Melike Yaşar Duman

Dr. Melike Yaşar Duman

orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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21 September 2020 in Antimicrobial Agents and Chemotherapy
Verified
Journal Article
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AAAmir Arastehfar
Amir Arastehfar
FDFarnaz Daneshnia
Farnaz Daneshnia
SPSüleyha - Polat
Süleyha - Polat
WFWenjie Fang
Wenjie Fang
MDMelike Yaşar Duman
Melike Yaşar Duman
TBTeunis Boekhout
Teunis Boekhout
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.

11 November 2020 in Journal of Antimicrobial Chemotherapy
Verified
Journal Article
Closed access
AAAmir Arastehfar
Amir Arastehfar
FDFarnaz Daneshnia
Farnaz Daneshnia
SHSüleyha Hilmioglu-Polat
Süleyha Hilmioglu-Polat
Macit IlkitMacit Ilkit
Macit Ilkit
MDMelike Yaşar Duman
Melike Yaşar Duman
CLCornelia Lass-Flörl
Cornelia Lass-Flörl
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.

15 May 2020 in Mycoses
Verified
Journal Article
Open access
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AAAmir Arastehfar
Amir Arastehfar
FDFarnaz Daneshnia
Farnaz Daneshnia
MSMohammadreza Salehi
Mohammadreza Salehi
MDMelike Yaşar Duman
Melike Yaşar Duman
THTugrul Hosbul
Tugrul Hosbul
CLCornelia Lass-Flörl
Cornelia Lass-Flörl
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.

5 August 2021 in Annals of Clinical Microbiology and Antimicrobials
Verified
Journal Article
Open access
PDF file
MKMustafa Karataş
Mustafa Karataş
MDMelike Yaşar Duman
Melike Yaşar Duman
ATAlper Tünger
Alper Tünger
FÇFeriha Çilli
Feriha Çilli
ŞAŞöhret Aydemir
Şöhret Aydemir
VÖVolkan Özenci
Volkan Özenci
Purpose: In this study, we aimed to evaluate the epidemiology and antimicrobial resistance (AMR) patterns of bacterial pathogens in COVID-19 patients and to compare the results with control groups from the pre-pandemic and pandemic era.Methods: Microbiological database records of all the COVID-19 diagnosed patients in the Ege University Hospital between March 15, 2020, and June 15, 2020, evaluated retrospectively. Patients who acquired secondary bacterial infections (SBIs) and bacterial co-infections were analyzed. Etiology and AMR data of the bacterial infections were collected. Results were also compared to control groups from pre-pandemic and pandemic era data.Results: In total, 4859 positive culture results from 3532 patients were analyzed. Fifty-two (3.59%) patients had 78 SBIs and 38 (2.62%) patients had 45 bacterial co-infections among 1447 COVID-19 patients. 22/85 (25.88%) patients died who had bacterial infections. The respiratory culture-positive sample rate was 39.02% among all culture-positive samples in the COVID-19 group. There was a significant decrease in extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales (8.94%) compared to samples from the pre-pandemic (20.76%) and pandemic era (20.74%) (p = 0.001 for both comparisons). Interestingly, Acinetobacter baumannii was the main pathogen in the respiratory infections of COVID-19 patients (9.76%) and the rate was significantly higher than pre-pandemic (3.49%, p < 0.002) and pandemic era control groups (3.11%, p < 0.001).Conclusion: Due to the low frequency of SBIs reported during the ongoing pandemic, a more careful and targeted antimicrobial prescription should be taken. While patients with COVID-19 had lower levels of ESBL-producing Enterobacterales, the frequency of multidrug-resistant (MDR) A. baumannii is higher.

10 July 2017 in Mikrobiyoloji Bulteni
Verified
Journal Article
Closed access
YTYamaç Tekintaş
Yamaç Tekintaş
FÇFeriha Çi̇lli̇
Feriha Çi̇lli̇
BEBayrı ERAÇ
Bayrı ERAÇ
MDMelike Yaşar Duman
Melike Yaşar Duman
SASabire Şöhret Aydemi̇r
Sabire Şöhret Aydemi̇r
MLMine Hoşgör Li̇moncu
Mine Hoşgör Li̇moncu
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28 November 2022 in Turkish Journal of Parasitology
Verified
Journal Article
Closed access
ETEnis Fuat Tufekci
Enis Fuat Tufekci
MDMelike Yaşar Duman
Melike Yaşar Duman
BÇBüşra Çalışır
Büşra Çalışır
ÇKÇetin Kılınç
Çetin Kılınç
AUAhmet Uzel
Ahmet Uzel
Toxoplasma gondii (T. gondii) is a protozoan parasite that infects most warm-blooded animal species and causes toxoplasmosis. Especially infections that occur during pregnancy can lead to serious clinical symptoms. This study retrospectively revealed the T. gondii seroprevalence of pregnant women in Kastamonu province, Turkey. Anti-T. gondii IgM and IgG positivity of 1.294 pregnant women between the ages of 15-44 years who applied to the Obstetrics and Gynecology Outpatients of Kastamonu Training and Research Hospital from January 2018 to January 2022 were investigated retrospectively. The IgG avidity test was performed for both anti-T. gondii IgM and IgG positivity. Anti-T. gondii IgM and IgG seropositivity were determined as 1.1% (n=14) and 20.3% (n=263), respectively. Anti-T. gondii IgM and IgG positivity were detected together in 11 pregnant women. IgG avidity test results of only six pregnant women could be reached, two pregnant had high IgG avidity, and four pregnant had low IgG avidity. Anti-T. gondii IgG positivity rate increased with increasing age (p=0.039). The number of seronegative pregnant women was considered high in Kastamonu. It is significant for expectant mothers to know about prevention methods in order not to acquire toxoplasmosis.