RESUMEN
We report the case of a twenty-year-old immunocompetent male patient presenting to the emergency room with pharyngitis and fever. Blood cultures were drawn and Arcanobacterium haemolyticum (rough biotype) was recovered. The presence of the arcanolysin gene was investigated at the molecular level and the upstream region was amplified and sequenced in order to correlate it with the smooth or rough biotype. Although the isolate was susceptible to penicillin, vancomycin and gentamicin, empirical treatments first with amoxicillin/clavulanic acid (1g/12h) and then with ceftriaxone (1g/12h) failed and the infection evolved to sepsis. Finally, treatment with vancomycin (1g/12h) plus piperacillin/tazobactam (4.5g/8h) was effective. Lemierre's syndrome was ruled out. To the best of our knowledge, this is the first case of bacteremia by A. haemolyticum reported in Argentina.
Asunto(s)
Infecciones por Actinomycetales , Arcanobacterium , Bacteriemia , Sepsis , Infecciones por Actinomycetales/diagnóstico , Infecciones por Actinomycetales/tratamiento farmacológico , Adulto , Bacteriemia/tratamiento farmacológico , Humanos , Masculino , Adulto JovenRESUMEN
Carbapenemase resistance in Enterobacterales is a global public health problem and rapid and effective methods for detecting these resistance mechanisms are needed urgently. Our aim was to evaluate the performance of a MALDI-TOF MS-based "Klebsiella pneumoniae carbapenemase" (KPC) detection protocol from patients' positive blood cultures, short-term cultures, and colonies in healthcare settings. Bacterial identification and KPC detection were achieved after protein extraction with organic solvents and target spot loading with suitable organic matrices. The confirmation of KPC production was performed using susceptibility tests and blaKPC amplification using PCR and sequencing. The KPC direct detection (KPC peak at approximately 28.681 Da) from patients' positive blood cultures, short-term cultures, and colonies, once bacterial identification was achieved, showed an overall sensibility and specificity of 100% (CI95: [95%, 100%] and CI95: [99%, 100%], respectively). The concordance between hospital routine bacterial identification protocol and identification using this new methodology from the same extract used for KPC detection was ≥92%. This study represents the pioneering effort to directly detect KPC using MALDI-TOF MS technology, conducted on patient-derived samples obtained from hospitals for validation purposes, in a multi-resistance global context that requires concrete actions to preserve the available therapeutic options and reduce the spread of antibiotic resistance markers.
RESUMEN
New Delhi metallo-ß-lactamase (NDM)-producing isolates are usually resistant to most ß-lactams and other antibiotics as a result of the coexistence of several resistance markers, and they cause a variety of infections associated to high mortality rates. Although NDM-1 is the most prevalent one, other variants are increasing their frequency worldwide. In this study we describe the first clinical isolate of NDM-5- and RmtB-producing Escherichia coli in Latin America. E. coli (Ec265) was recovered from a urine sample of a female outpatient. Phenotypical and genotypical characterization of resistance markers and conjugation assays were performed. Genetic analysis of Ec265 was achieved by whole genome sequencing. Ec265 belonging to ST9693 (CC354), displayed resistance to most ß-lactams (including carbapenems), aminoglycosides (gentamicin and amikacin), and quinolones. Several resistance genes were found, including blaNDM-5 and rmtB, located on a conjugative plasmid. blaNDM-5 genetic context is similar to others found around the world. Co-transfer of multiple antimicrobial resistance genes represents a particular challenge for treatment in clinical settings, whereas the spread of pathogens resistant to last resort antibiotics should raise an alarm in the healthcare system worldwide.
Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Escherichia coli/genética , Proteínas de Escherichia coli/genética , Femenino , Humanos , América Latina , Metiltransferasas/genética , Pruebas de Sensibilidad Microbiana , Plásmidos , beta-Lactamasas/genéticaRESUMEN
In this study, we identified specific carbapenemase-producing isolates applying an easy and rapid protocol for the detection of mature KPC-2 ß-lactamase by MALDI-TOF MS from colony and positive blood culture bottles. In addition, we evaluated the correlation of the ~11,109â¯Da signal as a biomarker associated with KPC-2 production. A collection of 126 well-characterized clinical isolates were evaluated (including 60 KPC-2-producing strains). Presence of KPC-2 was assessed by MALDI-TOF MS on protein extracts. Samples were prepared using the double layer sinapinic acid technique. In order to identify mature KPC-2, raw spectra were analyzed focusing on the range between m/z 25,000-30,000â¯Da. A single distinctive peak, at approximately m/z 28,544â¯Da was found in all clinical and control KPC-2-producing strains, and consistently absent in the control groups (ESBL producers and susceptible strains). This peak was detected in all species independently of where the gene blaKPC-2 was embedded. Statistical results showed 100% sensitivity, CI95%: [94.0%; 100%] and 100% specificity, CI95%: [94.6%; 100%], indicating a promising test with a high discriminative power. KPC-2 ß-lactamase could be directly detected from both colonies and blood culture bottles. On the other hand, the m/z 11,109â¯Da signal determinant was only associated with 32% of Klebsiella pneumoniae and Escherichia coli KPC positive isolates. This MALDI-TOF MS methodology has the potential to detect directly the widespread and clinically relevant carbapenemase, KPC-2, in Enterobacterales with a straightforward, low cost process, assuming MALDI-TOF MS is already adopted as the main identification tool, with clear clinical implications on antibiotic stewardship for early infection treatment.
Asunto(s)
Proteínas Bacterianas/metabolismo , Técnicas de Tipificación Bacteriana/métodos , Escherichia coli/aislamiento & purificación , Klebsiella pneumoniae/aislamiento & purificación , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/métodos , beta-Lactamasas/metabolismo , Escherichia coli/química , Escherichia coli/enzimología , Infecciones por Escherichia coli/microbiología , Humanos , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/química , Klebsiella pneumoniae/enzimologíaRESUMEN
A partir del recorte longitudinal del caso clínico de un niño, se analiza el despliegue de la función materna y paterna en el devenir de su constitución psíquica, las implicancias en su desarrollo y cómo va evolucionando a partir de un cambio en el posicionamiento de ambos padres. Las manifestaciones del juego del niño, la expresión de su lenguaje, y la organización del yo desde un enfoque metapsicológico, son las fuentes para analizar el desarrollo psíquico. A su vez, se contempla el impacto de la llegada del diagnóstico de TEA, enlazado al de discapacidad, y las implicancias aparejadas AU
À partir de la coupe longitudinale d'un cas clinique d'un enfant, le déploiement de la fonction maternelle et paternelle dans le développement de leur constitution psychique est analysé, les implications sur son développement et comment il évolue à partir d'un changement de positionnement des deux parents. Les manifestations du jeu de l'enfant, l'expression de leur langage, et l'organisation de soi à partir d'une approche métapsychologique, sont les sources pour analyser le développement psychique. Parallèlement, l'impact de l'arrivée du diagnostic de autisme est envisagé, liés au invalidité, et aux implications qui y sont associées AU
From the longitudinal section of the clinical case of a child, the deployment of the maternal and paternal function in the development of their psychic constitution is analyzed, including the implications for its development and how it evolves from a change in the positioning of both parents. The manifestations of the child's play, the expression of his language, and the organization of the self from a metapsychological approach, are the sources to analyze psychic development. At the same time, the impact of the arrival of the diagnosis of autism, linked to that of disability, and the associated implications are considered AU
Resumo Do corte longitudinal de um caso clínico de uma criança, analisa-se o desdobramento da função materna e paterna no desenvolvimento de sua constituição psíquica, as implicações para o seu desenvolvimento e como ele evolui a partir de uma mudança no posicionamento de ambos os pais. As manifestações da brincadeira infantil, a expressão da sua língua, e a organização do eu a partir de uma abordagem metapsicológica, eles são as fontes para analisar o desenvolvimento psíquico. Ao mesmo tempo, contempla-se o impacto da chegada do diagnóstico de autismo, ligada à deficiência, e as implicações decorrentes AU
Asunto(s)
Humanos , Masculino , Niño , Teoría Psicoanalítica , Relaciones Padre-Hijo , Trastorno del Espectro Autista/psicología , Relaciones Madre-Hijo/psicología , Ludoterapia , Lenguaje Infantil , Crianza del Niño/psicología , EgoRESUMEN
Abstract We report the case of a twenty-year-old immunocompetent male patient presenting to the emergency room with pharyngitis and fever. Blood cultures were drawn and Arcanobacterium haemolyticum (rough biotype) was recovered. The presence of the arcanolysin gene was investigated at the molecular level and the upstream region was amplified and sequenced in order to correlate it with the smooth or rough biotype. Although the isolate was susceptible to penicillin, vancomycin and gentamicin, empirical treatments first with amoxicillin/clavulanic acid (1g/12h) and then with ceftriaxone (1g/12h) failed and the infection evolved to sepsis. Finally, treatment with vancomycin (1 g/12 h) plus piperacillin/tazobactam (4.5g/8h) was effective. Lemierre's syndrome was ruled out. To the best of our knowledge, this is the first case of bacteremia by A. haemolyticum reported in Argentina.
Resumen Se describe el caso de un paciente varón inmunocompetente de veinte anos de edad que se presentó en la sala de emergencias con faringitis y fiebre. Se extrajeron muestras para realizar hemocultivos y se recuperó Arcanobacterium haemolyticum (biotipo rugoso). Se investigó la presencia del gen de la arcanolisina por un método molecular, y se amplificó y Faringitis; secuenció la región upstream de dicho gen para determinar su correlación con los biotipos lisos Bacteriemia; o rugosos. Aunque el aislamiento fue sensible a la penicilina, la vancomicina y la gentamicina, Sepsis; los tratamientos empíricos primero con amoxicilina/ácido clavulánico (1 g/12 h) y luego con Síndrome de Lemierre ceftriaxona (1 g/12 h) no fueron efectivos, y la infección evolucionó a sepsis. Finalmente, el tratamiento con vancomicina (1 g/12 h) más piperacilina/tazobactam (4,5g/8h) fue efectivo. Se descartó la presencia del síndrome de Lemierre. Según nuestro conocimiento, este es el primer caso de bacteriemia por A. haemolyticum reportado en Argentina.