Utility of the Aspergillus galactomannan antigen testing for neutropenic paediatric patients.

Invasive aspergillosis (IA) is an increasingly important cause of morbidity and mortality particularly in paediatric patients. Early diagnosis and the initiation of efficacious antifungal treatments could affect the prognosis of these patients. The aim of this study was to determine the clinical contribution of Galactomannan (GM) screening in paediatric patients. We reviewed the records of all in-patients, and followed up, in the various units at the Medical Faculty Children's Hospital of Erciyes University (Kayseri, Turkey), those who had at least one GM assay result from August 2009 to April 2012. Paediatric patients were classified as proven, probable or possible, according to the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG). Twenty-five patients, with proven IA (n=3), probable IA (n=9) and possible IA (n=13) were included in the study. The GM antigen assay results were analysed in 158 blood samples from 47 patients. At the cut-off value of 0.5 ng/ml, the sensitivity was 68% [95% confidence interval (CI); 47-85]; specificity, 77% (95% CI; 55-92). To obtain more accurate results with GM testing, the diagnosis of IA should be confirmed by clinical investigation and the factors causing false positivity of the test should also be considered.

Molecular epidemiology and antifungal susceptibility of Saprochaete capitata (Blastoschizomyces capitatus) isolates causing nosocomial infection in Kayseri/Turkey.

BACKGROUND: Saprochaete capitata isolates have emerged as important nosocomial pathogens, among immunosuppressed or neutropenic patients, and a rare cause of nosocomial infection in the hematology-bone marrow unit (HBMU) and the intensive care unit (ICU). The purpose of this study was to molecular epidemiology and antifungal susceptibility of S. capitata (Blastoschizomyces capitatus) isolates causing nosocomial infection at Kayseri in Turkey. METHODS: During a period from 2012 to 2015, a total of 20 S. capitata strains were obtained from patients hospitalized at Erciyes University Hospital. The identification of S. capitata was performed by phenotypic and biochemical methods; this was confirmed by molecular methods by DNA sequencing analysis. Genotyping of S.capitata isolates from different patients was determined to by the repetitive sequence PCR (repPCR) using the DiversiLab System (BioMerieux). RESULTS: More than half of the patients with S. capitata infections were hospitalized in the hematology-oncology unit (60%). The patients mainly included those using intravascular devices (90%), and receiving parenteral antibiotics (85%); the mortality rate was 55%. The microbiological investigation failed to identify S. capitata in the hospital environment. All isolates were resistant to caspofungin (>32). However, the MIC90 values for voriconazole, amphotericin B, and fluconazole against all of the isolates were 0.125, 0.25, and 1µg/ml, respectively. The S. capitata strains belonged to five clones (A-E) which were determined by the use of rep-PCR and Clone C was found to be predominant. CONCLUSIONS: S. capitata isolates are an important cause of nosocomial infection in the HBMU and ICUs.

Conventional Morphology Versus PCR Sequencing, rep-PCR, and MALDI-TOF-MS for Identification of Clinical Aspergillus Isolates Collected Over a 2-Year Period in a University Hospital at Kayseri, Turkey.

BACKGROUND: Aspergillus species cause a wide range of diseases in humans, including allergies, localized infections, or fatal disseminated diseases. Rapid detection and identification of Aspergillus spp. facilitate effective patient management. In the current study we compared conventional morphological methods with PCR sequencing, rep-PCR, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) for the identification of Aspergillus strains. MATERIALS AND METHODS: A total of 24 consecutive clinical isolates of Aspergillus were collected during 2012-2014. Conventional morphology and rep-PCR were performed in our Mycology Laboratory. The identification, evaluation, and reporting of strains using MALDI-TOF-MS were performed by BioMérieux Diagnostic, Inc. in Istanbul. DNA sequence analysis of the clinical isolates was performed by the BMLabosis laboratory in Ankara. RESULTS: Samples consisted of 18 (75%) lower respiratory tract specimens, 3 otomycosis (12.5%) ear tissues, 1 sample from keratitis, and 1 sample from a cutaneous wound. According to DNA sequence analysis, 12 (50%) specimens were identified as A. fumigatus, 8 (33.3%) as A. flavus, 3 (12.5%) as A. niger, and 1 (4.2%) as A. terreus. Statistically, there was good agreement between the conventional morphology and rep-PCR and MALDI-TOF methods; kappa values were κ = 0.869, 0.871, and 0.916, respectively (P < 0.001). CONCLUSION: The good level of agreement between the methods included in the present study and sequence method could be due to the identification of Aspergillus strains that were commonly encountered. Therefore, it was concluded that studies conducted with a higher number of isolates, which include other Aspergillus strains, are required.

Antifungal Activity of Propolis Against Yeasts Isolated From Blood Culture: In Vitro Evaluation.

BACKGROUND: Due to the failure of available antifungal agents in the treatment of candidemia and the toxic activities of these drugs, a lot of researches are being conducted to develop new nontoxic and effective antifungal agents for optimal control of fungal pathogens. The aim of this study is to evaluate the in vitro antifungal activity of propolis against yeasts isolated from the blood cultures of intensive care unit patients. METHODS: Seventy-six strains were included in this study. The in vitro antifungal activity of propolis, fluconazole (FLU), and itraconazole (ITR) was investigated by the microdilution broth methods (CLSI guidelines M27-A3 for yeast). The propolis sample was collected from Kayseri, Turkey. RESULTS: Of the 76 isolates, 33 were identified as Candida albicans while 37 were C. parapsilosis, three were C. tropicalis, and three were identified as C. glabrata. The geometric mean range for MIC (µg/ml) with regard to all isolates was 0.077 to 3 µg/ml for FLU and ITR, and 0.375 to 0.70 µg/ml for propolis. It was shown that propolis had significant antifungal activity against all Candida strains and the MIC range of propolis was determined as 0185 to 3 µg/ml. CONCLUSION: This study demonstrated that propolis had significant antifungal activity against yeasts isolated from blood culture compared with FLU and ITR. The propolis MIC in azole-resistant strains such as C. glabrata was found lower than the FLU MIC.

Investigation of the relationship between virulence factors and genotype of Candida spp. isolated from blood cultures.

INTRODUCTION: The aim of study was to investigate the virulence factors of phospholipase, proteinase, esterase production and biofilm formation in Candida species isolated from patients with candidemia, and to assess their relationship with Candida genotypes derived after repetitive sequence-based polymerase chain reaction (rep-PCR) fingerprinting. METHODOLOGY: Fifty-two strains were identified to species level according to conventional methods and sequencing. The DiversiLab system was used for the genotyping. Enzyme activities and biofilm formation were evaluated using microbiological methods. RESULTS: The 52 strains were identified as follows: 29 C. parapsilosis, 19 C. albicans, 2 C. glabrata, and 2 C. tropicalis. Phospholipase and proteinase activities were observed to have statistically significant differences between C. albicans and non-albicans Candida (NAC) strains (p < 0.05), with C. albicans strains showing higher virulence. Rep-PCR revealed eight major genotypes (A-H).The 19 C. albicans and the 33 non-albicans Candida isolates yielded seven (A-G) and four (A, B, C, H) genotypes, respectively. C. albicans strains were not shown to have a predominant genotype and showed higher phospholipase and proteinase activitiy than did NAC, regardless of genotype. Genotype H (52%) was the predominant genotype for the NAC including 27 C. parapsilosis strains, but the majority of strains showed low virulence. CONCLUSIONS: NAC species were the most common causative agent for candidemia. Genotyping showed low transmission of C. albicans strains, but transmission of C. parapsilosis was high. In candidemia, several Candida virulence factors may be responsible at the same time. However, different genotypes of Candida strains showed different virulence activity.

Biological NOx removal by denitrification process in a jet-loop bioreactor: system performance and model development.

Nitrogen monoxide (NO) and nitrogen dioxide referred as NOx are one of the most important air pollutants in the atmosphere. Biological NOx removal technologies have been developing to reach a cost-effective control method for upcoming stringent NOx emission standards. The BioDeNOx system was seen as a promising biological NOx control technology which is composed of two reactors, one for absorbing of NO in an aqueous Fe(II)EDTA2- solution and the other for subsequent reduction to N2 gas in a biological reactor by the denitrification process. In this study, instead of two discrete reactors, only one jet-loop bioreactor (JLBR) was utilized as both absorption and denitrification unit and no chelate-forming chemicals were added. In other words, the advantage of better mass transfer conditions of jet bioreactor was used instead of Fe(II)EDTA2-. The process was named as Jet-BioDeNOx. The JLBR was operated for the removal of NOx from air streams containing 500-3000 ppm NOx and the results showed that the removal efficiency was between 81% and 94%. The air to liquid flow ratio (Q(G)/Q(RAS)) varied in the range of 0.07-0.12. Mathematical modelling of the system demonstrated that the removal efficiency strongly depends on this ratio. The high mass transfer conditions prevailed in the reactor provided a competitive advantage on removing NO gas without any requirement of chelating chemicals.

Early diagnosis of cerebral aspergillosis with various methods: a case report.

The clinical and laboratory diagnosis of cerebral aspergillosis (CA) is problematic and mortality is quite high, even in cases receiving appropriate treatment. Therefore, an early and accurate diagnosis may prove to be life saving in patients with the diagnosis of CA. In this report, a case of CA which developed in a pediatric patient with acute lymphoblastic leukemia (ALL) is presented. Upon development of neutropenia and focal seizures in the left arm during implementation of the ALL treatment protocol, brain MRI was performed in the patient and nodular lesions compliant with brain abscess were detected in the frontal lobe, left cerebellum and the cingulate gyrus on the superior aspect of the left corpus callosum. Direct assessment of brain tissue revealed fungal elements, while consecutive serum galactomannan (GM) values were determined as 3.39 ng/ml and 0.72 ng/ml, and the consecutive serum (1x3)-beta-D-glucan (BG) values were 93 pg/ml and 356 pg/ml. Negative serum real-time polymerase chain reaction (RtPCR) and positive tissue RtPCR were determined, with growth of Aspergillus fumigatus in the culture. Treatment was initiated with amphotericin B and voriconazole; upon disappearance of symptoms and negative control serum BG and GM values, the patient was discharged with recommendations. In conclusion, this case is presented with the objective of indicating the significance of serological and molecular methods used in the early diagnosis of patients with CA.