Carbapenem-resistant Gram-negative bacteria - analysis of the data obtained through a mandatory reporting system in the Rhine-Main region, Germany, 2012-2015

Colonization with multidrug-resistant organisms is associated with in increased mortality in liver transplant candidates

Objectives

Rising prevalence of multidrug-resistant organisms (MDRO) is a major health problem in patients with liver cirrhosis. The impact of MDRO colonization in liver transplantation (LT) candidates and recipients on mortality has not been determined in detail.

Methods

Patients consecutively evaluated and listed for LT in a tertiary German liver transplant center from 2008 to 2018 underwent screening for MDRO colonization including methicillin-resistant Staphylococcus aureus (MRSA), multidrug-resistant gram-negative bacteria (MDRGN), and vancomycin-resistant enterococci (VRE). MDRO colonization and infection status were obtained at LT evaluation, planned and unplanned hospitalization, three months upon graft allocation, or at last follow-up on the waiting list.

Results

In total, 351 patients were listed for LT, of whom 164 (47%) underwent LT after a median of 249 (range 0–1662) days. Incidence of MDRO colonization increased during waiting time for LT, and MRDO colonization was associated with increased mortality on the waiting list (HR = 2.57, p<0.0001. One patients was colonized with a carbapenem-resistant strain at listing, 9 patients acquired carbapenem-resistant gram-negative bacteria (CRGN) on the waiting list, and 4 more after LT. In total, 10 of these 14 patients died.

Conclusions

Colonization with MDRO is associated with increased mortality on the waiting list, but not in short-term follow-up after LT. Moreover, colonization with CRGN seems associated with high mortality in liver transplant candidates and recipients.

Anamnestic risk factor evaluation of patients carrying carbapenem-resistant Enterobacterales and/or Acinetobacter baumannii - impact on infection control management at a German University Hospital

Background: Carbapenem-resistant Enterobacterales and Acinetobacterbaumannii are of major concern in terms of infection prevention and control. This study evaluated factors that may increase the frequency of Enterobacterales and A. baumannii with carbapenem resistance (CR) in patients admitted to a German University Hospital for implementation of optimized infection control management.

Methods: A five-year-retrospective epidemiological cohort analysis was conducted on anamnestic risk factors for carrying Enterobacterales and/or A. baumannii with CR in patients who were first tested positive for these species at University Hospital Frankfurt (UHF) between January 2013 and June 2018.

Results: 364 patients were tested positive for Enterobacterales and/or A. baumannii with CR, resulting in n=400 bacterial isolates in total, with Klebsiella pneumoniae being the most frequently detected species (n=146/400; 36.5%; 95% confidence interval: 31.8–41.4). In patients who were tested positive for Enterobacterales and/or A. baumannii with CR, any hospital stay within the previous 12 months was the most frequently reported common factor (n=275/364; 75.5%; 70.8–79.9).

Conclusion: A hospital stay within the previous 12 months, including hospitals in Germany and abroad, is a frequent characteristic of patients who tested positive for Enterobacterales and/or A. baumannii with CR. Upon admission, any previous hospital stay of the given patient within the previous 12 months should be determined. Infection control strategies such as screening measures need to be adapted to these patient groups in hospital settings. In order to reflect the varying determinants in “nosocomial” cases in greater detail, the existing criteria used to characterize “nosocomial detection” of gram-negative bacteria with CR should be reviewed.

Carbapenem resistance among clinical and environmental Gram-negative isolates recovered from hospitals in Gaza strip, Palestine

Background

The world is threatened by the ongoing emergence of carbapenem resistant organisms, which are contributing to increasing morbidity and mortality rates. The main objective of this study was to highlight carbapenem resistance among clinical and environmental Gram-negative bacteria (GNB) isolates.

Methods

A cross-sectional study wherein 210 clinical isolates, 150 environmental swabs, and 110 air samples were collected from three major hospitals in Gaza strip: Al-Shifa, AlNaser and the European Gaza hospitals. The study lasted for seven months (September 2016 to March 2017). All isolates/samples were cultured and identified using conventional bacteriological methods. All GNB isolates were tested for their antimicrobial susceptibility using the disk diffusion method. Modified Hodge Test (MHT) was performed to investigate carbapenemases production.

Results

The overall percentage of carbapenem resistance among GNB was (30/247) 12.1%. Resistance to imipenem was (20/247) 8.1% while resistance to ertapenem and meropenem was (8/226) 3.5% and (2/247) 0.8%, respectively. The intensive care units exhibited the highest resistance rate 9/17 (52.9%). Carbapenem resistance among Enterobacteriaceae was (30/226) 13.2% while in Pseudomonas it was (0/21) 0%. Klebsiella spp. was the most resistant to carbapenems 13/90 (14.4%), followed by E. coli (9/91) 9.8%. Seven isolates out of 30 (23.3%) were positive for MHT. All Enterobacteriaceae isolates had a multiple antibiotic resistance (MAR) index higher than 0.2, while those of Pseudomonas had an average of 0.2. GNB were isolated from 19/110 (17.2%) and 21/150 (14%) of air and environmental samples, respectively.

Conclusion

The resistance found, after a recent introduction of carbapenem use in Gaza, shows the need for policies to prevent misuse and overuse of carbapenems, the need for infection control procedures and screening policies for carbapenem resistance on a routine basis.

Carbapenem-resistant Gram-negative pathogens in a German university medical center: Prevalence, clinical implications and the role of novel β-lactam/β-lactamase inhibitor combinations

Objectives

To determine the spectrum of infections with multidrug-resistant Gram-negative bacteria (MDR-GNB) and the clinical impact of the newly available betalactam/betalactamase inhibitor combinations ceftolozane/tazobactam and ceftazidime/avibactam in a German academic tertiary care center.

Methods

Retrospective analysis.

Results

Between September 1, 2015 and August 31, 2016, 119 individual patients (0.22% of all hospital admissions) were colonized or infected with carbapenem-resistant MDR-GNB. The species distribution was Pseudomonas aeruginosa, n = 66; Enterobacteriaceae spp., n = 44; and Acinetobacter baumannii, n = 18. In 9 patients, carbapenem-resistant isolates belonging to more than one species were detected. Infection was diagnosed in 50 patients (total: 42.0%; nosocomial pneumonia: n = 23, 19.3%; bloodstream infection: n = 11, 9.2%). Antimicrobial treatment with broad-spectrum antibiotics prior to detection of a carbapenem-resistant isolate was documented in 105 patients (88.2%, prior administration of carbapenems: 62.2%). Nosocomial transmission was documented in 29 patients (24.4%). In 26 patients (21.8%), at least one carbapenem-susceptible, third-generation cephalosporin non-susceptible isolate was documented prior to detection of a carbapenem-resistant isolate belonging to the same species (median 38 days, IQR 23–78). 12 patients (10.1%) had documented previous contact to the healthcare system in a country with high burden of carbapenemase-producing strains. Genes encoding carbapenemases were detected in 60/102 patient isolates (58.8%; VIM-2, n = 25; OXA-48, n = 21; OXA-23-like, n = 10). Susceptibility to colistin was 94.3%. Ceftolozane/tazobactam and ceftazidime/avibactam were administered to 3 and 5 patients, respectively (in-hospital mortality: 66% and 100%). Development of drug-resistance under therapy was observed for both antimicrobials.

Conclusions

i) The major predisposing factors for acquisition of carbapenem-resistant MDR-GNB were selective pressure due to preceding antimicrobial therapy and nosocomial transmission. ii) Colistin remains the backbone of antimicrobial chemotherapy for infections caused by carbapenem-resistant MDR-GNB. iii) Novel β-lactam/β-lactamase inhibitor combinations are of limited usefulness in our setting because of the high prevalence of Ambler class B carbapenemases and the emergence of nonsusceptibility under therapy.

Findings from an outbreak of carbapenem-resistant Klebsiella pneumoniae emphasize the role of antibiotic treatment for cross transmission

PURPOSE

In January 2015, we noticed by rectal swab analyses that seven of 23 patients at an early rehabilitation ward had been colonized with carbapenem-resistant Klebsiella pneumoniae (CKP). Here, we describe risk factors for CKP acquisition.

METHODS

In the present study, the outbreak is described and risk factors for CKP acquisition are examined, e.g., antibiotic treatment. Microbiological analyses including corresponding results were examined to study when colonization with CKP occurred and whether patients had suffered from diarrhea. To examine whether spread of bacteria was clonal, multi-locus sequence typing as well as Xbal macrorestriction and pulsed-field gel electrophoresis was performed. The presence of carbapenmase was examined by PCR analysis. Through univariate analysis of risk factors in the small study sample, the role of antibiotic consumption, isolation procedures, patient's age, gender, and Barthel index on colonization was elucidated.

RESULTS

Clonal spread of the novel sequence type (ST)2255 was identified. Additionally, one patient was colonized with Escherichia coli and Serratia marcescens, both resistant to carbapenems, while a further patient carried another carbapenem-resistant E. coli strain. In all isolates, carbapenemase gene bla _OXA-48 was found to be located on a conjugative plasmid (60 kb), suggesting in vivo transmission from CKP to E. coli and S. marcescens. Univariate tests indicated that antibiotic treatment was the only risk factor showing a significant association with being colonized by CKP. In addition, the likelihood of diarrhea appeared to be higher in this group. Antibiotic treatment was associated with CKP colonization, whereas patients´ age, gender, Barthel index at admission, and residence with a CKP-colonized roommate were not. Diarrhea also seemed to support to distribution of CKP.

CONCLUSIONS

In this small outbreak, antibiotic treatment seemed to be the predominant risk factor for monoclonal transmission of bla _OXA-48 positive CKP.

Multidrug-resistant organisms in refugees: prevalences and impact on infection control in hospitals

Introduction: The refugee crisis is a great challenge to the social and healthcare system in European countries, especially in Germany. An abundance of data has been published on the refugees’ health problems (infections as well as physical diseases and psychiatric problems) and their prevention (i.e., sanitary and vaccination programs). However, data on prevalences of multidrug-resistant organisms (MDRO) in refugees are scarce, although it is known that most refugees are from or travelled through countries with high prevalences of MDRO. This paper presents current data on MDRO colonization of refugees admitted to hospitals, and the impact of screening upon admission and infection control in hospitals is discussed.

Methods: Anonymous data obtained by screening upon hospital admission were reported by hospitals in the Rhine-Main region of Germany to the local public health department. Screening and microbiological analyses were performed from December 2015 to March 2016 according to standardized and validated methods.

Results: 9.8% of the refugees screened (32/325) exhibited colonization with methicillin-resistant Staphylococcus aureus (MRSA), and 23.3% of the refugees (67/290) were colonized with Gram-negative bacteria with extended spectrum beta-lactamases, and/or enterobacteria with resistance against 3 or 4 groups of antibacterials, so-called 3MRGN (multidrug-resistant Gram-negative bacteria with resistance against penicillins, cephalosporins and quinolones) and 4MRGN (with additional resistance against carbapenems). Carbapenem-resistant Gram-negative bacteria (CRGN) were detected in 2.1% (6/290) of the refugees.

Conclusion: The data confirms the studies published between 2014 and 2016, encompassing refugees tested in Germany, the Netherlands and Israel, with prevalences of MRSA and CRGN up to 13.5% and 5.6%. The MDRO prevalences are higher than those of “risk groups” for MRSA, such as hemodialysis patients and patients depending on outpatient home-nursing care or residing in nursing homes. Therefore, screening and special infection control in hospitals is strongly suggested when refugees are admitted to hospitals, in order to ensure best medical practice and safety for all hospital patients regardless of their country of origin.