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Neben Akutkliniken sind auch Rehabilitationskliniken zunehmend von der Problematik der multiresistenten Erreger betroffen. Lange Verweildauern und hohe Behandlungsintensitaten stellen dabei besondere Herausforderungen an die Hygiene dar. Systematische Untersuchung eines Ausbruchs mit „Extended Spectrum Beta-Lactamasen“-Klebsiella-pneumoniae (ESBL-K. pneumoniae) in einer Neurorehabilitationsklinik. Gesicherter Fall: Patient mit einem ESBL-K.-pneumoniae-Nachweis im Ausbruchszeitraum und Zugehorigkeit zum Ausbruchsklon, wahrscheinlicher Fall: kein typisiertes Isolat, aber epidemiologischer Link zum Ausbruchsgeschehen. Insgesamt 53 ESBL-K.-pneumoniae-Isolate wurden mittels Next Generation Sequencing (NGS) typisiert. Umgebungsuntersuchungen wurden durchgefuhrt und ein systematisches Screening wurde implementiert. Neben einer Starkung der Standardhygiene wurde eine Kohortierung von Patienten mit ESBL-K.-pneumoniae veranlasst. Insgesamt wurden 30 gesicherte und 6 wahrscheinliche Falle dem Ausbruchsgeschehen zugeordnet (Cluster 1, ST15). In der Typisierung konnten 2 weitere Cluster identifiziert werden: Cluster 2 (ST405) bei 7 Patienten und Cluster 3 (ST414) bei 8 Patienten. Bei 2 Patienten entwickelte der Ausbruchsstamm ST15 weitere Antibiotikaresistenzen (Colistin bzw. Carbapenem). ESBL-K.-pneumoniae wurde in Umgebungsuntersuchungen nicht identifiziert. Der Ausbruch konnte nach strikter Kohortierung beendet werden. Die Erregerausbreitung erfolgte vermutlich von Mensch zu Mensch. Die Ubertragungswahrscheinlichkeit stieg mit dem Grad der Interventionsintensitat, wahrend die Infektionsrate durch die Morbiditat der Patienten bedingt war. Die Identifikation eines Ausbruchsklons mit Entwicklung zusatzlicher Antibiotikaresistenzen und die Entdeckung weiterer Cluster demonstrieren die Relevanz einer Erregertypisierung und eines effektiven Ausbruchsmanagements.

In addition to acute care hospitals, rehabilitation centres are increasingly confronted with multi-resistant pathogens. Long durations of stay and intensive treatments impose special hygienic challenges.We investigated an extended spectrum beta-lactamase-Klebsiella pneumoniae (ESBL-K. pneumoniae) outbreak in a neurorehabilitation centre. We defined confirmed cases as patients who stayed in the centre during the outbreak period and from whom ESBL-K. pneumoniae was isolated with the outbreak sequence type. Probable cases had an epidemiological link to at least one confirmed case but no isolate for typing. Next generation sequencing (NGS) was performed on 53 isolates from patients. Environmental sampling was performed. Systematic microbiological screening was implemented and ESBL-K. pneumoniae-positive patients were cohorted in a designated ward.We identified 30 confirmed and 6 probable cases. NGS revealed three genetic clusters: Cluster 1 - the outbreak cluster - with isolates of 30 cases (sequence type ST15), Cluster 2 with 7 patients (ST405) and Cluster 3 with 8 patients (ST414). In two patients, the outbreak strain developed further antibiotic resistance, one with colistin resistance and the other carbapenem resistance. The outbreak ceased after strict isolation measures.Epidemiology and NGS results paired with the effectiveness of cohorting suggest that transmission occurred mainly from person to person in this outbreak. There was an apparent association of the probability to acquire ESBL-K. pneumoniae and treatment intensity, whereas infection rate was related to morbidity. The identification of the outbreak clone and additional clusters plus the development of additional antibiotic resistance shows the relevance of NGS and highlights the need for timely and efficient outbreak management.

Background: Routine urine culture testing is not recommended for uncomplicated urinary tract infections (UTIs). As a result, the antibiotic resistance patterns or the organisms causing UTIs are not adequately reflected in routine data. We studied the sensitivity of Escherichia coli (E. coli) to trimethoprim (TMP) and to cotrimoxazole (i.e., trimethoprim/sulfamethoxazole, TMP/SMX) in community-acquired UTI and compared the findings with the resistance data of the Antimicrobial Resistance Surveillance System (ARS). Methods: General practitioners and internists in private practice prospectively recruited all of their adult patients with symptoms of a urinary tract infection from May 2015 to February 2016. Urine specimens from all patients were tested (including urine culture testing and antibiotic susceptibility) and infections were defined as uncomplicated or complicated UTIs. Results: 1245 participants from 58 medical practices were enrolled in the study. Pathogenic organisms were found in the urine of 877 patients, of whom 74.5% had E. coli infections. Among the E.-coli-positive UTIs, 52.4% were classified as uncomplicated and 47.6% as complicated. The prevalence of E. coli that was resistant to TMP and to TMP/SMX in uncomplicated UTIs was 15.2% and 13.0%, respectively, compared to 25.3% and 24.4%, respectively, from all UTIs in ARS in 2015. Study participants who had previously taken antibiotics had the highest prevalence of E. coli resistance (30.9%), followed by those who had two or more UTIs within the past six months (28.9%). Conclusion: E. coli with resistance to TMP was significantly less prevalent among the study patients with uncomplicated UTIs than in the routine data of the ARS. Accordingly, TMP should still be considered as an option for the treatment of uncomplicated UTIs. TMP/SMX is considered the agent of second choice because of its side effects. Surveillance systems based on routine data do not yield a representative sample for the evaluation of the resistance situation in patients with uncomplicated UTIs.

Extended-spectrum β-lactamase (ESBL) producing Klebsiella pneumoniae pose an important threat of infection with increased morbidity and mortality, especially for immunocompromised patients. Here, we use the rise of multidrug-resistant K. pneumoniae in a German neurorehabilitation center from April 2015 to April 2016 to dissect the benefit of whole genome sequencing (WGS) for outbreak analyses. In total, 53 isolates were obtained from 52 patients and examined using WGS. Two independent analysis strategies (reference-based and -free) revealed the same distinct clusters of two CTX-M-15 producing K. pneumoniae clones (ST15, n = 31; ST405, n = 7) and one CTX-M-15 producing Klebsiella quasipneumoniae strain (ST414, n = 8). Additionally, we determined sequence variations associated with antimicrobial resistance phenotypes in single isolates expressing carbapenem and colistin resistance, respectively. For rapid detection of the major K. pneumoniae outbreak clone (ST15), a selective triplex PCR was deduced from WGS data of the major outbreak strain and K. pneumoniae genome data deposited in central databases. Moreover, we introduce two novel open-source applications supporting reference genome selection (refRank; https://gitlab.com/s.fuchs/refRank) and alignment-based SNP-filtering (SNPfilter; https://gitlab.com/s.fuchs/snpfilter) in NGS analyses.

Background. Increased nitric oxide (NO) production may contribute to intestinal barrier dysfunction and increased bacterial translocation (BT). Since BT may play a major role in graft-versus-host disease (GVHD) after small bowel transplantation (SBTx), we evaluated the role of NO production in GVHD after SBTX in the rat. Methods. Using the standard model of semiallogeneic SBTx in the rat, we prepared three experimental groups. Recipients in group 1 received LBNF 1 -LBNF 1 transplants and were treated with aminoguanidine (AG) (200 mg/kg), recipients in group 2 received Lewis-LBNF 1 grafts and were injected with saline, and recipients in group 3 received Lewis-LBNF 1 transplants and AG (200 mg/kg). Urine nitrite/nitrate levels were measured daily, and BT was determined by culturing peritoneal swabs, mesenteric lymph nodes, spleen, liver, and blood. Results. In group 1 we detected indefinite survival with normal histology. In group 2 a survival of 10.5±1.1 days was reached, and the typical histological features of acute GVHD were observed. The animals in group 3 showed a mean survival of 14.8±0.6 days (P

Between 1987 and 1992 we performed forensic-pathologic and neuropathologic examinations on 70 cases of i.v. drug addicts who died of an overdose. In almost 25% of the cases HIV-positivity was revealed by serological examinations. In all the cases, irrespective of the result of the serological examination, a diffuse, reactive astrocytosis was the most prominent histologic alteration, accompanied by more or less pronounced regressive changes of this cell type in the deep layers of the white matter. Furthermore, also in all the cases, a slight to moderate, reactive proliferation of microglia could be assessed. In a few cases of the HIV-seropositive group a lymphocytic meningitis, viz. meningoencephalitis was found; these changes may indicate an early invasion of the central nervous system (CNS) by the HIV. In spite of these inflammatory alterations, in the latter cases no HIV-specific antigens (p24 and gp41) could be demonstrated in the brain, most probably because of the small number of infectious particles. In order to reveal the earliest phase of invasion of the CNS by the HIV, we performed a search for HIV-specific nucleic acid sequences by the aid of the polymerase chain reaction (PCR) in 8 HIV-seronegative and 8 normal control cases. Although, most probably due to contamination, also the control cases exhibited some PCR-signals, these were more pronounced and appeared with more primer-pairs within the group of HIV-seronegative drug addicts. It is conceivable that HIV penetrates the CNS and is harboured in it in latent form shortly after the primary infection. This organ is, to a certain degree, isolated from and protected against the activity of the immune system by the blood barrier. Additionally, both HIV-infection and opiates have an immunosuppressive effect, so that the i.v. drug addicts are double endangered against all kinds of infections. These circumstances are advantageous for the persistence of HIV-infection within the brain.

The new VITEK 2 system is a fully automated system dedicated to the identification and susceptibility testing of microorganisms. In conjunction with the VITEK ID-YST card the VITEK 2 system allows the identification of clinically important yeasts and yeast-like organisms in 15 h due to a sensitive fluorescence-based technology. The ID-YST card consists of 47 biochemical reactions. The database comprises 51 taxa, including newly described species. In this study we evaluated the reliability of the VITEK ID-YST card for the identification of yeasts and yeast-like organisms encountered in a clinical microbiology laboratory. A total of 241 strains representing 21 species were studied. The strains were isolated from clinical samples within a period of 60 days prior to the identification. The tests were performed using 24-h to 55-h subcultures on Sabouraud-gentamicin-chloramphenicol agar. Each strain was tested in parallel using the ID 32C strip as a comparison method combined with microscopic morphology and an agglutination test for C. krusei . Overall, 222 strains (92.1%) were unequivocally identified including 11 isolates (4.6%) identified with low discrimination resolved by simple additional tests. Ten strains (4.1%) for which results were given with low discrimination could not be unequivocally identified with supplemental tests, 4 strains (1.7%) were misidentified and 5 strains (2.1%) could not be identified. In conclusion, we found that the VITEK 2 system is a rapid and accurate method for the identification of medically important yeasts and yeast-like organisms.

A case of Lactobacillus rhamnosus -associated peritonitis in a patient undergoing continuous ambulatory peritoneal dialysis is reported. The patient was treated with vancomycin after isolation of glycopeptide-susceptible coagulase-negative staphylococci. After a skin rash developed, vancomycin was discontinued and replaced with teicoplanin. Seven weeks after the glycopeptide therapy was discontinued, a Lactobacillus strain was isolated in pure cultures. The isolate was identified first incorrectly as L. acidophilus but later correctly as L. rhamnosus . Antibiotic susceptibility testing showed that the isolate was resistant to glycopeptides but susceptible to several other antibiotics. The antibiotic treatment was then switched to imipenem and was successful.