Tadeja Matos

First recovery of Rasamsonia argillacea species complex isolated in adolescent patient with cystic fibrosis in Slovenia – case report and review of literature

We report the isolation of the emerging fungal pathogen Rasamsonia aegroticola, which belongs Rasamsonia argillacea species complex, from a respiratory sample of a patient with cystic fibrosis. This filamentous fungus, resembling members of a Penicillium and Paecilomyces spp., was identified by morphology and confirmed by DNA sequence analysis. Susceptibility pattern showed high minimal inhibitory concentration of voriconazole and amphotericin B but low minimal inhibitory concentration of caspofungin, micafungin and itraconazole.

Nocturnal Asthma and Domestic Exposure to Fungi

Fungal growth indoors is a common problem both in older and modern buildings. Numerous studies demonstrate a deterioration of asthma in environments with fungal growth but precise estimates of exposure levels have not been reported. This study was carried out to investigate whether levels of airborne fungi were higher in homes of subjects with nocturnal asthma as compared to controls. Subjects with nocturnal asthma (n = 42) and non-nocturnal asthma (n = 14) were recruited from an outpatient department. Subjects without disease or respiratory symptoms (n = 24) served as controls. Among the asthmatics, determinations were made of pulmonary function before and after treatment with bronchodilatators. The subjects were equipped with a pump and a filter and instructed to sample air in their bedroom. The filters were analysed for the content of N-acetylhexosaminidase (NAHA) as a marker of fungal cell biomass. In some houses the number of colony forming units was also determined. Patients with asthma had significantly higher activities of NAHA in their bedrooms as compared to controls (31.2 vs. 12.5 U m−3, p = 0.004). When the material was divided according to the 2nd quartile of NAHA (14.0 U m−3), 29 out of 42 subjects with nocturnal asthma had high values compared to 5 out of 24 for the controls (p<0.0001). The results support the hypothesis that patients with nocturnal asthma have high levels of fungi in their homes. This provides a basis for treatment and exposure diminution. Whether that exposure is causative for their disease; or if it aggravates already existing airway symptoms remains to be elucidated.

Subcutaneous infection with Pseudallescheria boydii in an immunocompromised patient

With the broad employment of immunosuppressive therapy, the incidence of Pseudallescheria boydii infections is rising. We report a first case of the localized subcutaneous P. boydii infection in a patient with microscopic polyangiitis. Favorable outcome related to the treatment with voriconazole adds to the growing body of evidence supporting the use of this particular agent in P. boydii infections.

Probiotic yeast Saccharomyces boulardii (nom. nud.) modulates adhesive properties of Candida glabrata

Following the widespread use of immunosuppressive therapy together with broad-spectrum antimycotic therapy, the frequency of mucosal and systemic infections caused by the pathogenic yeast Candida glabrata has increased in the past decades. Due to the resistance of C. glabrata to existing azole drugs, it is very important to look for new strategies helping the treatment of such fungal diseases. In this study, we investigated the effect of the probiotic yeast Saccharomyces boulardii (nom. nud.) on C. glabrata adhesion at different temperatures, pH values, and in the presence of fluconazole, itraconazole and amphotericin B. We also studied the adhesion of C. glabrata co-culture with Candida krusei, Saccharomyces cerevisiae, two bacterial probiotics Lactobacillus rhamnosus and Lactobacillus casei The method used to assess adhesion was crystal violet staining. Our results showed that despite the nonadhesiveness of S. boulardii cells, this probiotic significantly affected the adherence ability of C. glabrata This effect was highly dependent on C. glabrata strain and was either antagonistic or synergistic. Regarding the extrinsic factors, temperature did not indicate any significant influence on this S. boulardii modulatory effect, while at high pH and at increased concentrations of antimycotics, S. boulardii did not manage to repress the adhesion of C. glabrata strains. The experiments of C. glabrata co-cultures with other species showed that the adhesiveness of two separate cultures could not be used to predict the adhesiveness of their co-culture.

Organization of Patient Management and Fungal Epidemiology in Cystic Fibrosis

The achievement of a better life for cystic fibrosis (CF) patients is mainly caused by a better management and infection control over the last three decades. Herein, we want to summarize the cornerstones for an effective management of CF patients and to give an overview of the knowledge about the fungal epidemiology in this clinical context in Europe. Data from a retrospective analysis encompassing 66,616 samples from 3235 CF patients followed-up in 9 CF centers from different European countries are shown.

Characterization and fluorescence of yellow biofilms in karst caves, southwest Slovenia

Biofilms of different colours that colonize surfaces within karst caves represent a source of nutrients. They occur commonly and abundantly at sites with sediments, and close to seepages or underground rivers. Golden-yellow subaerial biofilms are particularly well observed because of their contrast with their surroundings, the characteristics of the pigment and recently, even more, due to the characteristics of light-emitting diode (LED) illumination. Yellow microbial biofilms were sampled from three caves in southwestern Slovenia, Dimnice, Križna jama and Sveta jama. The highest concentration of cultivable microbes (2.33×10 8 CFU/g) and the biggest number of identified bacteria (66.0%) were retrieved from a sample from Sveta jama. Using MALDI-TOF (Matrix-Assisted Laser Desorption/Ionization Time-Of-Flight) for bacterial identification showed that different species of Pseudomonas prevailed in all samples. Yellow biofilms showed an absorption peak around 400 nm, and two emission peaks, a major in the blue (~460 nm) and a minor in the orange (~600 nm) parts of the spectrum when excited at 405 nm. Microbial mats that colonize surfaces are probably frequently overlooked in caves because they are difficult to observe when they have no pigmentation and the contrast with their surroundings is low. Additional studies are needed to aid the understanding of the role of pigmented biofilms and their interactions with underlying substrata in respect of the evolution of substrate micromorphology.

First report of otitis externa caused by Schizophyllum commune and review of the literature.

SummaryBasidiomycete Schizophyllum commune is a widely distributed cellulolytic fungus that is a well-known pathogen. It can cause a wide range of different infections, and here we describe the first case of otitis externa and a molecularly based identification process.

Synergistic and antagonistic effects of immunomodulatory drugs on the action of antifungals against Candida glabrata and Saccharomyces cerevisiae

Candidemia and other forms of invasive fungal infections caused by Candida glabrata and to a lesser extent Saccharomyces cerevisiae are a serious health problem, especially if their steadily rising resistance to the limited range of antifungal drugs is taken into consideration. Various drug combinations are an attractive solution to the resistance problem, and some drug combinations are already common in the clinical environment due to the nature of diseases or therapies. We tested a few of the common antifungal-immunomodulatory drug combinations and evaluated their effect on selected strains of C. glabrata and S. cerevisiae. The combinations were performed using the checkerboard microdilution assay and interpreted using the Loewe additivity model and a model based on the Bliss independence criterion. A synergistic interaction was confirmed between calcineurin inhibitors (Fk506 and cyclosporine A) and antifungals (fluconazole, itraconazole, and amphotericin B). A new antagonistic interaction between mycophenolic acid (MPA) and azole antifungals was discovered in non-resistant strains. A possible mechanism that explains this is induction of the Cdr1 efflux pump by MPA in C. glabrata ATCC 2001. The Pdr1 regulatory cascade plays a role in overall resistance to fluconazole, but it is not essential for the antagonistic interaction. This was confirmed by the Cgpdr1Δ mutant still displaying the antagonistic interaction between the drugs, although at lower concentrations of fluconazole. This antagonism calls into question the use of simultaneous therapy with MPA and azoles in the clinical environment.

Microbiological diagnosis of invasive aspergillosis.

Background: Invasive aspergillosis is an important opportunistic fungal infection in highly immunocompromised patients. Clinical diagnosis of invasive aspergillosis remains difficult in that clinical signs and symptoms are nonspecific. Radiologic findings are not pathognomonic but can be suggestive. The isolation of aspergilli from a normally sterile environment, which lacks sensitivity, usually represents a problem. Blood cultures are of limited utility, because the recovery of Aspergillus species from blood cultures invariably represents contamination. Early diagnosis is critical to a medical treatment, but is difficult to achieve with current methods. Measurement of galactomannan and β-D-glucan can be used as an aid in the diagnosis of invasive aspergillosis and it might promote a favourable outcome. The use of polymerase-chain-reaction assay (PCR), although promising, is currently investigational. Conclusions: The verification of aspergillosis requires isolation and microscopic analysis of sterile material showing the fungal structures. Non-culture-based mycological tests, especially assays for the detection of Aspergillus galactomannan and β-D-glucan in serum, or Aspergillus galactomannan in BAL and cerebrospinal fluid specimens are fit to convey useful information and may enable a diagnosis of probable invasive aspergillosis. We may hope that PCR will be improved enough to overcome the limitations of current methods and be developed into a better diagnostic modality for this disease.

SENSITIVITY OF YEAST ISOLATED FROM SURVEILLANCE SPECIMENS INPATIENT WITH HAEMATOLOGICAL MALIGNANCIES IN YEAR 1992–2005

BACKGROUND Yeasts of the genus Candida are among the most frequent causative agents of opportunisticinfections. In the last decades, the increased incidence of fungal infections led to increasedconsumption of antifungal agents. Our study compared the sensitivity of Candidaalbicans and Candida glabrata isolated in two time periods 1992–1996 and 2003–2005.The aim of our study was to determine whether the sensitivity of yeasts changed due toincreased consumption of antifungal agents. METHODS All isolates were isolated from surveillance specimens of patients, hospitalized in the Departmentof Hematology, University Clinical Center Ljubljana. In all yeast isolates minimalinhibitory concentrations (MIC) of fluconazole, voriconazole, itraconazole and amphotericinB were determined using the E-test. Mann-Whitney’s U test was used for statisticalanalysis. RESULTS Statistical comparison generally indicated lower antifungal drug sensitivity of yeasts inyears 1992–1996, in comparison to the period 2003–2005. MICs of all tested antifungalagents in C. albicans isolates were higher in years 1992–1996. Differences in MICs ofitraconazole and voriconazole were observed in C. glabrata isolates. MICs of itraconazolewere higher in years 1992–1996 and MICs of voriconazole were higher in years 2003–2005. However, no statistically significant differences in MICs of fluconazole and amphotericinB were observed.We have also studied the influence of antifungal prophylactic therapy on MICs of antifungalagents. For C. albicans the influence was shown for fluconazole and amphotericin B,while we could not show any influence for C. glabrata, most probably due to low number ofisolates. CONCLUSIONS According to the results of our study, the hypothesis about decreased sensitivity of yeastsdue to increased consumption of antifungal agents in the last decades was rejected