mechanically ventilated COVID-19 patients in intensive care units. Patients were classified based on the presence of host factors, radiological findings and mycological evidences according to 2020 ECMM/ISHAM consensus criteria for CAPA diagnosis. RESULTS: The Aspergillus GM-LFA for serum and BAL samples showed a sensitivity of 56.3% and 60.6%, specificity of 94.2% and 88.9%, PPV of 81.8% and 71.4%, NPV of 82.3% and 83.1%, when compared with BAL culture, respectively. GM-EIA showed sensitivities of 46.9% and 54.5%, specificities of 100% and 91.7%, PPVs of 100% and 75%, NPVs of 80.2% and 81.5% for serum and BAL samples, respectively. CONCLUSION: Our study found GM-LFA as a reliable simple and rapid diagnostic tool, which could circumvent the shortcomings of culture and GM-EIA and be pivotal in timely initiation of antifungal treatment.


Subject(s)
COVID-19 , Invasive Pulmonary Aspergillosis , Pulmonary Aspergillosis , Antifungal Agents , Bronchoalveolar Lavage Fluid/microbiology , COVID-19/diagnosis , COVID-19 Testing , Galactose/analogs & derivatives , Humans , Immunoenzyme Techniques , Invasive Pulmonary Aspergillosis/diagnosis , Invasive Pulmonary Aspergillosis/microbiology , Mannans , Sensitivity and Specificity
5.
Mycopathologia ; 187(2-3): 169-180, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35157189

ABSTRACT

Knowledge about the clinical characteristics and prognostic factors of Talaromyces marneffei infection in children is limited, especially in HIV-positive children. We performed a retrospective study of all HIV-positive pediatric inpatients with T. marneffei infection in a tertiary hospital in Southern China between 2014 and 2019 and analyzed the related risk factors of poor prognosis using logistic regression. Overall, 28 cases were enrolled and the prevalence of talaromycosis in AIDS children was 15.3% (28/183). The median age of the onset was 8 years (range: 1-14 years). The typical manifestation of skin lesion with central umbilication was not common (21.4%). All the children had very low CD4+ cell counts (median 13.5 cells/µL, range: 3-137 cells/µL) on admission. 92.9% children were misdiagnosed and talaromycosis was only noted after positivity for HIV infection. 89.3% diagnoses of T. marneffei infections were based on positive blood cultures, with a long culture time (median 7 days, range from 3-14 days). The sensitivity of fungus 1,3-ß-D-glucan assay was 63.2%. Amphotericin B was superior to itraconazole in the induction antifungal therapy of talaromycosis in HIV-positive children. A six-month follow-up revealed a 28.6% mortality. Lower ratio of CD4+/CD8+ and amphotericin B treatment not over 7 days predicted poor prognosis. Our retrospective study provided an overview and update on the current knowledge of talaromycosis in HIV-positive children. Pediatricians in endemic areas should be aware of mycoses to prevent misdiagnosis. 1,3-ß-D-glucan assay did not show optimal sensitivity. Amphotericin B treatment over 7 days can improve poor prognosis.


Subject(s)
HIV Infections , Mycoses , Talaromyces , Adolescent , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Child , Child, Preschool , China/epidemiology , Glucans/therapeutic use , HIV Infections/drug therapy , Humans , Infant , Mycoses/diagnosis , Mycoses/drug therapy , Mycoses/epidemiology , Prognosis , Retrospective Studies
6.
J Antimicrob Chemother ; 76(2): 418-422, 2021 01 19.
Article in English | MEDLINE | ID: mdl-33175162

ABSTRACT

BACKGROUND: Echinocandin resistance rarely occurs in clinical Candida parapsilosis isolates and the underlying mechanism is unknown. OBJECTIVES: To determine the prevalence of echinocandin resistance and the underlying mechanism for a large collection of C. parapsilosis blood isolates and to determine whether the echinocandin-resistant isolates were clonally related. METHODS: C. parapsilosis blood isolates (n = 213) were subjected to antifungal susceptibility testing (CLSI M27), for micafungin, anidulafungin, amphotericin B and, if appropriate, caspofungin. Hotspot (HS) 1 and HS2 of FKS1 were sequenced for all isolates (n = 213) and microsatellite typing was performed for echinocandin-resistant isolates. RESULTS: All isolates were susceptible to amphotericin B and two isolates were intermediate to anidulafungin (MIC = 4 mg/L), while micafungin resistance was noted in four isolates (MIC >8 mg/L); three of which were also fluconazole resistant and therefore were MDR. Interestingly, micafungin-resistant isolates, but not those intermediate to anidulafungin, carried novel mutation R658G in HS1 of Fks1p; three of which also harboured Y132F+K143R in Erg11. The first isolate (MICR1) was recovered in November 2017 from a patient admitted to paediatric gastroenterology who showed therapeutic failure under caspofungin treatment. MICR2-MICR4 were collected during 2018-19 and were recovered from three echinocandin-naive paediatric-surgery patients; the isolates shared the same genotype. CONCLUSIONS: Herein, for the first time (to the best of our knowledge), we identified micafungin-resistant C. parapsilosis blood isolates harbouring a novel mutation in HS1 of FKS1, which was likely attributable to in vitro micafungin resistance and in vivo caspofungin therapeutic failure. The acquisition of micafungin-resistant C. parapsilosis isolates in echinocandin-naive patients likely implicates clonal expansion, as supported by the close genetic relatedness of MICR2-MICR4.


Subject(s)
Antifungal Agents , Candida parapsilosis , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Child , Drug Resistance, Fungal , Echinocandins/pharmacology , Humans , Micafungin/pharmacology , Microbial Sensitivity Tests , Mutation
7.
Crit Rev Microbiol ; 47(6): 679-698, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34115962

ABSTRACT

Species of Trichosporon and related genera are widely used in biotechnology and, hence, many species have their genome sequenced. Importantly, yeasts of the genus Trichosporon have been increasingly identified as a cause of life-threatening invasive trichosporonosis (IT) in humans and are associated with an exceptionally high mortality rate. Trichosporon spp. are intrinsically resistant to frontline antifungal agents, which accounts for numerous reports of therapeutic failure when echinocandins are used to treat IT. Moreover, these fungi have low sensitivity to polyenes and azoles and, therefore, are potentially regarded as multidrug-resistant pathogens. However, despite the clinical importance of Trichosporon spp., our understanding of their antifungal resistance mechanisms is quite limited. Furthermore, antifungal susceptibility testing is not standardized, and there is a lack of interpretive epidemiological cut-off values for minimal inhibitory concentrations to distinguish non-wild type Trichosporon isolates. The route of infection remains obscure and detailed clinical and environmental studies are required to determine whether the Trichosporon infections are endogenous or exogenous in nature. Although our knowledge on effective IT treatments is rather limited and future randomized clinical trials are required to identify the best antifungal agent, the current paradigm advocates the use of voriconazole, removal of central venous catheters and recovery from neutropenia.


Subject(s)
Trichosporon , Trichosporonosis , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Drug Resistance, Fungal , Echinocandins , Fungi , Humans , Microbial Sensitivity Tests , Trichosporon/genetics , Trichosporonosis/drug therapy
8.
Med Mycol ; 59(5): 422-430, 2021 May 04.
Article in English | MEDLINE | ID: mdl-32692816

ABSTRACT

Systematic candidemia studies, especially in southern Iran, are scarce. In the current prospective study, we investigated candidemia in three major healthcare centers of Shiraz, the largest city in southern Iran. Yeast isolates from blood and other sterile body fluids were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and subjected to antifungal susceptibility testing (AFST) using the broth microdilution method. Clinical data were retrieved from patients' medical records. In total, 113 yeast isolates were recovered from 109 patients, over 60% of whom received fluconazole. Antifungal drugs were prescribed without considering species identification or AFST. The all-cause mortality rate was 28%. Almost 30% of the patients were from intensive care units (ICUs). Candida albicans (56/113; 49.5%) was the most prevalent species followed by C. glabrata (26/113; 23%), C. parapsilosis (13/113; 11.5%), C. tropicalis (7/113; 6.2%), and C. dubliniensis (5/113; 4.4%). Only five isolates showed antifungal resistance or decreased susceptibility to fluconazole: one C. orthopsilosis isolate from an azole-naïve patient and two C. glabrata, one C. albicans, and one C. dubliniensis isolates from patients treated with azoles, who developed therapeutic failure against azoles later. Our results revealed a low level of antifungal resistance but a notable rate of azole therapeutic failure among patients with candidemia due to non-albicans Candida species, which threaten the efficacy of fluconazole, the most widely used antifungal in southern regions of Iran. Candidemia studies should not be confined to ICUs and treatment should be administered based on species identification and AFST results.


Landscape of candidemia is blurred in Iran, and only two studies from Tehran have extensively explored the epidemiology of candidemia. However, candidemia data from the other regions are notoriously scarce, which precludes from reaching a consensus regarding species distribution, the burden of antifungal resistance, and the clinical features of infected patients. Therefore, we conducted the current prospective candidemia study in Shiraz, one of the largest cities located in the south of Iran, from April 2016 to April 2018. More than 63% of the candidemia infections were treated by fluconazole and species identification and antifungal susceptibility testing were not used for decision making regarding the choice of antifungal treatment. Approximately 70% of the candidemia cases occurred in the wards outside of the ICUs. Candida albicans, C. glabrata, C. parapsilosis, C. tropicalis, and C. dubliniensis were the five leading causative agents of candidemia. Antifungal resistance was rare and fluconazole resistance and/or non-wild type phenotypes were noticed in five isolates, only one was C. albicans and the rest were non-albicans Candida (NAC) species, including C. glabrata, C. dubliniensis, and C. orthopsilosis. Except for C. orthopsilosis, which was isolated from an azole-naïve patient, the rest of isolates were recovered from patients treated with azoles and all showed therapeutic failure to azoles. Collectively, our data will complete the candidemia picture in Iran and show that, although the level of resistance was rare, the therapeutic failure was notable among NAC species, which threatens the efficacy of fluconazole, the most widely used antifungal in Southern regions of Iran. Moreover, we showed that candidemia is poorly managed in Iran since species identification tools along with antifungal susceptibility testing were not used to select appropriate antifungal treatment.


Subject(s)
Antifungal Agents/pharmacology , Candida/drug effects , Candida/isolation & purification , Candidemia/epidemiology , Candidemia/microbiology , Adolescent , Adult , Aged , Aged, 80 and over , Antifungal Agents/therapeutic use , Azoles/pharmacology , Azoles/therapeutic use , Candidemia/drug therapy , Candidemia/mortality , Child , Child, Preschool , Drug Resistance, Fungal , Fluconazole/pharmacology , Fluconazole/therapeutic use , Humans , Infant , Iran/epidemiology , Male , Microbial Sensitivity Tests , Middle Aged , Prospective Studies , Saccharomycetales/drug effects , Saccharomycetales/isolation & purification , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Treatment Failure
9.
BMC Infect Dis ; 21(1): 224, 2021 Feb 27.
Article in English | MEDLINE | ID: mdl-33639846

ABSTRACT

BACKGROUND: The clinical profiles and outcomes of cryptococcal meningitis have been shown to vary depending on the underlying condition. The aim of this study was to investigate clinical characteristics and outcomes in patients with and without type II diabetes mellitus. METHODS: A retrospective study was performed. Clinical data of HIV-negative cryptococcal meningitis patients with type II diabetes mellitus (n = 26) and without type II diabetes mellitus (n = 52) referring to the Jiangxi Chest Hospital between January 2012 to December 2018 were analyzed. The data were analyzed using chi square, none-parametric tests, and logistic regression. P-values < 0.05 were considered significant. RESULTS: In this study, cryptococcal meningitis patients suffering from type II diabetes mellitus had a higher mortality (23.08% vs. 7.69%; P = 0.055), and required longer hospitalization (59.58 vs. 42.88 days; P = 0.132). Moreover, cerebrospinal fluid examinations revealed that cryptococcal meningitis patients with type II diabetes mellitus had higher opening pressure (271.54 vs. 234.23 mmH2O; P = 0.125).The results of multivariate regression analysis revealed that cryptococcal meningitis patients with type II diabetes were more often presented with visual disorders (28.54% vs. 11.54%; [95% CI 0.056-0.705]; p = 0.012), and had higher cerebrospinal fluid protein levels (1027.62 ± 594.16 vs. 705.72 ± 373.88 mg/l; [95% CI 1.000-1.002]; p = 0.016). Among patients with type II diabetes mellitus, nausea and vomiting was more frequent at the initial visit in those died (100% vs. 50%; p = 0.027), and 66% of died type II diabetes mellitus patients were poorly controlled blood glucose level, compared with 30% in survival type II diabetes mellitus patients. CONCLUSION: This study suggests that cryptococcal meningitis patients with type II diabetes mellitus differ significantly from cryptococcal meningitis patients without type II diabetes mellitus with respect to clinical symptoms such as visual disorders and cerebrospinal fluid examination. The presence of nausea and vomiting among type II diabetes mellitus patients could have implication in mortality.


Subject(s)
Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/epidemiology , Meningitis, Cryptococcal/diagnosis , Meningitis, Cryptococcal/epidemiology , Adult , Aged , China/epidemiology , Comorbidity , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/therapy , Female , HIV Seronegativity/physiology , Humans , Length of Stay/statistics & numerical data , Male , Meningitis, Cryptococcal/complications , Meningitis, Cryptococcal/therapy , Middle Aged , Mortality , Prognosis , Retrospective Studies
10.
Mycoses ; 64(4): 385-393, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33295089

ABSTRACT

Dermatophytosis is a common superficial mycotic infection affecting individual's quality of life worldwide. The present study aimed to perform species-level identification and evaluate the antifungal susceptibility patterns of dermatophytes isolated in Shiraz, Iran. This cross-sectional study was conducted on clinical samples collected during 2017-2019 from 307 patients suspected of having dermatophytosis. The isolates were identified by direct microscopy, culture and internal transcribed spacer ribosomal DNA sequencing, and their antifungal susceptibility patterns were determined by the microdilution method. Among 307 patients, dermatophytosis was diagnosed by microscopy in 190 (61.8%) subjects and confirmed in 130 (42.3%) cases by both microscopy and culture. It was found out tinea pedis was the most common clinical manifestation, and Trichophyton mentagrophytes was the most prevalent species (28.4%), followed by T tonsurans (23.8%), Microsporum canis (11.5%), T interdigitale (10%), T verrucosum (6.9%), T rubrum (6.9%), T benhamiae (4.6%), T violaceum (3%), T simii (3%), Epidermophyton floccosum (0.7%) and M ferrugineum (0.7%). Moreover, it was revealed that luliconazole with a geometric mean (GM) minimum inhibitory concentration (MIC) of 0.03 µg ml-1 was the most effective agent against all tested isolates. Regardless of species, 30% of isolates responded to high MICs of griseofulvin (MIC90  > 2 µg ml-1 ). The increasing prevalence of nonindigenous species of T simii, T benhamiae and M ferrugineum in Shiraz, Iran, was a notable finding. In addition, infections due to zoophilic species showed an increasing trend. These epidemiological data, along with antifungal susceptibility patterns, may have implications for clinical decision-making and successful treatment.


Subject(s)
Antifungal Agents/pharmacology , Arthrodermataceae/drug effects , Arthrodermataceae/genetics , Dermatomycoses/microbiology , Adolescent , Adult , Antifungal Agents/therapeutic use , Arthrodermataceae/classification , Arthrodermataceae/isolation & purification , Child , Child, Preschool , Cross-Sectional Studies , DNA, Ribosomal Spacer/genetics , Dermatomycoses/drug therapy , Dermatomycoses/epidemiology , Female , Humans , Infant , Iran/epidemiology , Male , Microbial Sensitivity Tests , Middle Aged , Quality of Life , Young Adult
11.
Antimicrob Agents Chemother ; 64(10)2020 09 21.
Article in English | MEDLINE | ID: mdl-32690638

ABSTRACT

Clonal outbreaks of fluconazole-resistant (FLZR) Candida parapsilosis isolates have been reported in several countries. Despite its being the second leading cause of candidemia, the azole resistance mechanisms and the clonal expansion of FLZR C. parapsilosis blood isolates have not been reported in Turkey. In this study, we consecutively collected C. parapsilosis blood isolates (n = 225) from the fifth largest hospital in Turkey (2007 to 2019), assessed their azole susceptibility pattern using CLSI M27-A3/S4, and sequenced ERG11 for all and MRR1, TAC1, and UPC2 for a selected number of C. parapsilosis isolates. The typing resolution of two widely used techniques, amplified fragment length polymorphism typing (AFLP) and microsatellite typing (MST), and the biofilm production of FLZR isolates with and without Y132F were compared. Approximately 27% of isolates were FLZR (60/225), among which 90% (54/60) harbored known mutations in Erg11, including Y132F (24/60) and Y132F+K143R (19/60). Several mutations specific to FLZR isolates were found in MRR1, TAC1, and UPC2 AFLP grouped isolates into two clusters, while MST revealed several clusters. The majority of Y132F/Y132F+K143R isolates grouped in clonal clusters, which significantly expanded throughout 2007 to 2019 in neonatal wards. Candida parapsilosis isolates carrying Y132F were associated with significantly higher mortality and less biofilm production than other FLZR isolates. Collectively, we documented the first outbreak of FLZR C. parapsilosis blood isolates in Turkey. The MRR1, TAC1, and UPC2 mutations exclusively found in FLZR isolates establishes a basis for future studies, which will potentially broaden our knowledge of FLZR mechanisms in C. parapsilosis MST should be a preferred method for clonal analysis of C. parapsilosis isolates in outbreak scenarios.


Subject(s)
Candidemia , Fluconazole , Amplified Fragment Length Polymorphism Analysis , Antifungal Agents/pharmacology , Candida parapsilosis/genetics , Candidemia/drug therapy , Candidemia/epidemiology , Disease Outbreaks , Drug Resistance, Fungal/genetics , Fluconazole/pharmacology , Humans , Infant, Newborn , Microbial Sensitivity Tests , Turkey
12.
Med Mycol ; 2020 Dec 10.
Article in English | MEDLINE | ID: mdl-33305331

ABSTRACT

Candiduria is common among patients admitted to intensive care units (ICUs); however, clinical and microbiological data are limited, which accounts for non-compliance with international guidelines, including over treatment of asymptomatic candiduria that promotes antifungal resistance. This prospective study included adult patients admitted to ICUs of five referral hospitals in Shiraz, Iran, during 2016-2018. Species were identified by MALDI-TOF MS, and antifungal susceptibility was assessed according to CLSI M27-A3/S4. Among 2086 patients, 162 and 293 developed candiduria and bacteriuria, respectively. In total, 174 yeast isolates were collected; 88.5% were Candida albicans (91/174; 52.2%), C. glabrata (38/174; 21.8%), and C. tropicalis (25/174; 14.3%). Antifungal resistance was rare; only two isolates (one C. tropicalis and one C. krusei) were fluconazole resistant. Symptomatic candiduria was noted in 31.4% of patients (51/162); only 37% (19/51) of them were treated and 36.82% (7/19) showed fluconazole therapeutic failure. Two symptomatic patients developed candidemia shortly after candiduria. Among asymptomatic patients, 31.5% (35/111) were overtreated with fluconazole. The mortality rate was 25.3% (41/162); it did not differ between symptomatic and asymptomatic patients. Our results indicate that deviation from standard-of-care treatment for candiduria is a matter of concern given the high rate of fluconazole therapeutic failure among patients with symptomatic candiduria. LAY SUMMARY: Candiduria is an underestimated clinical presentation among critically ill patients and detailed data are scarce in this regard. Given the high rate of fluconazole therapeutic failure and development of candidemia in some cases, the mistreatment of candiduria should not be overlooked by clinicians.

13.
Med Mycol ; 58(6): 766-773, 2020 Aug 01.
Article in English | MEDLINE | ID: mdl-31828316

ABSTRACT

Candida tropicalis is one of the major candidaemia agents, associated with the highest mortality rates among Candida species, and developing resistance to azoles. Little is known about the molecular mechanisms of azole resistance, genotypic diversity, and the clinical background of C. tropicalis infections. Consequently, this study was designed to address those questions. Sixty-four C. tropicalis bloodstream isolates from 62 patients from three cities in Iran (2014-2019) were analyzed. Strain identification, antifungal susceptibility testing, and genotypic diversity analysis were performed by MALDI-TOF MS, CLSI-M27 A3/S4 protocol, and amplified fragment length polymorphism (AFLP) fingerprinting, respectively. Genes related to drug resistance (ERG11, MRR1, TAC1, UPC2, and FKS1 hotspot9s) were sequenced. The overall mortality rate was 59.6% (37/62). Strains were resistant to micafungin [minimum inhibitory concentration (MIC) ≥1 µg/ml, 2/64], itraconazole (MIC > 0.5 µg/ml, 2/64), fluconazole (FLZ; MIC ≥ 8 µg/ml, 4/64), and voriconazole (MIC ≥ 1 µg/ml, 7/64). Pan-azole and FLZ + VRZ resistance were observed in one and two isolates, respectively, while none of the patients were exposed to azoles. MRR1 (T255P, 647S), TAC1 (N164I, R47Q), and UPC2 (T241A, Q340H, T381S) mutations were exclusively identified in FLZ-resistant isolates. AFLP fingerprinting revealed five major and seven minor genotypes; genotype G4 was predominant in all centers. The increasing number of FLZ-R C. tropicalis blood isolates and acquiring FLZ-R in FLZ-naive patients limit the efficiency of FLZ, especially in developing countries. The high mortality rate warrants reaching a consensus regarding the nosocomial mode of C. tropicalis transmission.


Subject(s)
Antifungal Agents/pharmacology , Candida tropicalis/drug effects , Candida tropicalis/genetics , Drug Resistance, Fungal/genetics , Adolescent , Adult , Aged , Aged, 80 and over , Amplified Fragment Length Polymorphism Analysis , Candidemia/microbiology , Candidemia/mortality , Child , Child, Preschool , Female , Genetic Variation , Genotype , Genotyping Techniques , Humans , Infant , Iran/epidemiology , Male , Microbial Sensitivity Tests , Middle Aged , Mutation , Retrospective Studies , Young Adult
14.
Mycoses ; 63(9): 911-920, 2020 Sep.
Article in English | MEDLINE | ID: mdl-32413170

ABSTRACT

BACKGROUND: Candida glabrata is the third leading cause of candidaemia in Turkey; however, the data regarding antifungal resistance mechanisms and genotypic diversity in association with their clinical implication are limited. OBJECTIVES: To assess genotypic diversity, antifungal susceptibility and mechanisms of drug resistance of C glabrata blood isolates and their association with patients' outcome in a retrospective multicentre study. PATIENTS/METHODS: Isolates from 107 patients were identified by ITS sequencing and analysed by multilocus microsatellite typing, antifungal susceptibility testing, and sequencing of PDR1 and FKS1/2 hotspots (HSs). RESULTS: Candida glabrata prevalence in Ege University Hospital was twofold higher in 2014-2019 than in 2005-2014. Six of the analysed isolates had fluconazole MICs ≥ 32 µg/mL; of them, five harboured unique PDR1 mutations. Although echinocandin resistance was not detected, three isolates had mutations in HS1-Fks1 (S629T, n = 1) and HS1-Fks2 (S663P, n = 2); one of the latter was also fluconazole-resistant. All patients infected with isolates carrying HS-FKS mutations and/or demonstrating fluconazole MIC ≥ 32 µg/mL (except one without clinical data) showed therapeutic failure (TF) with echinocandin and fluconazole; seven such isolates were collected in Ege (n = 4) and Gulhane (n = 3) hospitals and six detected recently. Among 34 identified genotypes, none were associated with mortality or enriched for fluconazole-resistant isolates. CONCLUSION: Antifungal susceptibility testing should be supplemented with HS-FKS sequencing to predict TF for echinocandins, whereas fluconazole MIC ≥ 32 µg/mL may predict TF. Recent emergence of C glabrata isolates associated with antifungal TF warrants future comprehensive prospective studies in Turkey.


Subject(s)
Antifungal Agents/pharmacology , Candida glabrata/drug effects , Candida glabrata/genetics , Drug Resistance, Fungal/genetics , Fluconazole/pharmacology , Adolescent , Aged , Antifungal Agents/therapeutic use , Candidemia/microbiology , Female , Fluconazole/therapeutic use , Fungal Proteins/genetics , Genetic Variation , Genotype , Humans , Male , Middle Aged , Mutation , Retrospective Studies , Treatment Failure , Turkey , Young Adult
15.
Mycopathologia ; 185(6): 959-969, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32789738

ABSTRACT

Cryptococcal meningitis (CM) is a rare complication in HIV-negative patients with nephrotic syndrome (NS), and knowledge about the clinical profile of NS with CM is limited. We performed a retrospective study of all patients with CM-NS admitted to the Jiangxi Chest Hospital (JCH) between 2011 and 2019 and systematically reviewed cases of CM-NS reported in the Chinese language. Among a total of 226 CM patients referred to the JCH, seven had NS (3.1%); these patients were combined with 22 CM-NS cases reported in the Chinese language for analysis. Headache, fever, nausea, and meningeal irritation were the most common initial symptoms, and the median time from symptom onset to CM diagnostic confirmation was 30 days. One patient initially tested negative for CM but was later confirmed to be positive. Among the 29 analysed patients, 41.4% (12/29) were misdiagnosed with other complications, including four patients from the JCH (4/7, 57.1%) and eight patients from published reports (8/22, 36.3%). The overall mortality rate was 17.2% (5/29); among these patients, 60% (3/5) were misdiagnosed. Induction treatment with amphotericin B plus 5-fluorocytosine (9/29) or amphotericin B plus fluconazole (7/29) successfully cleared the infection. Fluconazole may be a suitable alternative if 5-fluorocytosine is not readily available or not tolerated, and repetitive testing is important to reach a conclusive diagnosis in NS patients suspected of having CM.


Subject(s)
HIV Infections , Meningitis, Cryptococcal , Nephrotic Syndrome , Antifungal Agents/therapeutic use , China , Fluconazole/therapeutic use , HIV Infections/complications , Hospitals, Teaching , Humans , Meningitis, Cryptococcal/complications , Meningitis, Cryptococcal/drug therapy , Nephrotic Syndrome/complications , Retrospective Studies
16.
Article in English | MEDLINE | ID: mdl-31285227

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).


Subject(s)
Anidulafungin/pharmacology , Antifungal Agents/pharmacology , Candida glabrata/drug effects , Candida glabrata/genetics , Drug Resistance, Fungal/genetics , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/standards , Blood Culture , Candida glabrata/growth & development , Candida glabrata/isolation & purification , Candidiasis/drug therapy , Candidiasis/microbiology , Caspofungin/pharmacology , Fungal Proteins/genetics , Gene Expression , Glucosyltransferases/genetics , Humans , Microbial Sensitivity Tests/methods , Microbial Sensitivity Tests/standards , Sensitivity and Specificity , Sequence Analysis, DNA , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods
17.
Article in English | MEDLINE | ID: mdl-30936110

ABSTRACT

Establishing an effective empirical antifungal therapy requires that national surveillance studies be conducted. Herein, we report the clinical outcome of infections with and the microbiological features of Iranian isolates of Candidaglabrata derived from patients suffering from candidemia. C. glabrata isolates were retrospectively collected from four major cities in Iran; identified by a 21-plex PCR, matrix-assisted laser desorption ionization-time of flight mass spectrometry, and large subunit of ribosomal DNA sequencing; and genotyped by amplified fragment length polymorphism (AFLP). Mutations in PDR1, ERG11, and hot spot 1 (HS1) of FKS1 and FKS2 were investigated, and antifungal susceptibility testing (AFST) was performed (by the CLSI M27-A3 and M27-S4 methods). Seventy isolates of C. glabrata were collected from 65 patients with a median age of 58 years. Fluconazole was the most widely used (29.23%) and least effective antifungal agent. The overall crude mortality rate was 35.4%. Only one strain was resistant to fluconazole, and 57.7% and 37.5% of the isolates were non-wild type (non-WT) for susceptibility to caspofungin and voriconazole, respectively. All isolates showed the WT phenotype for amphotericin B, posaconazole, and itraconazole. HS1 of FKS1 and FKS2 did not harbor any mutations, while numerous missense mutations were observed in PDR1 and ERG11 AFLP clustered our isolates into nine genotypes; among them, genotypes 1 and 2 were significantly associated with a higher mortality rate (P = 0.034 and P = 0.022, α < 0.05). Moreover, 83.3% of patients infected with strains harboring a single new mutation in PDR1, T745A, died despite treatment with fluconazole or caspofungin. Overall, Iranian isolates of C. glabrata were susceptible to the major antifungal drugs. Application of genotyping techniques and sequencing of a specific gene (PDR1) might have prognostic implications.


Subject(s)
Antifungal Agents/pharmacology , Candida glabrata/drug effects , Candida glabrata/genetics , Amplified Fragment Length Polymorphism Analysis/methods , Drug Resistance, Fungal/genetics , Female , Genotype , Humans , Iran , Male , Microbial Sensitivity Tests/methods , Middle Aged , Prognosis , Retrospective Studies
18.
Med Mycol ; 57(7): 833-840, 2019 10 01.
Article in English | MEDLINE | ID: mdl-30649481

ABSTRACT

Although Cyberlindnera fabinaii is a rare opportunist yeast species, its ability to cause septicemia, produce biofilm, and rapid acquisition of resistance to fluconazole and voriconazole, reinforced the urge for its identification from its closely related species. Widely used biochemical assays mainly identify Cyberlindnera fabinaii as Cyberlindnera jadinii and Wickerhamomyces anomalus, resulting in underestimation of this yeast in clinical settings. Moreover, the urge for a reliable molecular means of identification remains unsolved for 28 years. In order to unequivocally differentiate Cy. fabianii, Cy. mississipiensis, Cy. jadinii, and W. anomalus, we designed a dual-function multiplex polymerase chain reaction (PCR) assay. Challenging our dual-function multiplex PCR assay with 30 most clinically important yeast species, proved its specificity. Although conventional PCR could differentiate four target species, the real-time PCR counterpart due to Tm overlap misidentified Cy. mississipiensis as Cy. jadinii. Alongside of presenting a comprehensive literature review of published cases of Cy. fabianii from 1990 to 2018, we collected various clinical isolates from Tehran, Shiraz, and Fasa (July 1, 2017, to December 31, 2017) to find a passive relative distribution of these closely-related species in Iran. Subjecting our Iranian collection of yeast isolates to matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS and LSU and ITS rDNA sequencing revealed six isolates of Cy. fabianii (central venous catheter n = 2 and vaginal swabs n = 4) and one isolate of Cy. jadinii (vaginal swabs). Due to the use of biochemical assays in global ARTEMIS study, we encourage reidentification of clinical isolates of Cy. jadinii and Cy. jadinii using MALDI-TOF or Sanger sequencing that might lead to correcting the distribution of this fungus.


Subject(s)
Mycoses/microbiology , Saccharomycetales/classification , Saccharomycetales/isolation & purification , Antifungal Agents/pharmacology , DNA Primers/genetics , DNA, Ribosomal/genetics , Female , Humans , Iran , Male , Multiplex Polymerase Chain Reaction , Sensitivity and Specificity , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization , Vagina/microbiology
19.
BMC Infect Dis ; 18(1): 480, 2018 Sep 25.
Article in English | MEDLINE | ID: mdl-30253748

ABSTRACT

BACKGROUND: Candida albicans, Candida glabrata, and Candida parapsilosis are three prevalent causes of candidiasis, worldwide. These species are considered as nine medically important complex species. Limited knowledge about these newly recognized species prompted us to develop a one-step, multiplex PCR to detect and identify them in clinical settings. METHODS: Primers targeting Hyphal Wall Protein I gene for the C. albicans, C. dubliniensis, C. africana, Intergenic Spacer for the C. glabrata, C. nivariensis, C. bracarensis, and Intein and ITS rDNA for the C. parapsilosis, C. orthopsilosis, and C. metapsilosis were designed. Using 168 CBS reference strains and 280 clinical isolates, the specificity and reproducibility of the developed assay were evaluated. RESULTS: Our developed assay successfully identified and distinguished all the nine species. No cross-reaction with closely- and distantly-related yeast species, Aspergillus species and human DNA was observed, resulting in 100% specificity. The ambiguous results obtained by MALDI-TOF for C. albicans and C. africana were corrected by our 9-plex PCR assay. This assay identified all the cryptic complex species from two test sets from Iran and China, correctly. CONCLUSIONS: Our developed multiplex assay is accurate, specific, cost/time-saving, and works without the tedious DNA extraction steps. It could be integrated into routine clinical laboratories and as a reliable identification tool and has the potential to be implemented into epidemiological studies to broaden the limited knowledge of cryptic species complexes.


Subject(s)
Candida albicans/genetics , Candida glabrata/genetics , Candida parapsilosis/genetics , DNA, Ribosomal/analysis , Multiplex Polymerase Chain Reaction , Candida albicans/isolation & purification , Candida glabrata/isolation & purification , Candida parapsilosis/isolation & purification , Candidiasis/diagnosis , Candidiasis/microbiology , DNA, Fungal/isolation & purification , DNA, Fungal/metabolism , DNA, Ribosomal/metabolism , Humans , Reproducibility of Results , Sequence Analysis, DNA , Species Specificity , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
20.
Mycoses ; 61(2): 134-142, 2018 Feb.
Article in English | MEDLINE | ID: mdl-29064123

ABSTRACT

Aspergillus terreus infections are difficult to treat because of the intrinsic resistance to amphotericin B, and higher mortality compared to infections caused by other Aspergillus species. The aim of the present study was to determine the in vitro antifungal activity of amphotericin B and 11 comparators against clinical (n = 36) and environmental (n = 45) A. terreus isolates. In vitro antifungal susceptibility was performed using the CLSI M38-A2 procedure. Amphotericin B exhibited the highest MICs (MIC range, 0.125-4 µg/mL; MIC90 , 2 µg/mL), followed by terbinafine (MIC range, 0.002-1 µg/mL; MIC90 , 1 µg/mL). Only one isolate (1/81) showed amphotericin B MIC above the epidemiologic cut-off value (ECV; 4 µg/mL). None of the isolates had a MIC of ≥ ECV for voriconazole, itraconazole and posaconazole. The reasons for the difference in amphotericin B susceptibility patterns between studies remain unknown. The genetic and species diversity, clinical, environmental and ecological factors in Terrei section on various amphotericin B susceptibility profiles in different countries should be considered more as the main reasons associated with these differences.


Subject(s)
Amphotericin B/pharmacology , Antifungal Agents/pharmacology , Aspergillus/drug effects , Adolescent , Adult , Aspergillosis/microbiology , Aspergillus/isolation & purification , Environmental Microbiology , Female , Humans , Male , Microbial Sensitivity Tests , Middle Aged , Young Adult
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