Successful control of Candida auris transmission in a German COVID-19 intensive care unit.

BACKGROUND: Candida auris a frequently multidrug-resistant yeast species that poses a global health threat due to its high potential for hospital outbreaks. While C. auris has become endemic in parts of Asia and Africa, transmissions have so far rarely been reported in Western Europe except for Great Britain and Spain. We describe the first documented patient-to-patient transmission of C. auris in Germany in a COVID-19 intensive care unit (ICU) and infection control measures implemented to prevent further spread of the pathogen. METHODS: Identification of C. auris was performed by MALDI-TOF and confirmed by internal transcribed spacer (ITS) sequencing. Antifungal susceptibility testing was carried out. We conducted repeated cross-sectional examinations for the presence of C. auris in the patients of the affected ICU and investigated possible routes of transmission. RESULTS: The index patient had been transferred to Germany from a hospital in Northern Africa and was found to be colonised with C. auris. The contact patient developed C. auris sepsis. Infection prevention and control (IPC) measures included strict isolation of the two C. auris patients and regular screening of non-affected patients. No further case occurred during the subsequent weeks. Reusable blades used in video laryngoscope-guided intubation were considered as the most likely vehicle of transmission. CONCLUSIONS: In view of its high risk of transmission, vigilance regarding C. auris colonisation in patients referred from endemic countries is crucial. Strict and immediate IPC measures may have the potential to prevent C. auris outbreaks.

Vector-borne pathogens in clinically healthy military working dogs in eastern Austria.

Military working dogs have an increased risk of acquiring an infection with vector-borne pathogens due to kennel housing and regular exposure to wildlife and vectors. To evaluate the level of infections in clinically healthy dogs of the Austrian Armed Forces, 94 individuals of the Military Working Dog Training Centre (MWDTC) Kaisersteinbruch/eastern Austria were examined in August 2016, February 2019 and August 2019. A modified Knott test was used to determine the presence of microfilariae, PCR for DNA detection of filarioid nematodes (incl. Dirofilaria), Leishmania spp., piroplasms, Borrelia spp., Bartonella spp. and Anaplasmataceae, and serological examination for antibodies against Borrelia burgdoferi s. l. and Leishmania infantum in all dogs. Two dogs were positive for Dirofilaria repens in the Knott test, and one of them also by PCR. Six clinically healthy dogs (4.2%) were positive for Babesia canis (PCR). In serology, 10 (10.6%) of the dogs were positive for specific antibodies against Borrelia burgdoferi s. l. The results suggest that the current measures against arthropod vector exposure and the pathogens they can transmit are not fully sufficient for these dogs. Further investigations of the tick and mosquito fauna in this area will shed more light on the risk of exposure for both the dogs and the staff of the MWDTC.

Molecular typing and in vitro resistance of Cryptococcus neoformans clinical isolates obtained in Germany between 2011 and 2017.

Cryptococcosis is a fungal infection of the central nervous system predominantly caused by Cryptococcus neoformans in immunocompromised patients. In several countries worldwide, up to 50% of isolates show in vitro resistance to clinically used antifungals including fluconazole. No prospective data on susceptibility to antifungal drugs are available for Germany. In this study, we characterised all C. neoformans isolates collected from individual patients' samples at the German reference laboratory for cryptococcosis 2011 and 2017 (n = 133) by multi-locus sequence typing and phenotypic drug susceptibility testing. We identified serotype A/genotype VNI isolates belonging to clonal complexes previously described from Europe, Africa, Asia and South America as the most prevalent agents of cryptococcosis in Germany. Overall, we observed minimal inhibitory concentrations (MICs) above the epidemiological cut-offs (ECVs) in 1.6% of isolates regarding fluconazole and 2.3% of isolates regarding 5-flucytosine. Here, two C. neoformans var. grubii isolates displayed decreased drug susceptibility to fluconazole, one of them additionally to 5-flucytosine. We also found 5-flucytosine MICs above the ECV for two C. neoformans var. neoformans isolates. We identified a novel mutation in the ERG11 gene which might be associated with the elevated fluconazole MIC in one of the isolates. The clinical importance of the detected in vitro resistance is documented by patient histories showing relapsed infection or primary fatal disease. Of note, sertraline demonstrated antifungal activity comparable to previous reports. Systematic collection of susceptibility data in combination with molecular typing of C. neoformans is important to comprehensively assess the spread of isolates and to understand their drug resistance patterns.

Association of angiopoietin-2 and dimethylarginines with complicated course in patients with leptospirosis.

Leptospirosis is one of the most relevant zoonosis worldwide and a potentially life-threatening infectious disease. While it is frequent in tropic regions, it is uncommon in European industrialized countries. Angiopoietin-2 (Angpt-2) and asymmetric and symmetric dimethylarginine (ADMA and SDMA) are markers of endothelial activation and systemic inflammation. These parameters have been studied recently in the context of sepsis and MODS showing potential to determine disease severity and outcome specific parameters like acute kidney injury (AKI) and survival. These biomarkers were measured in 13 patients with leptospirosis. High levels of Angpt-2 were statistically significant associated with a complicated clinical course with occurrence of AKI, Sepsis and intensive care unit treatment. ADMA was significantly associated with occurrence of AKI and ICU treatment whereas SDMA was associated with AKI. Therefore these endothelial markers may serve as additional tools for risk stratification in these patients.

Effects of catheter ablation of "asymptomatic" frequent ventricular premature complexes in patients with reduced (<48%) left ventricular ejection fraction.

Frequent ventricular premature complexes (VPCs), particularly those without troublesome palpitations, are often regarded as a benign arrhythmia and are not treated other than with reassurance. However, VPCs can contribute to left ventricular (LV) dysfunction in the absence of symptoms. The present study was designed to investigate whether catheter ablation of VPCs can improve LV dysfunction in patients with and without troublesome palpitations. Of 80 consecutive patients who underwent catheter ablation of frequent VPCs, 24 (aged 60 ± 15 years) were found to have a reduced LV ejection fraction at baseline (<48%) and included in the present study. No important procedure-related complications occurred in these patients. During a median follow-up of 8 months, the VPC burden after ablation had decreased from 15 ± 6% to 1 ± 1% (p <0.001), and the left ventricular ejection fraction had increased from 32 ± 15% to 43 ± 14% (p <0.001). Ten patients (42%) had no palpitations before ablation. In the other 14 patients, the palpitations were improved or entirely resolved after ablation. No significant difference was found in the extent of LV ejection fraction improvement after ablation between patients with and without palpitations (+11 ± 12% vs +11 ± 11%, p = 0.941) or between patients with different locations of VPC origin. In conclusion, VPCs might not necessarily be associated with palpitations in many patients with LV dysfunction. Successful ablation of frequent VPCs in these "asymptomatic" patients is associated with an improvement in LV function similar to that observed in "symptomatic" patients.

The influence of the potassium promoter on the kinetics and thermodynamics of CO adsorption on a bulk iron catalyst applied in Fischer-Tropsch synthesis: a quantitative adsorption calorimetry, temperature-programmed desorption, and surface hydrogenation study.

The adsorption of carbon monoxide on an either unpromoted or potassium-promoted bulk iron catalyst was investigated at 303 K and 613 K by means of pulse chemisorption, adsorption calorimetry, temperature-programmed desorption and temperature-programmed surface reaction in hydrogen. CO was found to adsorb mainly molecularly in the absence of H(2) at 303 K, whereas the presence of H(2) induced CO dissociation at higher temperatures leading to the formation of CH(4) and H(2)O. The hydrogenation of atomic oxygen chemisorbed on metallic iron was found to occur faster than the hydrogenation of atomically adsorbed carbon. At 613 K CO adsorption occurred only dissociatively followed by recombinative CO(2) formation according to C(ads) + 2O(ads)→ CO(2(g)). The presence of the potassium promoter on the catalyst surface led to an increasing strength of the Fe-C bond both at 303 K and 613 K: the initial differential heat of molecular CO adsorption on the pure iron catalyst at 303 K amounted to 102 kJ mol(-1), whereas it increased to 110 kJ mol(-1) on the potassium-promoted sample, and the initial differential heat of dissociative CO adsorption on the unpromoted iron catalyst at 613 K amounted to 165 kJ mol(-1), which increased to 225 kJ mol(-1) in the presence of potassium. The calorimetric CO adsorption experiments also reveal a change of the energetic distribution of the CO adsorption sites present on the catalyst surface induced by the potassium promoter, which was found to block a fraction of the CO adsorption sites.

False-positive Aspergillus antigen testing due to application of piperacillin/tazobactam--is it still an issue?

We evaluated the impact of piperacillin/tazobactam (PT) therapy on galactomannan enzyme immunoassay (GEI) testing (Platelia; Bio-Rad, Marnes La Coquette, France). Galactomannan contents of PT batches were highly variable. We found that false-positive GEI results can be avoided by performance of blood sampling before PT administration and by using separate sites for blood sampling and for administration of antibiotics.

Use of denaturing high-performance liquid chromatography for rapid detection and identification of seven Candida species.

A novel denaturing high-performance liquid chromatography (DHPLC)-based technique allows rapid high-resolution analysis of PCR products. We used this technique for unequivocal molecular identification of seven Candida species. We show the application of this PCR/DHPLC approach for direct detection and identification of yeast species from blood cultures and for detection of Candida colonization in the gastrointestinal tract of allogeneic transplant patients.

Rapid and simple differentiation of C. dubliniensis from C. albicans.

Differentiation of Candida dubliniensis from C. albicans using biochemical methods is time consuming and may be difficult to achieve because of ambiguous results. Here, we describe a simple, rapid and inexpensive method for unequivocal differentiation of C. dubliniensis from C. albicans using polymerase chain reaction (PCR)/RFLP.

Identification of clinically relevant yeasts by PCR/RFLP.

For molecular diagnosis of fungal disease using DNA amplification procedures in the routine laboratory, choice of appropriate target structures and rapid and inexpensive identification of amplification products are important prerequisites. Most diagnostic procedures described thus far are characterized by limited applicability, considerable cost for laboratory equipment or low power of discrimination between species. This study aimed at identification of a PCR target appropriate for diagnosis of clinically relevant yeasts and an affordable procedure for characterization of the PCR products to the species level. Here, we describe a PCR-based system using amplification of intergenic spacers ITS1 and ITS2 and restriction length polymorphism of PCR products after sequence-specific enzymatic cleavage. We show the evaluation of the system for clinically relevant Candida species. The simple and inexpensive procedure should be instrumental for rapid identification of medically important yeasts.

Prevalence and molecular diversity of pHS-2 plasmids, marker for arthritogenicity, among clinical Escherichia coli Shigella isolates.

Reactive arthritis can occur after numerous bacterial infections, including bacillary dysentery caused by Escherichia coli Shigella. A major risk factor for the disease is the HLA B27 phenotype in the human host. By comparison between plasmid profiles of arthritogenic vs. nonarthritogenic Shigella strains, the pHS-2 plasmid has been previously associated with the arthritogenic capacity of Shigella isolates. However, the prevalence of this plasmid in the various Shigella biotypes and serotypes is largely unknown. On this background, 188 clinical isolates from intestinal disease representing all 46 Shigella serogroups were studied for the presence of the pHS-2 plasmid, using PCR, dot blot and Southern blot techniques and by analysis of restriction fragment length polymorphisms. The pHS-2 plasmid was found in nine of 14 E. coli Flexneri serogroups, in E. coli Dysenteriae 1 and in E. coli Boydii 16. In addition, we show marked variability of this plasmid in E. coli Flexneri 3A and 4A strains. Major biological diversity of the pHS-2 plasmid was found to be strictly related to Shigella serogroups. The prevalence pattern of the pHS-2 plasmid matches published data on arthritogenic Shigella isolates, providing additional indirect evidence for the potential validity of this plasmid as a marker for arthritogenicity.