ATR-FTIR Spectroscopy Highlights the Problem of Distinguishing Between Exophiala dermatitidis and E-phaeomuriformis Using MALDI-TOF MS

WOS: 000369061400008PubMed ID: 26373644The present study compared two chemical-based methods, namely, matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) and attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, to understand the misidentification of Exophiala dermatitidis and Exophiala phaeomuriformis. The study utilized 44 E. dermatitidis and 26 E. phaeomuriformis strains, which were partially treated with strong acids and bases for further evaluation. MALDI-TOF MS and ATR-FTIR spectroscopy data of the two Exophiala species were compared. Data groupings were observed for the chromic acid- and nitric acid-treated species when the black yeast sources were categorized as creosoted-oak sleepers, concrete sleepers, or dishwasher isolates. The MALDI-TOF MS data for the metalloenzyme-containing regions were consistent with the ATR-FTIR spectroscopy data. These results indicated that environmental isolates might contain metals not found in human isolates and might interfere with chemical-based identification methods. Therefore, MALDI-TOF MS reference libraries should be created for clinical strains and should exclude petroleum-associated environmental isolates

Evaluation of Blood Culture Practices: Use of System (Epicenter) Data

Sepsis is a serious clinical problem and estimated to be responsible for 18 million annual deaths worldwide. Therefore, the use and the rapid processing of blood cultures are important for the transition from empiric therapy to directed therapy. The aim of this study was to assess the best blood culture practices in Turkey. We have examined the collection practices and techniques at four different hospitals, and a total of 165.443 blood culture bottles were evaluated (2013-2015). At the preanalytical phase most of the data which were important and which could support hospital quality systems/practices were not entered into the HIS and EpiCenter system. At the analytical phase loading of the bottles and removal of positive bottles primarily occurred between 6:00 and 9:00 AM but the positivity rate of the bottles showed a homogeneous distribution throughout the day. In other words, there were significant delays at processing positive blood culture bottles related to laboratory workers. The effect of education regarding best practices, transition from single bottle to two bottle cultures was successful in all hospitals. Single bottle usage decreased below 10% in all hospitals. Significantly more positive cultures were detected at multiple cultures when compared with the single bottle collection practice. In retrospective patient records, it was seen that all the laboratories reported the results of Gram staining to the clinics. However, these data were not recorded to the Epicenter. The contamination rates of Ankara Numune Hospital and Akdeniz University Faculty of Medicine Hospital are 6.2% and 5.4% respectively, contamination rates were not reported in other hospitals. The most common isolates detected in blood cultures were Escherichia coli, Klebsiella pneumoniae, Enterococcus faecium, Staphylococcus aureus, and Acinetobacter baumannii. The mean time for the detection of these organisms were less than 20 hours in the aerobic bottle and anaerobic bottles. A total of 79.6% of facultative anaerobic isolates were detected in both bottles; 9.8% were detected only in the aerobic bottles; 10.6% of the isolates were detected only in the anaerobic bottles. As a result, the educational efforts in Turkey have met with success for transition from collecting single bottle blood culture sets to two bottle blood cultures. However, further efforts are needed to increase the number of blood culture sets collected during a 24 hour's period. In addition, errors at the preanalytical, analytical and postanalytical periods (taking samples, loading bottles into the system and processing positive blood cultures) should be eliminated.C1 [Basustaoglu, Ahmet] Baskent Univ, Dept Med Microbiol, Fac Med, TR-06790 Ankara, Turkey.[Suzuk Yildiz, Serap] MoH Gen Directorate Publ Hlth, Dept Microbiol Reference Lab & Biol Prod, Ankara, Turkey.[Mumcuoglu, Ipek; Kursun, Senol] Ankara Numune Training & Res Hosp, Lab Med Microbiol, Ankara, Turkey.[Karahan, Zeynep Ceren; Evren, Ebru] Ankara Univ, Dept Med Microbiol, Fac Med, Ankara, Turkey.[Ogunc, Dilara; Ozhak Baysal, Betil] Akdeniz Univ, Dept Med Microbiol, Fac Med, Antalya, Turkey.[Kaleli, Ilknur; Demir, Melek] Pamukkale Univ, Dept Microbiol, Fac Med, Denizli, Turkey.[Murray, Patrick] BD Diagnost Syst, Hunt Valley, MD USA

Epidemiology of pertussis in adolescents and adults in Turkey

Two hundred and fourteen patients who had a cough illness lasting at least 2 weeks were studied to investigate Bordetella pertussis as a cause of prolonged cough in adolescents and adults. Medical history and nasopharyngeal swab specimens for culture and polymerase chain reaction (PCR) were obtained at presentation. Three (1.4%) patients were B. pertussis culture-positive; 15 (7%) were B. pertussis PCR-positive (including the culture-positive patients) and 11 (5.1%) were Bordetella spp. PCR-positive. Symptom combinations were significantly high both in patients with pertussis and patients with indeterminate results (P < 0.05). We conclude that B. pertussis should be considered among differential diagnoses of prolonged cough in adolescents and adults and PCR and culture should be used to detect these cases and facilitate public health response