Search PubMed⌕ Search

Biomedical subjects

C Lass-Flörl

Publications and source records attributed to C Lass-Flörl.

At least 19 recordsLinked to original sources

Characterization of methicillin-resistant Staphylococcus aureus from Ulaanbaatar, Mongolia.

In order to expand current knowledge of the types of methicillin-resistant Staphylococcus aureus (MRSA) strains circulating in central Asia, six MRSA strains collected from hospitals in Ulaanbaatar, Mongolia during 2000-2002 were examined. Three strains possessed a staphylococcal cassette chromosome mec (SCCmec) element of type IV c, were sequence type (ST) 154 according to multilocus sequence typing (MLST), and contained lukS-lukF (Panton-Valentine leukocidin). Another three strains contained a SCCmec element of type III and were MLST type ST 239. Using automated ribotyping, the six MRSA strains were divided into four different EcoRI ribotypes, and two groups of isolates were distinguished by means of SmaI-macrorestriction patterns. In comparison to other countries, the incidence of MRSA in Mongolia is low.

Anti-Bacterial Agents↗

Interaction of serotonin with Candida albicans selectively attenuates fungal virulence in vitro.

In this study we investigated whether the direct interaction between Candida albicans CBS 5982 and 5-hydroxytryptamine (5-HT) alters candidial virulence. Hyphae elongation, phospholipase activity and the production of secreted aspartyl proteinases (Saps) following 5-HT treatment were investigated. 5-HT treatment of C. albicans significantly (P < 0.05) affected hyphal extension, phospholipase activity and the production of Saps at concentrations of 118-0.46 mM. In conclusion, our findings suggest that the interaction between 5-HT and C. albicans may diminish the virulence properties of this fungal pathogen.

Aspartic Acid Endopeptidases↗

PCR based identification and discrimination of agents of mucormycosis and aspergillosis in paraffin wax embedded tissue.

BACKGROUND: Invasive fungal infections are often diagnosed by histopathology without identification of the causative fungi, which show significantly different antifungal susceptibilities. AIMS: To establish and evaluate a system of two seminested polymerase chain reaction (PCR) assays to identify and discriminate between agents of aspergillosis and mucormycosis in paraffin wax embedded tissue samples. METHODS: DNA of 52 blinded samples from five different centres was extracted and used as a template in two PCR assays targeting the mitochondrial aspergillosis DNA and the 18S ribosomal DNA of zygomycetes. RESULTS: Specific fungal DNA was identified in 27 of 44 samples in accordance with a histopathological diagnosis of zygomycosis or aspergillosis, respectively. Aspergillus fumigatus DNA was amplified from one specimen of zygomycosis (diagnosed by histopathology). In four of 16 PCR negative samples no human DNA was amplified, possibly as a result of the destruction of DNA before paraffin wax embedding. In addition, eight samples from clinically suspected fungal infections (without histopathological proof) were examined. The two PCR assays detected a concomitant infection with Absidia corymbifera and A fumigatus in one, and infections with Rhizopus arrhizus and A fumigatus in another two cases. CONCLUSIONS: The two seminested PCR assays described here can support a histopathological diagnosis of mucormycosis or aspergillosis, and can identify the infective agent, thereby optimising antifungal treatment.

Aspergillosis↗

[Epidemiology and prevention of pulmonary aspergillosis in patients with hematological malignancies].

Fungal pathogens are recognized as a major and increasing source of life-threatening infections in the immunocompromised host. Infections due to Aspergillus species are among the most common causes of nosocomial pneumonia in patients with hematological malignancies and are associated with an extremely high mortality rate. Aspergillus infections are often related to new building construction and reconstruction, road work, contaminated air conditioning systems,and contaminated potting soils. Endogenic sources include asymptomatic colonization of the respiratory tract and pulmonary aspergilloma. Suitable measures in the patient's environment to protect him from exposure to fungal spores may result in a marked reduction of infection risk. The use of high-efficiency particulate air (HEPA) filtration systems during hospitalization represents the current standard in prevention of invasive pulmonary aspergillosis. This article addresses epidemiological aspects, exposure factors, and preventive aspects with special attention to construction work in hospitals.

Aspergillosis↗

Chronic paracoccidioidomycosis in a female patient in Austria.

Presented here is a case of chronic paracoccidioidomycosis that occurred in a Cuban female living in Austria and was first misdiagnosed as tuberculosis. The clinical picture was one of progressive pulmonary insufficiency with fever, weight loss and productive cough. Since antituberculous therapy was started but did not achieve a long-term clinical response, an intensive diagnostic work-up was performed. Paracoccidioides brasiliensis was then diagnosed by histopathology, serology, microbiology and molecular identification. Antifungal therapy was commenced immediately with amphotericin B (1 mg/kg/day) for 10 days, followed by voriconazole (200 mg/day po) for at least 3 months, and the lesions disappeared almost completely. This report presents the first published case of imported paracoccidioidomycosis in a female patient in Austria.

Adult↗

Serotonin (5-HT) enhances the activity of amphotericin B against Aspergillus fumigatus in vitro.

We investigated the in vitro synergistic antifungal potential of combining serotonin (5-HT) and sertraline with amphotericin B and itraconazole against clinical isolates of Aspergillus spp. Synergy tests were performed using the chequerboard microdilution method. Activity was measured against Aspergillus fumigatus (n = 7), Aspergillus flavus (n = 3) and Aspergillus terreus (n = 2), and compared with that for Candida albicans and Candida parapsilosis. The fractional inhibitory concentration (FIC) indices ranged between 0.25 and 3 for the various isolates tested. 5-HT was shown to enhance the activity of amphotericin B against Aspergillus spp. Combination studies with 5-HT and itraconazole and with sertraline and itraconazole or amphothericin B showed different activities for the various strains, including synergism (FIC < 1.0), additivity (FIC = 1), and indifference (FIC between 1.0 and 2.0). 5-HT and sertraline showed antagonistic activity (FIC > 2) with amphotericin B and itraconazole against C. parapsilosis.

Amphotericin B↗

Fungal colonization in neutropenic patients: a randomized study comparing itraconazole solution and amphotericin B solution.

We assessed the impact of prophylaxis with the oral itraconazole solution and amphotericin B solution on fungal colonization and infection in a randomized study among patients with hematological malignancies and neutropenia. Infecting and colonizing Candida strains of patients suffering from candidiasis were genotyped by random amplification of polymorphic DNA (RAPD) analysis. A total of 106 patients were evaluated in this study: 52 patients in the itraconazole and 54 in the amphotericin B arm. During neutropenia fungal colonization in the oropharynx occurred in 11 (19.6%) and 24 (40.6%) and in the rectum in 11 (19.6%) and 23 (38.9%) courses in the itraconazole and amphotericin B groups ( P<0.05), respectively. Candida albicans was the most prevalent species in both study groups. Mixed fungal colonization with Candida krusei and Candida glabrata was increased in the amphotericin B group, yet without clinical importance since infections were due to C. albicans. The occurrence of invasive candidiasis was significantly increased in multicolonized compared to monocolonized patients. In the amphotericin B group 20 and in the itraconazole group 2 neutropenic patients showed multicolonization with Candida spp. ( P<0.05). Overall fungal infections were 3.8% in the itraconazole and 14.8% in the amphotericin B group ( P<0.05). RAPD typing showed oropharynx strains involved in superficial infections in four of five patients. In all four patients with deep fungal infections, it appears that the colonizing rectum strains were identical to infecting strains of Candida spp. Itraconazole solution significantly reduced Candida colonization and infection compared to amphotericin B solution. Most patients remained infected with the colonized strains for the entire study period, irrespective of antifungal prophylaxis.

Amphotericin B↗

Contamination during removal of cement in revision hip arthroplasty. A cadaver study using ultrasound and high-speed cutters.

Instruments used in surgery which rotate or vibrate at a high frequency can produce potentially contaminated aerosols. Such tools are in use in cemented hip revision arthroplasties. We aimed to measure the extent of the environmental and body contamination caused by an ultrasound device and a high-speed cutter. On a human cadaver we carried out a complete surgical procedure including draping and simulated blood flow contaminated with Staphylococcus aureus (ATCC 12600). After cemented total hip arthroplasty, we undertook repeated extractions of cement using either an ultrasound device or a high-speed cutter. Surveillance cultures detected any environmental and body contamination of the surgical team. Environmental contamination was present in an area of 6 x 8 m for both devices. The concentration of contamination was lower for the ultrasound device. Both the ultrasound and the high-speed cutter contaminated all members of the surgical team. The devices tested produced aerosols which covered the whole operating theatre and all personnel present during the procedure. In contaminated and infected patients, infectious agents may be present in these aerosols. We therefore recommend the introduction of effective measures to control infection and thorough disinfection of the operating theatre after such procedures.

Aerosols↗

Environmental and body contamination through aerosols produced by high-speed cutters in lumbar spine surgery.

STUDY DESIGN: A cadaver study to evaluate contamination in the operating room through the use of a high-speed bone cutter. OBJECTIVES: To determine the grade of contamination of animate and inanimate objects through an aerosol intraoperatively, produced by a high-speed cutter during lumbar laminectomy. SUMMARY OF BACKGROUND: In spinal surgery, high-speed cutters are used that produce an aerosol consisting of a mixture of irrigation solution, blood, and tissue debris. Such aerosols can be contaminated with potential pathogens. The surgical personnel and the environment are therefore exposed to a contamination risk. METHODS: Laminectomies at three points (L2-L4) were performed on a human cadaver using a high-speed cutting device. The aerosol produced by the irrigation solution was contaminated with Staphylococcus aureus ATCC 12600. To detect the contamination of the environment and of the surgical team, surveillance cultures were used. RESULTS: By air sampling, staphylococci were detected in the operating room at an extension of 5 by 7 m. The surgical team showed extensive face and body contamination with S. aureus. Despite protection by a barrier drape, similar contamination was observed on both the cadaver's head and the anesthesiologist. CONCLUSIONS: The use of high-speed cutters in spinal surgery produces an aerosol that can be contaminated with blood-borne pathogens from infected patients. This aerosol is spread over the whole surgical room and contaminates the room and all personnel present. It is therefore critical to ensure that effective infection control measures are performed, not only by the surgeons but by everyone present in the operating room. The room itself must be sufficiently disinfected after such procedures.

Aerosols↗

Increased serum amylase and lipase in fructose malabsorbers.

BACKGROUND: Fructose malabsorption is frequently seen in the general population and is characterised by the inability to absorb fructose efficiently. Due to fructose malabsorption, fructose reaches the colon where it is broken down by bacteria to short fatty acids, CO(2) and H(2). Bloating, cramps, osmotic diarrhea and other symptoms of irritable bowel syndrome are the consequence. We recently found that fructose malabsorption is associated with low plasma folic acid concentrations and low serum tryptophan and zinc. Because fructose malabsorption apparently is associated not only with malabsorption of other nutrients, but also with abdominal discomfort, it was of interest to examine whether mild pancreatitis may be involved. METHODS: We retrospectively examined our data in 159 otherwise healthy adults (110 females, 49 males) aged 14-84 years (mean 45.6+/-14.4 S.D.) with gastrointestinal complaints for serum amylase and serum lipase concentrations. The patients have been tested earlier for fructose malabsorption and lactose maldigestion by measuring breath H(2) concentrations after an oral dose of 25 g fructose and 50 g lactose, respectively, 1 week apart. RESULTS: Fructose malabsorption (H(2) concentrations > or =20 ppm over baseline values) was detected in 107 of 159 individuals (67.3%). These subjects with fructose malabsorption presented with significantly higher serum amylase concentrations (73.1 U/l+/-25.7 S.D.) compared to individuals with normal fructose absorption (59.6 U/l+17.9 S.D; p=0.0009). Fructose malabsorbers also presented with higher serum lipase concentrations (122.0 U/l+/-100.3 S.D.) compared to normals (89.5 U/l+/-46.5 S.D.; p<0.05). To determine whether this finding is a consequence of any sort of malabsorption syndrome or whether it is specific for fructose malabsorption, all subjects were screened for lactose maldigestion. Lactose maldigestion (H(2) concentrations>20 ppm over baseline after lactose loading) was found in 50 of 159 individuals (31.4%). There were no significant differences in either amylase or lipase concentrations in lactose maldigestors. CONCLUSION: Serum amylase and lipase concentrations are higher in subjects with fructose malabsorption compared to normals. Therefore, fructose malabsorption should be considered as a differential diagnosis in moderately elevated serum amylase.

Adolescent↗

Candida ciferrii, a new fluconazole-resistant yeast causing systemic mycosis in immunocompromised patients.

Systemic infections related to fluconazole-resistant yeasts are increasingly observed in immunocompromised patients receiving fluconazole as a prophylactic antifungal treatment. Here, we report a case of invasive candidiasis caused by Candida ciferrii in a patient with acute myeloid leukemia and who suffered a relapse after autologous peripheral blood progenitor cell transplantation. Erythematous skin papulae and spotted pulmonary infiltrations were present. A skin biopsy led to the diagnosis of invasive candidiasis, emphasizing the diagnostic usefulness of this procedure. The yeast was identified as Candida ciferrii and in vitro susceptibility testing revealed its resistance to fluconazole. Until now, Candida ciferrii has not been known to cause invasive fungal infections in humans. Thus, we add another fungus to the list of flucanozole-resistant yeasts and suggest that in vitro susceptibility testing of isolated fungi should be performed for the selection of appropriate antimycotic drugs.

Antifungal Agents↗

Aerosols produced by high-speed cutters in cervical spine surgery: extent of environmental contamination.

High-speed cutters are used in the surgery of the cervical spine. Such high-speed devices can produce an aerosol cloud. As a patient can be a reservoir for pathogens, with aerosol-borne paths of transmission, such an aerosol has to be seen as a potential risk of infection for health care professionals present during the surgery and for patients if micro-organisms are transferred through the medical personnel. The study was performed in order to measure the extension of environmental and body contamination through contaminated aerosols produced by a high-speed cutter. Three laminectomies (C4-C6) were performed on an intact human cadaver with a high-speed 0.6-mm ball cutter. A complete surgical setup was arranged, including surgical draping and a barrier drape to the anesthesiologist's workplace. Body and environmental contamination was detected by the use of surveillance cultures. The irrigation solution was artificially contaminated with Staphylococcus aureus ATCC 12600. Following the surgery, staphylococci were detected in the operating room at an extension of 5x7 m. Everybody showed extensive face and body contamination with Staphylococcus aureus. The study showed that the use of high-speed cutters in surgery of the cervical spine produces an aerosol cloud that is spread over the whole surgical room and contaminates the theater and all personnel present. Such aerosols can be contaminated with pathogens if the patient was infected or colonized. Therefore, sufficient protective measures have to be recommended for everyone present in the operating room during such surgeries. In addition, efficient disinfection of the room and all mobile equipment is necessary after each surgery involving high-speed cutting devices.

Aerosols↗

Screening for Aspergillus spp. using polymerase chain reaction of whole blood samples from patients with haematological malignancies.

Sensitive screening for Aspergillus spp. using polymerase chain reaction (PCR) of whole blood samples in patients with haematological disorders has not been performed to date. In a 2-year study, 121 patients admitted to the University Hospital of Innsbruck for cancer chemotherapy without clinical signs of fungal infection were prospectively screened for Aspergillus spp. In 28 out of 121 (23%) patients, Aspergillus DNAaemia was detected. Of these patients, 16 (57%) were positive only once for Aspergillus DNA, but positivity was never associated with invasive aspergillosis. PCR positive episodes were short and resolved without antifungal treatment. Five patients (18%) had intermittent PCR positive results. Seven (25%) patients presented at least two consecutive positive PCR results; one of these patients developed invasive aspergillosis and another two were strongly suspected as having aspergillosis. Based on the criteria of the European Organization for Research and Treatment of Cancer case definitions, sensitivity and specificity of serial PCR monitoring were 75% and 96%. Positive PCR results became negative shortly after commencement of antifungal treatment, but the changes did not correlate with clinical responsiveness to treatment in three patients. Our results indicate the potential usefulness of PCR for screening for Aspergillus spp. in patients at risk, but without antifungal treatment.

Adult↗

Human immunodeficiency virus type 1 Tat binds to Candida albicans, inducing hyphae but augmenting phagocytosis in vitro.

Tat, the human immunodeficiency virus type 1 (HIV-1) transactivating protein, binds through its RGD-motif to human integrin receptors. Candida albicans, the commonest cause of mucosal candidiasis in subjects infected with HIV-1, also possesses RGD-binding capacity. The present study reveals that Tat binds to C. albicans but not to C. tropicalis. Tat binding was markedly reduced by laminin and to a lesser extent by a complement C3 peptide containing the RGD motif, but not by a control peptide. The outgrowth of C. albicans was accelerated following binding of Tat, but phagocytosis of opsonized C. albicans was also increased after Tat binding. Thus, Tat binding promotes fungal virulence by inducing hyphae but may also reduce it by augmenting phagocytosis. The net effect of Tat in vivo is difficult to judge but in view of the many disease-promoting effects of Tat we propose that accelerating the formation of hyphae dominates over the augmentation of phagocytosis.

ATPases Associated with Diverse Cellular Activitie↗

Enhanced fungicidal activity of N-chlorotaurine in nasal secretion.

The antifungal activity of N-chlorotaurine (NCT), a long-lived oxidant produced by stimulated human leucocytes, was investigated. Incubation of Aspergillus spp., Candida spp., Fusarium spp., Penicillium spp. and Alternaria spp. in 1% NCT (55 mM) for 1-4 h produced a log10 reduction in cfu of between 1 and 4. In samples of nasal secretion, killing was significantly hastened (30 min), which may be explained by the formation of monochloramine by halogenation of ammonium, which was found at a concentration of 1 mM in these samples. For these reasons, NCT is of interest as a new agent for treatment of local inflammatory mycosis, e.g. eosinophilic fungal rhinosinusitis.

Antifungal Agents↗

Antifungal properties of selective serotonin reuptake inhibitors against Aspergillus species in vitro.

This study investigated the fungicidal activity of selective serotonin reuptake inhibitors (SSRIs) against clinical isolates of Aspergillus fumigatus (n = 11), Aspergillus flavus (n = 9), Aspergillus terreus (n = 10) and Candida parapsilosis (ATCC 22019). The common drugs fluoxetine, seroxate, sertraline, paroxetine and reboxetine were applied in a broth microdilution test. In addition, we examined whether a post-antibiotic effect occurs following short exposure to the drugs. The various SSRIs showed time- and dose-dependent effects and were fungicidal towards the organisms tested. Sertraline and fluoxetine were the most active drugs, yet there were differences in the susceptibility of the various isolates tested. A lag of regrowth was dependent on the various SSRIs tested and their concentration. Treatment for 4 h at concentrations of sertraline below and equipotent to the minimal fungicidal concentration resulted in a lag of regrowth of 8-24 h for isolates of A. fumigatus and A. flavus. In conclusion, our in vitro studies clearly demonstrate antifungal effects of SSRIs. Animal studies are needed to evaluate the potential role of these psychotropic drugs in the management of fungal infections.

Antifungal Agents↗

Contamination risk of the surgical team through ROBODOC's high-speed cutter.

During cutting of the femoral cavity in the ROBODOC procedure, an aerosol cloud of irrigation fluid, blood, and tissue debris was seen. This cloud potentially is contaminated with bacterial and viral vectors, which is an infection risk for the surgical team. A flat and a ball cutter were tested in four standard situations macroscopically with a colored solution. In a second experiment, the cutter was exposed to a fluid contaminated with Staphylococcus aureus, and bacterial room contamination was detected using standard cultures. The aerosol cloud was seen in a 6 x 3.6-m area. Extension and concentration varied, depending on the irrigation situation. ROBODOC's high-speed cutter produces an aerosol cloud in an area in which all members of the surgical team are affected. Sufficient protection is necessary for everyone in the operating room.

Equipment Contamination↗