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1.
Indian J Med Microbiol ; 49: 100594, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38636843

ABSTRACT

PURPOSE: Candida auris is increasingly being isolated from patients all over the world. It has five clades. In this study, it was aimed to compare the results of biochemical tests obtained using different methods and the antifungal susceptibility profiles of C. auris strains isolated from the first seven cases reported in Türkiye, and evaluate whether this information could be useful as preliminary data in determining the clade of strains in centers that lack the opportunity to apply molecular methods. METHODS: Identification test results obtained using API ID 32 C, API 20 C AUX, VITEK-2 YST, and MALDI-TOF MS; colony color and morphology on Chromagar Candida, CHROMagar Candida Plus media, and cornmeal-Tween 80 agar; susceptibility to antifungals were tested and compared. Antifungal susceptibility test was studied using microdilution method according to the recommendations of EUCAST. Additionally, a pilot study was conducted to investigate the value of CHROMagar Candida Plus. RESULTS: All seven strains were identified as Lachancea kluyveri with API ID 32 C, Rhodotorula glutinis; Cryptococcus neoformans with API 20 C AUX, and C. auris with both VITEK-2 YST and MALDI-TOF MS. MIC values for fluconazole were very high (≥64 mg/L) for all seven strains. It was observed that 11 (37.9%) of 29 Candida parapsilosis strains formed colonies with morphology similar to C. auris on CHROMagar Candida Plus medium, leading to false positivity. CONCLUSIONS: Although there have been many isolations of C. auris in our country in recent years, clade distribution of only a small number of strains is known yet. In this study, when the biochemical properties and antifungal susceptibility profiles of the seven strains were evaluated, it was concluded that they exhibited some characteristics compatible with clade I. It was also observed that strains 1 and 2 may belong to a different clade.

2.
Med Mycol ; 62(5)2024 May 03.
Article in English | MEDLINE | ID: mdl-38592959

ABSTRACT

Candida species are the primary cause of fungal infections in intensive care units (ICUs). Despite the increasing prevalence of Candida-related infections, monitoring the progression of these infections from colonization in COVID-19 ICU patients lacks sufficient information. This study aims prospectively to compare 62 COVID-19 and 60 non-COVID-19 ICU patients from admission to discharge in terms of colonization development, rates, isolated Candida species, risk factors, and Candida infections during hospitalization. A total of 1464 samples were collected at specific time intervals from various body sites [mouth, skin (axilla), rectal, and urine]. All samples were inoculated onto CHROMagar Candida and CHROMagar Candida Plus media, and isolates identified using MALDI-TOF MS. COVID-19 patients exhibited significantly higher colonization rates in oral, rectal, and urine samples compared to non-COVID-19 patients, (p < 0.05). Among the Candida species, non-albicans Candida was more frequently detected in COVID-19 patients, particularly in oral (75.8%-25%; p < 0.001) and rectal regions (74.19% - 46.66%; p < 0.05). Colonization with mixed Candida species was also more prevalent in the oropharyngeal region (p < 0.05). Mechanical ventilation and corticosteroid use emerged as elevated risk factors among COVID-19 patients (p < 0.05). Despite the colonization prevalence, both COVID-19-positive and negative patients exhibited low incidences of Candida infections, with rates of 9.67% (n = 6/62) and 6.67% (n = 3/60), respectively. Consequently, although Candida colonization rates were higher in COVID-19 ICU patients, there was no significant difference in Candida infection development compared to the non-COVID-19 group. However, the elevated rate of non-albicans Candida isolates highlights potential future infections, particularly given their intrinsic resistance in prophylactic or empirical treatments if needed. Additionally, the high rate of mixed colonization emphasizes the importance of using chromogenic media for routine evaluation.


This is the first prospective cohort study comparing Candida colonization features including species and body sites from the time of admission to the externalization in intensive care unit patients with and without COVID-19. It provides key points that can be referenced for fungal approaches in future disasters.


Subject(s)
COVID-19 , Candida , Candidiasis , Intensive Care Units , Humans , Intensive Care Units/statistics & numerical data , COVID-19/microbiology , COVID-19/epidemiology , Male , Prospective Studies , Female , Middle Aged , Candida/isolation & purification , Candida/classification , Aged , Candidiasis/epidemiology , Candidiasis/microbiology , Turkey/epidemiology , Adult , Risk Factors , SARS-CoV-2/isolation & purification , Prevalence , Mouth/microbiology , Mouth/virology
3.
Pathogens ; 12(10)2023 Oct 09.
Article in English | MEDLINE | ID: mdl-37887742

ABSTRACT

Among sexually transmitted diseases, HIV causes very serious clinical manifestations that can lead to death. As a result, millions of people have to live with this problem that threatens their health. The virus attacks the immune system of the host, especially CD4+ T lymphocytes, causing the suppression of the immune system. CD4, CD8 counts, and HIV RNA viral loads are monitored in HIV-infected patients with antiretroviral treatment, and CD4 counts play an important role in determining the effectiveness of the treatment. Despite the advances in treatment in the present day, opportunistic infections are the main cause of morbidity and mortality in these patients, and the evaluation of immunological parameters is valuable for the prognosis of the disease in this process. In the present study, the purpose was to investigate the opportunistic infections faced by naive HIV-positive patients who applied to our laboratory and were diagnosed between 2019 and 2022 during their one-year treatment period, and the correlation of the immunological parameters was also evaluated retrospectively using the hospital automation system and laboratory data. A total of 107 opportunistic causative microorganisms were identified in 87 of the 230 HIV-positive patients over one year. T. pallidum was detected in 43 (18.6%) of these patients, Cytomegalovirus (CMV) in 32 (13.9%), Epstein-Barr virus (EBV) in 9 (3.9%), Hepatitis B virus (HBV) in 10 (4.3%), C. albicans in 7 (3%), M. tuberculosis in 3 (1.3%), Hepatitis C virus (HCV) in 2 (0.8%), and C. glabrata in 1 (0.4%) patient. Although mono-agent co-infections were determined in 69 of 87 people living with HIV, two-agent co-infections were detected in 16 HIV patients, and three-agent co-infections were identified in two HIV patients. Considering the correlation between the CD4/CD8 ratio and infection positivity, a moderate negative correlation was determined with HIV RNA viral load and CMV infection. The CD4/CD8 ratio had a low negative correlation with EBV and C. albicans infections. It was also found that the follow-up of HIV RNA load in the diagnosis of T. pallidum, CMV, EBV, and C. albicans may be meaningful. Opportunistic infections mainly affect immunosuppressed patients and can be prevented with effective treatment. Although it is already known that HIV patients may face different infections during their treatment, it was concluded that more attention should be paid to T. pallidum, CMV, EBV, and C. albicans agents. These infections should be routinely monitored with HIV viral load and the CD4/CD8 ratio.

4.
J Fungi (Basel) ; 9(10)2023 Oct 19.
Article in English | MEDLINE | ID: mdl-37888282

ABSTRACT

Candida auris has emerged as a significant fungal threat due to its rapid worldwide spread since its first appearance, along with its potential for antimicrobial resistance and virulence properties. This study was designed to examine virulence characteristics, the efficacy of ceragenins, and biofilm-derived drug resistance in seven C. auris strains isolated from Turkish intensive care patients. It was observed that none of the tested strains exhibited proteinase or hemolysis activity; however, they demonstrated weak phospholipase and esterase activity. In addition, all strains were identified as having moderate to strong biofilm formation characteristics. Upon determining the minimum inhibitory concentrations (MIC) of ceragenins, it was discovered that CSA-138 exhibited the highest effectiveness with a MIC range of 1-0.5 µg/mL, followed by CSA-131 with a MIC of 1 µg/mL. Also, antimicrobial agents destroyed mature biofilms at high concentrations (40-1280 µg/mL). The investigation revealed that the strains isolated from Türkiye displayed weak exoenzyme activities. Notably, the ceragenins exhibited effectiveness against these strains, suggesting their potential as a viable treatment option.

5.
Healthcare (Basel) ; 11(18)2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37761778

ABSTRACT

Bacteremia and fungemia are significant causes of morbidity and mortality that frequently occur as co-infections with viral respiratory infections, including SARS-CoV-2. The aim of this study was to evaluate the microorganisms that were isolated from the blood cultures of SARS-CoV-2-positive and negative patients and investigate their antimicrobial resistance patterns. A retrospective analysis was performed of 22,944 blood cultures sent to the laboratory between November 2020 and December 2021. Blood culture analyses were performed using the BD Bactec FX automated system. Identification was carried out using conventional methods, namely, VITEK-2 and MALDI-TOF MS. Antibacterial/antifungal susceptibility tests were performed according to EUCAST/CLSI recommendations. SARS-CoV-2 tests were performed with RT-PCR. Culture positivity was detected in 1630 samples from 652 patients. Of these 652 patients, 633 were tested for SARS-CoV-2; 118 (18.6%) were positive and 515 (81.3%) were negative. The bacteria and fungi that were isolated at the highest rate in SARS-CoV-2-positive patients were methicillin-resistant coagulase-negative staphylococci (MR-CoNS) (21.5%), Escherichia coli (12.4%), Klebsiella pneumoniae (12.4%), Candida albicans (1.65%), and Candida glabrata complex (1.65%), while in the negative patients, the highest rates were for E. coli (21.3%), MR-CoNS (13.5%), K. pneumoniae (12.05%), C. albicans (2.1%), Candida parapsilosis (1.1%), and Candida tropicalis (0.9%). No statistically significant difference was determined between COVID-19-positive and negative patients in terms of detection, such as with the Pseudomonas spp., Enterococcus spp., and methicillin-resistant Staphylococcus aureus isolated from the blood cultures (p > 0.05). The most common isolate was MR-CoNS in SARS-CoV-2-positive patients (p = 0.028). Acinetobacter baumannii was more frequent (p = 0.004) and carbapenem-resistant K. pneumoniae was isolated at a higher rate (60% vs. 43%) in SARS-CoV-2-positive patients compared to SARS-CoV-2-negative patients (p > 0.05). These findings highlight the fact that isolation procedures should not be disregarded and the distribution of bacterial/fungal agents of bloodstream infections and their antibiotic resistance should be followed up during a pandemic, such as in the case of COVID-19.

6.
Mycoses ; 66(9): 755-766, 2023 09.
Article in English | MEDLINE | ID: mdl-37165906

ABSTRACT

Rhinocladiella mackenziei is a highly neurotropic fungus, mainly reported from the Middle East. However, in recent years, there have been some cases from outside this region. We described an additional fatal case of R. mackenziei cerebral infection for the first time from Turkey and made a literature review of all previously reported cases. During 34 years (1988-2022), there have been 42 R. mackenziei brain abscess cases. Most patients have been reported from Saudi Arabia (n = 14, 33.3%). It is noteworthy that 40.5% of patients, including our case, were immunocompetent at initial diagnosis and mostly presented with a single lesion (n = 10, 23.8%). The most frequent comorbidities were solid organ transplant (n = 9, 21.4%), diabetes mellitus (n = 6, 14.3%), malignancy (n = 6, 14.3%) and prior surgery (n = 3, 7.1%). The most commonly used initial antifungal regimen were amphotericin B together with itraconazole (n = 9, 21.4%), combinations of lipid preparations of amphotericin B, voriconazole and/or posaconazole (n = 9, 21.4%) and amphotericin B alone (n = 8, 19%). Although both surgical procedures and antifungal medication in the majority of patients were performed, mortality rates remained high (90.4%). The area at risk of R. mackenziei cerebral abscess cases extends to other countries. Clinicians should be aware of this emerging disease and take a detailed travel history in patients with atypical and undocumented brain abscesses. Our case confirms the hypothesis that this fungus might spread more widely than previously predicted regions.


Subject(s)
Brain Abscess , Central Nervous System Fungal Infections , Humans , Antifungal Agents/therapeutic use , Amphotericin B/therapeutic use , Turkey , Central Nervous System Fungal Infections/diagnosis , Central Nervous System Fungal Infections/drug therapy , Central Nervous System Fungal Infections/microbiology , Brain Abscess/drug therapy , Brain Abscess/microbiology , Brain Abscess/pathology
7.
J Antimicrob Chemother ; 77(7): 1894-1898, 2022 06 29.
Article in English | MEDLINE | ID: mdl-35445259

ABSTRACT

OBJECTIVES: Aspergillus fumigatus causes several diseases in humans and azole resistance in A. fumigatus strains is an important issue. The aim of this multicentre epidemiological study was to investigate the prevalence of azole resistance in clinical and environmental A. fumigatus isolates in Turkey. METHODS: Twenty-one centres participated in this study from 1 May 2018 to 1 October 2019. One participant from each centre was asked to collect environmental and clinical A. fumigatus isolates. Azole resistance was screened for using EUCAST agar screening methodology (EUCAST E.DEF 10.1) and was confirmed by the EUCAST E.DEF 9.3 reference microdilution method. Isolates with a phenotypic resistance pattern were sequenced for the cyp51A gene and microsatellite genotyping was used to determine the genetic relationships between the resistant strains. RESULTS: In total, resistance was found in 1.3% of the strains that were isolated from environmental samples and 3.3% of the strains that were isolated from clinical samples. Mutations in the cyp51A gene were detected in 9 (47.4%) of the 19 azole-resistant isolates, all of which were found to be TR34/L98H mutations. Microsatellite genotyping clearly differentiated the strains with the TR34/L98H mutation in the cyp51A gene from the strains with no mutation in this gene. CONCLUSIONS: The rate of observed azole resistance of A. fumigatus isolates was low in this study, but the fact that more than half of the examined strains had the wild-type cyp51A gene supports the idea that other mechanisms of resistance are gradually increasing.


Subject(s)
Aspergillosis , Aspergillus fumigatus , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Aspergillosis/drug therapy , Aspergillosis/epidemiology , Azoles/pharmacology , Drug Resistance, Fungal/genetics , Fungal Proteins/genetics , Humans , Microbial Sensitivity Tests , Turkey/epidemiology
8.
Mikrobiyol Bul ; 55(4): 648-655, 2021 Oct.
Article in Turkish | MEDLINE | ID: mdl-34666664

ABSTRACT

Candida auris is a species of fungus that has gained importance in recent years owing to its ability to cause hospital infections and epidemics, resistant to antifungal agents and disinfection processes and frequently misidentified by commercial systems. Hospital outbreaks caused by C.auris have been reported from some countries. It has been determined that C.auris has lower virulence than Candida albicans; however, it is associated with high mortality rates in immunocompromised individuals. An increase in the incidence of invasive fungal infections which can lead to serious complications and death, has been identified in severe coronavirus-2019 (COVID-19) patients or immunocompromised individuals with underlying disease. Studies demonstrated an increase in the frequency of C.auris isolation in COVID-19 patients with candidemia. In this report, the first case of COVID-19 positive C.auris fungemia detected in Turkey was presented. A 71-year-old male patient with a history of myocardial infarction, diabetes mellitus, donation of a single kidney and lobectomy surgery due to lung cancer was hospitalized in the pandemic thoracic surgery service due to the findings consistent with viral pneumonia on thoracic computed tomography. Favipiravir 2 x 600 mg and intravenous dexamethasone 1 x 6 mg therapy was administered. The patient tested positive for SARS-CoV-2 polymerase chain reaction, and severe involvement of the left lung was detected in the following days. Antibiotics were administered, followed by insertion of a right jugular vein catheter and initation of tocilizumab. The patient was transferred to the intensive care unit due to increased respiratory distress. Yeast growth was detected in the patient's hemoculture. The yeast strain could not be identified using API ID 32C (bioMerieux, France) (Sacchromyces kluyveri, Candida sake, unacceptable profile), but was identified as C.auris using the VITEK MALDI TOF MS (bioMerieux, France) (99.9%) system and confirmed by sequencing. The minimum inhibitor concentration values were detected as 3 µg/ml for amphotericin B; > 256 µg/ml for fluconazole; 0.19 µg/ml for voriconazole; 0.19 µg/ml for itraconazole; 0.016 µg/ml for posaconazole; 1 µg/ml for caspofungin and 0.094 µg/ml for anidulafungin by using the antibiotic gradient method. The patient's initial treatment comprised meropenem 3 x 1 g, vancomycin 2 x 1 g, caspofungin 1 x 70 mg, and continued as caspofungine 1 x 50 mg after the loading dose, and vancomycin 1 x 1 g/48 hours from the third day of treatment. The patient died on the ninth day after developing candidemia. The present case is the first case of fungemia caused by C.auris in a COVID-19 positive patient in Turkey, and it emphasizes the need of caution for fungemia due to C.auris in intensive care units in our country which has a high COVID-19 incidence.


Subject(s)
COVID-19 , Candidemia , Fungemia , Aged , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Candida , Candidemia/diagnosis , Candidemia/drug therapy , Candidemia/epidemiology , Fungemia/drug therapy , Humans , Male , Microbial Sensitivity Tests , SARS-CoV-2 , Turkey/epidemiology
9.
J Antimicrob Chemother ; 76(2): 443-450, 2021 01 19.
Article in English | MEDLINE | ID: mdl-33094334

ABSTRACT

BACKGROUND: Stenotrophomonas maltophilia is a Gram-negative bacterium resistant to several antibiotics and its prevalence in cystic fibrosis (CF) patients is increasing. OBJECTIVES: To evaluate the effects of ceragenins, non-peptide mimics of antimicrobial peptides, against both planktonic and biofilm forms of S. maltophilia and the cytotoxicity of ceragenins to the IB3-1 CF cell line. METHODS: Ceragenin CSA-131, with and without 5% Pluronic® F127 (a non-ionic amphiphilic poloxamer), and ceragenin CSA-13 were evaluated against S. maltophilia clinical isolates (n = 40). MICs and MBCs of ceragenins and conventional antibiotics were determined. Time-kill curve experiments were performed with 1×, 2× and 4× MICs of ceragenins. The highest non-cytotoxic concentrations of ceragenins against IB3-1, a CF cell line, were determined by MTT assay. The effects of ceragenins against biofilm adhesion, formation and mature biofilms were investigated. RESULTS: CSA-131 with Pluronic® F127 displayed the lowest MICs (MIC50/MIC90: 1/2 mg/L) followed by CSA-131 (MIC50/MIC90: 2/4 mg/L), while those of CSA-13 were much higher (MIC50/MIC90: 16/32 mg/L). According to time-kill curve results, all concentrations at 4× MICs of ceragenins showed bactericidal activity (3 log reduction) after 4 h. While CSA-131 and CSA-131-poloxamer inhibited biofilm adhesion and formation by 87.74% and 83.42%, respectively, after 24 h, CSA-131 was more effective on mature biofilms. Formulating CSA-131 in poloxamer micelles did not affect the cytotoxicity of CSA-131 to IB3-1 cells. CONCLUSIONS: CSA-131 could be a potential antimicrobial agent for the treatment of S. maltophilia infections in CF, due to its low cytotoxicity on the CF cell line and good antimicrobial and antibiofilm effects.


Subject(s)
Cystic Fibrosis , Stenotrophomonas maltophilia , Anti-Bacterial Agents/pharmacology , Biofilms , Cystic Fibrosis/complications , Humans , Microbial Sensitivity Tests , Poloxamer , Steroids
10.
Mikrobiyol Bul ; 54(4): 638-646, 2020 Oct.
Article in Turkish | MEDLINE | ID: mdl-33107293

ABSTRACT

Bloodstream infections due to yeast species especially Candida spp. have been reported to be important healthcare associated infections with high mortality and morbidity rates. Candidemia causes prolonged hospital stays as well as increased cost. In order to prevent or treat these life-threatening bloodstream infections successfully, nationwide epidemiological data should be available about the etiological agents of these infections. Multi-centre national epidemiological data on yeast bloodstream infections in Turkey is lacking. A retrospective study was designed and data from six different centres in Turkey between 2011 and 2016 years were gathered and analysed for the distribution and frequency of yeast species in order to assist clinicians in their choice of early and appropriate antifungal therapy. All laboratories used automated blood culture systems for the isolation of blood strains. All the participating centres performed the identification of their own isolates by conventional methods using germ tube test, morphology on corn meal agar with tween 80 and chromogenic media and the identification was confirmed by API 20C AUX, API ID 32C or matrix-assisted laser desorption/ionization time of flight mass spectrophotometry (MALDI-TOF MS) systems. The analysis of the results was performed on the basis of intensive care units (ICUs), other inpatient clinics (OICs) and totally all clinics (ACs). Totally 2547 yeast isolates were determined from six participating centres during six years. According to the total ACs results, Candida albicans was the most prevalent species (43.1%), followed by Candida parapsilosis complex (29.1%), Candida glabrata (10.1%), Candida tropicalis (7.5%), Candida krusei (2.4%) and Candida kefyr (1.6%) and the remaining (6.2%) of them consisted of other yeast species. The distribution of the Candida species did not show statistically significant difference between the years, however the increase of C.parapsilosis complex in 2016 was statistically significant, (p= 0.02). During the study period, totally 1054 yeast isolates were obtained from the ICUs of the centres. C.albicans predominated with 476 (45.2%) isolates and C.parapsilosis complex (28.7%), C.glabrata (10.7%) and C.tropicalis (7.3%) were the other leading species in ICUs. Among 1493 isolates of the OICs of six centres participated in the study, C.albicans was the most prevalent species with 622 (41.7%) isolates. The other frequent species of OICs were C.parapsilosis complex (29.5%), C.glabrata (9.6%) and C.tropicalis (7.6%) resembling ICU results. It can be concluded that C.albicans is still the leading cause of bloodstream infections in the six different centres located in various geographical areas of Turkey.


Subject(s)
Blood Culture , Antifungal Agents/pharmacology , Antifungal Agents/therapeutic use , Kluyveromyces , Microbial Sensitivity Tests , Phylogeny , Pichia , Retrospective Studies , Turkey/epidemiology
11.
Turk Pediatri Ars ; 55(2): 207-209, 2020.
Article in English | MEDLINE | ID: mdl-32684769

ABSTRACT

Invasive fungal infections may cause morbidity and mortality in pediatric patients with hematologic and oncologic malignancies treated with intensive protocols. We present a case of mucormycosis in an 8-year-old boy with acute lymphoblastic leukemia. In our patient, the suspicion for an oculoorbital and paranasal infection only due to mild pain in the orbital area without any abnormal pathologic findings in the ophthalmologic and otolaryngologic examination, led us to an early diagnosis. Despite the use of antifungal therapy, the lesion persisted and fever subsided after surgical drainage of the periorbital abscess. Antifungal treatment continued during chemotherapy. He has been in remission for four years. Mucormycosis should be in the differential diagnosis in infections in children with cancer, especially leukemia, according to clinical and radiologic findings. A high degree of suspicion and prompt systemic empirical antifungal therapy, as well as surgical debridement, are crucial for the survival of patients. Beside antifungals, early surgery plays an important role in patients with mucormycosis.

12.
Infect Drug Resist ; 12: 675-685, 2019.
Article in English | MEDLINE | ID: mdl-31114258

ABSTRACT

Objective: To identify epidemic and other transmissible Pseudomonas aeruginosa strains, genotypic analyses are required. The aim of this study was to assess the distribution of P. aeruginosa strains within the Turkish pediatric cystic fibrosis (CF) clinic population. Methods: Eighteen patients attending the pediatric CF clinic of Cerrahpasa Medical Faculty were investigated in the study. Throat swab and/or sputum samples were taken from each patient at 3-month intervals. The isolates of patients were analyzed by pulsed-field gel electrophoresis (PFGE). The intra- and interpatient genotypic heterogeneity of isolates was examined to determine the clonal isolates of P. aeruginosa within the cohort. Results: A total of 108 clinical isolates of P. aeruginosa were obtained from 18 patients between May 2013 and May 2014. The pulsotypes of the first patient's isolates could not be obtained by PFGE. From the remaining 17 patients and 101 isolates, 55 distinct pulsotypes were detected. The number of pulsotypes observed in more than one patient (minor clonal strains, cluster strains) was 8 (14.5%), and one of them colonized three patients. However, none of them was detected in more than three patients. These pulsotypes were composed of 20 isolates. In addition, with the PFGE analysis of 81 isolates, we detected 47 (85.6%) pulsotypes, which belonged to only one patient. Over different periods of this study, only 2 (11.8%) patients were colonized with the same pulsotype. Conclusion: Our study indicates that there was considerable genomic diversity among the P. aeruginosa isolates in our clinic. The presence of shared pulsotypes supports cross-transmission between patients.

13.
J Glob Antimicrob Resist ; 18: 230-234, 2019 09.
Article in English | MEDLINE | ID: mdl-30980958

ABSTRACT

OBJECTIVES: This study investigated the antifungal resistance rates of isolates from candidaemia patients in 12 tertiary-care centres in Turkey. METHODS: A total of 1991 Candida spp. isolates from 12 centres isolated from 1997-2017 were included in the study. Species/species complex (SC) identification was performed using conventional methods in all centres, occasionally accompanied by MALDI-TOF/MS. Antifungal susceptibility testing was performed for amphotericin B, fluconazole, itraconazole, posaconazole, voriconazole and micafungin (as echinocandin class representative) using the CLSI microdilution method. Resistance rates were determined according to CLSI clinical breakpoints (CBPs). For drugs and species with undetermined CBPs, epidemiological cut-off values were used for wild-type (WT)/non-WT categorisation. RESULTS: No or low rates of resistance were detected in general for tested Candida spp. isolates. Specifically, overall resistance to fluconazole in isolates of Candida parapsilosis SC and Candida glabrata SC were 7.7% and 0.9%, respectively. Resistance rates for C. parapsilosis SC varied extensively from one center to other (0-47.1%). Importantly, no echinocandin resistance was detected. Rates of non-WT isolates were also generally low: fluconazole against Candida lusitaniae, 4.3%; posaconazole against C. parapsilosis SC, 3.5%; posaconazole against Candida krusei, 1.9%; and voriconazole against C. glabrata SC, 0.5%. CONCLUSION: This is the first multicentre report of antifungal resistance rates among candidaemia isolates in Turkey, suggesting low resistance rates in general. Due to varying rates of fluconazole resistance in C. parapsilosis SC isolates that was detected at remarkably high levels in some centres, further studies are warranted to explore the source, clonal relatedness and resistance mechanisms of the isolates.


Subject(s)
Antifungal Agents/pharmacology , Candida/drug effects , Candidemia/microbiology , Drug Resistance, Fungal , Humans , Microbial Sensitivity Tests , Tertiary Care Centers , Turkey
14.
Mycopathologia ; 183(6): 913-920, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30187246

ABSTRACT

BACKGROUND: Aspergillus fumigatus is the species section Fumigati most frequently isolated from the respiratory tract of cystic fibrosis (CF) patients. Recent studies suggest that mutations in the Cyp51 gene, particularly TR34/L98H, are responsible for azole resistance. OBJECTIVES AND METHODS: The focus of this study was on section Fumigati isolates isolated from the respiratory tract samples of CF patients. More specifically, the goal was to detect A. fumigatus isolates, test their antifungal susceptibility to itraconazole, voriconazole and posaconazole, and finally determine the presence of TR34/L98H and other mutations in the isolates Cyp51A gene. RESULTS AND CONCLUSIONS: A set of 31 isolates of Aspergillus section Fumigati were obtained from the sputum samples of 6 CF patients and subsequently identified to species level by microsatellite genotyping. All isolates were determined as A. fumigatus and involved 14 different genotypes. The minimal inhibitory concentrations to the three azoles were determined by the E-test method, and the Cyp51A gene was sequenced. One of the genotypes was found to be resistant to all azoles but no mutations were detected in the Cyp51A gene, especially the TR34/L98H mutation. Therefore, mutations in genes other than Cyp51A or other distinct mechanisms may be responsible for this reported multiazole resistance found in a Turkish CF patient.


Subject(s)
Antifungal Agents/pharmacology , Aspergillus fumigatus/drug effects , Azoles/pharmacology , Drug Resistance, Fungal , Mutation , Pulmonary Aspergillosis/microbiology , Sterol 14-Demethylase/genetics , Adolescent , Adult , Aspergillus fumigatus/genetics , Aspergillus fumigatus/isolation & purification , Child , Cystic Fibrosis/complications , Female , Genotype , Genotyping Techniques , Humans , Male , Microbial Sensitivity Tests , Microsatellite Repeats , Middle Aged , Mycological Typing Techniques , Sequence Analysis, DNA , Sputum/microbiology , Turkey , Young Adult
15.
Turk Pediatri Ars ; 52(3): 145-153, 2017 Sep.
Article in English | MEDLINE | ID: mdl-29062248

ABSTRACT

AIM: Non-albicans Candida species and resistant microorganisms have been more commonly isolated in invasive candidiasis in recent years. The aim of this study was to evaluate the distrubution of Candida spp and antifungal resistance in our clinic. MATERIAL AND METHODS: Fifty-four Candida isolates and antifungal susceptibility results obtained from patients diagnosed as having invasive candidiasis between December 2012 and June 2016 were included. Clinical and laboratory data were retrospectively analyzed. E-test method was used in order to determine antifungal susceptibilities of Candida spp for amphotericin B, fluconazole, voriconazole, ketoconazole, itraconazole, anidulafungin, caspofungin, and flucytosine. RESULTS: The clinical diagnoses of the patients were candidemia (n=27, 50%), catheter-related blood stream infection (n=1, 1.8%), urinary tract infection (n=13, 24%), surgical site infection (n=4, 7.4%), intraabdominal infection (n=3, 5.5%), empyema (n=2, 3.7%), and pneumonia (n=4, 7.4%). The most common isolated agent was C. albicans (n=27, 50%) and the others were C. parapsilosis (n=13, 24%), C. tropicalis (n=6, 11.1%), C. glabrata (n=3, 5.6%), C. lusitaniae (n=2, 3.7%), and unspecified Candida spp. (n=3, 5.6%). Fluconazole resistance was 7.4% among all isolates. Resistance against itraconazole, ketoconazole, anidulafungin, voriconazole and caspofungin were 33.3%, 12.5%, 11.1%, 5%, and 2.5%, respectively. Isolates presented intermediate resistance against itraconazole (41.7%), voriconazole (5.6%), and amphotericin B (3.7%) to varying extents. All of the isolates were susceptible to flucytosine. CONCLUSIONS: In our clinic, C. albicans and non-albicans Candida species were equally distributed and antifungal susceptibilities against major antifungal agents such as fluconazole, amphotericin B, and caspofungin were found considerably high.

16.
Am J Infect Control ; 44(10): 1139-1143, 2016 10 01.
Article in English | MEDLINE | ID: mdl-27339794

ABSTRACT

BACKGROUND: The purpose of this study was to establish species distribution of Candida isolates from pediatric patients in Istanbul, Turkey, and to determine risk factors associated with nosocomial Candida infections. METHODS: This study was conducted between June 2013 and June 2014 by participation of 7 medical centers in Istanbul. Candida spp strains isolated from the clinical specimens of pediatric patients were included. Clinical features were recorded on a standardized data collection sheet. RESULTS: A total of 134 systemic Candida infections were identified in 134 patients. The patients were admitted in pediatric and neonatal intensive care units (41.8% and 9.7%, respectively) and in pediatric wards (48.5%). Candida albicans was the most prevalent species (47%), followed by Candida parapsilosis (13.4%), Candida tropicalis (8.2%), Candida glabrata (4.5%), Candida lusitaniae (3.7%), Candida kefyr (2.2%), Candida guilliermondii (1.5%), Candida dubliniensis (0.7%), and Candida krusei (0.7%). Types of Candida infections were candidemia (50.7%), urinary tract infection (33.6%), surgical site infection (4.5%), central nervous system infection (3.7%), catheter infection (3.7%), and intra-abdominal infection (3.7%). In multivariate analysis, younger age (1-24 months) and detection of non-albicans Candida spp was found to be risk factors associated with candidemia (P = 0.040; odds ratio [OR], 4.1; 95% confidence interval [CI], 1.06-15.86; and P = 0.02; OR, 2.4; 95% CI, 1.10-5.53, respectively). CONCLUSIONS: This study provides an update for the epidemiology of nosocomial Candida infections in Istanbul, which is important for the management of patients and implementation of appropriate infection control measures.


Subject(s)
Candida/isolation & purification , Candidemia/epidemiology , Candidiasis/epidemiology , Cross Infection , Urinary Tract Infections/epidemiology , Candida albicans/isolation & purification , Candidemia/microbiology , Candidiasis/microbiology , Child, Preschool , Female , Hospitals , Humans , Infant , Infant, Newborn , Intensive Care, Neonatal , Male , Risk Factors , Turkey/epidemiology , Urinary Tract Infections/drug therapy , Urinary Tract Infections/microbiology
17.
Mycoses ; 58(10): 588-97, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26293550

ABSTRACT

Although conventional identification of pathogenic fungi is based on the combination of tests evaluating their morphological and biochemical characteristics, they can fail to identify the less common species or the differentiation of closely related species. In addition these tests are time consuming, labour-intensive and require experienced personnel. We evaluated the feasibility and sufficiency of DNA extraction by Whatman FTA filter matrix technology and DNA sequencing of D1-D2 region of the large ribosomal subunit gene for identification of clinical isolates of 21 yeast and 160 moulds in our clinical mycology laboratory. While the yeast isolates were identified at species level with 100% homology, 102 (63.75%) clinically important mould isolates were identified at species level, 56 (35%) isolates at genus level against fungal sequences existing in DNA databases and two (1.25%) isolates could not be identified. Consequently, Whatman FTA filter matrix technology was a useful method for extraction of fungal DNA; extremely rapid, practical and successful. Sequence analysis strategy of D1-D2 region of the large ribosomal subunit gene was found considerably sufficient in identification to genus level for the most clinical fungi. However, the identification to species level and especially discrimination of closely related species may require additional analysis.


Subject(s)
DNA, Fungal/isolation & purification , Fungi/classification , Fungi/genetics , Mycological Typing Techniques , Ribosome Subunits, Large/genetics , Sequence Analysis, DNA , Aspergillus/classification , Aspergillus/isolation & purification , Candida/classification , Candida/isolation & purification , DNA, Fungal/genetics , Filtration/instrumentation , Fungi/isolation & purification , Fusarium/classification , Fusarium/isolation & purification , Humans , Polymerase Chain Reaction , Yeasts/classification , Yeasts/genetics , Yeasts/isolation & purification
18.
Ann Clin Microbiol Antimicrob ; 13: 28, 2014 Aug 13.
Article in English | MEDLINE | ID: mdl-25123237

ABSTRACT

BACKGROUND: Isolation of mycobacteria in cystic fibrosis (CF) patients is increasingly being reported. Because of having long term antimicrobial treatment, CF patients are at risk of pulmonary infection with especially resistant nontuberculous mycobacteria (NTM) strains. The aim of the present study is to determine the prevalence of mycobacterium spp. and antimicrobial susceptibility in Turkish CF patients. METHODS: During a 5.5 year study period, 376 sputa from 130 CF patients were analyzed. Antimycobacterial susceptibility testing was performed by the Bactec 460 TB System and the E test method. RESULTS: Totaly 28 (7.44%) Mycobacterium spp. were isolated from eight (6.15%) CF patients. Five isolates (17.9%) were identified as Mycobacterium tuberculosis complex (MTBC), 14 (50%) as Mycobacterium abscessus and nine (32.1%) as Mycobacterium lentiflavum. All MTBC isolates were found to be susceptible to streptomycin, isoniazid, rifampicin, and ethambutol. Resistance to some antibiotics was detected in some NTM strains. These are the first data about the prevalence of mycobacteria in CF patients from Turkey. CONCLUSIONS: In pediatric CF patients, specific mycobacterial analysis of sputum specimens and susceptibility testing should be performed for allowing early detection, identification and the possibility of eradication of these bacteria.


Subject(s)
Cystic Fibrosis/complications , Drug Resistance, Bacterial , Mycobacterium Infections, Nontuberculous/microbiology , Mycobacterium tuberculosis/drug effects , Nontuberculous Mycobacteria/drug effects , Tuberculosis/microbiology , Adolescent , Antitubercular Agents/pharmacology , Child , Child, Preschool , Female , Humans , Male , Microbial Sensitivity Tests , Mycobacterium Infections, Nontuberculous/epidemiology , Mycobacterium tuberculosis/isolation & purification , Nontuberculous Mycobacteria/isolation & purification , Prevalence , Sputum/microbiology , Tuberculosis/epidemiology , Turkey/epidemiology
19.
J Infect Dev Ctries ; 7(11): 888-91, 2013 Nov 15.
Article in English | MEDLINE | ID: mdl-24240049

ABSTRACT

INTRODUCTION: Staphylococcus aureus is one of the first bacteria colonizing in cystic fibrosis (CF) respiratory tract and different virulence factors are responsible for disease progression. It is not clear if CF S. aureus strains are more virulent than strains isolated from non-CF patients. METHODOLOGY: Biofilm production was detected by a modified tissue culture plate method, presence of genes encoding for Panton-Valentine leukocidin (PVL) was investigated by a signal amplified sandwich hybridization assay and antimicrobial susceptibility patterns were detected by disk diffusion method. RESULTS: Staphylococcus aureus clinical isolates (n = 88) recovered from respiratory tract specimens in which 31 of them were from cystic fibrosis (CF) patients were analysed. Biofilm production was detected in 96.8% of CF isolates in which 32.3% exhibited strong positive phenotype and in 47.4% of non-CF isolates in which strong positive phenotype was not observed (p <0.05). All CF isolates were methicillin susceptible, whereas 53.4% of non-CF isolates (n = 31) were methicillin resistant. No resistance was observed for vancomycin, chloramphenicol and trimethoprim/sulfamethoxazole in any of the isolates. PVL genes were detected only in two isolates (2.3%), one from each group, CF and non-CF, which both were methicillin susceptible. CONCLUSION: Biofilm rather than PVL production appears to be an important virulence factor in CF patients.


Subject(s)
Bacterial Toxins/genetics , Biofilms/growth & development , Exotoxins/genetics , Leukocidins/genetics , Respiratory System/microbiology , Respiratory Tract Infections/microbiology , Staphylococcal Infections/microbiology , Staphylococcus aureus/genetics , Staphylococcus aureus/physiology , Humans , Microbial Sensitivity Tests , Nucleic Acid Hybridization , Staphylococcus aureus/isolation & purification
20.
Ann Clin Microbiol Antimicrob ; 12: 33, 2013 Nov 21.
Article in English | MEDLINE | ID: mdl-24261745

ABSTRACT

AIM: Mycobacteria other than tuberculosis (MOTT) cause increasingly serious infections especially in immunosuppressive patients by direct transmission from the environment or after colonization. However, identification of these species is difficult because of the cost and difficulties in defining to species level. Identification and distribution of these species can help clinician in the choice of treatment. MATERIALS AND METHODS: A total of 90 MOTT strains obtained from four different centers were included in the study. These strains were identified by sequence analysis of 16S rRNA and Hsp65 genetic regions. RESULTS: Accordingly, within the 90 MOTT strains, 17 different species were identified. In order of frequency, these species were M. gordonea (n = 21), M. abscessus (n = 13), M. lentiflavum (n = 9), M. fortuitum (n = 8), M. intracellulare (n = 6), M. kumamotonense (n = 6), M. neoaurum (n = 5), M. chimaera (n = 5), M. alvei (n = 5), M. peregrinum (n = 3), M. canariasense (n = 3), M. flavescens (n = 1), M. mucogenicum (n = 1), M. chelona (n = 1), M. elephantis (n = 1), M. terrae (n = 1) and M. xenopi (n = 1). Most frequently identified MOTT species according to the geographical origin were as follows: M. abscessus was the most common species either in Istanbul or Malatya regions (n = 6, n = 6, consequently). While M. kumamotonense was the most frequent species isolated from Ankara region (n = 6), M. gordonea was the most common for Samsun region (n = 14). CONCLUSION: Our study revealed that frequency of MOTT varies depending on the number of clinical samples and that frequency of these species were affected by the newly identified species as a result of the use of novel molecular methods. In conclusion, when establishing diagnosis and treatment methods, it is important to know that infections caused by unidentified MOTT species may vary according to the regions in Turkey. The results of the study showed that there were differences in the frequency of MOTT species in the different geographical regions of Turkey.


Subject(s)
Mycobacterium Infections, Nontuberculous/epidemiology , Mycobacterium Infections, Nontuberculous/microbiology , Nontuberculous Mycobacteria/classification , Nontuberculous Mycobacteria/isolation & purification , Bacterial Proteins/genetics , Chaperonin 60/genetics , DNA, Bacterial/chemistry , DNA, Bacterial/genetics , DNA, Ribosomal/chemistry , DNA, Ribosomal/genetics , Humans , Phylogeography , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , Topography, Medical , Turkey
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