[Procalcitonin: The Ideal Biomarker To Guide Initiation, Change and Withdrawal of Antibiotics in Septic Burn Patients?] / La Procalcitonine: Biomarqueur De Choix Pour Guider L'Initiation, La Modification Et L'Arrêt De L'Antibiothérapie Chez Les Brûlés Sepitques?

The goal of this study was to assess plasma procalcitonin (PCT) concentrations during infectious events of burns in the ICU. We conducted a prospective, observational study in a 20-bed Burn Intensive Care Unit in Tunisia. A total of 120 septic patients admitted to the Burn ICU were included in our study. Sepsis was assumed according to the French Burn Association criteria for the presence of infection. Serum PCT was measured over the entire septic episode every 48 hours until resolution of infection, based on clinical signs and decrease of PCT of about 80% compared to its initial value. Patients were assigned to two groups depending on clinical course and outcome: Group A = patients with favourable evolution; Group B = patients with unfavourable evolution. Monitoring of kinetics of PCT allowed us to judge the effectiveness of the initial antibiotic therapy, with a threshold of 43.5% decrease at day 3 of treatment, with a better sensitivity and specificity of 79.6% and 87.7% respectively. In addition, PCT monitoring allowed a reduction in the duration of antibiotic therapy of 5±2.8 days versus 8 to 10 days before the use of PCT.

Colonisation Et Infection À Acinetobacter Baumannii Dans Une Unité De Réanimation Des Brûlés En Tunisie.

Acinetobacter baumannii is a feared pathogen in the burn center due to its opportunistic nature and its multidrug resistance. Our purpose was to study the incidence density of Acinetobacter baumannii colonization and infection and to determine the antibiotic susceptibility of the strains isolated in patients hospitalized in the Trauma and Burn Center Burn Unit in Tunisia. Our retrospective study included 1517 non-repetitive strains of Acinetobacter baumannii, between January 2012 and September 2020, with an average rate of 12.2% of the service's bacterial ecology. The incidence density of Acinetobacter baumannii colonization and infection was 13.7‰ days of in-patient stay and 14.1‰ days of in-patient stay, respectively. A positive and statistically significant correlation between Acinetobacter baumannii colonization and infection (rs=0,7; p=0.005) was noted in our study. The colonization strains were mainly isolated from central catheters (71.2%) and skin swab samples (22.9%). Infections were dominated by bacteremia (47.6%) and respiratory tract infections (25.4%). Bacteremia was microbiologically documented in 53% of cases. The most common source of bacteremia was central catheters (60.8%), skin (22.2%) and respiratory tract (15.5%). The rates of resistance inAcinetobacter baumannii to the antimicrobial agents tested were high: ceftazidime (85.2%), pipéracillin-tazobactam (95.6%), imipenem (95.3%), amikacine (91.1%), ciprofloxacin (93.5%), rifampicin (36.4%) and cotrimoxazole (88.1%). The resistance of colistin was noted in 1.8% of cases.

Corrélation Entre La Consommation D'Antibiotiques Et Les Taux D'Antibiorésistance Chez P. Æruginosa Dans Un Service De Réanimation Des Brûlés Tunisien: Étude Sur 6 Ans (2014-2019).

Antibiotics are one of the greatest advances in modern medicine. Antibiotic resistance is one of the most serious threats to global health, aggravating the prognosis of immunocompromised patients, especially burn patients. Our objective was to study the consumption of antibiotics of critical importance according to the WHO and the correlation between antibiotic resistance in Pseudomonas æruginosa and the consumption of these antibiotics. Our study took place in the Medical Laboratory in collaboration with the Trauma and Burn Center's Burn Unit in Tunisia. In our retrospective study, 1384 non-repetitive strains of Pseudomonas æruginosa responsible for colonization or infection were included, between January 2012 and December 2019. Pseudomonas æruginosa was the most isolated bacterial strain in the service, with an average rate of 15.9% of the service's bacterial ecology. The antibiotic resistance rates tested were high: 77.1% to piperacillin-tazobactam, 56% to ceftazidime, 74.9% to imipenem, 78.8% to amikacin, 54.7% to ciprofloxacin and 32.8% to fosfomycin. Among our strains, 81.8% were multi drug-resistant strains. The analysis of the correlation between the level of consumption of antibiotics and the antibiotic resistance levels in Pseudomonas æruginosa showed that the increased consumption of piperacillin-tazobactam increased resistance not only to piperacillin-tazobactam but also to imipenem and amikacin as well as multi drug resistance. Similarly, the increase in the consumption of fosfomycin correlates with resistance to piperacillin-tazobactam and imipenem.

Hypernatremia Risk Factors And Prognostic Impact In Burn Patients: A Case Control Study.

Hypernatremia is associated with poor outcomes in critically ill patients. Hypernatremia risk factors in burned patients are not well studied. We aimed to identify hypernatremia risk factors and to evaluate outcomes in burned patients admitted to our burns intensive care unit. A case control study was conducted in adult burned patients hospitalized between January 1st 2017 and December 31st 2019. Cases who developed hypernatremia (>145 meq/L) during hospitalization were matched 1:1 with controls based on age and total burn surface area. There were 57 cases and 57 controls with a mean age of 41 ± 18 years. The majority of patients had major burns (n=99, 86.8%). The time onset of hypernatremia was seven days post burn. Compared to controls, the case group mostly consisted of transferred patients with longer time from injury to intensive care unit admission. Inhalation injury, mechanical ventilation, intravenous fosfomycin and colistin were associated with hypernatremia. Admission to the intensive care unit after six hours post-burn was the independent risk factor (OR=4.5). Hypernatremia was associated with longer length of stay and with higher mortality. We conclude that delayed management, inhalation injury, mechanical ventilation, fosfomycin and colistin administration are the main hypernatremia risk factors in burned patients.

L'hypernatrémie est un paramètre pronostic défavorable chez les patients de réanimation. Ses facteurs de risque n'ont pas été bien étudiés chez les brûlés. Nos objectifs étaient d'identifier les facteurs de risque d'hypernatrémie et d'évaluer son impact sur le pronostic des brûlés hospitalisés dans notre unité de réanimation. Une étude cas-témoins a été menée chez des brûlés hospitalisés entre le 1er janvier 2017 et le 31 décembre 2019. Les cas (hypernatrémie >145 meq/L pendant l'hospitalisation) ont été appariés 1/1 avec des témoins, en tenant compte de l'âge et de la surface brûlée. Nous avons colligé 57 cas et 57 témoins âgés de 41±18 ans. La plupart des patients (n=99 soit 86,8%) souffraient de brûlures étendues. L'hypernatrémie s'est installée après sept jours des brûlures. Les cas avaient plus souvent été transférés d'une autre institution et étaient pris en charge dans le service après un délai plus long. Les lésions d'inhalation, la ventilation mécanique, la fosfomycin et la colimycine étaient les facteurs de risque d'hypernatrémie. L'admission en réanimation au-delà de six heures en était le facteur de risque indépendant (OR=4,5). L'hypernatrémie était associée à une durée de séjour plus longue et à une mortalité plus élevée. Nous concluons que la prise en charge tardive, les lésions d'inhalation, la ventilation mécanique, la fosfomycine et la colimycine sont les facteurs de risque d'hypernatrémie chez les brûlés.

Bactériémies Nosocomiales: Épidémiologie Clinique Et Bactériologique Chez Les Brûlés.

Nosocomial bacteremia (NB) is one of the most severe infections in burns in intensive care units. Their prognosis is worsened with the emergence and spread of multidrug resistant bacteria (MDR). Our retrospective study aimed to investigate clinical and bacteriological characteristics of NB occurring in patients hospitalized in the Trauma and Burn Center's Burn Unit (TBC-BU) in Tunisia, during a 3-year period (2016-2018). We found 261 NB in 216 patients, for a prevalence of 25.7% and an incidence density of 13.4‰ days of in-patient stay. The vast majority (88.9%) of NB occurred during the first 2 weeks of hospitalization. The catheterrelated bacteremia rate was 11.1%. P. æruginosa (20.2%) and A. baumannii (16.8%) were the 2 species most frequently isolated when S. aureus represented only 7.5% of isolates. Resistance rates were high, with 71% of P. æruginosa resistant to ceftazidime, 64% of S. aureus being MRSA, 69,5% of resistance to 3rd generation cephalosporins among Enterobacteriaceae, and colimycin remaining the only regularly active antibiotic (98%) on A. baumannii. The MDR rate was 44%, represented mainly by A. baumannii, ESBL-E and P. æruginosa. The mortality rate due to NB was 25%, with a significantly higher rate of MDR in fatal NB compared to that in NB with favorable outcome (p = 0,000019).

Colonisation Et Infection À Pseudomonas Æruginosa Dans Un Service De Réanimation Des Brûlés: Étude Sur 8 Ans.

Pseudomonas æruginosa (PA) is among the major agents of infection in burns. Multidrug-resistant strains are commonly isolated, which hampers the management of these patients. Our purpose was to study the incidence density of PA colonization and PA infection and to investigate the antibiotic susceptibility of strains isolated in patients hospitalized in the Trauma and Burn Center's Burn Unit (TBC-BU) in Tunisia. It is a retrospective study including 1649 non-repetitive strains of PA during an 8-year period (2012- 2019). PA was the most common organism in TBC-BU bacterial ecology (15%). The incidence density of PA colonization and PA infection was 16.1‰ days of in-patient stay (DH) and 16.5‰ DH, respectively. A positive and statistically significant correlation was found between PA colonization and PA infection (rs=1; p=0,004). The colonization strains were mainly isolated from skin (25.1%) and central catheters (22.3%). Bacteremia was the most common infection (19.5%). The skin was the most common source of bacteremia (22.1%) followed by central catheters (18.3%). The highest rates of antibiotic resistance were found with piperacillin-tazobactam (72.4%), ceftazidime (49.4%), meropenem (74%), imipenem (70.5%), amikacin (74.6%), ciprofloxacin (56.5%) and fosfomycin (35.3%). We did not identify any colistin-resistant strain. The multidrug resistance rate was 78%. The metallo-carbapenemase-producing strains rate was 14.4%.

Étude épidémio-clinique des infections à entérobactéries productrices de carbapénémases chez les brûlés.

This study was longitudinal, conducted at the Trauma and Burn Centre between January and June 2017. Its purpose was to determine the prevalence of CPE infection among patients admitted to the Burn Intensive Care Unit, and to study their clinical and biological characteristics. Molecular typing of carbapenemases was performed with PCR type GeneXpert. Thirteen patients were infected with 7 episodes of bacteremia, 2 had ventilator acquired pneumonia and 4 catheter infections, with a prevalence of 7% of admissions. The average length of stay in the intensive care unit prior to infection was 12 days. Antibiotic exposure involved 12 of the 13 patients: 9 patients were transferred from other intensive care units. Thirteen and ten patients were respectively exposed to central catheterization and mechanical ventilation. The predominant carbapenemase among the infecting carbapenemase-producing enterobacteriacae strains was NDM carbapenemase (9/15), with a first description of P. stuartii carrying blaNDM strain in Tunisia. One patient died before adapting antibiotic therapy. For the others, 13 adapted bi-antibiotherapies were prescribed. There were five patient deaths from infection, four of whom had received appropriate antibiotic therapy. Imipenem was used each time the MIC was ≤4mg/l, in combination with another antibiotic: amikacin (3/8), colimycin (4/8), or tigecycline (1/8). Three of these prescriptions resulted in death. The prevalence of carbapenemase-producing enterobacterial infections is high among burn patients with a predominance of NDM-type carbapenemase.

Profil bactériologique et résistance aux antibiotiques des bactéries isolées dans un service de réanimation des brûlés durant sept ans.

This study was retrospective, conducted over seven years at the Trauma and Burn Centre. Its purpose was to establish the bacteriological profile and antibiotic resistance of isolated bacteria in patients admitted to the Burn Intensive Care Unit. Identification was carried out according to the conventional methods and antibiotic susceptibility was analyzed according to the standards of the Antibiogram Committee of the French Society of Microbiology. Pseudomonas aeruginosa was the main isolated bacterium, followed by Staphylococcus aureus, Klebsiella pneumoniae and Acinetobacter baumannii. These strains were isolated mainly from haemocultures (37%). The resistance of Pseudomonas aeruginosa to ceftazidime increased from 9.2% in 2012 to 53.5% in 2018. The resistance to imipenem and ciprofloxacin was 63.3% and 42.9%, respectively. Four strains were resistant to colistin. The resistance of S. aureus to meticillin decreased from 65.3% in 2012 to 41.6% in 2018. All strains were susceptible to glycopeptides, tigecycline and linezolid. A. baumannii was multi-resistant to antibiotics with 81.8% resistance to ceftazidime, 88.9% to amikacin, 90.5% to ciprofloxacin and 94.5% to imipenem. Sixteen strains were resistant to colistin. Concerning K. pneumoniae, 77.5% of strains were resistant to cefotaxime and 5.2% to imipenem. Two strains were resistant to colistin. Vancomycin resistance in Enterococcus faecium increased from 33.4% in 2012 to 72.2% in 2018. Multidrug resistance in burn patients calls for an epidemiological surveillance of bacterial ecology and the application of hygiene measures.

Profil moléculaire et résistance aux antibiotiques des entérobactéries productrices de carbapénèmases chez le brûlé.

Carbapenemase-producing Enterobacteriaceae (CPE) pose an emerging threat worldwide. The purpose of our work was to determine their prevalence among patients hospitalized in the Trauma and Burn Centre's Burn Unit, and to study their microbiological and molecular characteristics. Our study was longitudinal, conducted at the Trauma and Burn Centre's laboratory between January and June 2017. It focused on 42 CPE strains isolated from 34 patients. These strains were made up of K. pneumoniae (24), P. mirabilis (13), K. oxytoca (2), P. stuartii (1), E. coli (1), and E. cloacae (1). The overall prevalence of CPE among Enterobacteriaceae was 14.43% with a monthly decline. The blaNMD gene (59%) predominated on blaOXA-48 (33%) and 7% of strains co-expressed these two genes. We describe the first case of P. stuartii carrying blaNDM in Tunisia. Resistance to ertapenem, imipenem and meropenem was 83%, 57%, and 10% respectively. The antibiotics showing the highest resistant rates were third-generation cephalosporins (97%), gentamicin (98%) and norfloxacin (90%). Colistin and fosfomycin had the best-preserved activity in vitro with 4% and 33% resistance, respectively. The prevalence of EPCs is high among burns. Screening efforts, hygiene measures and the preservation of the few molecules still active are a vital issue.

Description of an original integron encompassing blaVIM-2, qnrVC1 and genes encoding bacterial group II intron proteins in Pseudomonas aeruginosa.

OBJECTIVES: A burn unit of a hospital in Tunis underwent an endemic situation caused by imipenem-resistant Pseudomonas aeruginosa. For nine non-repetitive isolates of a clonal VIM-2-producing strain, the blaVIM-2 genetic background was characterized and the associated qnrVC1 gene molecularly analysed. METHODS: The imipenem resistance mechanism was investigated by phenotypic and molecular tests, and resistance transfer was studied by conjugation and transformation experiments. The integron's structure was characterized by sequencing, and qnrVC1 expression was explored after cloning experiments. RESULTS: The nine VIM-2-producing strains were collected from eight patients and one environmental sample. All transfer assays failed, suggesting a chromosomal location of blaVIM-2. This latter was found to be part of a class 1 integron of ∼7500 bp, which also contains blaOXA-2, aadA1 and two copies of the aadB, arr-6 and qnrVC1 genes. qnrVC1 exhibited higher homology with the chromosomally encoded qnr genes of Vibrionaceae than with plasmid-mediated qnr genes of Enterobacteriaceae. The qnrVC1 gene cassette possesses a promoter allowing its expression, and it conferred decreased fluoroquinolone susceptibility to Escherichia coli. Additionally, on the same integron, genes encoding an uncommon group IIC-attC intron were detected. CONCLUSIONS: A VIM-2-producing P. aeruginosa outbreak led us to characterize an integron harbouring a qnrVC1 cassette and a new group IIC-attC intron. This is the first known description of a qnr determinant in a P. aeruginosa strain. Its presence conferred a low level of resistance to quinolones in E. coli, which might favour the emergence of highly resistant mutants.

Evolution of an incompatibility group IncA/C plasmid harboring blaCMY-16 and qnrA6 genes and its transfer through three clones of Providencia stuartii during a two-year outbreak in a Tunisian burn unit.

During a 2-year period in 2005 and 2006, 64 multidrug-resistant Providencia stuartii isolates, including 58 strains from 58 patients and 6 strains obtained from the same tracheal aspirator, were collected in a burn unit of a Tunisian hospital. They divided into four antibiotypes (ATB1 to ATB4) and three SmaI pulsotypes (PsA to PsC), including 49 strains belonging to clone PsA (48 of ATB1 and 1 of ATB4), 11 strains to clone PsB (7 of ATB2 and 4 of ATB3), and 4 strains to clone PsC (ATB3). All strains, except for the PsA/ATB4 isolate, were highly resistant to broad-spectrum cephalosporins due to the production of the plasmid-mediated CMY-16 ß-lactamase. In addition, the 15 strains of ATB2 and ATB3 exhibited decreased quinolone susceptibility associated with QnrA6. Most strains (ATB1 and ATB3) were gentamicin resistant, related to an AAC(6')-Ib' enzyme. All these genes were located on a conjugative plasmid belonging to the incompatibility group IncA/C(2) of 195, 175, or 100 kb. Despite differences in size and in number of resistance determinants, they derived from the same plasmid, as demonstrated by similar profiles in plasmid restriction analysis and strictly homologous sequences of repAIncA/C(2), unusual antibiotic resistance genes (e.g., aphA-6), and their genetic environments. Further investigation suggested that deletions, acquisition of the ISCR1 insertion sequence, and integron cassette mobility accounted for these variations. Thus, this outbreak was due to both the spread of three clonal strains and the dissemination of a single IncA/C(2) plasmid which underwent a remarkable evolution during the epidemic period.

Clonality of Providencia stuartii isolates involved in outbreak that occurred in a burn unit.

In order to investigate an outbreak of multidrug-resistant Providencia stuartii that occurred in a burn unit, we analyzed by pulsed-field gel electrophoresis (PFGE) all isolates of P. stuartii collected during 4 months of 2005 from patients and from a tracheal aspirator. Seventeen clinical isolates of P. stuartii, extended-spectrum beta-lactamase (ESBL) producing, were collected from 17 patients. All these isolates were nosocomially acquired. Three other isolates were collected from the aspirator probe, the aspirator reservoir and from the aspirator tube. Three different antibiotypes were identified without correlation with the genotype. Two PFGE types were obtained (types A and B) with predominance of one (type A) that was observed for 15 isolates. P. stuartii isolates collected from different components of the aspirator (probe, reservoir and tube) yielded PFGE type A. This study suggests the bi-clonality of the outbreak and that transmission of epidemic P. stuartii isolates was through a common source. The aspirator probe, contaminated from aspirator that functioned as a reservoir of bacteria, seems to be the route of transmission of P. stuartii. Furthermore, this study shows the utility of PFGE in typing for the purpose of understanding the epidemiological behaviour of P. stuartii and as a basis for the development of rational control strategies.

[Implementation of antimicrobial resistance surveillance and antibiotic consumption in an intensive care burn department]. / Mise en place d'une surveillance de la résistance et de la consommation des antibiotiques dans un service de réanimation de brûlés.

BACKGROUND: The increasing consumption of antibiotics in hospitals and the economic implications of this increase lead to survey this consumption in the various hospital units. AIM: Our study proposes to measure the annual antibiotic use and antimicrobial resistance in an intensive care Burn department in order to manage the control measures. METHODS: The study was conducted during a 5 year period (1 January 2000 to 31 December 2004). The average number of admissions was 204/year and the mean number of hospitalisation was 4036/year. Antimicrobial susceptibility testing was performed by disk diffusion method. Susceptibility testing data were stored in a laboratory data base using whonet 5.3 software. The consumption of following antibiotics: imipenem, ceftazidime, ofloxacin, ciprofloxacin, piperacillin-tazobactam was measured by antimicrobial density (AD) witch takes into account the quantity of antibiotics in Grams converted to daily defined dose (DDD) and number of hospitalization days. The daily defined dose (DDD) was proposed by WHO. The calculation of the AD for each molecule was earned Out according to the following formula: AD = (Quality consumed in for the particular antimicrobial x 1000) / (DDD for that antimicrobial x number of days of hospitalizations). RESULTS: There was statistically significant relationship between increasing use of ceftazidime and ceftazidime resistant Klebsiella pneumoniae (rs = 0.93; p = 0.O2) The use of ceftazidime was not significantly associated with resistance to this molecule in P. aeruginosa (rs = 0.76 p = 0.13). Conceerning the fluoroquinolones, there was statistically significant relation ship between increasing use of ciprofloxacin and rate ciprofloxacin resistant P. aeruginosa (rs = 0.89, P = 0.043). Furthermore, the consumption of ciprofloxacin was significantly correlated to imipenem resistance in P. aeruginosa (rs = 0.87, p = 0.05). However, the consumption of imipenem was not significantly correlated to resistance of this drug in P. aeruginosa (rs = 0.45; P = 0.4). CONCLUSION: The monitoring of both antibiotic consumption and antibiotic resistance is necessary to set up targeted policies and to control their effectiveness. Nevertheless this monitoring must be integrated into global policy of good use and control of antibiotics.

[Not Available]. / Etiologie Rare de Sinusites Nosocomiales en Milieu de Reanimation - A Propos d'une Observation.

Les sinusites nosocomiales ne sont pas rares en réanimation. Elles surviennent en général dans les suites d'une intubation nasotrachéale voire même orotrachéale. Le tubage gastrique peut être à lui seul à l'origine d'une sinusite nosocomiale. Nous rapportons le cas d'une patiente hospitalisée qui a été victime de brûlures étendues chez qui la sonde nasogastrique a été à l'origine d'une pansinusite dont l'issue a été fatale.