Wastewater contains different kinds of contaminants, including antibiotics and bacterial isolates with human-generated antibiotic resistances. In industrialized countries most of the wastewater is processed in wastewater treatment plants which do not only include commercial wastewater, but also wastewater from hospitals. Three multiresistant pathogens—extended spectrum β-lactamase (ESBL)-harbouring Enterobacteriaceae (Gram negative bacilli), methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant Enterococci (VRE)—were chosen for screening in a state of the art wastewater treatment plant in Austria. Over an investigation period of six months all three multiresistant pathogens could be isolated from activated sludge. ESBL was the most common resistance mechanism, which was found in different species of Enterobacteriaceae, and in one Aeromonas spp. Sequencing of ESBL genes revealed the dominance of genes encoding members of CTX-M β-lactamases family and a gene encoding for PER-1 ESBL was detected for the first time in Austria. MRSA and VRE could be isolated sporadically, including one EMRSA-15 isolate. Whereas ESBL is well documented as a surface water contaminant, reports of MRSA and VRE are rare. The results of this study show that these three multiresistant phenotypes were present in activated sludge, as well as species and genes which were not reported before in the region. The ESBL-harbouring Gram negative bacilli were most common.

In a clinical setting it seems to be normal these days that a relevant proportion or even the majority of different bacterial species has already one or more acquired antibiotic resistances. Unfortunately, the overuse of antibiotics for livestock breeding and medicine has also altered the wild-type resistance profiles of many bacterial species in different environmental settings. As a matter of fact, getting in contact with resistant bacteria is no longer restricted to hospitals. Beside food and food production, the aquatic environment might also play an important role as reservoir and carrier. The aim of this study was the assessment of the resistance patterns of Escherichia coli and Klebsiella spp. out of surface water without prior enrichment and under non-selective culture conditions (for antibiotic resistance). In addition, the presence of clinically important extended spectrum beta lactamase (ESBL) and carbapenmase harboring Enterobacteriaceae should be investigated. During Joint Danube Survey 3 (2013), water samples were taken over the total course of the River Danube. Resistance testing was performed for 21 different antibiotics. Samples were additionally screened for ESBL or carbapenmase harboring Enterobacteriaceae. 39% of all isolated Escherichia coli and 15% of all Klebsiella spp. from the river Danube had at least one acquired resistance. Resistance was found against all tested antibiotics except tigecycline. Taking a look on the whole stretch of the River Danube the proportion of multiresistances did not differ significantly. In total, 35 ESBL harboring Enterobacteriaceae, 17 Escherichia coli, 13 Klebsiella pneumoniae and five Enterobacter spp. were isolated. One Klebsiella pneumoniae harboring NMD-1 carbapenmases and two Enterobacteriaceae with KPC-2 could be identified. Human generated antibiotic resistance is very common in E. coli and Klebsiella spp. in the River Danube. Even isolates with resistance patterns normally associated with intensive care units are present.

Antibiotic resistant bacteria (ARB) in the aquatic environment are reported from all over the world and their presence in the environment has become quite common. The current most prominent example is the presence of beta-lactamases harboring Enterobacteriaceae. The aim of this study was to investigate the presence and diversity (on the genetic and phenotypic levels) of extended spectrum beta-lactamases (ESBL) and carbapenemases harboring Enterobacteriaceae from the River Mur in the center of Graz, Austria's second largest city. Thus over a period of four months water samples were taken, filtrated and screened for these bacteria. All samples revealed ESBL harboring Enterobacteriaceae, of which all with only one exception were Escherichia coli. Dominant ESBL gene family was CTX-M, represented by subgroups CTX-M-1 group, CTX-M-2 group and CTX-M-9 group. Surprisingly co-resistances to non-beta-lactam antibiotics were low, only resistance to trimethoprim was detected in 50% of all (70) isolates. One Klebsiella oxytoca with GES-1 was isolated. To date, GES ESBL has never been reported from Austria before and only rarely from other European countries. Screening for carbapenemase harboring Enterobacteriaceae revealed one Enterobacter cloacae with the gene for VIM-1. Members sharing the same multi-locus-sequence-type (MLST) as well as members of the same rep PCR clusters occurred at different sampling time points. ESBL-harboring Enterobacteriaceae are common in Austrian river water, is dominated by Escherichia coli and CTX-M enzymes. Furthermore, some of the isolates could be linked to different origins.

Spread and persistence of antibiotic resistance pose a severe threat to human health, yet there is still lack of knowledge about reservoirs of antibiotic resistant bacteria in the environment. We took the opportunity of the Joint Danube Survey 3 (JDS3), the world's biggest river research expedition of its kind in 2013, to analyse samples originating from different sampling points along the whole length of the river. Due to its high clinical relevance, we concentrated on the characterization of Pseudomonas spp. and evaluated the resistance profiles of Pseudomonas spp. which were isolated from eight sampling points. In total, 520 Pseudomonas isolates were found, 344 (66.0%) isolates were identified as Pseudomonas putida, and 141 (27.1%) as Pseudomonas fluorescens, all other Pseudomonas species were represented by less than five isolates, among those two P. aeruginosa isolates. Thirty seven percent (37%) of all isolated Pseudomonas species showed resistance to at least one out of 10 tested antibiotics. The most common resistance was against meropenem (30.4%/158 isolates) piperacillin/tazobactam (10.6%/55 isolates) and ceftazidime (4.2%/22 isolates). 16 isolates (3.1%/16 isolates) were multi-resistant. For each tested antibiotic at least one resistant isolate could be detected. Sampling points from the upper stretch of the River Danube showed more resistant isolates than downriver. Our results suggest that antibiotic resistance can be acquired by and persists even in Pseudomonas species that are normally not in direct contact with humans. A possible scenario is that these bacteria provide a reservoir of antibiotic resistance genes that can spread to related human pathogens by horizontal gene transfer.

Cystic fibrosis (CF) is the most common hereditary lung disease in the Caucasian population, characterized by viscous bronchial secretion, consecutive defective mucociliary clearance, and unavoidable colonization with microorganisms. Besides Pseudomonas aeruginosa , Staphylococcus aureus is the most common bacterial species colonizing the CF respiratory tract. Under antibiotic pressure S. aureus is able to switch to small colony variants (SCV). These small colony variants can invade epithelial cells, overcome antibiotic therapy inside the cells and can be the starting point for extracellular recolonization. The aim of the present study was the isolation and characterization of S. aureus small colony variants from Austrian cystic fibrosis patients. Samples collected from 147 patients were screened for the presence of S. aureus wild-type and small colony variants. Antibiotic susceptibility testing and determination of the small colony variants causing auxotrophism were performed. Wild-type isolates were assigned to corresponding small colony variants with spa typing. In total, 17 different small colony variant isolates and 12 corresponding wild-type isolates were obtained. 13 isolates were determined thymidine auxotroph, 2 isolates were auxotroph for hemin, and none of the tested isolates was auxotroph for both, respectively. The presence of SCVs is directly related to a poor clinical outcome, therefore a monitoring of SCV prevalence is recommended. This study revealed rather low SCV ratios in CF patients compared to other countries.

Eosinophilic granulocytes (Eos) are found in great numbers both in the tissue and in the mucus of patients suffering from chronic rhinosinusitis with polyposis (ECRS). Interleukin-16 (IL-16) is known as a highly potent chemotactic and chemoattractant molecule (ED 10-11) for Eos. In an open, explorative, controlled study we examined the presence of IL-16 in mucosa tissue, mucus and serum in patients suffering from ECRS and its association to Eos activation. Tissue and nasal mucus specimen from 10 previously untreated, non allergic ECRS-patients undergoing paranasal sinus surgery and from 10 healthy non sinusitis subjects, undergoing nasal surgery because of anatomic nasal obstruction were investigated by real-time (RT-) PCR targeting human IL-16 mRNA. Haematoxylin-eosin (HE) staining and immunohistochemistry of formalin embedded tissue and mucus were applied for detection and determination of the proportion of activated Eos (aEos) and IL-16. Serum IL-16 was analyzed by enzyme-linked-immunosorbent assay (ELISA). IL-16 mRNA and IL-16 protein levels were elevated in nasal mucus, polyp tissue and in the serum of ECRS patients compared to healthy controls. There was a high proportion of aEos in ECRS patients compared to healthy subjects. Serum IL-16, IL-16 mRNA expression and IL-16 protein in mucus and tissue specimens were significantly associated with the presence of aEos in polyps of ECRS patients. Immunohistochemically IL-16 protein was mainly expressed in aEos, mast cells, lymphocytes and epithelial cells. In conclusion our data indicate that IL-16 may stimulate the migration and persistence of activated Eos in ECRS. IL-16 production in ECRS patients is not mediated by Immunglobuline-E (IgE).

Background: Umbilical cord blood (UCB) is a source of human hematopoietic precursor cells (HPCs), a stem cell (SC) type that has been used in several trials for myocardial repair. A certain minimal number of cells is required for measurable regeneration and a major challenge of SC-based regenerative therapy constitutes exvivo expansion of the primitive cell compartment. The aim of this study was to investigate the ex-vivo expansion potential of UCB-derived HPCs and the ability of these expanded cells to migrate to the site of damage and improve ventricular function in a rodent model of myocardial infarction (MI). Methods and Results:UCB-derived HPCs, defined by coexpression of CD133 and CD34, were expanded using various cytokine combinations. MI was induced by left anterior descending artery ligation in nude rats. Cells were injected intravenously 2 days after infarction. The combination of SC factor, thrombopoietin, flt3-ligand and interleukin-6 was found to be the most effective for inducing proliferation of HPCs. The migratory capacity of expanded HPCs was similar to that of non-expanded HPCs and improvement of ejection fraction was significant in both groups, with a relative increase of >60%.Conclusions: UCB-derived HPCs can be reproducibly expanded ex-vivo and retain their potential to improve cardiac function post-MI. (Circ J 2010; 74: 188 - 194)

Spa-typing and microarray techniques were used to study epidemiological changes in methicillin-resistant Staphylococcus aureus (MRSA) in South-East Austria. The population structure of 327 MRSA isolated between 2002 and 2012 was investigated. MRSA was assigned to 58 different spa types and 14 different MLST CC (multilocus sequence type clonal complexes); in particular, between 2007 and 2012, an increasing diversity in MRSA clones could be observed. The most abundant clonal complex was CC5. On the respective SCCmec cassettes, the CC5 isolates differed clearly within this decade and CC5/SCCmecI, the South German MRSA, predominant in 2002, was replaced by CC5/SCCmecII, the Rhine-Hesse MRSA in 2012. Whereas in many European countries MLST CC22-MRSA (EMRSA 15, the Barnim epidemic MRSA) is predominant, this clone occurred in Austria nearly 10 years later than in neighbouring countries. CC45, the Berlin EMRSA, epidemic in Germany, was only sporadically found in South-East Austria. The Irish ST8-MRSA-II represented by spa-type t190 was frequently found in 2002 and 2007, but disappeared in 2012. Our results demonstrate clonal replacement of MRSA clones within the last years in Austria. Ongoing surveillance is warranted for detection of changes within the MRSA population.