RESUMEN
Widespread antibiotic use in clinical medicine and the livestock industry has contributed to the global spread of multidrug-resistant (MDR) bacterial pathogens, including Acinetobacter baumannii We report on a method used to produce a personalized bacteriophage-based therapeutic treatment for a 68-year-old diabetic patient with necrotizing pancreatitis complicated by an MDR A. baumannii infection. Despite multiple antibiotic courses and efforts at percutaneous drainage of a pancreatic pseudocyst, the patient deteriorated over a 4-month period. In the absence of effective antibiotics, two laboratories identified nine different bacteriophages with lytic activity for an A. baumannii isolate from the patient. Administration of these bacteriophages intravenously and percutaneously into the abscess cavities was associated with reversal of the patient's downward clinical trajectory, clearance of the A. baumannii infection, and a return to health. The outcome of this case suggests that the methods described here for the production of bacteriophage therapeutics could be applied to similar cases and that more concerted efforts to investigate the use of therapeutic bacteriophages for MDR bacterial infections are warranted.
Asunto(s)
Infecciones por Acinetobacter/terapia , Acinetobacter baumannii/efectos de los fármacos , Antibacterianos/uso terapéutico , Bacteriófagos/clasificación , Seudoquiste Pancreático/terapia , Pancreatitis Aguda Necrotizante/terapia , Terapia de Fagos/métodos , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/aislamiento & purificación , Acinetobacter baumannii/virología , Anciano , Farmacorresistencia Bacteriana Múltiple , Cálculos Biliares/patología , Humanos , Masculino , Minociclina/uso terapéutico , Seudoquiste Pancreático/microbiología , Pancreatitis Aguda Necrotizante/microbiologíaRESUMEN
We report a new preparative method for providing contrast through reduction in electron density that is uniquely suited for propagation-based differential x-ray phase contrast imaging. The method, which results in an air or fluid filled vasculature, makes possible visualization of the smallest microvessels, roughly down to 15 microm, in an excised murine liver, while preserving the tissue for subsequent histological workup. We show the utility of spatial frequency filtering for increasing the visibility of minute features characteristic of phase contrast imaging, and the capability of tomographic reconstruction to reveal microvessel structure and three-dimensional visualization of the sample. The effect of water evaporation from livers during x-ray imaging on the visibility of blood vessels is delineated. The deformed vascular tree in a cancerous murine liver is imaged.
Asunto(s)
Angiografía/métodos , Medios de Contraste , Microvasos/diagnóstico por imagen , Aire , Animales , Femenino , Formaldehído , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional/métodos , Hígado/anatomía & histología , Hígado/irrigación sanguínea , Hígado/patología , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/patología , Ratones , Ratones Endogámicos BALB C , Microvasos/anatomía & histología , Microvasos/patología , Tomografía Computarizada por Rayos X/métodosRESUMEN
We report the use of ultrasonic radiation pressure with phase contrast x-ray imaging to give an image proportional to the space derivative of a conventional phase contrast image in the direction of propagation of an ultrasonic beam. Intense ultrasound is used to exert forces on objects within a body giving displacements of the order of tens to hundreds of microns. Subtraction of images made with and without the ultrasound field gives an image that removes low spatial frequency features and highlights high frequency features. The method acts as an acoustic 'contrast agent' for phase contrast x-ray imaging, which in soft tissue acts to highlight small density changes.