Investigation of antifungal susceptibility of Aspergillus species isolated from systemic clinical specimens by different methods.

PURPOSE: Due to the potential for Aspergillus species to cause lethal infections and the rising rates of antifungal resistance, the significance of antifungal susceptibility tests has increased. We aimed to assess the sensitivities of Aspergillus species to amphotericin B (AMB), voriconazole (VOR), itraconazole (ITZ), and caspofungin (CAS) using disk diffusion (DD) and gradient diffusion (GD) methods and compare them with broth microdilution (BMD) as the reference susceptibility method. METHODS: The study involved 62 Aspergillus fumigatus, 28 Aspergillus flavus, and 16 Aspergillus terreus isolates, totaling 106 Aspergillus isolates. BMD and DD methods were performed in accordance with CLSI M38-A2 and CLSI M51-A documents, respectively. The GD method utilized nonsupplemented Mueller Hinton agar (MHA) as the medium. RESULTS: In the BMD method, the lowest minimal inhibitory concentration (MIC)90 or minimal effective concentration (MEC)90 values were observed for VOR and CAS (0.5 µg/mL and 0.06 µg/mL, respectively). AMB and ITZ MIC90 values were both 2 µg/mL. In our comparison of the GD method with the BMD method at ±2 dilution, we observed essential agreement rates of 91.6%, 99.1%, 100%, and 38.6% for AMB, VOR, ITZ, and CAS, respectively. When comparing DD and BMD methods, we found categorical agreement rates of 65.1%, 99.1%, 77.3%, and 100% for AMB, VOR, ITZ, and CAS, respectively. For GD and BMD methods, these rates were 79.2%, 99.1%, 87.8%, and 100%. CONCLUSIONS: Given the high essential and categorical agreement rates, we posit that the GD method is a viable alternative to the BMD method for AMB, ITZ and VOR but not for CAS. In addition, the use of nonsupplemented MHA in the GD method proves advantageous due to its cost-effectiveness and widespread availability compared to other growth media.

Daily inpatient ertapenem therapy can be an alternative to hospitalization for the treatment of complicated urinary tract infections during the COVID-19 pandemic.

BACKGROUND: Physicians hospitalize the patients with complicated urinary tract infections (cUTIs) when they need intravenous antibiotics and outpatient parenteral antimicrobial therapy (OPAT) is unavailable. Daily inpatient antimicrobial therapy is an alternative to hospitalization, which is similar to OPAT; patients go home after they are administered antibiotics in a separate room in the hospital setting. OBJECTIVES: We assessed our previous daily inpatient practice to revitalize the model in the COVID-19 era. MATERIALS AND METHODS: We retrospectively evaluated the clinical and microbiological responses and the cost effectiveness of the patients with cUTIs who received daily inpatient ertapenem therapy. RESULTS: Our study population was 136 patients in 156 episodes. It was a difficult-to-treat group with older age (mean 63.0 ± 14.8 years) and a high burden of underlying conditions (86.5%). The most common causative organisms were Escherichia coli (74.4%) and Klebsiella pneumoniae (19.2%); 89.7% of the isolates were producing extended-spectrum beta lactamase (ESBL). The microbiologic and clinical success rates were 82.1% and 95.5%, respectively. The patients required hospitalization in 16 episodes (10.2%) because of clinical failures (3.8%), superinfections (2%), planned invasive interventions (3.2%), and side effects (1.2%). Our university hospital saved 1608 bed-days and 2596 € (9702 TL) bed costs. CONCLUSIONS: In the COVID-19 pandemic period, this seems to be an effective, safe, and cost-effective way to decrease hospitalizations for cUTIs in settings where OPAT is unavailable.

[Distribution of Yeast Species Isolated from Blood Cultures for a Six Year Period in Turkey: a Multicentre Study]. / Türkiye'de Alti Yillik Zaman Dilimi Içerisinde Kan Kültürlerinden Soyutlanan Maya Mantarlarinin Tür Dagilimi: Çok Merkezli Bir Çalisma.

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.

Investigation of mutations in Erg11 gene of fluconazole resistant Candida albicans isolates from Turkish hospitals.

Widespread use of fluconazole has resulted in resistance in strains of Candida. The aim of our study was to investigate Y132H and other mutations in the ERG11 gene in conferring fluconazole resistance to C. albicans isolates. Seven fluconazole-resistant (R)/susceptible dose-dependent (SDD)/trailing and 10 fluconazole-susceptible (S) isolates were included. Restriction enzyme analysis was performed on all isolates for Y132H mutation and sequence analysis was performed for other mutations in the ERG11 gene. None of our strains had Y132H mutation. One single mutation (D153E, E266D, D116E, V437I) was detected in isolates 348, 533, 644, 1453, 2157, while the others had more than one nucleotide change. D116E and E266D, which were two mutations found in fluconazole R/SDD/trailing isolates with the highest frequency, were also detected in azole S strains. K143R, G464S, G465S and V488I mutations were determined in three of the R/SDD isolates. S412T and R469K mutations were detected only in this group of strains by sequence analysis. Mutations such as K143R, G464S, G465S, V488I, S412T and R469K in the ERG11 gene were determined to be effective mechanisms in our fluconazole R/SDD C. albicans isolates. Other mechanisms of resistance, such as overexpression of ERG11 and efflux pumps and mutations in the ERG3 gene should also be investigated.

[Investigation of Aspergillus galactomannan levels in antimicrobial agents]. / Antimikrobiyal ilaçlarda Aspergillus galaktomannan düzeylerinin arastirilmasi.

The diagnosis of invasive aspergillosis which is a serious infection of immunocompromized patients, depends on the detection of Aspergillus galactomannan antigen in the serum by enzyme immunoassay (EIA) in routine laboratories. However, it has been previously reported that false positive results in Aspergillus galactomannan test may be obtained in the sera of patients sera receiving piperacillin-tazobactam (PIP-TAZ). The aim of this study was to investigate the presence and levels of Aspergillus galactomannan antigen in the content of PIP-TAZ and some other antimicrobial agents that are often used for the treatment of infections in immunocompromised patients. The level of galactomannan antigen was determined for PIP-TAZ, ampicillin-sulbactam, ampicillin, penicillin G, ceftriaxone, cefepime, imipenem, clarithromycin, ciprofloxacin, vancomycin, gentamicin, trimethoprim-sulfamethoxazole, ornidazole, fluconazole and amphotericin B, by a commercial EIA (Platelia Aspergillus EIA, Bio-Rad, France) kit. Galactomannan index (GI) was estimated with the ratio of absorbance values of antimicrobials to cut-off value and evaluated as positive when GI was found >0.5. Amongst the 15 antibiotics studied, the only positive result was detected for ampicillin with the highest index value (GI = 0.540), followed by PIP-TAZ with a relatively high value (GI = 0.235) even though it was not in the range of positivity. GI values have ranged from 0.011 to 0.188 for the other antibiotics. In conclusion, the use of especially ampicillin (and probably PIP-TAZ) therapy should be questioned in patients whose sera are being tested for Aspergillus galactomannan antigen by EIA in order to evaluate the positive results in terms of false positivities due to cross reactivity.

[Evaluation of species distribution of yeasts isolated from intensive care units during the four years period]. / Yogun bakim unitelerinden dört yillik dönemde izole edilen mayalarin tür dagiliminin degerlendirilmesi.

The aim of this study was to evaluate the distributions of yeast species according to the years and to detect the emerging pathogens in intensive care units (ICU). For this purpose, yeast isolation rates were detected retrospectively, in the following time periods: Period I: April-December 2001; period II: January-December 2002; period III: January-December 2003; period IV: January-December 2004. A total of 490 yeast isolates recovered from 462 clinical specimens obtained from 360 different ICU patients were investigated during these periods. Urine (62.1%), blood (13.6%) and tracheal aspirate (8.7%) samples were detected as the most common specimens. Of these isolates, 53.3% were identified as Candida albicans, 14.5% as C. tropicalis, 12.2% as C. glabrata, 6.5% as C. parapsilosis, 4.5% as Trichosporon spp., 3.9% as C. kefyr, 1.6% as C. krusei, 1.4% as Geotrichum candidum and 2.1% as other Candida species. The isolation rates of C. albicans in the periods of I to IV were found as 47.7%, 55.5%, 41.7% and 62.4%, respectively. The decrease between the second and third periods, and increase between third and fourth periods were statistically significant (chi2 = 4.15, p = 0.04 and chi2 = 8.32, p = 0.004). C. glabrata was the second most common species in the first and second periods (14.8% and 15.5%, respectively), followed by C. tropicalis (12.5% and 10.0%, respectively), however this array has changed in the third and fourth periods (C. tropicalis was the second with the rates of 16.7% and 16.8%, while C. glabrata placed in the third line with the rates of 14.8% and 7.6%, respectively). It was concluded that C. albicans has still been the most frequent species among yeast isolates of ICU's in our hospital; however, the incidence of non-albicans species like C. glabrata and C. tropicalis has increased.

[The importance of antinuclear (ABA) and anti-double stranded dna (anti-dsDNA) antibodies in the diagnosis of connective tissue diseases.]. / Konnektif doku hastaliklarinin tanisinda antinükleer (ANA) ve anti-double stranded dna (anti-dsDNA) antikorlarinin önemi.

Connective tissue diseases (CTD) are characterized by the presence of autoantibodies against several tissues. These autoantibodies occur against cell membrane, cell receptors, plasma proteins, and cytoplasmic and nuclear components. In laboratories, anti-nuclear antibodies (ANA) and anti-double stranded DNA (anti-dsDNA) antibodies are widely used in diagnosis of CTD. The aim of this study was to investigate the presence and accompaniment of ANA and anti-dsDNA antibodies in diagnosis of several CTD and also to study the prevalence of ANA and anti-dsDNA in a group of 88 patients with various types of CTD. ANA were detected by immunofluorescence (IFA) using HEp-2 cells (Zeus Scientific, Inc. USA) and anti-dsDNA antibodies using Crithidia luciliae (BioSystems, Spain) as substrates in immunofluorescence. ANA Western Blot (WB) Immunoassay (ImmuBlot, International Immuno-Diagnostics, USA) was also used along with the tests referred to previously. ANA was found in the sera of 84 (96.5%) patients while anti-dsDNA was detected in 7 (7.95%). Moreover different fluorescence patterns were also evaluated with ANA IFA in accordance with anti-dsDNA results. Mixed patterns in three and a homogeneous pattern in four anti-dsDNA positive patients' sera were determined on HEp-2 cell line by IFA. Seven sera which were ANA and anti-dsDNA positive with IFA were also found to be positive with WB and their ANA patterns with the specific ANA WB bands were also evaluated. It was observed that IFA results were in concordance with WB results. Our data indicated that the above findings should be controlled and evaluated with a more advanced method such as western blotting technique in order to confirm the presence of specific antibodies along with clinical outcome of the patients. As a result we think that ANA WB method is an appropriate technique in diagnosis of CTD as anti-dsDNA and ANA bands can be evaluated together with this method.

[Case report: a Fusarium fungaemia]. / Olgu raporu: bir Fusarium fungemisi.

In this report, a case of Fusarium fungaemia developed in an acute lymphoblastic leukemia (ALL) patient was presented. A seven year old girl who had weakness, loss of appetite, paleness and ecchymosis on legs applied to Pediatric Hematology Service and cytotoxic chemotherapy was started after she had been diagnosed as ALL-L1. Her chemotherapy was stopped because of increase in fever, leukopenia and neutropenia. Central venous catheter and peripheral blood cultures were obtained. Fusarium thapsinum was recovered from blood cultures, obtained in two consecutive days. Thereupon central venous catheter of the patient was removed and intravenous amphotericin B was added to the therapy. On the fifth day of febrile neutropenia attack, her fever was decreased after the onset of antifungal therapy. Radiological examinations were normal and no fungal growth was observed in the later blood cultures. On the 21st day of amphotericin B therapy, chemotherapy was started again and amphotericin B was changed to peroral itraconazole (200 mg/day) at the fifth week. The patient whose itraconazole therapy was stopped after three months, was still in remission and continued receiving her prolonged therapy. In conclusion, Fusarium infections which manifest with fungaemia and fever as the only symptoms, should be taken into consideration in neutropenic patients receiving immunosuppressive therapy.

[Comparison of indirect immunofluorescence and enzyme immunoassay methods for the determination of antinuclear antibodies]. / Antinükleer antikorlarin saptanmasinda indirek immünofloresan ve enzim immün yöntemlerinin karsilastirilmasi.

Antinuclear antibodies (ANA) are widely used for screening and monitoring of connective tissue diseases (CTD). Indirect immunofluorescence assay (IFA) is the standard method which is more often preferred for detecting these antibodies. Another method is enzyme immunoassay (ELISA) which includes extractable nuclear antigens (ENA). The aim of this study was to compare two different methods in view of their performances in the detection of ANA. A total of 27 sera from patients prediagnosed as different types of CTD, were screened by ANA-IFA (Zeus Scientific Inc, USA) and ELISA (Zeus Scientific Inc, ENA Profile-6, USA) methods. In addition, specific staining patterns of ANA on HEp-2 cells as a substrate, were enrolled with IFA. As a result, ANA positivity was detected in all of the 27 samples (100%) by IFA, and only in 7 (25.9%) by ELISA. The concordance rate between two different assays was estimated as 38.6%, and a statistically significant difference was found between the methods in the detection of ANA (x2=20, p<0.001). In conclusion, ANA-IFA method is still a reliable routine screening method for the laboratory diagnosis of CTD, while ENA Profile-6 ELISA may give false negative results, because of its limited antigen content, and should be supported with additional antigens.