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1.
Pediatr Infect Dis J ; 2023 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-37922485

RESUMEN

BACKGROUND: With recent developments in the field of microbiology, an increasing number of yeasts and molds with the potential to cause infections in humans are identified every year. In addition to the challenges in identifying clinical isolates, there is limited antifungal susceptibility data available for Phialemonium species, leading to uncertainty in optimal treatment recommendations. METHODS: In this article, catheter-related bloodstream infections caused by Phialemonium curvata (previously Phialemonium curvatum ) in 3 immunosuppressed patients are presented. Furthermore, the literature was reviewed to identify the clinical spectrum and treatment approaches for the reported infections. RESULTS: The cases presented here were analyzed along with 24 cases reported in the literature. Among all cases, 21 (77.7%) patients had an underlying condition. Nine (33.3%) patients had hematological/oncological malignancies and solid organ transplants. Twenty-two (81.4%) patients had a history of device or invasive interventions. Surgical procedures, removal of contaminated devices or tissue were found to reduce the risk of death by 86.7%. Correspondence analysis revealed a significant association between antifungal treatment and outcome ( P < 0.001). The correspondence analysis could explain 53.9% of this relationship. Monotherapy and combination therapy were associated with survival. While salvage treatment or no antifungal therapy was associated with mortality, intravitreal injection or topical application of voriconazole was associated with sequelae. CONCLUSIONS: Surgical intervention and removal of contaminated devices or tissue should be considered at an early stage.

2.
J Mycol Med ; 33(3): 101382, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37060850

RESUMEN

Although Fusarium spp. rarely cause infections in healthy people, they can cause fusariosis, particularly in neutropenic hematological malignancies, bone marrow transplant patients, and immunocompromised patients, such as those with acquired immune deficiency syndrome (AIDS), and rarely in solid organ transplant recipients. Here, we present a case of a liver transplant recipient with F. solani species complex (FSSC) infection treated with posaconazole. A 61-year-old man presented with multiple itchy, painful, palpable, irregular, subcutaneous nodules on the right leg and total dystrophic onychomycosis in the right toenails. Incisional skin biopsies of the lesions were performed, and the samples were sent to the pathology and mycology laboratories for analysis. The clinical isolate was identified as FSSC using phenotypic, matrix-assisted laser desorption/ionization-time of flight mass spectrometry, and genotypic methods. Liposomal amphotericin B could not be administered owing to the development of side effects; hence, the patient was treated with posaconazole for 4 months. While some nodular lesions disappeared completely under this treatment, the others showed dimensional regression. This is the first case of FSSC infection with skin and nail involvement in a non-neutropenic, liver transplant patient in Turkey. Fusariosis may develop with rare species, such as FSSC, as first reported in this case of a liver transplant patient. Regardless of the species, amphotericin B is the first choice for treating fusariosis; however, posaconazole is an effective and safe alternative to amphotericin B.


Asunto(s)
Fusariosis , Fusarium , Trasplante de Hígado , Masculino , Humanos , Persona de Mediana Edad , Fusariosis/diagnóstico , Fusariosis/tratamiento farmacológico , Anfotericina B/uso terapéutico , Antifúngicos/uso terapéutico
3.
Mikrobiyol Bul ; 55(3): 452-460, 2021 Jul.
Artículo en Turco | MEDLINE | ID: mdl-34416810

RESUMEN

Candida auris is a fungal pathogen that was first identified in 2009. Since its definition, it has spread globally and has caused life-threatening nosocomial infections. Increases in the number of immunocompromised individuals, empirical use of broad-spectrum antimicrobials and widespread use of catheterizations are the predisposing factors in the development of infection. There are problems for the identification of C.auris with the routine methods. In this case report, infections with C.auris, isolated for the first time from three patients in our hospital's intensive care units (ICU) between November 2020-January 2021, were presented. The first case was a 46-year-old male patient with laryngeal carcinoma who developed cardiopulmonary arrest during anesthesia induction in the tumor operation, and was followed up in the ICU. C.auris growth was detected in the blood and intravenous (IV) catheter tip cultures on the 66th day of admittance. Cure achieved on the 24th day under caspofungin treatment as no growth was determined. Second case was a 71-year-old female patient admitted to the emergency department with shortness of breath and general condition disorder that developed after COVID-19 infection and hospitalized in ICU with the diagnosis of pneumonia and acute renal failure. In the 16th day of admittance C.auris growth was detected in blood and from catheter tip cultures and the patient died in the 18th day. The third case was a 49-year-old male patient, followed up in ICU with the diagnosis of subarachnoid hemorrhage after he admitted to the emergency department with confusion. In the 35th day of admittance, 100000 CFU/ mL C auris growth was detected in urine culture. The patient was accepted as asymptomatic fungiuria and followed up in the ICU. It was determined that the three patients were intubated, had urinary and femoral venous catheters and were being followed under wide spectrum antibiotherapy when the growth of C.auris was detected. Isolates identified as C.auris by MALDI-TOF Microflex LT/SH Smart MS in the Medical Microbiology Laboratory were then confirmed by conventional methods and DNA sequencing in the National Mycology Reference Laboratory. Antifungal susceptibility tests were performed by broth microdilution method. Fluconazole MIC values were >256 mg/ml for all cases. Long-term survival in hospital environments, colonization on skin, resistance to disinfectants of C.auris, facilitate the spread of the fungi and resistance to antifungals lead to treatment failures. In this case report, it was aimed to draw attention to the infections with C.auris, its diagnosis and risk factors.


Asunto(s)
COVID-19 , Candida , Anciano , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Turquía
4.
Mikrobiyol Bul ; 52(3): 247-258, 2018 Jul.
Artículo en Turco | MEDLINE | ID: mdl-30156511

RESUMEN

Fusarium species have gained importance as a cause of keratitis. The pathogenicity and virulence factors of genus Fusarium remain largely unknown. Several putative virulence factors have been reported for fungal pathogens, including biofilm formation, production of proteinases and other hydrolytic enzymes. It has been emphasized that Fusarium species are generally resistant to antifungals but the resistance may vary depending on the species and even according to the isolate. For this reason, pathogenic features and antifungal susceptibility of the clinical isolates gained importance for the management of keratitis cases. The aim of this study was to identify clinical Fusarium isolates, to evaluate their virulence factors and to show antifungal susceptibility patterns. The identification of Fusarium was made on genus level isolated from 25 keratitis cases. Among them, 13 of the isolates were identified by ITS sequencing on species complex level. The production of hemolytic activity, caseinase, esterase, proteinase and phospholipase activity were investigated in 13 of the isolates. Biofilm production was searched among all 25 isolates. Galleria mellonella larvae was used as in vivo infection model. Antifungal susceptibility for amphotericin B, itraconazole, voriconazole and posaconazole was performed according to the Clinical and Laboratory Standards Institute (CLSI) M38-A2 microdilution assay guidelines. As the subcommittee on antifungal susceptibility tests did not determine the clinical resistance breakpoints (CBP) specific to Fusarium species complex, the epidemiological cut off values (ECV) were used for the interpretation of the minimum inhibitory concentration (MIC) values of the antifungal drugs. Isolates were identified as six F.oxysporum, six F.solani species complex and one F.brachygibbosum. One F.solani, one F.oxysporum were positive for hemolytic activity; all isolates were caseinase positive; three F.oxysporum and two F.solani isolate were esterase positive; one F.solani isolate was proteinase positive; five F.oxysporum and two F.solani isolates were phospholipase positive; biofilm activity was positive in 52% of the 25 isolates. The larvae survived for seven days after Fusarium inoculation in the G.mellonella larvae model. MIC range was 0.5-8 µg/ml for amphotericin B, 2-32 µg/ml for itraconazole, 0.5-8 µg/ml for voriconazole, 0.5-16 µg/ml for posaconazole and according to the ECV values F.solani and F.oxysporum isolates were determined as wild type for four antifungal agents. As a result, it was shown that Fusarium isolates have some virulence factors, there was a concordance between in vitro virulence properties and in vivo virulence characteristics and some of the isolates were classified as antifungal susceptible wild type isolates.


Asunto(s)
Fusarium , Queratitis , Antifúngicos/farmacología , ADN Espaciador Ribosómico/genética , Fusarium/efectos de los fármacos , Fusarium/enzimología , Fusarium/genética , Humanos , Queratitis/microbiología , Pruebas de Sensibilidad Microbiana , Factores de Virulencia/genética
5.
Mikrobiyol Bul ; 51(2): 183-190, 2017 Apr.
Artículo en Turco | MEDLINE | ID: mdl-28566083

RESUMEN

Coccidioidomycosis caused by Coccidioides immitis or Coccidioides posadasii is a rare infectious disease except in endemic regions. In this report the third documented imported case of coccidioidomycosis in Turkey was presented. A thirty-year-old male patient was admitted to our hospital with fever and purulent drainage from his chest tube. He had worked in Arizona, USA, until 4 months before this presentation. While in Arizona, he experienced cough and hemoptysis and was diagnosed as pulmonary coccidioidomycosis. He was treated with itraconazole for two months and he had no symptoms for 3 years. He then returned to Turkey and 2 months after his return to Turkey, he was admitted to another hospital in Istanbul with dyspnea and diagnosed as hydro-pneumothorax, and pleural fluid obtained from the inserted chest tube was found to be purulent. One gram of BID amoxicillin-clavulanate was given. Physical examination on admission revealed a purulent drainage on the right side chest tube, a temperature of 38.5°C and decreased breath sounds on the right lung. Piperacillin-tazobactam 3 x 4.5 g intravenous and fluconazole 400 mg intravenous once daily were started. Human immunodeficiency virus test was negative. Gram-negative diplococci and rods, gram-positive cocci and septate hyphae were seen in the Gram stain of his pleural fluid. Pleural fluid culture revealed Moraxella catarrhalis after 24 hours incubation and a mold after 72 hours of incubation. Anti-coccidioidal antibodies were found positive in a titer of 1/2. Hydro-pneumothorax, atelectasis and a 3 mm nodules in the right lung were seen in his thorax CT. The patient's pleural fluid and the culture plates were sent to the Public Health Institute of Turkey, Mycology Reference Laboratory (PHIT-MRL), with a clinical suspicion of coccidioidomycosis. The specimen and plates were submitted to the PHIT-MRL Bio Safety Level-3 laboratory for mycological evaluation. The microscopic examination of 15% KOH preparations of pleural fluid specimens revealed septate hyphae which appear to be in the early stages of forming arthroconidia. The pleural fluid culture grew buff-white coloured colonies with aerial hyphae, which were suspected of being a Coccidioides spp. The strain was identified as C.immitis/posadasii by direct microscopy and culture, and subsequently confirmed by the FDA-approved DNA probe. DNA sequence analysis of the ITS and D1/D2 rDNA regions confirmed the isolate to be C.posadasii species [ITS 100% match to GenBank Accession No. AB232901 (630/630 base pair match), and D1/D2 100% match to GenBank Accession No. AB232884 (617/617 base pair match)]. ITS1 and ITS2 barcode analysis also confirmed the species to be C.posadasii, which is the species endemic in Arizona. Susceptibility testing was performed according to Clinical and Laboratory Standards Institute M38-A2 guidelines in the Fungus Testing Laboratory of the University of Texas Health Science Center at San Antonio and minimal inhibitory concentration values were; 0.125 µg/ml for amphotericin B, posaconazole and voriconazole, 0.5 µg/ml for itraconazole and 8 µg/ml for fluconazole. He had decortication of the pleura and was discharged from hospital after six weeks treatment with intravenous fluconazole which was continued orally for one year. Anti-coccidioidal antibodies were negative after two months of treatment. The patient is currently asymptomatic. The presented case is the third case reported from Turkey and provides additional contribution to the existing literature with regard to the appearance of arthroconidium, which is the unusual hyphal form, instead of the expected spherules in the infected tissue.


Asunto(s)
Antifúngicos/uso terapéutico , Coccidioides/aislamiento & purificación , Coccidioidomicosis/microbiología , Adulto , Combinación Amoxicilina-Clavulanato de Potasio/farmacología , Combinación Amoxicilina-Clavulanato de Potasio/uso terapéutico , Antifúngicos/farmacología , Arizona , Coccidioides/efectos de los fármacos , Coccidioides/crecimiento & desarrollo , Coccidioidomicosis/tratamiento farmacológico , Fluconazol/farmacología , Fluconazol/uso terapéutico , Humanos , Itraconazol/farmacología , Itraconazol/uso terapéutico , Masculino , Ácido Penicilánico/análogos & derivados , Ácido Penicilánico/farmacología , Ácido Penicilánico/uso terapéutico , Piperacilina/farmacología , Piperacilina/uso terapéutico , Combinación Piperacilina y Tazobactam , Pleura/microbiología , Recurrencia , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/crecimiento & desarrollo , Esporas Fúngicas/aislamiento & purificación , Viaje , Turquía
6.
Arq Bras Oftalmol ; 79(4): 261-3, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27626154

RESUMEN

Conjunctival ulceration accompanied with secretion and pain was observed in a 30-year-old male, 3 days after a perforating corneal trauma. Cultures of conjunctival ulcer samples grew Fonsecaea pedrosoi, a major causative agent of chromoblastomycosis that is typically transmitted during trauma. The conjunctival ulcer was successfully treated with amphotericin B, itraconazole, and fluconazole. This case report summarizes the diagnosis and treatment of a conjunctival ulcer due to F. pedrosoi, which is a rare complication of contaminated ocular trauma. To the best of our knowledge, this is the first reported case of F. pedrosoi causing acute conjunctival ulceration in the literature.


Asunto(s)
Ascomicetos/patogenicidad , Cromoblastomicosis/microbiología , Enfermedades de la Conjuntiva/microbiología , Perforación Corneal/microbiología , Úlcera de la Córnea/microbiología , Adulto , Antifúngicos/uso terapéutico , Ascomicetos/aislamiento & purificación , Cromoblastomicosis/terapia , Enfermedades de la Conjuntiva/terapia , Córnea/microbiología , Perforación Corneal/complicaciones , Perforación Corneal/terapia , Úlcera de la Córnea/terapia , Humanos , Masculino , Resultado del Tratamiento
7.
Arq. bras. oftalmol ; 79(4): 261-263, July-Aug. 2016. graf
Artículo en Inglés | LILACS | ID: lil-794591

RESUMEN

ABSTRACT Conjunctival ulceration accompanied with secretion and pain was observed in a 30-year-old male, 3 days after a perforating corneal trauma. Cultures of conjunctival ulcer samples grew Fonsecaea pedrosoi, a major causative agent of chromoblastomycosis that is typically transmitted during trauma. The conjunctival ulcer was successfully treated with amphotericin B, itraconazole, and fluconazole. This case report summarizes the diagnosis and treatment of a conjunctival ulcer due to F. pedrosoi, which is a rare complication of contaminated ocular trauma. To the best of our knowledge, this is the first reported case of F. pedrosoi causing acute conjunctival ulceration in the literature.


RESUMO O quadro clínico de uma úlcera conjuntival acompanhada de secreção e dor foi observado em homem de 30 anos de idade, 3 dias após um trauma perfurante da córnea. As culturas de uma amostra retirada da úlcera conjuntival foi positiva para Fonsecaea pedrosoi, uma cromoblastomicose, geralmente transmitido após traumatismos. O caso foi tratado com sucesso com a anfotericina B, itraconazol e fluconazol. Este relato de caso reporta o diagnóstico e tratamento de uma úlcera conjuntival causada por F. pedrosoi, que raramente é visto nos olhos expostos a traumatismos contaminados. Até onde sabemos, este é o primeiro caso relatado na literatura de F. pedrosoi causando úlcera conjuntival aguda.


Asunto(s)
Humanos , Masculino , Adulto , Ascomicetos/patogenicidad , Úlcera de la Córnea/microbiología , Cromoblastomicosis/microbiología , Enfermedades de la Conjuntiva/microbiología , Perforación Corneal/microbiología , Ascomicetos/aislamiento & purificación , Úlcera de la Córnea/terapia , Cromoblastomicosis/terapia , Resultado del Tratamiento , Enfermedades de la Conjuntiva/terapia , Córnea/microbiología , Perforación Corneal/complicaciones , Perforación Corneal/terapia , Antifúngicos/uso terapéutico
8.
Mikrobiyol Bul ; 50(1): 122-32, 2016 Jan.
Artículo en Turco | MEDLINE | ID: mdl-27058336

RESUMEN

The Clinical and Laboratory Standards Institute (CLSI) Subcommittee on Antifungal Susceptibility Testing has newly introduced species-specific clinical breakpoints (CBPs) for fluconazole and voriconazole. When CBPs can not be determined, wild-type minimal inhibitory concentration (MIC) distributions are detected and epidemiological cutoff values (ECVs) provide valuable means for the detection of emerging resistance. The aim of this study is to determine triazole resistance patterns in Candida species by the recently revised CLSI CBPs. A total of 140 Candida strains isolated from blood cultures of patients with invasive candidiasis hospitalized in various intensive care units in Turkey and sent to our reference laboratory between 2011-2012, were included in the study. The isolates were identified by conventional methods, and susceptibility testing was performed against fluconazole, itraconazole and voriconazole, by the 24-h CLSI broth microdilution (BMD) method. Azole resistance rates for all Candida species were determined using the new species-specific CLSI CBPs and ECVs criteria, when appropriate. The species distribution of the isolates were as follows; C.parapsilosis (n= 31 ), C.tropicalis (n= 26 ), C.glabrata (n= 21), C.albicans (n= 18), C.lusitaniae (n= 16), C.krusei (n= 16), C.kefyr (n= 9), C.guilliermondii (n= 2), and C.dubliniensis (n= 1). According to the newly determined CLSI CBPs for fluconazole and C.albicans, C.parapsilosis, C.tropicalis [susceptible (S), ≤ 2 µg/ml; dose-dependent susceptible (SDD), 4 µg/ml; resistant (R), ≥ 8 µg/ml], and C.glabrata (SDD, ≤ 32 µg/ml; R≥ 64 µg/ml) and for voriconazole and C.albicans, C.parapsilosis, C.tropicalis (S, ≤ 0.12 µg/ml; SDD, 0.25-0.5 µg/ml; R, ≥ 1 µg/ml), and C.krusei (S, ≤ 0.5 µg/ml; SDD, 1 µg/ml; R, ≥ 2 µg/ml), it was found that three of C.albicans, one of C.parapsilosis and one of C.glabrata isolates were resistant to fluconazole, while two of C.albicans and two of C.tropicalis were resistant to voriconazole. The ECVs of 0.5 µg/ml for voriconazole and C.glabrata were used to differentiate wild-type (MIC ≤ ECV) from non-wild-type (MIC > ECV) strains. Five of C.glabrata were non-WT for voriconazole. Due to the lack of CBPs for the less common species, the ECVs for fluconazole, itraconazole and voriconazole, respectively, were used for C.lusitaniae (2 µg/ml, 0.5 µg/ml, 0.03 µg/ml), C.guilliermondii (8 µg/ml, 1 µg/ml, 0.25 µg/ml), C.dubliniensis (0.5 µg/ml, 0.25 µg/ml, 0.03 µg/ml), and C.kefyr (1 µg/ml, 0.015 µg/ml) to categorize isolates of these species as wild- and non-wild-type. When the ECVs were used for fluconazole, one each of C.lusitaniae, C.dubliniensis and C.kefyr; for voriconazole, three of C.lusitaniae and one of C.kefyr were detected as non-wild-type. Overall, a total of five Candida species were resistant to fluconazole and four to voriconazole and among these species one each of C.parapsilosis, C.tropicalis, C.glabrata, C.lusitaniae, C.kefyr and three of C.albicans exhibited cross-resistance at least against two azoles. It was concluded that, the strains identified as resistant and non-wild-type in this in vitro study should be supported by molecular and in vivo studies for the determination of their clinical validity.


Asunto(s)
Antifúngicos/farmacología , Candida/efectos de los fármacos , Candidiasis Invasiva/microbiología , Triazoles/farmacología , Candida/aislamiento & purificación , Relación Dosis-Respuesta a Droga , Farmacorresistencia Fúngica , Fluconazol/farmacología , Fungemia/microbiología , Humanos , Unidades de Cuidados Intensivos , Itraconazol/farmacología , Pruebas de Sensibilidad Microbiana , Especificidad de la Especie , Turquía , Voriconazol/farmacología
9.
Mycopathologia ; 181(5-6): 415-24, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26864747

RESUMEN

Serious mycological work requires a reliable source of cultures that are maintained under safe long-term storage. In this study, 1186 clinical fungal isolates consisting of molds (20 species in 11 genera) and yeasts (21 species in seven genera) maintained in water, under mineral oil at room temperature and cryopreserved at -80 °C for periods ranging from 1 to 12 years, were evaluated for their viabilities and stabilities. The strains were subcultured onto either Sabouraud dextrose agar or potato dextrose agar to determine the viabilities and purities. The stabilities of the dermatophytes were investigated using urease test medium, the Trichophyton agar test and morphological examination. The stabilities of yeasts were evaluated by microscopic morphology and by determining the antifungal susceptibilities of random samples of yeasts (n = 120). Additionally, 365 strains (dermatophytes, n = 115; yeasts, n = 250) were further characterized by "matrix-assisted laser desorption/ionization time-of-flight mass spectrometry." After 12 years of preservation, the survival rates with the three different preservation techniques, i.e., in water, under mineral oil and by freezing, were assessed as 94.7, 82.0 and 97.4 %, respectively. Viability was generally unrelated to the duration of storage. More stable and consistent growth was achieved after storage in water and freezing compared with mineral oil preservation. Our results demonstrate that the procedure for maintaining fungal cultures in water is a simple and inexpensive method, next to cryopreservation, and that both can be reliably used for the long-term preservation of most fungal isolates.


Asunto(s)
Hongos/fisiología , Viabilidad Microbiana , Preservación Biológica/métodos , Hongos/aislamiento & purificación , Técnicas Microbiológicas , Microscopía , Micosis/microbiología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Temperatura , Factores de Tiempo
10.
Curr Eye Res ; 41(8): 1050-1056, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26644282

RESUMEN

PURPOSE: Antifungal efficacy of photochemical cross-linking (PACK-CXL) with 0.1% and 0.25% riboflavin was evaluated with a comparative in vitro study. METHODS: Candida albicans and Aspergillus fumigatus ATCC reference strains, Candida parapsilosis, Aspergillus fumigatus, Fusarium solani, Scedosporium apiospermum, and Alternaria alternata strains isolated from keratitis cases were chosen as targeted microorganisms. Unique "black plate method" was developed in polystyrene microplates. Riboflavin suspensions in 0.1% and 0.25% were separately added into inoculated wells. Non-inoculated wells were filled by black colored dye in order to protect treated wells from reflection of UV treatment. After ultraviolet A (UVA) treatment, each well was evaluated by microbiological culture in order to count viable fungal colonies. Fungal killing rate was calculated by comparing fungal counts (CFU/mL) before and after UVA application of riboflavin-added wells. RESULTS: Four different fungal inoculum concentrations of targeted microorganisms, including 104, 103, 102, and 101 CFU/mL, were assayed. PACK-CXL with 0.25% riboflavin was found to be highly effective on fungal cells even in 104 CFU/mL of concentration. CONCLUSIONS: PACK-CXL appears as a promising treatment option for difficult-to-treat cases of fungal keratitis and 0.25% riboflavin concentration increases fungicidal effect of the procedure dramatically.


Asunto(s)
Infecciones Fúngicas del Ojo/tratamiento farmacológico , Queratitis/tratamiento farmacológico , Fotoquimioterapia/métodos , Riboflavina/farmacología , Rayos Ultravioleta , Colágeno/farmacología , Recuento de Colonia Microbiana , Reactivos de Enlaces Cruzados/farmacología , Infecciones Fúngicas del Ojo/microbiología , Hongos/aislamiento & purificación , Humanos , Queratitis/microbiología , Fármacos Fotosensibilizantes/farmacología
11.
Mikrobiyol Bul ; 49(2): 210-20, 2015 Apr.
Artículo en Turco | MEDLINE | ID: mdl-26167821

RESUMEN

Accurate and rapid identification of yeast isolates have become important in recent years for not only antifungal susceptibility testing due to the species-specific clinical resistance breakpoints but also early initiation of appropriate antifungal therapy. In clinical microbiology laboratories species identification of yeasts is often performed with several commercial systems based on biochemical properties and rarely according to the physiological and morphological characteristics. The aim of this study was to compare the two common commercial systems, VITEK 2 YST ID Card (Vitek; bioMérieux, France) and API 20C AUX (API; bioMérieux, France) with conventional mycological methods. A total of 473 clinical yeast strains isolated from clinical specimens in different university and training/research hospitals and identified by Vitek system were included in the study. The isolates were re-identified with API and conventional methods including morphological identification in the Mycology Reference Laboratory of the Public Health Institute of Turkey. Candida dubliniensis MYA 583, Candida krusei ATCC 6258, Candida parapsilosis ATCC 22019, Candida albicans ATCC 10231 and Cryptococcus neoformans ATCC 32268 were used as quality control strains and those standard strains were studied consecutively 10 days with both of the methods. The results of identification by Vitek and API were compared with the results of conventional methods for those 473 yeast isolates [6 genus (Candida, Cryptococcus, Blastoshizomyces, Rhodotorula, Saccharomyces, Trichosporon), 17 species (5 common and 12 rarely isolated)]. The performances of the systems were better (Vitek: 95%; API: 96%) for the commonly detected species (C.albicans, C.parapsilosis, C.glabrata, C.tropicalis and C.krusei) than those for rarely detected species (Vitek: 78.4%; API: 71.6%) (p= 0.155). Misidentification or unidentification were mostly detected for C.parapsilosis (Vitek: 6/87; API: 7/87) and C.glabrata (Vitek: 9/104; API: 3/104) by both of the systems. For rarely detected yeast isolates, misidentification or unidentification were most frequently observed in species of C.pelliculosa (Vitek: 3/11; API: 6/11) and C.dubliniensis (API and Vitek: 2/5) isolates. Candida guilliermondii (API: 2/5) isolates had lower rate of identification with API compared to other species. Blastoschizomyces capitatus and Saccharomyces cerevisiae isolates could not be identified by both of the systems. As a result, the accurate diagnosis of Vitek and API systems were similar in terms of consistency (86.3%). Two systems performed well in correct identification of common clinical yeast species (at least 95%), while the identification of rare species was more challenging indicating that they require further morphological and physiological testing. The addition of morphological identification to commercial systems will be useful for accurate diagnosis and treatment of mixed infections.


Asunto(s)
Micosis/diagnóstico , Levaduras/aislamiento & purificación , Servicios de Laboratorio Clínico , Farmacorresistencia Fúngica , Humanos , Laboratorios , Microbiología , Micosis/microbiología , Turquía , Levaduras/clasificación , Levaduras/efectos de los fármacos
12.
Mycopathologia ; 180(3-4): 165-71, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25971934

RESUMEN

Dermatophytes can invade the stratum corneum of the skin and other keratinized tissues and are responsible for a broad diversity of diseases of skin, nails and hair. Although the standard identification of dermatophytoses depends on macroscopic and microscopic characterization of the colonies grown on special media, there are a number of limitations owing to intraspecies morphological variability, atypical morphology or interspecies morphological similarity which entails improvement in the identification methods. Matrix-assisted laser desorption-ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a novel method which proved to be effective for rapid and reliable identification of dermatophytes grown in cultures when compared to conventional methods. We evaluated the performance of Bruker MALDI-TOF MS System (Bruker Daltonics, Germany) for identification of clinically relevant dermatophytes. In order to increase the identification capacity of the system, we created supplemental spectral database entries using ten reference dermatophyte strains (ten species in two genera). The utility of the generated database was then challenged using a total of 126 dermatophytes (115 clinical isolates and 11 additional reference strains). The results were evaluated by both manufacturer-recommended and lowered cutoff scores. MALDI-TOF MS provided correct identification in 122 (96.8 %) and 113 (89.7 %) of the isolates with the lowered scores and using the supplemented database, respectively, versus 65 (51.6 %) and 17 (13.5 %) correct identifications obtained by the unmodified database and recommended scores at the genus and species levels, respectively. Our results support the potential utility of MALDI-TOF MS as a routine tool for accurate and reliable identification of dermatophytes.


Asunto(s)
Arthrodermataceae/clasificación , Arthrodermataceae/aislamiento & purificación , Técnicas Microbiológicas/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , Tiña/diagnóstico , Arthrodermataceae/química , Humanos , Sensibilidad y Especificidad , Tiña/microbiología
13.
Case Rep Dermatol Med ; 2014: 563261, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25328721

RESUMEN

Rhodotorula spp. have emerged as opportunistic pathogens, particularly in immunocompromised patients. The current study reports a case of onychomycosis caused by Rhodotorula glutinis in a 74-year-old immunocompetent female. The causative agent was identified as R. glutinis based on the pinkish-orange color; mucoid-appearing yeast colonies on Sabouraud Dextrose Agar at 25°C; morphological evaluation in the Corn Meal-Tween 80 agar; observed oval/round budding yeast at 25°C for 72 hours; no observed pseudohyphae; positive urease activity at 25°C for 4 days; and assimilation features detected by API ID 32C kit and automated Vitek Yeast Biochemical Card 2 system. Antifungal susceptibility test results were as follows: amphotericin B (MIC = 0.5 µg/mL), fluconazole (MIC = 128 µg/mL), itraconazole (MIC = 0.125 µg/mL), voriconazole (MIC = 1 µg/mL), posaconazole (MIC = 0.5 µg/mL), anidulafungin (MIC = 0.5 µg/mL), and caspofungin (MIC = 16 µg/mL). Antifungal therapy was initiated with oral itraconazole at a dose of 400 mg/day; seven-day pulse therapy was planned at intervals of three weeks. Clinical recovery was observed in the clinical evaluation of the patient before the start of the third cure. Although R. glutinis has rarely been reported as the causative agent of onychomycosis, it should be considered.

14.
Mikrobiyol Bul ; 37(4): 269-76, 2003 Oct.
Artículo en Turco | MEDLINE | ID: mdl-14748264

RESUMEN

The aim of this study was to compare the different methods for the identification of Candida strains isolated from clinical specimens. The methods of germ tube examination, chlamydospore examination formed on the rice Tween-80 (RT-80) agar and evaluation of colony morphologies on the two chromogenic agars (CHROMagar Candida, Albicans ID), were compared with a reference API 20C AUX (bioMerieux, France) automated system based on the carbohydrate assimilation, for the identification of a total 255 Candida isolates. Of them, 173 (67.8%) were identified as C. albicans, 37 (14.5%) were C. glabrata, 23 (9%) were C. krusei, 9 (3.5%) were C. tropicalis, 9 (3.5%) were C. kefyr, 2 (0.8%) were C. guillermondii and 2 (0.8%) were C. parapsilosis, by API 20C AUX system. In the view of these results, 146 (84.4%) of C. albicans strains were identified by germ tube examination, 161 (93.1%) of C. albicans strains and 208 (81.5%) of total strains were identified by chlamydospore examination. 169 (97.7%) of C. albicans strains and 231 (90.6%) of total strains were identified by CHROMagar Candida method, and 168 (97.1%) of C. albicans strains were identified by Albicans ID method, correctly. In the CHROMagar Candida medium, 169 C. albicans isolates have produced bright green colored colonies, whereas 33 (89.2%) isolates which produced dark pink/purple colored colonies were identified as C. glabrata, 7 (77.8%) isolates which produced metalical blue colored colonies were identified as C. tropicalis and 22 (95.6%) isolates which produced pale pink colored colonies were identified as C. krusei. In the Albicans ID medium, four of the 172 isolates which were evaluated as C. albicans initially by producing blue colored colonies, have been identified as C. tropicalis by API 20C AUX system. The sensitivities and specificities of germ tube examination, RT-80, CHROMagar Candida and Albicans ID methods were found as follows, respectively; 84.4% and 100%, 93.1% and 100%, 97.7% and 100%, 99.4% and 95.3 percent. In conclusion, CHROMagar Candida medium seems the most favorable rapid and practical method with high sensitivity and specificity for the identification of Candida species, but its cost-effectiveness should be kept in view.


Asunto(s)
Candida/aislamiento & purificación , Técnicas de Tipificación Micológica/métodos , Candida/clasificación , Candida/crecimiento & desarrollo , Compuestos Cromogénicos/economía , Análisis Costo-Beneficio , Medios de Cultivo/economía , Humanos , Técnicas de Tipificación Micológica/economía , Sensibilidad y Especificidad
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