Epidemiology of bacterial infections in patients with liver cirrhosis. Experience in a Spanish tertiary health center.

INTRODUCTION: Bacterial infections represent a serious complication of liver cirrhosis. Traditionally, Gram negative bacteria have been described as the microorganisms responsible for the majority of the infections. However, in the past few years, changes in the microbiological spectrum have been described, and multiresistant bacteria are observed more frequently.  OBJECTIVE: To assess the proportion of patients with infections caused by multiresistant bacteria admitted to our hospital, and to obtain information about their epidemiology, risk factors and clinical impact.  MATERIALS AND METHODS: We performed a retrospective evaluation of 294 cirrhotic patients admitted to our unit due to infection between June, 2011, and June, 2013.  RESULTS: We isolated 310 microorganisms from 294 patients; 109 (35.2%) were Gram positive, 167 (53.9%), Gram negative, and 34, fungi (11%). As for the microbiological agents, the most frequent was Escherichia coli (98 isolations). The infection was community-acquired in 22.9% of cases, healthcareassociated in 38.1% and nosocomial in 39%. Worse liver infections and septic shock were more frequent among patients with multiresistant isolates (p=0.05); and intrahospital mortality was also higher among them (p=0.017). Previous hospital admission, antibiotic treatment 60 days before, nosocomial or healthcare-associated acquisition and bacterial isolation in control cultures were identified as possible risk factors for the development of multiresistant infection.  DISCUSSION: The results of our study confirm that important changes have ocurred in the microbiological spectrum of bacterial infections in patients with liver cirrhosis. Multiresistant bacteria are associated with high morbidity and mortality, as well as failure of traditional antibiotic treatment. Successfull control of the infection requires an early identification of patients at risk.

Evaluation of MycAssay™ Aspergillus for diagnosis of invasive pulmonary aspergillosis in patients without hematological cancer.

Methods based on real-time polymerase chain reaction (PCR) can speed up the diagnosis of invasive aspergillosis but are limited by a lack of standardization. We evaluated the commercially available MycAssay™ Aspergillus test for the diagnosis of invasive aspergillosis in patients without hematological cancer. We prospectively collected 322 lower respiratory tract samples (November 2009-January 2011) from 175 patients with lower respiratory tract infection and the following predisposing conditions: solid cancer (16.8%), cirrhosis (16.8%), corticosteroid therapy (71.7%), HIV infection (15.6%), chronic obstructive pulmonary disease (COPD, 52.6%), solid organ transplantation (kidney [1.2%], heart [3%], liver [4.6%]), or none (3.5%). Specimens were obtained when clinically indicated and analyzed in the microbiology laboratory. Aspergillus DNA was extracted and amplified by means of MycXtra® and MycAssay™ Aspergillus. Aspergillus spp. was isolated from 65 samples (31 patients). According to the European Organization for Research and Treatment of Cancer and Bulpa's criteria (for patients with COPD), 15 had probable invasive aspergillosis. MycAssay™ Aspergillus results were negative (n = 254), positive (n = 54), or indeterminate (n = 14). The sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic odds ratio of the MycAssay™ (first sample/any sample) were 86.7/93, 87.6/82.4, 34.1/34.1, 92.2/100, and 48/68.75. The differences between the proportion of samples with positive PCR determinations (63%) and the proportion of samples with Aspergillus spp. isolation (75%) did not reach statistical significance (P = 0.112). The median time from sample culture to visualization of fungal growth was 3 days, compared with ∼4 hours for MycAssay™ Aspergillus PCR. MycAssay™ Aspergillus showed high sensitivity for the diagnosis of invasive aspergillosis in patients without hematological cancer. Sensitivity increased when multiple samples were used. Compared with fungal culture, PCR significantly reduced the time to diagnosis.

Epidemiología de las infecciones bacterianas en pacientes con cirrosis hepática, experiencia de un centro español de atención terciaria / Epidemiology of bacterial infections in patients with liver cirrhosis. Experience in a Spanish tertiary health center

Introducción. Las infecciones bacterianas representan una complicación grave de la cirrosis. En los últimos años se han observado cambios en el espectro microbiológico de estas infecciones, fundamentalmente, el aumento de infecciones por gérmenes multirresistentes. Objetivo. Establecer la proporción de infecciones por microorganismos multirresistentes en pacientes cirróticos ingresados en un centro de atención de Madrid, y analizar su epidemiología, factores de riesgo e impacto clínico. Materiales y métodos. Se hizo un estudio retrospectivo en el cual se evaluaron 294 pacientes hospitalizados por infección bacteriana en el Hospital General Universitario Gregorio Marañón de Madrid, entre junio de 2011 y junio de 2013. Resultados. Se aislaron 310 microorganismos de 223 pacientes; 109 (35,2 %) eran Gram positivos, 167 (53,9 %), Gram negativos, y 34 (11 %), hongos. El agente etiológico más frecuente fue Escherichia coli (98 aislamientos). Las infecciones se habían adquirido en la comunidad en 22,9 % de los casos, se asociaron con la atención de salud en 38,1 % y se adquirieron durante la estancia hospitalaria en 39 %. Los pacientes con aislamientos multirresistentes desarrollaron con más frecuencia choque séptico (p=0,05), y presentaron peor función hepática y alta mortalidad durante la estancia hospitalaria (p=0,017). El ingreso previo, el uso de antibióticos en los 60 días anteriores, la adquisición de la infección en el hospital o asociada a un ingreso reciente y el aislamiento de bacterias en los cultivos de control, se determinaron como posibles factores de riesgo para el desarrollo de la infección multirresistente. Discusión. Los resultados del estudio confirmaron que el espectro microbiológico de las infecciones bacterianas en pacientes con cirrosis ha sufrido importantes cambios. Las infecciones por gérmenes multirresistentes causan infecciones con gran morbimortalidad y el fracaso del tratamiento antibiótico habitual. Para controlarlas de forma eficaz, es imprescindible detectar precozmente a aquellos pacientes con factores de riesgo.

Introduction: Bacterial infections represent a serious complication of liver cirrhosis. Traditionally, Gram negative bacteria have been described as the microorganisms responsible for the majority of the infections. However, in the past few years, changes in the microbiological spectrum have been described, and multiresistant bacteria are observed more frequently. Objective: To assess the proportion of patients with infections caused by multiresistant bacteria admitted to our hospital, and to obtain information about their epidemiology, risk factors and clinical impact. Materials and methods: We performed a retrospective evaluation of 294 cirrhotic patients admitted to our unit due to infection between June, 2011, and June, 2013. Results: We isolated 310 microorganisms from 294 patients; 109 (35.2%) were Gram positive, 167 (53.9%), Gram negative, and 34, fungi (11%). As for the microbiological agents, the most frequent was Escherichia coli (98 isolations). The infection was community-acquired in 22.9% of cases, healthcare-associated in 38.1% and nosocomial in 39%. Worse liver infections and septic shock were more frequent among patients with multiresistant isolates (p=0.05); and intrahospital mortality was also higher among them (p=0.017). Previous hospital admission, antibiotic treatment 60 days before, nosocomial or healthcare-associated acquisition and bacterial isolation in control cultures were identified as possible risk factors for the development of multiresistant infection. Discussion: The results of our study confirm that important changes have ocurred in the microbiological spectrum of bacterial infections in patients with liver cirrhosis. Multiresistant bacteria are associated with high morbidity and mortality, as well as failure of traditional antibiotic treatment. Successfull control of the infection requires an early identification of patients at risk.