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E Presterl

Publications and source records attributed to E Presterl.

At least 19 recordsLinked to original sources
PubMed2005

[Primary HIV-1 infection in Zurich: 2002-2004].

Acute HIV-infection mostly presents with unspecifc symptoms. Thus the acute retroviral syndrome is often not readily recognized. Here we present an interim analysis of a prospective study from 62 patients with documented acute HIV infection acquired between January 2002-August 2004 in the greater Zurich area. 61.5% of patients were infected by homosexual contacts, mostly with HIV-1 subtype B, 34% acquired infection by heterosexual contacts, often with non-B-virus subtypes. Transmission occurred in all sexually active age groups (18-72 years). Clinical symptoms presented as follows: fever (77%), pharyngitis (56%), fatigue (52%), gastrointestinal symptoms (45%), rash (39%). On first physician contact, an ARS was only suspected in 27% of the cases. Patients primarily called on their family doctors (37.5%), went to see larger walk in clinics or emergency rooms (37.5%), and 16% were hospitalised. In 16% of patients other sexually transmitted diseases were diagnosed contemporaneously. Drug resistant virus (single class resistance) was transmitted in only one patient.

Acute Disease↗
PubMed2005

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↗
PubMed2005

Clinical behavior of implant infections due to Staphylococcus epidermidis.

UNLABELLED: Surgical implants and other foreign material are increasingly used in modern medicine to restore or to improve the function of the human body. Infection of an implant is associated with considerable morbidity due to frequent hospitalizations, surgery and antimicrobial treatment. The underlying mechanism is the formation of a bacterial biofilm on the surface of the implanted body. The recognition and diagnosis of implant infections is essential for further therapy and, above all, the decision to remove and exchange the implant. METHODS: We compared the data of 60 patients with implant infections with those of 60 patients with transient bacteremia caused by Staphylococcus epidermidis. The pathogens isolated from blood were characterized with regard to antimicrobial susceptibility and formation of biofilms using a static microtiter plate model. Wild type skin isolates from non-hospitalized healthy volunteers served as control with regard to antimicrobial susceptibility and biofilm formation. RESULTS: Clinical signs and symptoms, underlying diseases and outcome were not different in either group. However, patients with implant infection had fever over a longer time (mean 12 days versus 3 days, respectively, p < 0.05) and more often positive blood cultures than patients with transient bacteremia (3.1 versus 1.2, p < 0.05). Thrombocytopenia was observed in patients with implant infections but not in patients with transient bacteremia (p < 0.05). Biofilms were formed in 86.4 % of the isolates in implant infection, in 88.8 % in transient bacteremia and in 76.9 % of the isolates from healthy volunteers (not significant). Multi-resistance to penicillin, oxacillin, erythromycin, clindamycin, ciprofloxacin and trimethoprim was more common in the hospital strains than in the wild type strains (75.6 % versus 48.7 %, p < 0.05). CONCLUSIONS: The clinical features of implant infections are indistinguishable from those of transient bacteremia. Persisting fever and multiple blood culture yielding the growth of skin flora bacteria are strong indicators for infection of implanted material. Biofilm formation and antimicrobial multi-resistance, as common in implant infection as in transient bacteremia, seem to be accessory factors in infections due to Staphylococcus epidermidis.

Adult↗
PubMed2004

Viridans streptococci in endocarditis and neutropenic sepsis: biofilm formation and effects of antibiotics.

OBJECTIVES: Viridans group streptococci (VGS) are a frequent cause of bacterial endocarditis or sepsis in patients with neutropenia. Endocarditis in particular, is associated with plaque formation on the endocardium and valve leaflets whereas VGS septicaemia in neutropenic patients is caused by the influx of oral flora bacteria through mucositic lesions. This study examined the in vitro potency for biofilm formation of clinical VGS bloodstream isolates, and the effects of antibiotics on these biofilms. METHODS: During the years 1998-2000, 40 VGS bloodstream isolates from 18 patients with endocarditis and 22 patients with severe sepsis and neutropenia were collected. The MICs of penicillin, teicoplanin and moxifloxacin were determined using the microdilution broth method according to NCCLS criteria. Biofilms were grown in microtitre plates, dyed with Crystal Violet, and the mean optical density (OD) was used for quantification. Biofilms were incubated with penicillin, teicoplanin and moxifloxacin at various concentrations starting with the MICs for the respective isolates tested. RESULTS: Isolates from eight out of 18 patients with endocarditis and six out of 22 patients with neutropenia formed biofilms (not significant). For the 14 isolates, the MIC(90)s (range) of penicillin, teicoplanin and moxifloxacin were 0.5 mg/L (0.001-0.5), 0.125 mg/L (0.025-0.125) and 0.5 mg/L (0.05-0.5), respectively. Generally, biofilms persisted although incubated with the antibiotics up to concentrations of 128 x MIC. However, the ODs of biofilms after incubation with an antibiotic were significantly lower than the ODs of biofilms without antibiotic (P<0.05). A significant decrease in the biofilms with increasing antibiotic concentrations was observed for teicoplanin and moxifloxacin, but not for penicillin G. CONCLUSIONS: VGS isolated from patients with endocarditis and patients with sepsis and neutropenia form biofilms. Biofilms persist even when exposed to antibiotics at concentrations up to 128 x MIC. Nevertheless, teicoplanin and moxifloxacin reduced the density of the biofilms at concentrations >/=16 x MIC. Thus, testing the effects of antibiotics on biofilms may supply useful information in addition to standard in vitro testing, particularly in diseases where biofilm formation is involved in the pathogenesis.

Adolescent↗
PubMed2001

Screening for possible failure of herpes simplex virus PCR in cerebrospinal fluid for the diagnosis of herpes simplex encephalitis.

The objectives of this study were to evaluate the reliability of herpes simplex virus (HSV) PCR testing in cerebrospinal fluid (CSF) for the detection of herpes simplex encephalitis. This was done by examining retrospectively the clinical follow-up of a large group of patients tested routinely by HSV-PCR. In addition, an attempt was made to assess the incidence of herpes simplex encephalitis in a central European population. CSF samples from 1,427 patients from all Vienna hospitals were submitted for HSV-PCR testing during a period of 4 years and 8 months. Herpes simplex encephalitis was detected by PCR in 12 cases and by serological methods in one additional patient. Retrospective analysis of the course of disease, which was possible in 799 PCR-negative patients, led to the identification of three additional cases in which herpes simplex encephalitis appears to have occurred despite negative PCR results. Failure of the PCR in these patients is most likely due to the time of obtaining CSF during the course of disease. A high specificity of the assay was demonstrated by the lack of false positive results in any of the 708 cases in which other causes for the neurological symptoms had been identified in the follow-up. The incidence of herpes simplex encephalitis in the population of Vienna was between 1 case/469,000-577,000 individuals/year. The highest annual incidence was detected in the age group between 3 months and 3 years, which, however, could not be confirmed statistically.

Adolescent↗
PubMed2001

Ciprofloxacin- and methicillin-resistant staphylococcus aureus susceptible to moxifloxacin, levofloxacin, teicoplanin, vancomycin and linezolid.

In order to determine the comparative efficacy of vancomycin, teicoplanin, levofloxacin, moxifloxacin, and linezolid against methicillin- and ciprofloxacin-resistant Staphylococcus aureus, each agent was tested against 65 genetically different strains using the microbroth dilution method. All of the isolates were typed using the enterobacterial repetitive intergenic consensus polymerase chain reaction to exclude multiple isolates of epidemic clones. Susceptibility testing revealed that all of the isolates were susceptible to vancomycin and teicoplanin. Linezolid exhibited minimum inhibitory concentration (MIC) levels ranging from 1 to 4 mg/l (MIC90, 4 mg/l). The MICs of moxifloxacin and levofloxacin ranged from 0.01 to 8 mg/l (MIC90, 8 mg/l) and 0.25 to 32 mg/l (MIC90. 16 mg/l), respectively. Thus, linezolid is active against methicillin- and ciprofloxacin-resistant Staphylococcus aureus, whereas moxifloxacin may need to be administered at a dose higher than recommended in order to successfully treat serious infections.

Acetamides↗
PubMed2001

Dysregulation of monocyte oxidative burst in streptococcal endocarditis.

BACKGROUND: Streptococcal subacute endocarditis is characterized by low-grade systemic inflammation. Although structural cardiac defects are pivotal, phagocytic cells, i.e. monocytes and neutrophils, are involved in the induction and the course of bacterial endocarditis. Decreased production of reactive oxygen metabolites was described in long-lasting infections. We hypothesized that the oxidative burst of phagocytes induced by the infecting organism is defective in patients with streptococcal endocarditis. PATIENTS AND METHODS: The monocytes and neutrophils of 11 patients with streptococcal native valve endocarditis were challenged with the respective pathogens and two control streptococcal strains, and the oxidative burst was determined by fluorescence-activated cell sorter analysis. These experiments were done before any antibiotic therapy was administered, and repeated at least 12 months after recovery. Eight volunteers served as healthy controls. RESULTS: The monocyte response to the respective pathogens was decreased in the patient groups compared to the response to the control streptococci. After cure the monocyte response to the pathogens was not different to the response to the control strains. The monocyte response of the healthy volunteers did not show any differences between the patients' pathogens and the control strains. The neutrophil oxidative burst to the pathogens was similar to that to the control streptococci in both patient and the volunteer group. CONCLUSION: The decreased response of patient monocytes to the pathogens may contribute to the low-grade inflammatory response and to the course of streptococcal endocarditis.

Adult↗
PubMed2001

Endocarditis by Lactobacillus rhamnosus due to yogurt ingestion?

A young man who ate large quantities of probiotic yogurt developed endocarditis and septic arthritis caused by Lactobacillus rhamnosus. The pathogenic isolate could not be distinguished from the yogurt microflora using methods routinely used in the clinical microbiology laboratory. Only by using more appropriate methodology, including PCR, the pathogen could be distinguished from the yogurt isolate.

Adult↗
PubMed2001

Antifungal susceptibility testing of fluconazole by flow cytometry correlates with clinical outcome.

Susceptibility testing of fungi by flow cytometry (also called fluorescence-activated cell sorting [FACS]) using vital staining with FUN-1 showed a good correlation with the standard M27-A procedure for assessing MICs. In this study we determined MICs for blood culture isolates from patients with candidemia by NCCLS M27-A and FACS methods and correlated the clinical outcome of these patients with in vitro antifungal resistance test results. A total of 24 patients with candidemia for whom one or more blood cultures were positive for a Candida sp. were included. Susceptibility testing was performed by NCCLS M27-A and FACS methods. The correlation of MICs (NCCLS M27-A and FACS) and clinical outcome was calculated. In 83% of the cases, the MICs of fluconazole determined by FACS were within 1 dilution of the MICs determined by the NCCLS M27-A method. For proposed susceptibility breakpoints, there was 100% agreement between the M27-A and FACS methods. In the FACS assay, a fluconazole MIC of <1 microg/ml was associated with cure (P < 0.001) whereas an MIC of > or =1 microg/ml was associated with death (P < 0.001). The M27-A-derived fluconazole MICs did not correlate with outcome (P = 1 and P = 0.133).

Adolescent↗
PubMed1999

Successful conservative treatment of severe renal candidosis with fungus balls.

Partial fungal obstruction of the renal collecting system is an unusual finding among infants that poses specific management problems. We report a patient with sepsis and fungal infection of the kidneys post surgery who presented with bilateral fungus balls and was successfully managed by conservative measures. Sonography is the imaging technique of choice in the diagnosis and follow-up of such patients. The need for prompt diagnosis in high-risk patients and the role of sonography are discussed.

Candidiasis↗
PubMed1999

Enteroaggregative and enterotoxigenic Escherichia coli among isolates from patients with diarrhea in Austria.

In a 3-month prospective study among 203 Austrian outpatients with diarrhea, the role of pathogenic Escherichia coli and the use of the polymerase chain reaction in screening Escherichia coli isolates from clinical stool specimens were evaluated. Enteroaggregative Escherichia coli and enterotoxigenic Escherichia coli combined were identified as the second most frequent cause of diarrhea. Of a total of 85 bacterial pathogens isolated from 80 patients, 15 were pathogenic Escherichia coli, 13 enteroaggregative Escherichia coli and two enterotoxigenic Escherichia coli. Enteropathogenic, enteroinvasive, and enterohemorrhagic Escherichia coli isolates were not detected.

Adolescent↗
PubMed1999

High serum laminin concentrations in patients with Candida sepsis.

BACKGROUND: Laminin, a major component of the basement membrane, plays a critical role in normal cell adhesion and also during tissue invasion of pathogenic microorganisms. MATERIALS AND METHODS: Serum laminin concentrations were determined in 19 patients with Candida albicans sepsis, in 13 patients with bacterial sepsis and in 20 noninfectious controls. RESULTS: Serum laminin concentrations of both, patients with candidal and bacterial sepsis, were significantly elevated compared to the controls (486 ng mL-1 [155-924], median [range]; P < 0.01). Laminin concentrations were significantly higher in patients with Candida sepsis than in patients with bacterial sepsis on day 1 (2565 ng mL-1 [659-6064] vs. 994 ng mL-1 [386-2064]; P < 0.01), day 7 (1594 ng mL-1 [607-4611] vs. 684 ng mL-1 [284-1920]; P < 0.05) and day 14 (1444 ng mL-1 [202-2131] vs. 386 ng mL-1 [180-1658]; P < 0.05). CONCLUSIONS: Laminin serum concentrations might be useful to differentiate nonbacterial, bacterial and fungal etiology.

APACHE↗
PubMed1999

Cytokines in sepsis due to Candida albicans and in bacterial sepsis.

Cytokines, such as tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and tumor necrosis factor-soluble receptor (TNF-sR), and adhesion molecules, e.g. vascular adhesion molecule-1 (VCAM-1) and E-selectin, play an important role in the pathogenesis of bacterial sepsis. Experimental data on cytokine expression during candidaemia are controversial. In this study, plasma concentrations of cytokines and adhesion molecules were compared between patients with sepsis due to Candida albicans and bacterial sepsis. Plasma levels of TNF-alpha, TNF-sR, IL-6, VCAM-1 and E-selectin, were determined in 20 patients with sepsis due to C. albicans, in 20 patients with bacterial sepsis, and in 20 controls on days 1, 7 and 14. On day 1, elevated plasma levels of TNF-alpha, TNF-sR and IL-6 were detected in both sepsis groups compared to controls. On day 1, VCAM-1 levels were higher, and E-selectin levels were lower in patients with Candida sepsis than in patients with bacterial sepsis (p < 0.05). At any time, VCAM-1 levels were significantly greater in patients with Candida sepsis than in patients with bacterial sepsis (p < 0.05). Non-survivors, regardless of the etiology of sepsis, had higher blood levels of IL-6, TNF-sR and E-selectin than survivors. The cytokines, TNF-alpha, IL-6 and TNF-sR, and the adhesion molecules, VCAM-1 and E-selectin, are involved in sepsis due to C. albicans as in bacterial sepsis.

Adolescent↗
PubMed1998

[New aspects in treatment of systemic mycoses].

The incidence of systemic fungal infection has been increasing during the last two decades. Candida and Aspergillus spp. are the classical opportunistic pathogens. Rare fungi, such as Mucor, Rhizopus, Fusarium, Trichosporon, Paecilomyces, Alternaria, Cladosporium and Pseudoallescheria, are emerging as cause of systemic fungal infection in the immunocompromised host. For more than 40 years Amphotericin B has been the gold standard of antifungal treatment because of its broad spectrum comprising yeasts, dimorphic fungi and moulds. Its nephrotoxicity has led to the development of lipid-associated preparations of amphotericin B: liposomal amphotericin B, amphotericin B colloidal dispersion and amphotericin B lipid complex. These preparations are less nephrotoxic, but higher doses than those of conventional amphotericin B are needed to achieve the same effect. The triazole fluconazole is the treatment of choice in infections caused by Candida albicans. New antifungal compounds are voriconazole and the candins, the pradimicin/benanomycin family, nikkomycin Z and a liposomal preparation of nystatin.

Amphotericin B↗
PubMed1998

Influence of glycopeptide antibiotics on purine metabolism of endothelial cells.

We provide evidence that the commercially available preparations of glycopeptides for intravenous application are well tolerated by endothelial cells when applied in concentrations less than 5 mg/ml. Since the antibiotics tested are administered at maximal concentrations of 10 mg/ml, the dose range used in our in vitro experiments (5 and 10 mg/ml) mimics possible clinical concentrations at the site of infusion. Similar concentrations may be reached by retrograde intravenous pressure infusion techniques (10-12). We have demonstrated that these high concentrations lead to considerable endothelial cell damage. These findings may explain the common side effect associated with intravenously applied glycopeptides namely pain and phlebitis at the site of infusion (2, 13). Figure 1 shows that a detrimental effect measurable after 20 min occurs only using vancomycin solutions at concentrations of 10 mg/ml, whereas already a dilution to 5 mg/ml renders the solutions more compatible to HUVEC. These data are in line with the observation that slow intravenous application of glycopeptides into large veins can largely prevent the occurrence of local phlebitis. Alternatively, the occurrence of phlebitis should be avoidable by diluting the manufacturers' preparations at least to 2-5 mg/ml and not 10 mg/ml as recommended by the manufacturer of vancomycin. The same aspects need to be considered for use of glycopeptides for retrograde high pressure infusion. The tolerance of intravenously applied antibiotics has previously been tested in animal models (4). Our model of human venous endothelial cells for testing antibiotic solutions for intravenous compatibility provides a valuable alternate model. In conclusion our data show that the commercial preparation of teicoplanin is more compatible for HUVEC than those of vancomycin.

Adenosine Triphosphate↗
PubMed1998

Helicobacter pylori urease significantly reduces opsonization by human complement.

The role of Helicobacter pylori urease in opsonization by human complement was investigated. H. pylori wild type strain N6 and isogenic mutants lacking either the large urease subunit (UreB) or an accessory urease protein (UreG) were incubated with different sera. C3b bound to the bacteria was measured by specific staining and flow cytometry. As compared with opsonization of N6 and the UreG-lacking mutant, opsonization of the UreB-lacking mutant was significantly increased after incubation with sera from both H. pylori uninfected (P<.001) or infected (P<.05) persons. However, when sera from uninfected persons were used, effective opsonization of this mutant proved to be dependent mainly on the classical pathway of complement activation. Irrespective of the serum used, opsonization values were very low after selective inactivation of the classical or the alternative pathway. Reduced opsonization of the urease-expressing strains could, to some extent, result from degradation of bound C3b.

Bacterial Proteins↗