Factores de riesgo asociados con bacteriemia nosocomial en recién nacidos de bajo peso al nacimiento. Hospital Grady Memorial, Atlanta

ResumenIntroducciónLa bacteriemia nosocomial es una causa frecuente de infección nosocomial en los recién nacidos admitidos en las unidades de cuidados intensivos neonatales y está asociada con factores de riesgo, reconocidos y no reconocidos, de infección nosocomial. Aún existen pocas evidencias sobre los factores de riesgo de bacteriemia nosocomial en recién nacidos de bajo peso al nacimiento.ObjetivosInvestigar factores de riesgo de bacteriemia nosocomial en neonatos con un peso inferior a 1.500 g ingresados en la unidad de cuidados intensivos neonatal.MétodosSe realizó un estudio prospectivo en recién nacidos de bajo peso al nacimiento (≤ 1.500 g) durante 22 meses. Para determinar la asociación estadística entre la bacteriemia nosocomial y los factores de riesgo perinatales y nosocomiales, se llevó a cabo un análisis bivariante de regresión logística (método de regresión por pasos).ResultadosSe estudió a un total de 72 pacientes con bacteriemia nosocomial y 174 sin ella. La permanencia del catéter umbilical un tiempo mayor o igual a 7 días y la permanencia del catéter periférico arterial durante un día o más resultaron ser los factores independientemente asociados con bacteriemia nosocomial.ConclusiónEl mantenimiento del catéter umbilical más de 7 días, la permanencia del catéter periférico arterial más de 1 día y el peso al nacimiento inferior a 1.500 g fueron factores determinantes de bacteriemia nosocomial. Por la importancia de estas técnicas invasivas como fuente de bacteriemia nosocomial, es preciso revisar su tiempo de permanencia con el objetivo de disminuir la incidencia de bacteriemia nosocomial.AbstractBackgroundNosocomial bloodstream infections occur frequently in Neonatal Intensive Care Units and are associated with recognized and unrecognized risk factors. Little has been published regarding risk factors for bloodstream infections in low birth weight neonates.ObjectiveTo investigate risk factors for bloodstream infection in neonates < 1,500 g admitted at a Neonatal Intensive Care Unit.MethodsA prospective study was undertaken in low birth weight neonates (< 1,500g) during a 22 months period. Bivariant, and logistic regresion (stepwise procedure) analysis was used to determine the significance association of bloodstream infection and perinatal and nosocomial risk factors.ResultsA total of 72 patiens with nosocomial bacteriemia and 147 non bacteriemic patients were studied. Independent risk factors associated with bloodstream infection were birth weight, persistence of umbilical catheter > 7 days and persistence of peripheral arterial catheter > 1 day.ConclusionsThe uses of umbilical catheter > 7 days, peripheral arterial catheter > 1 day and birth weight < 1,500 g were significant determinants of nosocomial bloodstream infection risk. Because of the importance of invasive procedures as a source of nosocomial bloodstream infections, the lines duration needs to be reviewed with the aim of reducing the incidence of blood stream infection

Population genomics of the critically endangered kākāpō

Summary The kākāpō is a flightless parrot endemic to New Zealand. Once common in the archipelago, only 201 individuals remain today, most of them descending from an isolated island population. We report the first genome-wide analyses of the species, including a high-quality genome assembly for kākāpō, one of the first chromosome-level reference genomes sequenced by the Vertebrate Genomes Project (VGP). We also sequenced and analyzed 35 modern genomes from the sole surviving island population and 14 genomes from the extinct mainland population. While theory suggests that such a small population is likely to have accumulated deleterious mutations through genetic drift, our analyses on the impact of the long-term small population size in kākāpō indicate that present-day island kākāpō have a reduced number of harmful mutations compared to mainland individuals. We hypothesize that this reduced mutational load is due to the island population having been subjected to a combination of genetic drift and purging of deleterious mutations, through increased inbreeding and purifying selection, since its isolation from the mainland ∼10,000 years ago. Our results provide evidence that small populations can survive even when isolated for hundreds of generations. This work provides key insights into kākāpō breeding and recovery and more generally into the application of genetic tools in conservation efforts for endangered species