Tobias Siegfried Kramer

Dr. Tobias Siegfried Kramer

orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2019 in Journal of Infection
Verified
Journal Article
Closed access
MWMarjan Wouthuyzen-Bakker
Marjan Wouthuyzen-Bakker
MSMarine Sebillotte
Marine Sebillotte
JLJose Lomas
Jose Lomas
ATAdrian Taylor
Adrian Taylor
EBEva Benavent
Eva Benavent
ASAlex Soriano
Alex Soriano

24 April 2018 in Antimicrobial Resistance & Infection Control
Verified
Journal Article
Open access
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CRCornelius Remschmidt
Cornelius Remschmidt
CSChristin Schröder
Christin Schröder
MBMichael Behnke
Michael Behnke
PGPetra Gastmeier
Petra Gastmeier
CGChristine Geffers
Christine Geffers
TKTobias Siegfried Kramer
Tobias Siegfried Kramer
Background: Enterococci are frequent pathogens causing nosocomial infections in Germany. Infections due to strains with vancomycin resistance are high when compared with other European states. Therefore, the study aimed to describe the recent progression of nosocomial infections due to vancomycin-resistant enterococci (VRE) in Germany. Methods: We analyzed data from two components of the German national nosocomial infection surveillance system for the period 2007–2016. For primary bloodstream infections (BSIs) and urinary tract infections (UTIs) we used data from intensive care units and for surgical site infections (SSIs) data from surgical departments. In a sensitivity analysis, we considered only data from participants that participated continuously from 2007 to 2016 (“core group”). We calculated proportions of VRE among all nosocomial enterococcal infections with 95% confidence intervals (95% CIs) and trends over time. A multivariable logistic regression was used to compare occurrence of VRE proportions among German federal states. Results: Enterococcal infections from 857 ICUs and 1119 surgical departments were analyzed. On ICUs, the proportion of vancomycin resistance in enterococci causing nosocomial infections significantly increased for BSIs from 5.9 to 16.7% and for UTIs from 2.9 to 9.9%; for surgical site infections, the proportion of VRE increased from 0.9 to 5.2% (P < 0.001 for all). In the core group, the increase of VRE was more pronounced in ICUs (BSIs: 5.5 to 21.6%; UTIs: 2 to 11.2%) but was not seen in surgical departments (SSIs: 1.5 to 2.8%). Compared with the most populous German federal state North Rhine Westphalia, enterococcal infections in Hesse (Odds Ratio (OR) 2.3, 95% CI 1.7–3.1), Saxony (OR 2.5, 95% CI 1.8–3.5) and Thuringia (OR 1.9, 95% CI 1.4–2.6) were more likely to be caused by vancomycin-resistant strains. Conclusion: In Germany, the proportion of VRE in nosocomial infection due to enterococci is still increasing. It remains unclear, why a large variation in the proportion of VRE exists between German federal states.

14 November 2018 in Antimicrobial Resistance & Infection Control
Verified
Journal Article
Open access
PDF file
TKTobias Siegfried Kramer
Tobias Siegfried Kramer
CRCornelius Remschmidt
Cornelius Remschmidt
SWSven Werner
Sven Werner
MBMichael Behnke
Michael Behnke
FSFrank Schwab
Frank Schwab
RLRasmus Leistner
Rasmus Leistner
Background: Infections caused by vancomycin-resistant enterococci (VRE) are on the rise worldwide. Few studies have tried to estimate the mortality burden as well as the financial burden of those infections and found that VRE are associated with increased mortality and higher hospital costs. However, it is unclear whether these worse outcomes are attributable to vancomycin resistance only or whether the enterococcal species (Enterococcus faecium or Enterococcus faecalis) play an important role. We therefore aimed to determine the burden of enterococci infections attributable to vancomycin resistance and pathogen species (E. faecium and E. faecalis) in cases of bloodstream infection (BSI). Methods: We conducted a retrospective cohort study on patients with BSI caused by Enterococcus faecium or Enterococcus faecalis between 2008 and 2015 in three tertiary care hospitals. Data was collected on true hospital costs (in €), length of stay (LOS), basic demographic parameters, and underlying diseases including the results of the Charlson comorbidity index (CCI). We used univariate and multivariable regression analyses to compare risk factors for in-hospital mortality and length of stay (i) between vancomycin-susceptible E. faecium- (VSEm) and vancomycin-susceptible E. faecalis- (VSEf) cases and (ii) between vancomycin-susceptible E. faecium- (VSEm) and vancomycin-resistant E. faecium-cases (VREm). We calculated total hospital costs for VSEm, VSEf and VREm. Results: Overall, we identified 1160 consecutive cases of BSI caused by enterococci: 596 (51.4%) cases of E. faecium BSI and 564 (48.6%) cases of E. faecalis BSI. 103 cases of E. faecium BSI (17.3%) and 1 case of E. faecalis BSI (0.2%) were infected by vancomycin-resistant isolates. Multivariable analyses revealed (i) that in addition to different underlying diseases E. faecium was an independent risk factor for in-hospital mortality and prolonged hospital stay and (ii) that vancomycin-resistance did not further increase the risk for the described outcomes among E. faecium-isolates. However, the overall hospital costs were significantly higher in VREm-BSI cases as compared to VSEm- and VSEf-BSI cases (80,465€ vs. 51,365€ vs. 31,122€ p < 0.001). Conclusion: Our data indicates that in-hospital mortality and infection-attributed hospital stay in enterococci BSI might rather be influenced by Enterococcus species and underlying diseases than by vancomycin resistance. Therefore, future studies should consider adjusting for Enterococcus species in addition to vancomycin resistance in order to provide a conservative estimate for the burden of VRE infections.

4 May 2018 in BMC Infectious Diseases
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Journal Article
Open access
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OGon behalf of the RAI-Study Group
on behalf of the RAI-Study Group
FSFlorian Salm
Florian Salm
SSSandra Schneider
Sandra Schneider
KSKatja Schmücker
Katja Schmücker
IPInga Petruschke
Inga Petruschke
JGJochen Gensichen
Jochen Gensichen
This study investigates the barriers and facilitators of the use of antibiotics in acute respiratory tract infections by general practitioners (GPs) in Germany. A multidisciplinary team designed and pre-tested a written questionnaire addressing the topics awareness of antimicrobial resistance (7 items), use of antibiotics (9 items), guidelines/sources of information (9 items) and sociodemographic factors (7 items), using a five-point-Likert-scale (“never” to “very often”). The questionnaire was mailed by postally to 987 GPs with registered practices in eastern Germany in May 2015. 34% (340/987) of the GPs responded to this survey. Most of the participants assumed a multifactorial origin for the rise of multidrug resistant organisms. In addition, 70.2% (239/340) believed that their own prescribing behavior influenced the drug-resistance situation in their area. GPs with longer work experience (> 25 years) assumed less individual influence on drug resistance than their colleagues with less than 7 years experience as practicing physicians (Odds Ratio [OR] 0.32, 95% Confidence Interval [CI] 0.17–0.62; P < 0.001). 99.1% (337/340) of participants were familiar with the “delayed prescription” strategy to reduce antibiotic prescriptions. However, only 29.4% (74/340) answered that they apply it “often” or “very often”. GPs working in rural areas were less likely than those working in urban areas to apply delayed prescription. The knowledge on factors causing antimicrobial resistance in bacteria is good among GPs in eastern Germany. However measures to improve rational prescription are not widely implemented yet. Further efforts have to be made in order to improve rational prescription of antibiotic among GPs. Nevertheless, there is a strong awareness of antimicrobial resistance among the participating GPs.

1 March 2019 in Journal of Infection
Verified
Journal Article
Closed access
TKTobias Siegfried Kramer
Tobias Siegfried Kramer
CSC. Schröder
C. Schröder
MBM. Behnke
M. Behnke
SASeven Johannes Sam Aghdassi
Seven Johannes Sam Aghdassi
CGC. Geffers
C. Geffers
CRC. Remschmidt
C. Remschmidt

2 March 2023 in Eurosurveillance
Verified
Journal Article
Open access
PBPeter Bischoff
Peter Bischoff
TKTobias Siegfried Kramer
Tobias Siegfried Kramer
CSChristin Schröder
Christin Schröder
MBMichael Behnke
Michael Behnke
FSFrank Schwab
Frank Schwab
SASeven Johannes Sam Aghdassi
Seven Johannes Sam Aghdassi
Background: Older age is frequently cited as a risk factor for healthcare-associated infections in general, and surgical site infections (SSIs) specifically. Aim: We aimed to investigate the correlation between age and SSI occurrence. Methods: Data on total hip replacement (THR) and total knee replacement (TKR) surgeries and resulting SSIs documented in the German national surveillance network from a 10-year period from 2009 to 2018 were selected for analysis. SSI rates and adjusted odds ratios (AOR) were calculated and a multivariable analysis to determine risk factors for SSI occurrence was conducted. Results: A total of 418,312 THR procedures resulting in 3,231 SSIs, and 286,074 TKR procedures with 1,288 SSIs were included in the analyses. For THR, SSI rates were higher in older age groups when compared with the reference age group of 61–65 years. A significantly higher risk was observed in the 76–80 years age group (AOR: 1.21, 95% CI: 1.05–1.4). An age of ≤ 50 years was associated with a significantly lower SSI risk (AOR: 0.64, 95% CI: 0.52–0.8). For TKR, a similar correlation was observed, with the exception of the youngest age group (≤ 52 years), which was shown to have an SSI risk equal to that of the knee prosthesis reference age group (78–82 years). Conclusion: A strong correlation between increasing age and SSI occurrence was observed for both procedure types. The results of our analyses provide a basis to consider future targeted SSI prevention measures for different age groups.