Christian De TYMOWSKI

Christian De TYMOWSKI


Research Focus & Metrics

Academic Career Length

6Years (2021-Present)

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

Representative Publications

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18 January 2024 in Antibiotics
Verified
Journal Article
Open access
PDF file
EAEnora Atchade
Enora Atchade
CTChristian De TYMOWSKI
Christian De TYMOWSKI
NGNathalie Grall
Nathalie Grall
STSébastien Tanaka
Sébastien Tanaka
PMphilippe montravers
philippe montravers
Toxic shock syndrome (TSS) is a rare, life-threatening, toxin-mediated infectious process linked, in the vast majority of cases, to toxin-producing strains of Staphylococcus aureus or Streptococcus pyogenes. The pathophysiology, epidemiology, clinical presentation, microbiological features, management and outcome of TSS are described in this review. Bacterial superantigenic exotoxins induces unconventional polyclonal lymphocyte activation, which leads to rapid shock, multiple organ failure syndrome, and death. The main described superantigenic exotoxins are toxic shock syndrome toxin—1 (TSST-1) and enterotoxins for Staphylococcus aureus and Streptococcal pyrogenic exotoxins (SpE) A, B, and C and streptococcal superantigen A (SsA) for Streptococcus pyogenes. Staphylococcal TSS can be menstrual or nonmenstrual. Streptococcal TSS is linked to a severe group A streptococcal infection and, most frequently, to a necrotizing soft tissue infection. Management of TSS is a medical emergency and relies on early detection, immediate resuscitation, source control and eradication of toxin production, bactericidal antibiotic treatment, and protein synthesis inhibiting antibiotic administration. The interest of polyclonal intravenous immunoglobulin G administration as an adjunctive treatment for TSS requires further evaluation. Scientific literature on TSS mainly consists of observational studies, clinical cases, and in vitro data; although more data on TSS are required, additional studies will be difficult to conduct due to the low incidence of the disease.

4 January 2023 in Antibiotics
Verified
Journal Article
Open access
PDF file
CTChristian De TYMOWSKI
Christian De TYMOWSKI
TSTarek Sahnoun
Tarek Sahnoun
SPSophie Provenchere
Sophie Provenchere
MPMarylou Para
Marylou Para
NDNicolas Derre
Nicolas Derre
PMphilippe montravers
philippe montravers
(1) Background: Cephalosporins (CA) are the first-line antibiotic prophylaxis recommended to prevent surgical site infection (SSI) after cardiac surgery. The combination of vancomycin/gentamicin (VGA) might represent a good alternative, but few studies have evaluated its efficacy in SSI prevention. (2) Methods: A single-centre retrospective study was conducted over a 13-year period in all consecutive adult patients undergoing elective cardiac surgery. Patients were stratified according to the type of antibiotic prophylaxis. CA served as the first-line prophylaxis, and VGA was used as the second-line prophylaxis. The primary endpoint was SSI occurrence at 90 days, which was defined as the need for reoperation due to SSI. (3) Results: In total, 14,960 adult patients treated consecutively from 2006 to 2019 were included in this study, of whom 1774 (12%) received VGA and 540 (3.7%) developed SSI. VGA patients had higher severity with increased 90-day mortality. Nevertheless, the frequency of SSI was similar between CA and VGA patients. However, the microbiological aetiologies were different, with more Gram-negative bacteria noted in the VGA group. (4) Conclusions: VGA seems to be as effective as CA in preventing SSI.

4 September 2024 in Critical Care
Verified
Journal Article
Open access
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CKChristian Kassasseya
Christian Kassasseya
LTLigia Iulia Torsin
Ligia Iulia Torsin
CMCaroline Musset
Caroline Musset
MBMarc Benhamou
Marc Benhamou
ICIrshad H. Chaudry
Irshad H. Chaudry
CTChristian De TYMOWSKI
Christian De TYMOWSKI
Experimental studies in animals have yielded conflicting results on the role of Tumor Necrosis Factor (TNF) in sepsis and endotoxemia, with some reporting adaptive and others inappropriate effects. A meta-analysis of the available literature was performed to determine the factors explaining this discrepancy. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. The protocol was registered with PROSPERO (CRD42020167384) prior to data collection. PubMed and Embase were the databases queried. Risk of bias was evaluated using the SYRCLE Risk of Bias Tool. All animal studies investigating sepsis-related mortality and modified TNF signaling were considered eligible. The exclusion criteria were: lack of mortality data, 7-day mortality rates below 10% in both wild type and TNF-altered pathway animals, and absence of an English To determine the role of TNF according to the experimental protocol, three approaches were used: first an approach based on the statistical significance of each experiment, then the pooled mortality was calculated, and finally the weighted risk ratio for mortality was assessed. A total of 175 studies were included in the analysis, comprising a total of 760 experiments and involving 19,899 animals. The main species used were mice (77%) and rats (21%). The most common method of TNF pathway modulation was TNF pathway inactivation that was primarily associated with an inappropriate secretion of TNF. At the opposite, TNF injection was associated with an adaptive role of TNF. Lipopolysaccharide (LPS) injection was the most used stimulus to establish an infectious model (42%) and was strongly associated with an inappropriate role of TNF. Conversely, live bacterial models, especially the cecal ligation and puncture (CLP) model, pneumonia, meningitis, and gastrointestinal infection, were associated with an adaptive role. This was particularly evident for Listeria monocytogenes, Streptococcus pneumoniae. The role of TNF during infection varies depending on the experimental model used. Models that mimic clinical conditions, based on virulent bacteria that cause high mortality even at low inocula, demonstrated an adaptive role of TNF. Conversely, models based on LPS or low-pathogenic live bacteria, administered at doses well above physiological thresholds and combined with early antibiotic therapy, were associated with an inappropriate role.

3 April 2024 in BMC Pulmonary Medicine
Verified
Journal Article
Open access
PDF file
EAEnora Atchade
Enora Atchade
CTChristian De TYMOWSKI
Christian De TYMOWSKI
ELE. Lepitre
E. Lepitre
NZN. Zappella
N. Zappella
ASA. Snauwaert
A. Snauwaert
PMP. Montravers
P. Montravers
Background: Prior studies have assessed the impact of the pretransplantation recipient body mass index (BMI) on patient outcomes after lung transplantation (LT), but they have not specifically addressed early postoperative complications. Moreover, the impact of donor BMI on these complications has not been evaluated. The first aim of this study was to assess complications during hospitalization in the ICU after LT according to donor and recipient pretransplantation BMI. Methods: All the recipients who underwent LT at Bichat Claude Bernard Hospital, Paris, between January 2016 and August 2022 were included in this observational retrospective monocentric study. Postoperative complications were analyzed according to recipient and donor BMIs. Univariate and multivariate analyses were also performed. The 90-day and one-year survival rates were studied. P < 0.05 was considered to indicate statistical significance. The Paris-North Hospitals Institutional Review Board approved the study. Results: A total of 304 recipients were analyzed. Being underweight was observed in 41 (13%) recipients, a normal weight in 130 (43%) recipients, and being overweight/obese in 133 (44%) recipients. ECMO support during surgery was significantly more common in the overweight/obese group (p = 0.021), as were respiratory complications (primary graft dysfunction (PGD) (p = 0.006), grade 3 PDG (p = 0.018), neuroblocking agent administration (p = 0.008), prone positioning (p = 0.007)), and KDIGO 3 acute kidney injury (p = 0.036). However, pretransplantation overweight/obese status was not an independent risk factor for 90-day mortality. An overweight or obese donor was associated with a decreased PaO2/FiO2 ratio before organ donation (p < 0.001), without affecting morbidity or mortality after LT. Conclusion: Pretransplantation overweight/obesity in recipients is strongly associated with respiratory and renal complications during hospitalization in the ICU after LT.

1 August 2021 in Anaesthesia Critical Care & Pain Medicine
Verified
Journal Article
Closed access
QRQuentin de Roux
Quentin de Roux
SPSophie Provenchere
Sophie Provenchere
DLDan Longrois
Dan Longrois
CTChristian De TYMOWSKI
Christian De TYMOWSKI

20 October 2026 in European Journal of Anaesthesiology
Verified
Journal Article
Open access
SAStefan Andrei
Stefan Andrei
SPSophie Provenchère
Sophie Provenchère
ABAnne Boutten
Anne Boutten
KBKevin Boussion
Kevin Boussion
TSTarek Sahnoun
Tarek Sahnoun
CTChristian De TYMOWSKI
Christian De TYMOWSKI
BACKGROUND: Vancomycin combined with gentamicin (VGA) is used as an alternative antibiotic prophylaxis in cardiac surgery when cephalosporins are contraindicated. However, the nephrotoxic potential of this combination raises concerns regarding postoperative acute kidney injury (AKI). OBJECTIVE: This study aimed to evaluate the association between VGA prophylaxis and AKI occurrence in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB), while accounting for preoperative risk factors. DESIGN: Retrospective single-centre study. AKI was defined according to KDIGO criteria within 7 postoperative days. PATIENTS: Of the 8895 eligible patients between April 2013 and December 2021, 8198 were included. Subgroup analyses were performed according to preoperative AKI risk status (high-risk: insulin-dependent diabetes, cirrhosis, acute endocarditis, preoperative critical state, emergency surgery, or cardiac transplantation). RESULTS: In our cohort, 7469 (91%) received cephalosporins and 729 (9%) received VGA. The overall AKI incidence was 16%. AKI occurred more frequently in the VGA group (29% vs. 15%, P < 0.001). After multivariable adjustment, VGA remained independently associated with AKI [odds ratio (OR) 1.29, 95% confidence interval (CI) 1.03 to 1.62, P = 0.024], confirmed by propensity score analysis (OR 1.32, 95% CI 1.09 to 1.60, P = 0.005). In subgroup analyses, VGA was significantly associated with AKI in high-risk patients (OR 1.53, 95% CI 1.14 to 2.04, P = 0.004), but not in low-risk patients (OR 1.19, 95% CI 0.87 to 1.64, P = 0.285). CONCLUSION: In this large retrospective cohort, VGA antibiotic prophylaxis was independently associated with increased AKI risk following cardiac surgery with CPB. This association was driven primarily by patients with preoperative risk factors for AKI. Alternative prophylactic regimens should be considered in high-risk patients when possible.