Characteristics of Gram-positive cocci infection and the therapeutic effect after liver transplantation / 中南大学学报(医学版)

OBJECTIVES@#Gram-positive cocci is the main pathogen responsible for early infection after liver transplantation (LT), posing a huge threat to the prognosis of liver transplant recipients. This study aims to analyze the distribution and drug resistance of Gram-positive cocci, the risk factors for infections and efficacy of antibiotics within 2 months after LT, and to guide the prevention and treatment of these infections.@*METHODS@#In this study, data of pathogenic bacteria distribution, drug resistance and therapeutic efficacy were collected from 39 Gram-positive cocci infections among 256 patients who received liver transplantation from donation after citizens' death in the Third Xiangya Hospital of Central South University from January 2019 to July 2022, and risk factors for Gram-positive cocci infection were analyzed.@*RESULTS@#Enterococcus faecium was the dominant pathogenic bacteria (33/51, 64.7%), followed by Enterococcus faecalis (11/51, 21.6%). The most common sites of infection were abdominal cavity/biliary tract (13/256, 5.1%) and urinary tract (10/256, 3.9%). Fifty (98%) of the 51 Gram-positive cocci infections occurred within 1 month after LT. The most sensitive drugs to Gram-positive cocci were teicoplanin, tigecycline, linezolid and vancomycin. Vancomycin was not used in all patients, considering its nephrotoxicity. Vancomycin was not administered to all patients in view of its nephrotoxicity.There was no significant difference between the efficacy of daptomycin and teicoplanin in the prevention of cocci infection (P>0.05). Univariate analysis indicated that preoperative Model for End-Stage Liver Disease (MELD) score >25 (P=0.005), intraoperative red blood cell infusion ≥12 U (P=0.013) and exposure to more than 2 intravenous antibiotics post-LT (P=0.003) were related to Gram-positive cocci infections. Multivariate logistic regression analysis revealed that preoperative MELD score >25 (OR=2.378, 95% CI 1.124 to 5.032, P=0.024) and intraoperative red blood cell transfusion ≥ 12 U (OR=2.757, 95% CI 1.227 to 6.195, P=0.014) were independent risk factors for Gram-positive cocci infections after LT. Postoperative Gram-positive cocci infections were reduced in LT recipients exposing to more than two intravenous antibiotics post-LT (OR=0.269, 95% CI 0.121 to 0.598, P=0.001).@*CONCLUSIONS@#Gram-positive cocci infections occurring early after liver transplantation were dominated by Enterococcus faecalis infections at the abdominal/biliary tract and urinary tract. Teicoplanin, tigecycline and linezolid were anti-cocci sensitive drugs. Daptomycin and teicoplanin were equally effective in preventing cocci infections due to Gram-positive cocci. Patients with high preoperative MELD score and massive intraoperative red blood cell transfusion were more likely to suffer Gram-positive cocci infection after surgery. Postoperative Gram-positive cocci infections were reduced in recipients exposing to more than two intravenous antibiotics post-LT.

Synergistic effect of β-thujaplicin and tigecycline against tet(X4)-positive Escherichia coli in vitro / 生物工程学报

The widespread of tigecycline resistance gene tet(X4) has a serious impact on the clinical efficacy of tigecycline. The development of effective antibiotic adjuvants to combat the looming tigecycline resistance is needed. The synergistic activity between the natural compound β-thujaplicin and tigecycline in vitro was determined by the checkerboard broth microdilution assay and time-dependent killing curve. The mechanism underlining the synergistic effect between β-thujaplicin and tigecycline against tet(X4)-positive Escherichia coli was investigated by determining cell membrane permeability, bacterial intracellular reactive oxygen species (ROS) content, iron content, and tigecycline content. β-thujaplicin exhibited potentiation effect on tigecycline against tet(X4)-positive E. coli in vitro, and presented no significant hemolysis and cytotoxicity within the range of antibacterial concentrations. Mechanistic studies demonstrated that β-thujaplicin significantly increased the permeability of bacterial cell membranes, chelated bacterial intracellular iron, disrupted the iron homeostasis and significantly increased intracellular ROS level. The synergistic effect of β-thujaplicin and tigecycline was identified to be related to interfere with bacterial iron metabolism and facilitate bacterial cell membrane permeability. Our studies provided theoretical and practical data for the application of combined β-thujaplicin with tigecycline in the treatment of tet(X4)-positive E. coli infection.

Resistencia a colistina en aislados de Klebsiella pneumoniae resistente a carbapenémicos en un hospital pediátrico de Corrientes / Colistin resistance in carbapenem-resistant Klebsiella pneumoniae isolates from a pediatric hospital from Corrientes, Argentina

INTRODUCCIÓN: Existe un incremento de las infecciones por Klebsiella pneumoniae resistente a carbapenémicos (KPRC) en la población pediátrica y los datos epidemiológicos son limitados. OBJETIVOS: Conocer la frecuencia de KPRC en pacientes pediátricos, determinar la actividad in vitro de colistina y detectar el gen mcr-1 en dichos aislados. MATERIALES Y MÉTODOS: Se estudiaron 220 aislados de K. pneumoniae en un hospital pediátrico durante los años 2018 y 2019. La susceptibilidad antimicrobiana se determinó por microdilución en caldo según CLSI y EUCAST. Los genes blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-48 y mcr-1 se analizaron mediante reacción de polimerasa en cadena (RPC). RESULTADOS: El 9,5% (n: 21) de los aislados fueron caracterizados como KPRC, donde se observó una resistencia a colistina de 47,6% (10/21) con valores de CIM50 de 2 μg/mL y CIM90 de > 4 μg/mL. En todos los aislados de KPRC se caracterizó el gen blaKPC y no se detectó el gen mcr-1. El perfil de resistencia observado en otros antimicrobianos fue el siguiente: gentamicina 100% (n: 21), ciprofloxacina 100% (n: 21), cotrimoxazol 100% (n: 21) y amikacina 19% (n: 4). Se observó 100% de sensibilidad a tigeciclina y ceftazidima/avibactam. CONCLUSIÓN: Este estudio demuestra un valor significativo de la resistencia a colistina en comparación a ceftazidima/avibactam y tigeciclina.

BACKGROUND: There is an increase of carbapenem-resistant Klebsiella pneumoniae (CRKP) infections in the pediatric population and epidemiological data are limited. Aim: To calculate the frequency of CRKP in pediatric patients, to determine the in vitro activity of colistin and to detect the presence of mcr-1 gene in said isolates. METHODS: 220 isolates of K. pneumoniae were studied in a pediatric hospital between January 2018 and December 2019. Antimicrobial susceptibility was determined by microdilution in broth according to guidelines of CLSI and EUCAST. The genes blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-48 and mcr-1 were detected by polymerase chain reaction (PCR). RESULTS: 9.5% (n: 21) of the isolates were characterized as CRKP, where was observed a resistance to colistin of 47.6% (10/21) with values of MIC50 of 2 μg/mL and MIC90 of ≥ 4 μg/mL. In 100% of CRKP strains the blaKPC gene was detected and the mcr-1 gene was not found. The resistance profile to other antimicrobials was as follow: gentamicin 100% (n: 21), trimethoprim/sulfamethoxazole 100% (n: 21), ciprofloxacin 100% (n: 21), amikacin 19% (n: 4). All of the isolates were sensitive to ceftazidime/avibactam and tigecycline. CONCLUSION: This study demonstrates a significant value of resistance to colistin in pediatric patients compared to other last line antimicrobial such as ceftazidime/avibactam and tigecycline.

Use of tigecycline at a teaching hospital / Uso da tigeciclina em hospital de ensino

INTRODUCTION: Tigecycline is an antimicrobial agent, approved for the treatment of complicated skin and soft tissue infections, hospital-acquired and community-acquired pneumonia, intra-abdominal infections and anaerobic or atypical infections. OBJECTIVE: To describe the use of tigecycline in a teaching hospital and to compare data from patients who had their prescriptions audited by the hospital infection committee with those who did not have audited prescriptions. METHODS: Retrospective observational cohort study conducted at a teaching hospital from April 2012 to March 2014 including patients who received tigecycline. Demographic variables, comorbidities, microbiological findings, prescribed antibiotics and technical opinions issued by the Hospital Infection Control Service were collected. RESULTS: 71 patients were included, aged between 13 and 92 years, 63.4% were male and 56.3% were non-white. Tigecycline was the first antimicrobial choice in 19.7% (14/71) of the cases, while the use associated with other antibiotics was observed in 66.2% (45/71) of the prescriptions. mainly with meropenem (28.9%). Empirical use was performed in 69.0% of cases, after culture and the antibiogram in 31.0% and off label use in 81.7%. The microorganisms frequently identified by the culture tests were Enterococcus faecalis (17.6%), Pseudomonas aeruginosa (14.7%) and Klebsiella penumoniae (11.8%). CONCLUSION: The study demonstrated that empirical and off label use is common in clinical practice and few prescriptions were guided by the results of the culture and the antibiogram, demonstrating the need for prescribers to evaluate the benefits/ risks of using this antibiotic, risk of resistance, adverse effects and drug interactions, in addition to cost.

INTRODUÇÃO: A tigeciclina é agente antimicrobiano, aprovada para o tratamento de infecções complicadas na pele e tecidos moles, pneumonia hospitalar e adquirida na comunidade, infecções intra-abdominal e infecções anaeróbias ou atípicas. OBJETIVO: Descrever o uso da tigeciclina em hospital de ensino e comparar dados de pacientes que tiveram suas prescrições auditadas pela comissão de infecção hospitalar com os que não tiveram prescrições auditadas. MÉTODOS: Estudo de coorte retrospectivo observacional realizado em hospital de ensino de abril de 2012 a março de 2014 incluindo pacientes que receberam tigeciclina. Foram coletadas variáveis ​​demográficas, comorbidades, achados microbiológicos, antibióticos prescritos e pareceres técnicos emitidos pelo Serviço de Controle de Infecção Hospitalar. RESULTADOS: Foram incluídos 71 pacientes, com idade entre 13 e 92 anos, 63,4% eram do sexo masculino e 56,3% eram não brancos. A tigeciclina foi primeira escolha antimicrobiana em 19,7% (14/71) dos casos, enquanto o uso associado a outros antibióticos foi observado em 66,2% (45/71) das prescrições. principalmente com meropenem (28,9%). O uso empírico foi realizado em 69,0% dos casos, após cultura e o antibiograma em 31,0% e o uso off label em 81,7%. Os microrganismos frequentemente identificados pelos testes de cultura foram Enterococcus faecalis (17,6%), Pseudomonas aeruginosa (14,7%) e Klebsiella penumoniae (11,8%). CONCLUSÃO: O estudo demonstrou que o uso empírico e off label é comum na prática clínica e poucas prescrições foram orientadas pelos resultados da cultura e do antibiograma, demonstrando necessidade de prescritores avaliarem os benefícios/riscos do uso desse antibiótico, risco de resistência, efeitos adversos e interações medicamentosas, além do custo.

Evolution of the prevalence and antimicrobial resistance among Escherichia coli isolated as a cause of infection in patients admitted to a iv-level hospital in Lima, Peru

The levels and evolution of antimicrobial resistance of Escherichia coli during 01/2009-06/2010 (Period 1), 01/2012-06-2013 (Period 2) and 07/2013-12/2014 (Period 3) were analyzed. Identification, susceptibility levels to 13 antibiotics and the presence of extendedspectrum ß-lactamases (ESBLs) were determined. Overall, 9,918 microorganisms were isolated as a cause of infection. Of these 3,016 (30.4%) were E. coli, with 1,770 (59%), 992 (33%) and 254 (8%), from the Medicine and the Surgery Departments and the Intensive Care Unit (ICU), respectively. There was a significant increase (p=0.0002) of E. coli throughout considered periods. The isolates presented high levels of resistance (>60%) to cephalosporins, ciprofloxacin and cotrimoxazole, being only susceptible to imipenem (0.3% of resistance) and tigecycline. Overall the analysis of evolution of antimicrobial resistance showed that resistance to cephalosporins and amikacin significantly increased, while, the ones of piperacillintazobactam, cotrimoxazole and gentamicin had significantly decreased. Nevertheless, the ICU isolates showed an inverse scenario for cephalosporins. These findings agree with an increase of ESBLs on the Medicine (56% to 66%; p<0.0001) and on the Surgery (54% to 62%; p=0.0197) departments, with a parallel decrease in the ICU (76% to 68%). In summary, high levels of antimicrobial resistance have been reported among E. coli, with worrisome levels of ESBL. A continuous surveillance of antimicrobial resistance levels in the area is needed.

Anti-tumor activity of tigecycline: a review / 生物工程学报

Tigecycline is a novel glycylcycline antibacterial drug, which shows both antibiotic function and anti-tumor activity. This review summarizes the single and combined use of tigecycline for tumor treatment and the underpinning mechanisms. As an inhibitor for mitochondrial DNA translation, tigecycline affects the proliferation, migration, and invasion of tumor cells mainly through inhibiting mitochondrial protein synthesis and inducing mitochondrial dysfunction. Although the effect of tigecycline monotherapy is controversial, the efficacy of combined use of tigecycline is satisfactory. Therefore, it is important to explore the molecular mechanisms underpinning the anti-tumor activity of tigecycline, with the aim to use it as a cheap and effective new anti-tumor drug.

Uso compasional de tigeciclina intraventricular en pacientes con ventriculitis causada por Enterococcus faecium. Reporte de seis casos pediátricos / Compassional use of Intraventricular Tigecycline in ventriculitis caused by Enterococcus faecium. Six pediatric cases

Introducción: La Tigeciclina es un fármaco de uso restringido en pediatría. El uso de este antibiótico por vía intraventricular es una decisión de uso compasivo en casos de bacterias altamente resistentes, y para los casos en que no exista otra alternativa. Caso clínico: Se presenta seis casos de pacientes con diagnóstico de ventriculitis a Enterococcus faecium que recibieron tigeciclina intraventricular con evolución bacteriológica exitosa. Se discute las dosis utilizadas por vía endovenosa e intraventricular. Conclusiones: el uso de este antibiótico por vía intraventricular puede ser una alternativa exitosa en casos de gérmenes altamente resistentes y cuando no exista otra alternativa terapéutica.

Introduction: Tigecycline is a drug of restricted use in pediatrics. The use of this antibiotic intraventricularly is a decision of compassive use in cases of highly resistant bacteria, and in cases where there is no other alternative. Clinical case: We present six cases of patients with a diagnosis of ventriculitis caused by Enterococcus faecium, who received intraventricular tigecycline with successful microbiological evolution. The doses used intravenously and intraventricularly are discussed. Conclusions: the use of this antibiotic intraventricularly can be a successful alternative in cases of highly resistant germs, when there are not alternative options. Key words: ventriculitis, Enterococcus faecium, tigecycline, intraventricula

Perfil fenotípico de resistência à colistina e tigeciclina em um hospital público no Brasil / Phenotypical profile of colistin and tigecycline resistance in a public hospital in Brazil / Perfil fenotípico de resistencia a la colistina y tigeciclina en un hospital público de Brasil

Justificativa e objetivos: Infecções Relacionadas à Assistência à Saúde (IRAS) causadas por bacilos Gram negativos multirresistentes (BGN-MDR) são consideradas um problema de saúde pública e um impacto nas taxas de mortalidade nas Unidades de Terapia Intensiva (UTI). O objetivo deste estudo foi verificar o perfil fenotípico de resistência à colistina e à tigeciclina, consideradas como último recurso terapêutico aos BGN-MDR. Métodos: Os dados foram coletados nas fichas de busca ativa do serviço de controle de infecções e prontuários médicos de pacientes internados em duas UTIs de um hospital público de Joinville, entre janeiro de 2016 e junho de 2017. Resultados: Ocorreram 256 IRAS por BGN, acometendo principalmente o gênero masculino (62%), com mediana de idade de 65 anos. Entre os BGN, 37% expressaram MDR; sendo as espécies mais frequentes: Klebsiella pneumoniae e (47%), Acinetobacter baumannii (23%) e Stenotrophomonas maltophilia (11%). A resistência de BGN-MDR à colistina e tigeciclina foi de 5% e de 12%, respectivamente; 5% dos isolados foram resistentes aos dois antibióticos. A taxa de óbito entre os pacientes com IRAS por BGN-MDR resistentes à colistina foi mais alta (60%) que aquelas à tigeciclina (45%). Conclusão: K. pneumoniae e A. baumannii produtores de carbapenemases, resistentes a colistina e tigeciclina prevaleceram entre os BGN-MDR, e estiveram associadas a maioria dos óbitos. Essas observações, junto com o alto uso de carbapenêmicos na terapia empírica, mostra a necessidade do uso racional de antimicrobianos.(AU)

Background and objectives: Healthcare-associated Infections (HAIs) caused by multidrug-resistant Gram-negative bacilli (GNB-MDR) are considered a public health problem and have an impact on mortality rates in Intensive Care Units (ICU). The aim of this study was to verify the phenotypic profile of resistance to colistin and tigecycline, considered as the last antimicrobial choice to treat BGNMDR infections. Methods: Data were collected on the active search records of the infection control service and medical records of patients admitted to two ICUs at a public hospital in Joinville between January 2016 and June 2017. Results: There were 256 HAIs caused by GNB, mainly affecting males (62%), with a median age of 65 years. Among GNBs, 37% expressed MDR; the most frequent species were: Klebsiella pneumoniae (47%), Acinetobacter baumannii (23%) and Stenotrophomonas maltophilia (11%). The resistance of GNB-MDR to colistin and tigecycline was 5% and 12%, respectively; 5% of the isolates were resistant to both antibiotics. The death rate among patients with HAIs caused by colistin-resistant GNB-MDR was higher (60%) than those to tigecycline (45%). Conclusion: Carbapenemase-producing K. pneumoniae and A. baumannii, resistant to colistin and tigecycline, prevailed among GNB-MDRs, and were associated with most deaths. These observations, coupled with the high use of carbapenems in empirical therapy, show the need for rational use of antimicrobials.(AU)

Justificación y objetivos: Las Infección nosocomial (IHs) causadas por bacilos Gram negativos multirresistentes (BGN-MDR) se consideran un problema de salud pública y un impacto en las tasas de mortalidad en las Unidades de Terapia Intensiva (UTI). El objetivo de este estudio fue verificar el perfil fenotípico de resistencia a la colistina ya la tigeciclina, consideradas como último recurso terapéutico a los BGN-MDR. Métodos: Los datos fueron recolectados en las fichas de búsqueda activa del servicio de control de infecciones y prontuarios médicos de pacientes internados en dos UTIs de un hospital público de Joinville, entre enero de 2016 y junio de 2017. Resultados: Ocurrieron 256 IHs por BGN, que afectan principalmente al género masculino (62%), con mediana de edad de 65 años. Entre los BGN, el 37% expresó MDR; siendo las especies más frecuentes: Klebsiella pneumoniae (47%), Acinetobacter baumannii (23%) y Stenotrophomonas maltophilia (11%). La resistencia de BGN-MDR a la colistina y tigeciclina fue del 5% y del 12%, respectivamente; 5% de los aislados fueron resistentes a los dos antibióticos. La tasa de muerte entre los pacientes con IH causadas por los BGN-MDR resistentes la colistina fue más alta (60%) que aquellas a tigeciclina (45%). Conclusión: K. pneumoniae y A. baumannii productoras de carbapenemases, resistentes la colistina y la tigeciclina, fueron más frecuentes entre los BGN-MDR y su asociación estuvo presente en la mayoría de las muertes. Estas observaciones, junto con el alto uso de carbapenems en la terapia empírica, muestran la necesidad de un uso racional de los antimicrobianos.(AU)

Safety and Effectiveness of High Dose Tigecycline for Treating Patients with Acute Leukemia after Ineffctiveness of Carbapenems Chemotherapy Combinating with Febrile Neutropenia: Retrospective study / 中国实验血液学杂志

<p><b>OBJECTIVE</b>To investigate the safety and efficacy of high dose tigecycline for treatment of fibric neutrope-nia in acute leukemia patients after ineffectiveness of carbapenems chemotherapy of acute leukemia.</p><p><b>METHODS</b>The clinical data of 41 acute leukemia patients with febrile ncutropenia received high dose tigecycline (100 mg q12h), who showed ineffectiveness of treatment with carbapenems, from 20151.30-2017.1. 29 in our hospital were collected and analyzed retrospectively. The temperature, inflammatory indicators as well as hepatic and renal function before and after treatment with tigecycline were compared.</p><p><b>RESULTS</b>Among 41 patients treated with tigecycline due to ineffectiveness of treatment with carbapenems, the infection had been controled in 34 cases, 7 patients died due to ineffectiveness of anti-infective treatment, these patients all were patients with relapse/refractory leukemia. 41 patients were examined etialogically, as a result, 22 patients showed possitive, among them the gram-negative bacill was found in 11(11/22) cases. The average deferves counce time of tigecycline was 28.2±12.0 hours. The temperature of patients treated with tigecycline for 48 hours decreased significantly (P<0.05). There were no significant differences in calcitonin and C-reactive protein levels after treatment with tigecycline (P>0.05), but cacitonin level displayed decrease tread. There was no hepatic and renal impairment after treatment with tigecycline, but levels of as partate aminotransferase, total bilirubin and blood area nitrogen in blood significantly increased as compared with levels before treatment with tigecycline (P<0.05).</p><p><b>CONCLUSION</b>The application of high dose tigecycline for treatment of febrile neutropenia is safety and effective. The high dose tigecycline can decrease the temperature, calcitonin and C-reactive protein levels, and can control infection without the hepatic and renal impairment, but it needs to be confimed by more prospective studies.</p>

Tigeciclina en infecciones de piel y tejidos blandos complicadas / Tigecycline in complicated skin and soft-tissue infection

Objetivo: evaluar la mejor evidencia actual disponible para generar recomendaciones con respecto a la efectividad y seguridad del uso de tigeciclina en adultos con infección de piel y tejidos blandos (IPTB). Materiales y métodos: se realizó una revisión sistemática de la literatura, seleccionando los metaanálisis y experimentos clínicos controlados (ECCs), los cuales se valoraron utilizando la herramienta SIGN (Scottish Intercollegiate Guidelines Network.), con el fin de generar tablas de evidencia según GRADE de los estudios de tigeciclina en la indicación de IPTB, para posteriormente utilizar un proceso Delphi modificado para calificar las diferentes recomendaciones. Resultados: la revisión sistemática se incluyeron 9 metaanálisis que incluyeron 5 estudios clínicos aleatorizados con 1873 pacientes, y de ellos 952 asignados al brazo de tigeciclina, no mostró inferioridad frente a los comparadores en curación clínica (RR= 0.76 IC95% 0,57 - 1.03), curación microbiológica (RR= 0.92 IC95% 0,61 - 1.38), eventos adversos serios RR 1,41 (IC95%0,97 a 2,35), ni mortalidad RR 1,9 (IC95%0,84 a 4,3). La tigeciclina puede relacionarse con mayor frecuencia de eventos adversos leves de origen gastrointestinal. Conclusión: en pacientes adultos con IPTB, se considera que el uso de tigeciclina en monoterapia en pacientes no críticamente enfermos es equivalente en eficacia a otras opciones terapéuticas antimicrobianas. Se debe considerar especialmente como terapia de ajuste en pacientes con infecciones polimicrobianas.

Objective: To assess current best evidence available to generate recommendations regarding the effectiveness and safety of tigecycline use in adults with skin and soft-tissue infections (SSTIs). Materials and methods: A systematic review of the literature was conducted by selecting meta-analyzes and controlled clinical trials (CCTs), which were assessed using the SIGN tool (Scottish Intercollegiate Guidelines Network) in order to generate evidence tables according to GRADE of studies of tigecycline in the SSTIs indication, and then using a modified Delphi Method to score the different recommendations. Results: Nine meta-analyzes were included compounded by five randomized clinical trials with a sample size of 1873 patients, where 952 patients were assigned to tigecycline. The group of patients with tigecycline showed no inferiority to the comparator in clinical cure (RR = 0.76 95% CI 0.57 - 1.03), microbiologic cure (RR = 0.92 95% CI 0.61 - 1.38), serious adverse events RR 1, 41 (95% CI 0.97 to 2.35) or mortality RR 1.9 (95% CI 0.84 to 4.3). Tigecycline may be related to increased frequency of minor adverse events of gastrointestinal origin. Conclusion: In adult patients with SSTIs, it is considered that the use of tigecycline in monotherapy in non-critically ill patients is equivalent in effectiveness to other antimicrobial treatment options. It should be especially considered as an adjustment therapy in patients with polymicrobial infections.

Tigeciclina en infecciones intraabdominales complicadas / Tigecycline in complicated intra-abdominal infections

Objetivo: evaluar la mejor evidencia actual disponible para generar recomendaciones, con respecto a la efectividad y seguridad del uso de tigeciclina en adultos con infección intraabdominal complicada. Materiales y métodos: se realizó una revisión sistemática de la literatura, seleccionando los metaanálisis y experimentos clínicos controlados, los cuales se valora- ron utilizando la herramienta SIGN, con el fin de generar tablas de evidencia según GRADE de los estudios de tigeciclina en la indicación infección intraabdominal complicada, para posteriormente utilizar un proceso Delphi modificado para calificar las diferentes recomendaciones con el fin de generar un consenso. Resultados: se analizaron los resultados basados en la revisión sistemática de la literatura en la que se incluyeron 5 metaanálisis que cumplieron los criterios de selección comparando tigeciclina con otros tratamientos antibióticos en infección intraabdominal complicada; de los cuales, 2711 pacientes recibieron al menos una dosis del antibiótico (1382 tigeciclina y 1389 el comparador) y en los que no se observaron diferencias estadísticamente significativas en los desenlaces evaluados al comparar tigeciclina con otros antibióticos. Conclusión: en pacientes adultos con infección intraabdominal complicada, se considera que el uso de tigeciclina en monoterapia es equivalente en eficacia y seguridad a otras opciones terapéuticas antimicrobianas y no representa un exceso de mortalidad en comparación a otros antibióticos

Objective: To assess current best evidence available to generate recommendations regarding the effectiveness and safety of tigecycline use in adults with complicated intra-abdominal infection (cIAIs). Materials and methods: We conducted a systematic review of published meta-analysis that evaluated tigecycline compared to other antimicrobials and included the indication of cIAI. Quality of the evidence was evaluated by using the SIGN tool (Scottish Intercollegiate Guidelines Network) according to GRADE, and final recommendations were assessed by a modified Delphi Method in order to develop a consensus. Results: Five meta-analyzes met the selection criteria comparing tigecycline with other antibiotic treatments in complicated intra-abdominal infection. Five randomized clinical trials comprised in these meta-analysis included 2711 patients that received at least one dose of antibiotic (1382 tigecycline and 1389 the comparator regimen), We found no statistically significant differences in the evaluated outcomes by comparing tigecycline with other antibiotics, including clinical and microbiologic efficacy, safety and drug related mortality Conclusion: In adult patients with cIAIs, the use of tigecycline as monotherapy is equivalent in effectiveness to other antimicrobial therapeutic options and does not represent an increase in mortality compared to other antibiotics.

Antimicrobial susceptibility of Brazilian Clostridium difficile strains determined by agar dilution and disk diffusion

Abstract Clostridium difficile is a leading cause of diarrhea in hospitalized patients worldwide. While metronidazole and vancomycin are the most prescribed antibiotics for the treatment of this infection, teicoplanin, tigecycline and nitazoxanide are alternatives drugs. Knowledge on the antibiotic susceptibility profiles is a basic step to differentiate recurrence from treatment failure due to antimicrobial resistance. Because C. difficile antimicrobial susceptibility is largely unknown in Brazil, we aimed to determine the profile of C. difficile strains cultivated from stool samples of inpatients with diarrhea and a positive toxin A/B test using both agar dilution and disk diffusion methods. All 50 strains tested were sensitive to metronidazole according to CLSI and EUCAST breakpoints with an MIC90 value of 2 μg/mL. Nitazoxanide and tigecycline were highly active in vitro against these strains with an MIC90 value of 0.125 μg/mL for both antimicrobials. The MIC90 were 4 μg/mL and 2 μg/mL for vancomycin and teicoplanin, respectively. A resistance rate of 8% was observed for moxifloxacin. Disk diffusion can be used as an alternative to screen for moxifloxacin resistance, nitazoxanide, tigecycline and metronidazole susceptibility, but it cannot be used for testing glycopeptides. Our results suggest that C. difficile strains from São Paulo city, Brazil, are susceptible to metronidazole and have low MIC90 values for most of the current therapeutic options available in Brazil.

Outpatient parenteral antimicrobial therapy for orthopedic infections – a successful public healthcare experience in Brazil

Abstract Treatment of orthopedic infections usually requires prolonged antimicrobial therapy, ranging from 14 days up to 6 months. Nowadays, rising levels of antimicrobial resistance demands parenteral therapy for many patients. Outpatient parenteral antimicrobial therapy (OPAT) is a modality that allows treatment out of hospital in these situations. In Brazil, where a public universal healthcare system allows full coverage for all citizens, implantation and dissemination of OPAT programs would be beneficial for patients and for the system, because it would allow a better allocation of health resources. The Instituto de Ortopedia e Traumatologia do Hospital das Clínicas da Faculdade de Medicina da USP (IOT) started, in July 2013, a partnership with municipal health authorities in Sao Paulo, Brazil, in order to initiate an OPAT program in which patients discharged from that hospital would be able to continue antimicrobial therapy at primary care facilities. When necessary, patients could also receive their therapy at the day-hospital located at IOT. Primary care nursing and physician staff were trained about antimicrobial infusion and peripherally inserted central catheter manipulation. An OPAT specific antimicrobial protocol was designed and a special reference and counter-reference organized. As a result, 450 primary healthcare professionals were trained. In the first year of this program, 116 patients were discharged for OPAT. Chronic and acute osteomyelitis were most frequent diagnosis. Teicoplanin, ertapenem and tigecycline were the most used drugs. Duration of treatment varied from 10 to 180 days (average 101, median 42). Total sum of days in OPAT regimen was 11,698. Only 3 patients presented adverse effects. Partnership between services of different levels of complexity allowed implantation of a safe and effective public healthcare OPAT program for treatment of orthopedic infections. This program can serve as a model for developing similar strategies in other regions of Brazil and Latin America.

Over expression of AdeABC and AcrAB-TolC efflux systems confers tigecycline resistance in clinical isolates of Acinetobacter baumannii and Klebsiella pneumoniae

Abstract: INTRODUCTION: Due to the wide use of tigecycline in the treatment of severe infections caused by multidrug-resistant (MDR) bacteria, clinical resistance to tigecycline has increased in recent years. Here, we investigated the relationship between tigecycline resistance and the expression of efflux pumps. METHODS: Clinical isolates of Acinetobacter baumannii and Klebsiella pneumoniae were consecutively collected from hospitalized patients in three hospitals. The minimum inhibitory concentration (MIC) of tigecycline was determined using the broth microdilution method. Expression levels of efflux pump genes and regulators were examined by quantitative real-time reverse transcription polymerase chain reaction. The correlations between tigecycline MICs and gene expression levels were analyzed. RESULTS: Overall, 1,026 A. baumannii and 725 K. pneumoniae strains were collected. Most strains were isolated from sputum. The tigecycline resistance rate was 13.4% in A. baumannii isolates and 6.5% in K. pneumoniae isolates. Overexpression of AdeABC and AcrAB-TolC efflux systems was observed found in clinical tigecycline-resistant isolates. The tigecycline MIC had a linear relationship with the adeB expression level in A. baumannii isolates, but not with the acrB expression level in K. pneumoniae isolates. There were significant linear trends in the overexpression of ramA as the tigecycline MIC increased in K. pneumoniae isolates. CONCLUSIONS: Tigecycline resistance in A. baumannii and K. pneumoniae was strongly associated with the overexpression of efflux systems. More studies are needed to elucidate whether there are other regulators that affect the expression of adeB in A. baumannii and how ramA affects the expression of acrB in K. pneumoniae.

Combinations of chloroquine with tigecycline and telithromycin induce early onset of apoptosis in Plasmodium falciparum in vitro

OBJECTIVE: This study aimed to demonstrate that apoptosis in Plasmodium falciparum can be measured using kits originally designed for mammalian cells. The antimalarial chloroquine and antibiotics tigecycline and telithromycin were used to show the performance of the assays. METHODS: Nuclear stain DAPI fluorescence was used to estimate cytotoxicity. Apoptotic assays used were: CaspaTag™ for caspase activation, acridine orange for nuclear condensation, and TUNEL for DNA fragmentation. RESULTS: The IC50 values (95% confidence interval) for telithromycin (TL), tigecycline (TG) and chloroquine (CQ) were found to be 1.00 (0.47-1.53) µM, 4.56 (2.32-6.80) µM, and 0.019 (0.0089-0.029) µM, respectively. Activated caspase-like molecules seemed to be present in all erythrocytic stages, appearing to rise and fall with cell cycle progression with drug exposure appearing to dysregulate this pattern. Nuclear condensation and DNA fragmentation occurred late in the untreated erythrocytic life cycle of the parasite but were advanced by drug exposure. CONCLUSION: The study shows that drug-induced apoptosis can be measured in Plasmodium falciparum using the methods. These assays could be used for drug discovery, in particular, using high throughput flow cytometry.

An unexpected similarity between antibiotic-resistant NDM-1 and beta-lactamase II from Erythrobacter litoralis

NDM-1 (New Delhi metallo-beta-lactamase) gene encodes a metallo-beta-lactamase (MBL) with high carbapenemase activity, which makes the host bacterial strain easily dispatch the last-resort antibiotics known as carbapenems and cause global concern. Here we present the bioinformatics data showing an unexpected similarity between NDM-1 and beta-lactamase II from Erythrobacter litoralis, a marine microbial isolate. We have further expressed these two mature proteins in E. coli cells, both of which present as a monomer with a molecular mass of 25 kDa. Antimicrobial susceptibility assay reveals that they share similar substrate specificities and are sensitive to aztreonam and tigecycline. The conformational change accompanied with the zinc binding visualized by nuclear magnetic resonance, Zn(2+)-bound NDM-1, adopts at least some stable tertiary structure in contrast to the metal-free protein. Our work implies a close evolutionary relationship between antibiotic resistance genes in environmental reservoir and in the clinic, challenging the antimicrobial resistance monitoring.

Estudio de susceptibilidad a tigeciclina: Influencia del agar Mueller-Hinton en el método de difusión en agar y validación del método E-test® para Acinetobacter baumannii / In vitro evaluation of tygecicline: Influence of Mueller-Hinton agar in agar diffussion methods and validation of E-test® for Acinetobacter baumannii

Tigecycline is a glicylcicline with broad antimicrobial spectrum. Susceptibility testing to this drug for Acinetobacter is difficult in hospitals due to the utilization of the disk diffusion method. FDA break points have shown an unacceptable rate of errors (23 percent) for disk diffusion versus broth microdilution in American studies and overcall of resistance depending on the brand of Mueller Hinton agar used. Modifications to these FDA break points have been proposed, but there is not enough evidence yet. Data from a multicenter study from Chile allowed the evaluation of the characteristics of the agar used for susceptibility testing and the utility of E-test as an alternative MIC method for Acinetobacter. The Mueller Hinton agar brand is an important factor that affects disk diffusion method results. There is very good correlation between broth microdilution and E-test for the susceptibility category as well as for MIC determination. The intermedíate and resistant results obtained with disk diffusion method should be checked by using E-test.

Tigeciclina es una glicilciclina de amplio espectro antimicrobiano. La determinación de la susceptibilidad a este fármaco presenta dificultades en el laboratorio asistencial al utilizar la técnica de difusión por disco para Acinetobacter spp. Los puntos de corte -según la (FDA- han mostrado una tasa inaceptable de errores (23 por ciento) en comparación con el método de micro-dilución en caldo en estudios americanos, diversas evaluaciones demuestran que existe una sobreestimación de resistencia in vitro dependiendo de las características del agar Mueller Hinton utilizado. Se han propuesto modificaciones a los puntos de corte pero no se han oficializado por insuficientes evidencias. Los datos de un estudio multicéntrico realizado en Chile permitieron evaluar la influencia de las distintas marcas de medios de cultivo en el tamaño de los halos y la utilidad de la epsilometría (E-test®) como método CIM para Acinetobacter sp. La marca de agar Mueller Hinton y otros factores propios del medio dificultan la determinación de la susceptibilidad a tigeciclina utilizando difusión por disco. Existe muy buena correlación entre la micro-dilución en caldo y el E- test®, tanto para la categoría de susceptibilidad como para la CIM. Por esto, se sugiere que los resultados intermedios o resistentes obtenidos por difusión en agar para A. baumannii sean comprobados mediante el uso de E-test®.

La experiencia clínica con tigeciclina: Una breve revisión / Clinical experience with tygecicline: A brief review

The available clinical experience with tigecycline is analyzed under the perspective of a systematic review of the hterature, related to the already approved indications reported in the recent hterature. The safety profile is checked in the above mentioned clinical trials. The available information allows supporting tigecycline efficiency in the managing of complicated skin and soft tissues infections, complicated intrabdominales infections and in community acquired pneumonias.

Se analiza, bajo la perspectiva de una revisión sistemática de la literatura médica, la experiencia clínica con tigeciclina, en las indicaciones ya aprobadas por las entidades reguladoras reportadas en la literatura reciente. Se revisa el perfil de seguridad y tolerabilidad en dichos ensayos clínicos. La información disponible permite avalar su eficacia en el manejo de infecciones de piel y tejidos blandos complicadas, infecciones intra-abdominales complicadas y neumonías adquiridas en la comunidad.

Tigeciclina versus vancomycin más aztreonam en el tratamiento de infecciones complicadas de piel y tejidos blandos: Experiencia en Latinoamérica / Tigecycline as effective as vancomycin plus aztreonam in the treatment of complicated skin and skin structure infections: Experience in Latin America

BACKGROUND: Treating complicated skin and skin structure infections (cSSSIs) can be challenging. Tigecycline was compared to vancomycin/aztreonam in patients with cSSSIs in a multinational trial; this article reports on the Latin American (LA) population. METHODS: Patients were randomly assigned to receive tigecycline or vancomycin/ aztreonam. Primary endpoint was clinical cure rate at test-of-cure (TOC). Several secondary endpoints and safety were also assessed. RESULTS: A subtotal of 167 LA patients from the multinational trial (N = 573) received ≥ 1 dose of study drug. At TOC, cure rates were similar between tigecycline and vancomycin/aztreonam in the clinically evaluable population.) Noninferiority of tigecycline could not be demonstrated (insufficient sample sizes). Tigecycline-treated patients had higher incidences of nausea, vomiting, anorexia; vancomycin/aztreonam-treated patients had higher incidences of pruritus and rash. CONCLUSIONS: Efficacy results in the LA population were consistent with the multinational study suggesting that tigecycline is noninferior to vancomycin/aztreonam in treating patients with cSSSI.

INTRODUCCIÓN: El tratamiento de infecciones complicadas de piel y tejidos blandos (ICPTB) puede representar un desafío. Se comparó la eficacia de tigeciclina versus vancomicina/aztreonam en pacientes con ICPTB en un estudio multicéntrico; este artículo se refiere a la experiencia en Latinoamérica (LA). MÉTODO: Se asignaron, en forma randomizada, los pacientes a dos grupos de tratamiento: tigeciclina o vancomicina/aztreonam. La meta a evaluar (outcome) primaria fue la curación clínica, denominada test de curación (TC). Se establecieron, además, metas secundarias y la evaluación de seguridad del fármaco. RESULTADOS: Un subtotal de 167 pacientes procedentes de LA, de un estudio multinacional que incluyó 573 pacientes, recibieron ≥ 1 dosis del fármaco en estudio. Al TC, los porcentajes de curación fueron similares entre tigeciclina y vanco-micina/aztreonam en los pacientes clínicamente evaluables). La no inferioridad de tigeciclina no pudo ser demostrada (tamaño de muestra insuficiente). Los pacientes tratados con tigeciclina tuvieron mayor incidencia de náuseas, vómitos y anorexia; los pacientes que recibieron vancomicina/aztreonam tuvieron mayor incidencia de prurito y rash. CONCLUSIONES: Los resultados de eficacia en LA fueron consistentes con el estudio multinacional sugiriendo que tigeciclina no es inferior a vancomicina/aztreonam en el tratamiento de pacientes con ICPTB.