The minimal inhibitory concentration for sulbactam was not associated with the outcome of infections caused by carbapenem-resistant Acinetobacter sp. treated with ampicillin/sulbactam

OBJECTIVE: The objective of this study was to evaluate whether the outcomes of carbapenem-resistant Acinetobacter infections treated with ampicillin/sulbactam were associated with the in vitro susceptibility profiles. METHODS: Twenty-two infections were treated with ampicillin/sulbactam. The median treatment duration was 14 days (range: 3-19 days), and the median daily dose was 9 g (range: 1.5-12 g). The median time between Acinetobacter isolation and treatment was 4 days (range: 0-11 days). RESULTS: The sulbactam minimal inhibitory concentration (MIC) ranged from 2.0 to 32.0 mg/L, and the MIC was not associated with patient outcome, as 4 of 5 (80%) patients with a resistant infection (MIC≥16), 5 of 10 (50%) patients with intermediate isolates (MIC of 8) and only 1 of 7 (14%) patients with susceptible isolates (MIC ≤4) survived hospitalization. CONCLUSION: These findings highlight the need to improve the correlation between in vitro susceptibility tests and clinical outcome. .

Factors influencing survival in patients with multidrug-resistant Acinetobacter baumannii infection

Multidrug-resistant (MDR) Acinetobacter baumannii (Acb) is a rapidly emerging pathogen in healthcare settings. The aim of this study was to evaluate the predictors of poor outcome in patients with MDR Acb. This is the first report documenting factors influencing survival in patients with MDR Acb in this tertiary hospital. This study is a prospective of the hospital epidemiology database. A total of 73 patients with 84 Acb isolates were obtained between August 2009 and October 2010 in this hospital. In the present study, the 30-day mortality rate was 39.7%. Of 84 Acb isolates, 50 (59%) were MDR, nine (11%) were pan-resistant, and 25 (30%) were non-MDR. The non-MDR isolates were used as the control group. The factors significantly associated with multidrug resistance included previous surgeries, presence of comorbidity (renal disease), use of more than two devices, parenteral nutrition, and inappropriate antimicrobial therapy. Significant predictors of 30-day mortality in the univariate analysis included pneumonia, diabetes mellitus, renal disease, use of more than two devices, and inappropriate antimicrobial therapy administered within two days of the onset of infection. The factors associated with mortality in patients with MDR Acb infection in this study were: age > 60 years, pneumonia, diabetes mellitus, renal disease, use of more than two invasive procedures, and inappropriate antimicrobial therapy. Vigilance is needed to prevent outbreaks of this opportunistic and deadly pathogen.

Mortalidad por Acinetobacter baumannii en unidades de cuidados intensivos en Colombia / Acinetobacter baumannii - related mortality in intensive care units in Colombia

OBJETIVO: Comparar la mortalidad en pacientes infectados por Acinetobacter baumannii multisensibles con pacientes infectados por A. baumannii multirresistentes hospitalizados en unidades de cuidados intensivos (UCI) de Colombia. MÉTODOS: Estudio prospectivo, observacional y multicéntrico. Se incluyó a 165 pacientes ingresados en las UCIs participantes entre abril de 2006 y abril de 2010. Se comparó la mortalidad de los pacientes con aislamientos clínicos de A. baumannii multirresistentes frente a aquellos multisensibles al día 14 y 30 de hospitalización. RESULTADOS: De los 165 pacientes adultos que presentaron infecciones asociadas al cuidado en salud (IACS) por A. baumannii, en 62 se encontraron bacterias multisensibles y en 103, multirresistentes. No se hallaron diferencias estadísticamente significativas en la mortalidad al día 14 de hospitalización en UCI. Sí se observaron en cambio diferencias significativas (P < 0,05) para mortalidad al día 30 de hospitalización entre los pacientes con aislamientos multirresistentes y multisensibles, y esta diferencia se mantuvo al controlar los factores de riesgo de los pacientes con análisis multivariado. CONCLUSIONES: La presencia de multirresistencia es el principal factor de riesgo para la mortalidad entre los pacientes con IACS por A. baumannii en las UCI de Colombia.

OBJECTIVE: Compare mortality in multidrug-susceptible Acinetobacter baumannii infected patients and multidrug-resistant A. baumannii-infected patients hospitalized in intensive care units (ICUs) in Colombia. METHODS: A prospective, observational, and multicenter study. A total of 165 patients admitted to the participating ICUs from April 2006 to April 2010 were included. On day 14 and day 30 of hospitalization, mortality in multidrug-resistant patients with clinical isolates of A. baumannii was compared with that in multidrug-susceptible patients. RESULTS: Of the 165 adult patients who had health care-associated infections (HAI) caused by A. baumannii, multidrug-susceptible bacteria were found in 62 patients and multidrug-resistant bacteria in 103. Statistically significant differences in mortality on day 14 of hospitalization in the ICU were not found. On the other hand, significant differences (P < 0.05) in mortality on day 30 of hospitalization were observed between patients with multidrug-resistant isolates and those with multidrug-susceptible isolates. This difference was maintained when the patients' risk factors were evaluated by multivariate analysis. CONCLUSIONS: The presence of multidrug resistance is the primary risk factor for mortality in patients with HAI caused by A. baumannii in Colombian ICUs.

Mortality rate in patients with nosocomial Acinetobacter meningitis from a Brazilian hospital

BACKGROUND: The mortality rate due to Acinetobacter baumannii nosocomial meningitis (ANM) is high. OBJECTIVE: The aim of this study was to evaluate the factors that have influence over the outcomes in ANM patients. METHODS: A retrospective analysis of 22 cases of ANM was conducted in a hospital with high incidence of multidrug resistance. RESULTS: The mean age of patients was 43 years (21 to 91) and 54.5 percent were male. All ANM cases occurred within 60 days of admission and the mean duration of illness was of 18.2 days. All cases were associated with previous neurosurgical procedures: elective surgery (27.2 percent), external shunt (54.4 percent) and emergency surgery due to trauma (18.1 percent). Imipenem resistance was observed in 40.9 percent of cases, but ampicillin/sulbactam resistance was lower (27.2 percent). The mortality rate of ANM patients was of 72.7 percent. The only risk factor associated with mortality was inappropriate therapy within five days after CSF collection. All patients who survived the meningitis episode had received appropriate therapy, in contrast to only 69.2 percent of those who did not survive (OR = 5.15; IC = 0.45-54.01). CONCLUSIONS: The high mortality rate observed in our study suggests the need for aggressive empirical treatment with addition of drugs, including intrathecal therapy, where multi-resistant A. baumannii is endemic.

Nosocomial infections due to Acinetobacter baumannii in a neurosurgery ICU.

Invasive infections caused by Acinetobacter baumannii in a post-operative neurosurgery ICU were studied. Sixty one patients admitted during a span of 11 months were culture positive for acinetobacter species from blood and/or CSF samples. They were followed up prospectively for evidence of infection and clinical outcome. 40 cases had clinical evidence of infection due to acinetobacter species while in 21 patients, the isolation of the organism was considered a contaminant. Acinetobacter baumannii was the most common organism associated with invasive infections. Respiratory tract was found to be the most common primary source of infection in patients with bacteraemia or meningitis. The age, sex and pre-operative hospital stay were not significantly different in the two groups (p>0.05), while post-operative hospital stay and mortality was significantly higher in patients with invasive infection (p<0.05). Acinetobacter baumannii was isolated from multiple sites (p<0.05) and repeatedly from the same site (p<0.001) in a significantly higher number of patients with invasive infections. Mortality was high in the patients infected with Acinetobacter baumannii. Even amongst the infected group, the patient shaving meningitis showed a higher mortality as compared to the patients having bacteraemia.