Search

Abstract Background Carbapenem-resistant Acinetobacter baumannii (CRAB) frequently causes both healthcare-associated infections and nosocomial outbreaks in burn medicine/plastic surgery and beyond. Owing to the high antibiotic resistance, infections are difficult to treat, and patient outcomes are often compromised. The environmental persistence capability of CRAB favors its transmission in hospitals. A comprehensive analysis and understanding of CRAB epidemiology and microbiology are essential for guiding management. Methods A three-year retrospective cohort study (2020–2022) was conducted in a German tertiary burn and plastic surgery center. In addition to epidemiological analyses, microbiological and molecular techniques, including whole-genome sequencing, were applied for the comprehensive examination of isolates from CRAB-positive patients. Results During the study period, eight CRAB cases were found, corresponding to an overall incidence of 0.2 CRAB cases per 100 cases and an incidence density of 0.35 CRAB cases per 1000 patient-days. Six cases (75%) were treated in the burn intensive care unit, and four cases (50%) acquired CRAB in the hospital. Molecular analyses comprising 74 isolates supported the epidemiologic assumption that hospital acquisitions occurred within two separate clusters. In one of these clusters, environmental CRAB contamination of anesthesia equipment may have enabled transmission. Furthermore, molecular diversity of CRAB isolates within patients was observed. Conclusions CRAB can pose a challenge in terms of infection prevention and control, especially if cases are clustered in time and space on a ward. Our study demonstrates that high-resolution phylogenetic analysis of several bacterial isolates from single patients can greatly aid in understanding transmission chains and helps to take precision control measures.

PurposeThe significance of atraumatic electrode array (EA) insertion in cochlear implant (CI) surgery is widely acknowledged, with consensus that forces due to EA insertion are directly correlated with insertion trauma. Unfortunately, the manual perception of these forces through haptic feedback is inherently limited, and techniques for in vivo force measurements to monitor the insertion are not yet available. Addressing this gap, we developed of a force-sensitive insertion tool capable of capturing real-time insertion forces during standard CI surgery.MethodsThis paper describes the tool and its pioneering application in a clinical setting and reports initial findings from an ongoing clinical study. Data and experiences from five patients have been evaluated so far, including force profiles of four patients.ResultsThe initial intraoperative experiences are promising, with successful integration into the conventional workflow. Feasibility of in vivo insertion force measurement and practicability of the tool’s intraoperative use could be demonstrated. The recorded in vivo insertion forces show the expected rise with increasing insertion depth. Forces at the end of insertion range from 17.2 mN to 43.6 mN, while maximal peak forces were observed in the range from 44.8 mN to 102.4 mN.ConclusionWe hypothesize that this novel method holds the potential to assist surgeons in monitoring the insertion forces and, thus, minimizing insertion trauma and ensuring better preservation of residual hearing. Future data recording with this tool can form the basis of ongoing research into the causes of insertion trauma, paving the way for new and improved prevention strategies.

Abstract The COVID-19 pandemic has made it clear: sharing and exchanging data among research institutions is crucial in order to efficiently respond to global health threats. This can be facilitated by defining health data models based on interoperability standards. In Germany, a national effort is in progress to create common data models using international healthcare IT standards. In this context, collaborative work on a data set module for microbiology is of particular importance as the WHO has declared antimicrobial resistance one of the top global public health threats that humanity is facing. In this article, we describe how we developed a common model for microbiology data in an interdisciplinary collaborative effort and how we make use of the standard HL7 FHIR and terminologies such as SNOMED CT or LOINC to ensure syntactic and semantic interoperability. The use of international healthcare standards qualifies our data model to be adopted beyond the environment where it was first developed and used at an international level.

Abstract Objective: The present study aims to develop and discuss an extension of hospital-acquired severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections (HA-SIs) definition which goes beyond the use of time parameters alone. Design: A confirmatory factor analysis was carried out to test a suitable definition for HA-SI. Setting and Patients: A two-center cohort study was carried out at two tertiary public hospitals in the German state of lower Saxony. The study involved a population of 366 laboratory-confirmed SARS-CoV-2-infected inpatients enrolled between March 2020 and August 2023. Results: The proposed model shows adequate fit indices (CFI.scaled = 0.959, RMSEA = 0.049). A descriptive comparison with existing classifications revealed strong features of our model, particularly its adaptability to specific regional outbreaks. Conclusion: The use of the regional incidence as a proxy variable to better define HA-SI cases represents a pragmatic and novel approach. The model aligns well with the latest scientific results in the literature. This work successfully unifies, within a single model, variables which the recent literature described as significant for the onset of HA-SI. Further potential improvements and adaptations of the model and its applications, such as automating the categorization process (in terms of hospital acquisition) or employing a comparable model for hospital-acquired influenza classification, are subjects open for discussion.

Vancomycin-resistant enterococci (VRE) occur in hospitalized patients, causing both infection and colonization. In recent years, there has been an increase in VRE in German and other hospitals, raising the question of how to control this epidemic best. To better understand the specific epidemiology and to guide infection control, we conducted a retrospective cohort study analyzing all patients with VRE at Hannover Medical School, a tertiary university clinic in Germany that specializes in solid organ transplantation. Epidemiologic and clinical characteristics of patients with VRE from 2015-2017 were collected. Basic epidemiologic parameters, including VRE incidence and incidence density, were calculated. Independent risk factors for nosocomial VRE infection compared to colonization were assessed using a logistic regression model. There were 1,492 VRE cases corresponding to 822 individual patients. The incidence was 0.8 VRE cases per 100 cases. A total of 536 (35.9%) of the 1,492 VRE cases were acquired nosocomially. Of the 1,492 cases, 912 cases had VRE-positive samples (894 Enterococcus (E.) faecium and 18 E. faecalis) in our hospital laboratory and the remaining cases were known VRE carriers. The vanB-phenotype was observed in 369 of the 894 (41.3%) E. faecium isolates and in 6 of the 18 (33.3%) E. faecalis isolates. There was an increase over time in the vanB-phenotype proportion in E. faecium (2015: 63 of 171, 36.8%, 2016: 115 of 322, 35.7% and 2017: 191 of 401, 47.6%). A total of 107 cases had a VRE infection (7.2% of all VRE cases) according to the criteria of the German National Reference Center for Surveillance of Nosocomial Infections. The remaining cases were only colonized. Among other factors, leukocytopenia (

ABSTRACT Nitroxoline (NTX) is an antibiotic approved for the treatment of uncomplicated urinary tract infections (UTIs) caused by Enterobacteriaceae like Escherichia coli, and it has been on the market for more than 50 years. Despite being in use longer than several other clinically relevant antibiotics, the resistance of clinical isolates against NTX has not evolved significantly. To better understand this observation, we performed a standardized in vitro evaluation of NTX in comparison to other UTI drugs with a focus on resistance development and especially their consequences. We have managed to generate low-level resistant mutants in E. coli and Klebsiella pneumoniae using a long-term exposure setup, and identified mutations in different efflux-related genes and in other pleiotropic regulators as well as the sensor histidine kinase envZ. Subsequently, mutants were characterized by metabolic and proteomic analyses confirming major effects of NTX resistance on both metabolism and differential protein expression of E. coli, which ultimately also translates into reduced in vitro motility and in vivo virulence of mutant strains as shown in a zebrafish larvae infection model. IMPORTANCE Antimicrobial resistance (AMR) poses a global threat and requires the exploration of underestimated treatment options. Nitroxoline, an effective broad-spectrum antibiotic, does not suffer from high resistance rates in the clinics but surprisingly, it is not heavily used yet. Our findings provide compelling evidence that Nitroxoline resistance renders bacteria unable to cause an infection in vivo, thereby reinvigorating the potential of Nitroxoline in combating AMR.

Abstract Background Respiratory syncytial virus (RSV) causes community-acquired respiratory tract infections during winter. However, outbreaks in hospitals also occur repeatedly. In particular, patients with hematologic malignancies are at an increased risk for a severe and potentially fatal course of RSV infection. Here we present the investigation of an RSV outbreak in a hematology ward for adults following the ORION statement. Methods An epidemiologic and molecular outbreak analysis was performed. We developed and employed a minimal oligonucleotide probe set in target capture probe sequencing that allows cost-effective RSV-A or -B capturing to reconstruct RSV genomes from clinical samples. Results Four adult patients were involved in the outbreak caused by RSV-B in March 2019. The enforcement of the pre-existing infection control measures by effective training of hospital staff contributed to a successful containment. PCR-based RSV screening on the ward enabled early detection of new cases and rapid isolation measures. The molecular analysis demonstrated that the outbreak sequences were highly related and distinct to other RSV-B strains circulating at the same time. Conclusions A multimodal infection control concept is essential for the timely detection and control of RSV outbreaks in patients with hematological disease. Among other measures, preventive screening for respiratory viruses is recommended. Furthermore, the integration of conventional and molecular epidemiology, such as whole-genome sequencing and variant calling, significantly contributes to the understanding of transmission pathways. Based on this, appropriate conclusions can be drawn for targeted prevention measures that have prepared us for the COVID-19 pandemic beyond the RSV approach described here.

Abstract Background Hand hygiene using alcoholic hand rub solution is essential for the prevention of surgical site infections. There are several opportunities for hygienic hand disinfection (termed “hand hygiene” in the following) during immediate pre-, intra- and postoperative orthopedic patient care. However, the level of hand hygiene compliance among surgical and anesthesia staff in this context is unclear. Therefore, we conducted an observational study in operating theatres of an orthopedic university clinic in northern Germany during July and August 2020. Methods One trained person directly and comprehensively observed hand hygiene compliance of surgical and anesthesia staff according to the WHO “My 5 moments for hand hygiene” model (WHO-5). In addition to cross-tabulations with Chi2 tests, multiple logistic regression models were used to study associations between occupational group, medical specialty, and compliance (both overall and for each WHO-5 indication). Models were adjusted for hand hygiene opportunities being associated with female or male healthcare workers, being located within or outside the operation room, and occurring in adult or pediatric surgery. Results In total, 1145 hand hygiene opportunities during 16 surgeries were observed. The overall compliance was 40.8% (95% CI 37.9–43.6%), with a larger difference between surgical versus anesthesia staff (28.4% vs. 46.1%, p

Background Appropriate preoperative skin cleansing is important to control surgical site infections. Both colored and colorless skin disinfectants are available, however certain types of skin preparation, such as octenidine-dihydrochloride with alcohol have a long residual antimicrobial effect but are available only in colorless form. We hypothesized that colorless skin disinfectants lead to more incomplete skin preparation of lower limbs compared to colored agents. Methods We randomly assigned healthy volunteers to undergo a determined skin cleansing protocol for total hip arthroplasty in the supine position to either a colored or colorless skin cleansing protocol. The adequacy of skin preparation was compared between orthopedic consultants and residents. The colorless disinfectant was mixed with a fluorescent dye and missed skin areas were visualized using UV lamps. Both preparations were photo-documented following standardized protocols. The primary outcome of interest was the number of legs with an incomplete scrubbed area. The secondary outcome was the cumulative skin area not disinfected. Results Fifty-two healthy volunteers (104 legs; 52 colored and 52 colorless) underwent surgical skin preparation. The number of legs incompletely disinfected was significantly higher in colorless compared to colored disinfectant group (38.5% (n = 20) vs. 13.5% (n = 7); p = 0.007). Regardless of the disinfectant, consultants performed better than the residents. When using colored disinfectant, residents incompletely prepared the site in 23.1% (n = 6) compared with 57.7% (n = 15) with a colorless disinfectant (p = 0.023). Conversely consultants using colored disinfectant incompletely prepared the site in 3.8% (n = 1) compared with 19.2% (n = 5) for colorless disinfectant (p = 0.191). The total amount of uncleansed skin was significantly higher using colorless skin disinfectant (mean ± standard deviation: 8.78 cm2± 35.07 vs. 0.65 cm2 ± 2.66, p = 0.002). Conclusions Application of colorless skin disinfectants for hip arthroplasty cleansing protocol led to decreased skin coverage among consultants and residents compared to colored preparations. Colored disinfectants remain the gold standard in hip surgery, however we should be aiming to develop newer colored disinfectants with long residual antimicrobial effects to enable visual control during the scrubbing process.

Abstract Background Carbapenem resistant (CR) Klebsiella pneumoniae (Kp) and Acinetobacter baumannii (Ab) are emerging multidrug resistant bacteria with very limited treatment options in case of infection. Both are well-known causes of nosocomial infections and outbreaks in healthcare facilities. Methods A retrospective study was conducted to investigate the epidemiology of inpatients with CR Kp and CR Ab in a 1500-bed German university hospital from 2015 to 2019. We present our infection control concept including a weekly microbiologic screening for patients who shared the ward with a CR Kp or CR Ab index patient. Results Within 5 years, 141 CR Kp and 60 CR Ab cases were hospitalized corresponding to 118 unique patients (74 patients with CR Kp, 39 patients with CR Ab and 5 patients with both CR Ab and CR Kp). The mean incidence was 0.045 (CR Kp) and 0.019 (CR Ab) per 100 inpatient cases, respectively. Nosocomial acquisition occurred in 53 cases (37.6%) of the CR Kp group and in 12 cases (20.0%) of the CR Ab group. Clinical infection occurred in 24 cases (17.0%) of the CR Kp group and in 21 cases (35.0%) of the CR Ab group. 14 cases (9.9%) of the CR Kp group and 29 cases (48.3%) of the CR Ab group had a history of a hospital stay abroad within 12 months prior to admission to our hospital. The weekly microbiologic screening revealed 4 CR Kp cases caused by nosocomial transmission that would have been missed without repetitive screening. Conclusions CR Kp and CR Ab cases occurred infrequently. A history of a hospital stay abroad, particularly in the CR Ab group, warrants pre-emptive infection control measures. The weekly microbiologic screening needs further evaluation in terms of its efficiency.

Abstract The spread of multidrug resistant organisms (MDRO) is a global healthcare challenge. Nosocomial outbreaks caused by MDRO are an important contributor to this threat. Computer-based applications facilitating outbreak detection can be essential to address this issue. To allow application reusability across institutions, the various heterogeneous microbiology data representations needs to be transformed into standardised, unambiguous data models. In this work, we present a multi-centric standardisation approach by using openEHR as modelling standard. Data models have been consented in a multicentre and international approach. Participating sites integrated microbiology reports from primary source systems into an openEHR-based data platform. For evaluation, we implemented a prototypical application, compared the transformed data with original reports and conducted automated data quality checks. We were able to develop standardised and interoperable microbiology data models. The publicly available data models can be used across institutions to transform real-life microbiology reports into standardised representations. The implementation of a proof-of-principle and quality control application demonstrated that the new formats as well as the integration processes are feasible. Holistic transformation of microbiological data into standardised openEHR based formats is feasible in a real-life multicentre setting and lays the foundation for developing cross-institutional, automated outbreak detection systems.

Introduction: Vancomycin-resistant enterococci (VRE) are emerging multidrug-resistant bacteria. They can cause serious nosocomial infections, especially in immunocompromised patients. Objectives and methods: In this study, we aimed to determine the burden of intestinal VRE colonization and clinically relevant infection in adult hematologic and oncologic patients at a tertiary care clinic in Germany based on prospective infection surveillance and an active screening program. Results: In a 12 month period, 132 of 555 patients had intestinal VRE-colonization (23.8%) and four patients (0.7% of the entire cohort, and 3.0% of those colonized with VRE) developed a nosocomial infection with VRE. Conclusions: The prospective surveillance and active screening for VRE was very useful to determine the true ratio of intestinal colonization to infection and thus helps to shape infection control management.

In preterm and term infants who require intermediate or intensive care Methicillin-resistant Staphylococcus aureus (MRSA) infection can lead to significant morbidity. In this study MRSA colonization and infection were assessed in a mixed tertiary neonatal intensive and intermediate care unit in Germany over an 8-year period (2013–2020). We investigated patient-related factors, associated with nosocomial MRSA acquisition, and we discuss our infection control concept for MRSA. Of 3488 patients treated during the study period, 24 were MRSA positive patients, corresponding to 26 patient hospital stays. The incidence was 0.7 MRSA patients per 100 patients. The incidence density was 0.4 MRSA patient hospital stays per 1000 patient days. Twelve patients (50%) acquired MRSA in the hospital. One patient developed a hospital acquired MRSA bloodstream infection 9 days after birth (i.e., 0.03% of all patients on the ward during the study period). A total of 122 patients had to be screened to detect one MRSA positive patient. In a logistic regression model, the use of 3rd generation intravenous cephalosporin (cefotaxim) was associated with nosocomial MRSA acquisition compared with matched control patients who did not acquire MRSA. In sum, the burden of MRSA colonization and infection in the ward was low during the study period. A comprehensive infection control concept that included microbiologic colonization screening, prospective infection surveillance together with isolation and emphasis on basic hygiene measures is essential to handle MRSA in this specialized setting.

Abstract Hematopoietic stem cell transplantation (HSCT) is a curative treatment option for selected diseases of the hematopoietic system. In the context of HSCT, bloodstream infections caused by Gram-negative bacteria (GNB) significantly contribute to morbidity and mortality. Antibiotic treatment of bloodstream infections with carbapenem-resistant (CR) GNB presents a particular challenge. As a part of our infection control management, the admission of a patient who was known to be colonized with a CR Acinetobacter baumannii triggered an active weekly screening of all patients to determine the prevalence and potential transmission of CR GNB and CR Acinetobacter baumannii in particular. Over a 3 month period a total of 71 patients were regularly screened for colonization with CR GNB. Including the index patient, a total of three patients showed CR GNB colonization representing a prevalence of 4.2%. Nosocomial transmission of CR Acinetobacter baumannii or other CR GNB was not observed. However, the index patient developed a subsequent bloodstream infection with the CR Acinetobacter baumannii, therefore empiric antibiotic therapy based on the known resistance profile was initiated. A weekly prevalence screening for CR GNB might be an effective monitoring tool for potential transmission, may enhance existing infection control management concepts and may support the decision making for empiric antibiotic therapy.

Background: Burn patients are predisposed for nosocomial infections during their stay on a burn intensive care unit. Moreover, several outbreaks affecting burn units for example caused by Methicillin-resistant Staphylococcus aureus (MRSA) have been reported. One attempt to address these challenges is the use of universal decolonization. Methods: In 2015 we implemented universal decolonization for all burn patients using the antiseptic agent octenidine for intact skin and the nasopharyngeal mucosa. We conducted a retrospective analysis to evaluate the effect of the decolonization on primary, central line (central venous catheter)-associated bloodstream infections (CLABSI), the frequency of nosocomial clusters (4 or more cases with epidemiologic link and identical molecular pattern) with multidrug-resistant bacteria (MDRB) and the incidence of MRSA. Results: In the decolonization period a reduction of the incidence of CLABSI, nosocomial MRSA acquisition and the frequency of nosocomial MDRB clusters was observed. The incidence rate of CLABSI decreased from 2/1000 central venous catheter days in the pre-decolonization phase to 0.8/1000 central venous catheter days in the decolonization period, although this was not statistically significant. The implementation was accompanied by several feedback talks and training for the staff. The user experience was positive and no adverse effects occurred. Conclusion: Our results show that universal decolonization in burn patients using octenidine is a promising concept to address hospital acquisition of MRSA; occurrence of CLABSI as well as the spread of MDRB causing clusters. It is of high relevance to further assess the value of this measure in terms of reducing CLABSI in burn patients in larger study groups. Therefore further studies including more burn patients guaranteeing adequate sample size are needed. Keywords: Burn unit, Universal decolonization, Octenidine, Bloodstream infection, Multidrug-resistant bacteria, Nosocomial

There is a lack of data on factors that contribute to the implementation of hygiene measures during nosocomial outbreaks (NO) caused by Methicillin-resistant Staphylococcus aureus (MRSA). Therefore, we first conducted a systematic literature analysis to identify MRSA outbreak reports. The expenditure for infection control in each outbreak was then evaluated by a weighted cumulative hygiene score (WCHS). Effects of factors on this score were determined by multivariable linear regression analysis. 104 NO got included, mostly from neonatology (n = 32), surgery (n = 27), internal medicine and burn units (n = 10 each), including 4,361 patients (thereof 657 infections and 73 deaths) and 279 employees. The outbreak sources remained unknown in 10 NO and were not reported from further 61 NO. The national MRSA prevalence did not correlate with the WCHS (p = .714). There were significant WCHS differences for internal medicine (p = 0.014), burn units (p

Non-implanted central vascular catheters (CVC) are frequently required for therapy in hospitalized patients with hematological malignancies or solid tumors. However, CVCs may represent a source for bloodstream infections (central line-associated bloodstream infections, CLABSI) and, thus, may increase morbidity and mortality of these patients. A retrospective cohort study over 3 years was performed. Risk factors were determined and evaluated by a multivariable logistic regression analysis. Healthcare costs of CLABSI were analyzed in a matched case-control study. In total 610 patients got included with a CLABSI incidence of 10.6 cases per 1,000 CVC days. The use of more than one CVC per case, CVC insertion for conditioning for stem cell transplantation, acute myeloid leukemia, leukocytopenia (≤ 1000/μL), carbapenem therapy and pulmonary diseases were independent risk factors for CLABSI. Hospital costs directly attributed to the onset of CLABSI were 8,810 € per case. CLABSI had a significant impact on the overall healthcare costs. Knowledge about risk factors and infection control measures for CLABSI prevention is crucial for best clinical practice.

Introduction. Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for infections in patients both inside and outside of the hospital and causes outbreaks. Here, we demonstrate the characteristics and control of a MRSA outbreak related to a carbon dioxide hydrotherapy bathtub. Methods. We conducted an outbreak investigation and performed a molecular typing of the outbreak strains with pulsed-field gel electrophoresis (PFGE). In addition, we reviewed PubMed and the Outbreak Database for MRSA outbreaks related to hydrotherapy or other bathing activities. Results. Four patients acquired nosocomial MRSA during the 4-week outbreak period. Environmental sampling revealed the presence of MRSA in the bathtub used for hydrotherapy. The environmental and the patients’ isolates showed an indistinguishable restriction pattern in the PFGE. Subsequent discontinuation of bathing stopped the outbreak. The literature search found 9 MRSA outbreak reports related to bathing activities or hydrotherapy. Conclusion. The epidemiologic outbreak investigation together with the molecular findings suggests monoclonal spread of MRSA due to surface contamination of the bathtub. After enhancing the disinfection and cleaning process accompanied by staff training with respect to hand hygiene, no further cases occurred. Standardized and best practice cleaning and disinfection protocols are crucial, especially in critical facilities such as hydrotherapy units. Regular environmental sampling is helpful to monitor these processes and to detect potential contamination.

Abstract Background Respiratory syncytial virus (RSV) is responsible for upper and lower respiratory tract infection in adults and children. Especially immunocompromised patients are at high risk for a severe course of infection, and mortality is increased. Moreover RSV can spread in healthcare settings and can cause outbreaks. Herein we demonstrate the successful control and characteristics of a RSV outbreak that included 8 patients in our Department of Pediatric Hematology and Oncology. Methods We performed an epidemiologic investigation and a molecular analysis of the outbreak strains. Moreover we present the outbreak control bundle and our concept for RSV screening in the winter season. Results RSV A and B strains caused the outbreak. RSV B strains affected 3 patients, 2 of whom were co-infected with RSV A. Exactly this RSV A strain was detected in another 5 patients. Our multimodal infection control bundle including prophylactic RSV screening was able to rapidly stop the outbreak. Conclusion An infection control bundle in RSV outbreaks should address all potential transmission pathways. In pediatric settings the restriction of social activities might have a temporal negative impact on quality of life but helps to limit transmission opportunities. Molecular analysis allows better understanding of RSV outbreaks and, if done in a timely manner, might be helpful for guidance of infection control measures.