RESUMEN
Corynebacterium striatum is a rare, but likely underreported, cause of serious infections in immunocompromised hosts and generally is susceptible to multiple classes of antimicrobial agents. Here we report the first case of C. striatum infection in a solid organ transplant recipient. Three years after heart transplantation, a 58-year-old man developed bilateral pneumonia and pulmonary embolism. He did not improve with levofloxacin, piperacillin/tazobactam, and heparin treatment. A homogeneous population of abundant gram-positive rods was repeatedly demonstrated in sputum and bronchoalveolar lavage fluid, and C. striatum was grown in pure culture. The isolate was unusual for its multidrug-resistant (MDR) antimicrobial susceptibility pattern. The pneumonia resolved with 4 weeks of vancomycin therapy, in combination with rifampin given only during the first 2 weeks of treatment. The isolation of coryneforms ("diphtheroids") is often attributed to contamination. Their abundant presence on direct examination of specimens and/or their growth in pure culture suggest a pathogenic role, however, and indicate the need for accurate microbiological identification, particularly in immunocompromised hosts who have been hospitalized and previously treated with antibiotics. Combination therapy that includes vancomycin may be the most prudent treatment for MDR C. striatum infections.
Asunto(s)
Infecciones por Corynebacterium/etiología , Farmacorresistencia Bacteriana Múltiple , Trasplante de Corazón/efectos adversos , Neumonía Bacteriana/etiología , Anfotericina B/uso terapéutico , Ciprofloxacina/uso terapéutico , Corynebacterium/clasificación , Corynebacterium/aislamiento & purificación , Infecciones por Corynebacterium/diagnóstico , Infecciones por Corynebacterium/tratamiento farmacológico , Quimioterapia Combinada/uso terapéutico , Corazón/microbiología , Humanos , Masculino , Neumonía Bacteriana/diagnóstico , Neumonía Bacteriana/diagnóstico por imagen , Neumonía Bacteriana/tratamiento farmacológico , RadiografíaAsunto(s)
Insuficiencia Cardíaca/cirugía , Corazón Auxiliar , Procedimientos Quirúrgicos Mínimamente Invasivos/instrumentación , Implantación de Prótesis/instrumentación , Adulto , Australia/epidemiología , Ensayos Clínicos como Asunto , Seguridad de Equipos , Humanos , Masculino , Resultado del Tratamiento , Estados Unidos/epidemiologíaRESUMEN
A maze design is discussed for a Therac 20 linear accelerator (manufactured by Atomic Energy of Canada, Ltd.) which reduces the flux of neutrons at the door to permissible levels in controlled areas. The L-shaped design allows for a relatively light door at the end of the maze, consisting of 5.08-cm (2-in.) borated polyethylene and 2-mm lead. A comparison is made between the neutron dose equivalent (DE) calculated by various methods and the DE measured with a variety of portable neutron survey meters. In addition, the neutron energy spectrum outside the maze at 1 m from the door, measured with a polyethylene multisphere LiI system, is reported.