Neumonía neumocócica bacteriémica en adultos en hospital regional de Chile / Bacteremic pneumococcal pneumonia in adults admitted to a general hospital: experience in 60 cases

Background: Bacteremic pneumococcal pneumonia (BPP) is a preventable disease with high morbimortality. Aim: To evaluate clinical aspects and mortality on BPP patients admitted to a Chilean regional hospital. Patients and Methods: We looked for adult patients with Streptococcus pneumoniae isolated from blood cultures between 2010 and 2014 years and reviewed clinical records of those who were admitted with pneumonia. Results: We identified 70 BPP patients: 58% were men, mean age was 56 years, 30% were > 65 years, 70% with basic public health insurance, 26% were alcoholics, 86% had comorbidities. Only two patients were vaccinated against S. pneumoniae. CURB-65 severity index for community acquired pneumonia was > 3 in 37% of patients. Twenty-four patients were admitted to ICU, twenty required mechanical ventilation and twenty-four died (34%). Mortality was associated with an age over 65 years, presence of comorbidities and complications of pneumonia. A total of 22 serotypes of S. pneumoniae were identified, five of them (1,3,7F,14 y 9V) were present in 57% of cases. Conclusions: Elevated mortality of our BNN patients was associated with comorbidities and possibly with socio economic factors, which conditioned a late access to medical care.

Septic Pulmonary Embolism Requiring Critical Care: Clinicoradiological Spectrum, Causative Pathogens and Outcomes

OBJECTIVES: Septic pulmonary embolism is an uncommon but life-threatening disorder. However, data on patients with septic pulmonary embolism who require critical care have not been well reported. This study elucidated the clinicoradiological spectrum, causative pathogens and outcomes of septic pulmonary embolism in patients requiring critical care. METHODS: The electronic medical records of 20 patients with septic pulmonary embolism who required intensive care unit admission between January 2005 and December 2013 were reviewed. RESULTS: Multiple organ dysfunction syndrome developed in 85% of the patients, and acute respiratory failure was the most common organ failure (75%). The most common computed tomographic findings included a feeding vessel sign (90%), peripheral nodules without cavities (80%) or with cavities (65%), and peripheral wedge-shaped opacities (75%). The most common primary source of infection was liver abscess (40%), followed by pneumonia (25%). The two most frequent causative pathogens were Klebsiella pneumoniae (50%) and Staphylococcus aureus (35%). Compared with survivors, nonsurvivors had significantly higher serum creatinine, arterial partial pressure of carbon dioxide, and Acute Physiology and Chronic Health Evaluation II and Sequential Organ Failure Assessment scores, and they were significantly more likely to have acute kidney injury, disseminated intravascular coagulation and lung abscesses. The in-hospital mortality rate was 30%. Pneumonia was the most common cause of death, followed by liver abscess. CONCLUSIONS: Patients with septic pulmonary embolism who require critical care, especially those with pneumonia and liver abscess, are associated with high mortality. Early diagnosis, appropriate antibiotic therapy, surgical intervention and respiratory support are essential.

Efecto del tratamiento antibiótico inicial adecuado sobre la mortalidad en pacientes en estado crítico con bacteriemia por Pseudomonas aeruginosa / Effect of adequate initial antimicrobi al therapy on mortality in critical patients with Pseudomonas aeruginosa bacteremia

Introducción. La bacteriemia es una de las infecciones hospitalarias de mayor mortalidad, especialmente en las unidades de cuidados intensivos, donde es más frecuente. Pseudomonas aeruginosa es uno de los causantes de bacteriemia más agresivos. Objetivo. Evaluar la asociación entre el tratamiento antibiótico inicial y la mortalidad hospitalaria en estos pacientes. Materiales y métodos. Se trata de un estudio de cohorte retrospectivo multicéntrico realizado entre 2005 y 2008. Se consideró tratamiento adecuado aquel iniciado en las primeras 48 horas del diagnóstico que incluyera, al menos, una dosis de antibiótico intravenoso al que P. aeruginosa fuera sensible y hubiera sido suministrado en la dosis y frecuencia recomendadas. El desenlace principal fue la mortalidad hospitalaria en un lapso de 30 días. Se hizo pareo según grado de exposición usando índices de propensión y, posteriormente, análisis paramétrico de supervivencia. Resultados. Se incluyeron 164 pacientes. La mediana de edad y la clasificación del APACHE II ( Acute Physiology and Chronic Health Evaluation II ) fue de 56 y 13, respectivamente. Se identificó la fuente de la bacteriemia en 68,3 % de los casos, y la más frecuente fue el tracto respiratorio; 44 % de los pacientes recibió tratamiento inadecuado, y la resistencia bacteriana fue la principal variable asociada. La proporción de incidencia de sepsis grave, choque séptico, falla orgánica múltiple y muerte en el lapso de 30 días fue de 67,7, 50, 41,5 y 43,9 %, respectivamente. El tratamiento adecuado se asoció a una prolongación del tiempo hasta el evento (razón de tiempo ajustada, 2,95, IC 95%, 1,63 a 5,33). Conclusión. El tratamiento antibiótico inicial adecuado es un factor protector contra la mortalidad hospitalaria en pacientes con bacteriemia por P. aeruginosa .

Introduction: Among hospital-acquired infections, bacteremia is one of the leading causes of mortality worldwide, especially among intensive care unit patients, where it is more frequent. Pseudomonas aeruginosa is one of the most aggressive agents causing bacteremia. Objective: To evaluate the association between initial antimicrobial therapy and hospital mortality in these patients. Materials and methods: A multicenter and retrospective cohort study was conducted between 2005 and 2008. Antimicrobial therapy was considered adequate if it included at least one intravenous antibiotic to which the P. aeruginosa isolate was susceptible in vitro, was administered at the recommended dose and frequency for bacteremia, and initiated within the first 48 hours from diagnosis. The main outcome was 30-day hospital mortality. Patients were paired according to exposure level using propensity score matching, and then a parametric survival model was fitted. Results: One hundred and sixty four patients were included. Median age and the APACHE II score were 56 and 13, respectively. The source of bacteremia was identified in 68.3 % of cases, the respiratory tract being the most frequent. Forty-four percent of patients received inadequate therapy, with bacterial resistance as the main associated variable. The incidence of severe sepsis, septic shock, multiple organ failure and death within the first 30 days was 67.7, 50, 41.5 and 43.9%, respectively. Adequate therapy was associated with a longer time to the event (adjusted time ratio, 2.95, 95% CI, 1.63 to 5.33). Conclusion: Adequate initial antimicrobial therapy is a protective factor against hospital mortality in patients with P. aeruginosa bacteremia.

Factors influencing the early mortality in haematological malignancy patients with nosocomial Gram negative bacilli bacteraemia: a retrospective analysis of 154 cases

BACKGROUND: The aim of this study is to assess the factors influencing the early mortality (7- day after index blood culture) in haematological malignancy patients with Gram negative bacilli (GNB) bacteraemia. METHODS: Infection control committee records were reviewed to identify the cases between March 2006 and June 2011. Only one bacteraemic episode per patient was included in the study. RESULTS: A total of 154 patients with GNB bacteraemia were identified. The early mortality rate was 19.5% (30 out of 154). Blood cultures revealed Enterobacteriacea in 120 patients (Escherichia coli; 86, Klebsiella spp.; 28, Enterobacter cloacea; 6) and glucose non-fermenting GNB in 34 patients (Pseudomonas aeruginosa; 15, Acinetobacter baumannii; 11, Stenotrophomonas maltophilia; 7, Burkholderia cepacia; 1). Forty (33.3%) out of 120 Enterobacteriaceae were extended spectrum beta-lactamase (ESBL) producers and 18 (52.9%) out of 34 glucose non-fermenting GNB were multidrug resistant. Carbapenems were administered as first line therapy in 139 out of 154 patients. In univariate analysis Pitt's bacteraemia score, presence of aplastic anaemia, bacteraemia caused by glucose non-fermentating GNB, inappropriate empirical antibacterial treatment, presence of severe sepsis or septic shock, unable to achieve microbiological cure, and intensive care unit (ICU) acquired bacteraemia were associated with mortality. Multivariate analysis showed ICU acquired bacteraemia (OR, 12.55; 95% CI, 2.34-67.38, p = 0.003) as an independent factor associated with early mortality. CONCLUSION: Haematological malignancy patients who require ICU care are at high risk for early mortality related to GNB bacteraemia. Based on the local findings pointing out high rate of multidrug resistance, carbapenems combined with colistin seems to be a reasonable approach as empirical treatment of these patients. However, increasing carbapenem resistance rate is of concern.

Colangitis bacteriémica en adultos en un hospital general en Chile / Bacteremic colangitis in adults in a general hospital in Chile

Background: Some aspects of bacteremic cholangitis are unknown in Chile. Aim: To gather more information on clinical, microbiological aspects as well as risk factors for ICU admission, recurrence and antimicrobial resistance. Material and Methods: A retrospective research was performed using medical records of adult patients in a general hospital. Results: Between 2006-2012, 22 patients with 29 bacteremic events were identified. Previous cholangitis events were reported by 27.3%, 45.5% had recent admissions and, 50% had used antimicrobial compounds. Coledocholithiasis was the most common cause of obstruction (45.5%) followed by cancer (36.4%). One third developed shock (31%), the only factor associated with ICU admission (OR 30, p < 0.05). In 24 of the 29 bacteremic events, the biliary tract was intervened (82.8%) and in 80.8% during the first 72 hours. Gram negative bacilli were predominant (> 80%) and some infrequent agents such as Staphylococcus warneri, Shewanella spp. and, Aeromonas spp. were observed. Among enteric gram negative bacilli, 29.2% presented fluoroquinolone resistance and, 26.1% resistance to third generation cephalosporins, both associated with previous endoscopic retrograde cholangiography (OR 35 and 16.5, respectively p < 0.05). A favorable response was observed in 93.1% of bacte-remic events but in 31.8% of patients cholangitis recurred with or without bacteremia. Recurrence was associated to recent admission (OR 16.5, p = 0.01) and in all cases occurred before 81 days. In-hospital mortality was 9.1% (n = 2), but in only one case associated to sepsis. Average length of stay (LOS) was 17.8 days. Conclusions: Early intervention of the biliary tract allows a favorable response in patients affected by bacteremic cholangitis, but this condition use intensive care resources, had a prolonged LOS, a recurrent pattern, and is associated with several bacterial species, some of them resistant.

Introducción: La información sobre los cuadros de colangitis aguda bacteriémica es fragmentaria en Chile. Objetivo: Analizar las características clínicas, evolución, microbiología y factores de riesgo asociados a ingreso a UCI, recurrencia y resistencia antimicrobiana. Pacientes y Métodos: Estudio retrospectivo descriptivo con adultos atendidos entre el 2006 y el 2012 en un hospital general. Resultados: Se identificaron 22 pacientes con 29 episodios de bacteriemia. Un 27,3% tenía historia previa de colangitis aguda, 45,5% de hospitalizaciones en los últimos tres meses y 50% recibió previamente antimicrobianos. La coledocolitiasis fue la causa más frecuente de obstrucción (45,5%) y las neoplasias ocuparon el segundo lugar (36,4%). El 31% desarrolló shock hemodinámico y fue el factor determinante para ingresar a la UCI (OR 30, p < 0,01) En 24 de los 29 eventos de colangitis bacteriémica se efectuaron intervenciones sobre la vía biliar (VB) o complicaciones asociadas (82,8%), las que se realizaron predominantemente en las primeras 72 h de hospitalización (80,8%). Las especies bacterianas mayoritarias fueron bacilos gramnegativos entéricos o no fermentadores (> 80% del total) y se observaron agentes inusuales como Staphylococcus warneri, Shewanella spp y Aeromonas spp. Entre los bacilos gramnegativos entéricos, 29,2% presentó resistencia a fluoroquinolonas y 26,1 % a cefalosporinas de tercera generación, fenómenos asociados al antecedente de colangiografía endoscópica retrógrada (OR 35 y 16,5 respectivamente, p < 0,05). El 93,1% de los eventos de bacteriemia tuvo una respuesta favorable pero 31,8% de los pacientes presentó recu-rrencia de colangitis, con o sin bacteriemia, un hecho asociado a hospitalización reciente (OR 16,5, p = 0,01) y que se dio en todos los casos antes de 81 días. Dos pacientes con cáncer fallecieron en la misma hospitalización (9,1%), aunque uno solo de ellos en forma atribuible a la infección. La estadía hospitalaria promedio fue de 17,8 días. Conclusiones: Con la intervención precoz sobre la VB, los cuadros de colangitis bacteriémica han logrado una baja letalidad pero usan recursos intensivos, tienen una estadía prolongada, un patrón recurrente, pueden estar asociados a cáncer y a una diversidad de agentes bacterianos, algunos de ellos resistentes.

Healthcare-associated Staphylococcus aureus bloodstream infection: length of stay, attributable mortality, and additional direct costs

This study aimed to determine the excess length of stay, extra expenditures, and attributable mortality to healthcare-associated S. aureus bloodstream infection (BSI) at a teaching hospital in central Brazil. The study design was a matched (1:1) case-control. Cases were defined as patients > 13 years old, with a healthcare-associated S. aureus BSI. Controls included patients without an S. aureus BSI, who were matched to cases by gender, age (± 7 years), morbidity, and underlying disease. Data were collected from medical records and from the Brazilian National Hospital Information System (Sistema de Informações Hospitalares do Sistema Único de Saúde - SIH/SUS). A Wilcoxon rank sum test was performed to compare length of stay and costs between cases and controls. Differences in mortality between cases and controls were compared using McNemar's tests. The Mantel-Haenzel stratified analysis was performed to compare invasive device utilization. Data analyses were conducted using Epi Info 6.0 and Statistical Package for Social Sciences (SPSS 13.0). 84 case-control pairs matched by gender, age, admission period, morbidity, and underlying disease were analyzed. The mean lengths of hospital stay were 48.3 and 16.2 days for cases and controls, respectively (p < 0.01), yielding an excess hospital stay among cases of 32.1 days. the excess mortality among cases compared to controls that was attributable to s. aureus bloodstream infection was 45.2%. Cases had a higher risk of dying compared to controls (OR 7.3, 95% CI 3.1-21.1). Overall costs of hospitalization (SIH/SUS) reached US$ 123,065 for cases versus US$ 40,247 for controls (p < 0.01). the cost of antimicrobial therapy was 6.7 fold higher for cases compared to controls. healthcare-associated s. aureus BSI was associated with statistically significant increases in length of hospitalization, attributable mortality, and economic burden. Implementation of measures to minimize the risk of healthcare-associated bacterial infections is essential.

Impacto de la bacteriemia en una cohorte de pacientes con neumonía neumocócica / Impact of bacteremia in a cohort of patients with pneumococcal pneumonia

OBJETIVO: Bacteriemia es la forma invasiva más común de neumonía adquirida en la comunidad (NAC) por Streptococcus pneumoniae. Investigamos si la bacteriemia en NAC neumocócica empeora los resultados y si ella guarda relación con la vacunación antineumocócica (VAN). MÉTODOS: Análisis secundario de una cohorte de pacientes con NAC neumocócica confirmada por cultivo de sangre o esputo o antígeno urinario. Se registraron datos demográficos, clínicos, radiográficos y de laboratorio, escores Acute Physiology and Chronic Health Evaluation II (APACHE II) y pneumonia severity index (PSI), comorbilidades y antecedente de VAN. Se compararon pacientes con NAC neumocócica bacteriémica (NNB) vs. no bacteriémica (NNNB). RESULTADOS: Cuarenta y siete pacientes tenían NNB y 71 NNNB (45 por cultivo de esputo y 26 por antígeno urinario); 107 tenían alguna indicación de VAN. Ningún paciente con NNB, pero 9 con NNNB, habían recibido VAN (p = 0,043). Los pacientes con NNB eran mayores (76,4 ± 11,5 vs. 67,5 ± 20,9 años), tenían mayor APACHE II (16,4 ± 4,6 vs. 14,1 ± 6,5) y PSI (129,5 ± 36 vs. 105,2 ± 45), más frecuentemente cardiopatía e insuficiencia renal crónica e internación en UTI (42,5% vs. 22,5%) y menor hematocrito (35,7 ± 5,8 vs. 38,6 ± 6,7%) y sodio plasmático (133,9 ± 6,0 vs. 137,1 ± 5,5 mEq/L). La mortalidad fue similar (29,8% vs. 28,2%). CONCLUSIONES: Los niveles de VAN (8,4%) en esta población con alto riesgo de NAC por S. pneumoniae fueron extremadamente bajos. Los pacientes con NNB estaban más graves, pero la mortalidad fue similar entre los dos grupos. La VAN reduce la incidencia de NNB y es razonable incrementar el nivel de vacunación de la población en riesgo.

OBJECTIVE: Bacteremia is the most common presentation of invasive disease in community-acquired pneumonia (CAP) due to Streptococcus pneumoniae. We investigated whether bacteremia in pneumococcal CAP worsens outcomes and whether it is related to pneumococcal vaccination (PV). METHODS: Secondary analysis of a cohort of patients with pneumococcal CAP confirmed by blood culture, sputum culture, or urinary antigen testing. Demographic, clinical, radiographic, and biochemical data were collected, as were Acute Physiology and Chronic Health Evaluation II (APACHE II) and pneumonia severity index (PSI) scores, comorbidities, and PV history. We drew comparisons between patients with bacteremic pneumococcal CAP (BPP) and those with non-bacteremic pneumococcal CAP (NBPP). RESULTS: Forty-seven patients had BPP, and 71 had NBPP (confirmed by sputum culture in 45 and by urinary antigen testing in 26); 107 had some indication for PV. None of the BPP patients had received PV, compared with 9 of the NBPP patients (p = 0.043). Among the BPP patients, the mean age was higher (76.4 ± 11.5 vs. 67.5 ± 20.9 years), as were APACHE II and PSI scores (16.4 ± 4.6 vs. 14.1 ± 6.5 and 129.5 ± 36 vs. 105.2 ± 45, respectively), as well as the rate of ICU admission for cardiopathy or chronic renal failure (42.5% vs. 22.5%), whereas hematocrit and plasma sodium levels were lower (35.7 ± 5.8 vs. 38.6 ± 6.7% and 133.9 ± 6.0 vs. 137.1 ± 5.5 mEq/L, respectively), although mortality was similar (29.8% vs. 28.2%). CONCLUSIONS: In this population at high risk for CAP due to S. pneumoniae, the PV rate was extremely low (8.4%). Although BPP patients were more severely ill, mortality was similar between the two groups. Because PV reduces the incidence of BPP, the vaccination rate in at-risk populations should be increased.

Risk factors for pan-resistant Pseudomonas aeruginosa bacteremia and the adequacy of antibiotic therapy

INTRODUCTION: The aim of this study was to determine risk factors for acquiring carbapenemresistant Pseudomonas aeruginosa bacteremia (CR-PA) and factors associated with in-hospital mortality. METHODS: Seventy-seven cases of bacteremia caused by P. aeruginosa were evaluated in a hospital with high incidence of CR-PA. Clinical and laboratorial factors, and previous use of antibiotics were also evaluated. In one analysis, CR-PA and carbapenem-susceptible P. aeruginosa (CS-PA) bacteremia were compared. A second analysis compared patients who died with survivors. RESULTS: Among 77 P. aeruginosa bacteremia, 29 were caused by CR-PA. Admission to the intensive care unit, higher number of total leukocytes, and previous use of carbapenem were statistically associated with CR-PA. In the multivariate analysis, only previous use of carbapenem (including ertapenem) turned out to be a risk factor for CR-PA (p = 0.014). The 30-day mortality of patients with P. aeruginosa bloodstream infection was 44.8% for CS-PA and 54.2% for patients with CR-PA (p = 0.288). Chronic renal failure, admission to the intensive care unit, mechanical ventilation, and central venous catheter were risk factors for mortality. Incorrect treatment increased mortality of patients with bacteremia caused by CS-PA, but not for CR-SA. The odd ratio of mortality associated with incorrect therapy in patients with CS-PA was 3.30 (1.01-10.82; p = 0.043). The mortality of patients with bacteremia caused by CR-PA was unexpectedly similar regardless of antimicrobial treatment adequacy. CONCLUSION: Appropriate treatment for CS-PA bacteremia initiated within the first 24 hours was associated with lower mortality, but this cannot be extrapolated for CR-PA.

Incidencia y mortalidad de bacteriemia en un hospital clínico docente en Santiago de Chile / Incidence and mortality of bacteremia in a public hospital in Santiago

Background:The incidence of bacteremia has increased over the last decade due to the aging of the population and the wide implementation of invasive nosocomial procedures and wide-spectrum antimicrobial treatments. Aim: To assess the epidemiology of hospital and ambulatory bacteremias in a public hospital in Santiago. Material and Methods: A prospective longitudinal cohort study of laboratory-confirmed adult patients with bacteremia was undertaken at a public hospital in Santiago, between June 1, 2007 and April 30, 2008. Demographic, clinical, and laboratory data was collected into a standardized study-specific form. Results: In the study period, 253 cases of true bacteremia were identified, with an incidence of 11 per 1,000 patient discharges (63.6% nosocomial, 36.7% fatal). Only 2/3 of the cohort was alive at day 28 of hospitalization. Variables associated with mortality were age with a hazard ratio (HR) of 2.31; (95% confidence intervals (CI) 1.42- 3.77); female gender (HR, 1.70; 95% CI 1.06- 2.71); shock (HR, 3.24; 95%CI 2.01-5.22); and C reactive protein (HR, 2.10; 95% CI 1.17- 3.78). The variable associated with lower mortality was surgery (HR, 0.43; 95% CI 0.25-0.75). Selective empiric treatment did not improve survival. Conclusions: Besides age and gender, survival can be influenced by modifiable variables such as presence of shock and surgical intervention, which may provide an opportunity to improve outcomes.

Methicillin-resistant Staphylococcus aureus bloodstream infection: risk factors and clinical outcome in non-intensive-care units / Infecção de corrente sanguínea por Staphylococcus aureus resistente à meticilina: fatores de risco e evolução clínica em unidades não críticas

INTRODUCTION: Methicillin-resistant Staphylococcus aureus (MRSA) is spread out in hospitals across different regions of the world and is regarded as the major agent of nosocomial infections, causing infections such as skin and soft tissue pneumonia and sepsis. The aim of this study was to identify risk factors for methicillin-resistance in Staphylococcus aureus bloodstream infection (BSI) and the predictive factors for death. METHODS: A retrospective cohort of fifty-one patients presenting bacteraemia due to S. aureus between September 2006 and September 2008 was analysed. Staphylococcu aureus samples were obtained from blood cultures performed by clinical hospital microbiology laboratory from the Uberlândia Federal University. Methicillinresistance was determined by growth on oxacillin screen agar and antimicrobial susceptibility by means of the disk diffusion method. RESULTS: We found similar numbers of MRSA (56.8%) and methicillin-susceptible Staphylococcus aureus (MSSA) (43.2%) infections, and the overall hospital mortality ratio was 47%, predominantly in MRSA group (70.8% vs. 29.2%) (p=0.05). Age (p=0.02) was significantly higher in MRSA patients as also was the use of central venous catheter (p=0.02). The use of two or more antimicrobial agents (p=0.03) and the length of hospital stay prior to bacteraemia superior to seven days (p=0.006) were associated with mortality. High odds ratio value was observed in cardiopathy as comorbidity. CONCLUSIONS: Despite several risk factors associated with MRSA and MSSA infection, the use of two or more antimicrobial agents was the unique independent variable associated with mortality.

INTRODUÇÃO: Methicillin-resistant Staphylococcus aureus (MRSA), se disseminou nos hospitais em diferentes regiões do globo, e é atualmente o principal agente de infecções hospitalares causando infecções de pele, tecidos moles, pneumonia e sepse. O objetivo deste estudo foi identificar fatores de risco para resistência à meticilina em infecções de corrente sanguínea por Staphylococcus aureus e fatores preditivos de mortalidade. MÉTODOS: Uma coorte de 51 pacientes apresentando bacteremia por S. aureus, entre setembro de 2006 a setembro de 2008 foi analisada. Amostras de S. aureus foram obtidas a partir de hemoculturas realizadas pelo laboratório de microbiologia do hospital de clínicas da Universidade Federal de Uberlândia. A resistência à meticilina foi determinada pelo crescimento no agar triagem para oxacilina e a sensibilidade aos antimicrobianos pelo método de difusão em agar. RESULTADOS: Infecções por MRSA (56,8%) e methicillin-susceptible Staphylococcus aureus (MSSA) (43,2%) foram similares e a taxa de mortalidade hospitalar foi de 47%, predominantemente no grupo infectado por MRSA (70,8% vs. 29,2%) (p=0,05). Idade (p=0,02) e a presença de cateter vascular central (p=0,02) foram significantes no grupo de infectados por MRSA. A evolução demonstrou que o uso de dois ou mais agentes antimicrobianos (p=0,03) e tempo de internação prévio à bacteremia superior a sete dias (p=0,006) foram associados à morte. Altos valores de odds ratio foram observados para cardiopatia como comorbidade. CONCLUSÕES: Embora vários fatores de risco tenham sido associados a infecções por MRSA e MSSA e mortalidade o uso de dois ou mais agentes antimicrobianos foi a única variável independente para mortalidade.

Klebsiella ESBL bacteremia-mortality and risk factors

Background: Extended spectrum β-lactamase (ESBL)-producing bacteria have become recognized as a problem in South America. The aim of this study was to evaluate risk factors and mortality rate in bacteremia caused by ESBL-producing Klebsiella pneumoniae in a Brazilian hospital. Methods: A three-year retrospective cohort study with 104 cases of K. pneumoniae bacteremia (61 ESBL and 43 non-ESBL). Several clinical and laboratory variables were evaluated. The outcome of interest was 30-day mortality. The adequate treatment was evaluated according to antibiotic susceptibility. Results: Multivariable analysis showed that central venous catheter and mechanical ventilation were independent risk factors for ESBL. The duration of hospitalization before the bacteremia was not a risk factor. Mortality was similar in ESBL and non-ESBL and inadequate therapy was not shown to be a risk factor. Conclusion: ESBL-producing Klebsiella bacteremia can occur early, suggesting that a carbapenem should be included in the initial empirical therapy for bacteremia in patients under mechanical ventilation and/or central venous catheter in our institution.

Bacteriemia en daño hepático crónico / Bacteremia in patients with liver cirrhosis

Las infecciones bacteriémicas son más frecuentes en el paciente cirrótico que en la población general. Se identificaron retrospectivamente 59 pacientes cirróticos con bacteriemia, hospitalizados entre los años 2005 y 2008. La bacteriemia sin foco fue la más frecuente (29 por ciento), seguida de aquellas de origen pulmonar (22 por ciento). Cincuenta y dos por ciento de los agentes aislados correspondieron a cocáceas grampositivas y 48 por ciento a bacilos gramnegativos, siendo estos últimos los agentes predominantes en las bacteriemias nosocomiales. Los principales agentes aislados fueron Staphylococcns aureus (24 por ciento) y Escherichia col i (22 por ciento). La mortalidad de los pacientes cirróticos bacteriémicos fue mayor que la del total de cirróticos hospitalizados (37 vs 9,4 por ciento; p < 0,001) y la medición del puntaje de MELD a las 72 horas se correlacionó significativamente con la mortalidad. Conclusión: La bacteriemia es una complicación grave del paciente cirrótico y el MELD podría ser útil en su categorización de riesgo.

Bacteremic infections are more frequent in patients with cirrhosis, as their immune system is compromised. Series of cirrhotic patients with bacteremia has seldom been reported in Chile. We retrospectively collected, from 2005 to 2008, 59 episodes of bacteremia in cirrhotics representing 9 percent of the overall number of bacteremic episodes seen in our center in the period. Spontaneous bacteremia accounted for 29 percent followed by those of pulmonary origin (22 percent). Grampositive cocci and gramnegative bacilli were responsible in 52 percent and 48 percent respectively, however gramnegative rods predominated in nosocomial bacteremias. Overall, the most frequent organisms were Staphylococcus aureus (24 percent) and Escherichia col i (22 percent). Mortality in bacteremic patients was significantly higher compared with all cirrhotic patients hospitalized in the period (37.0 vs 9.4 percent; p < 0.001) and MELD score was significantly correlated with mortality. Conclusion: bacteremia is a severe complication of cirrhosis and MELD score could be a useful tool to stratify risk in these patients.

Impacto de la resistencia a la meticilina sobre la mortalidad y vigilancia de la sensibilidad a la vancomicina en bacteriemias causadas por Staphylococcus aureus / Impact of methicillin resistance on mortality and surveillance of vancomycin susceptibility in bacteremias caused by Staphylococcus aureus

Staphylococcus aureus es uno de los principales patógenos nosocomiales y produce una alta morbimortalidad en numerosos hospitales del mundo. Además, la incidencia de bacteriemias por este microorganismo ha aumentado significativamente en las últimas décadas. Los objetivos del presente trabajo fueron identificar los factores de riesgo que favorecen la aparición de resistencia a la meticilina en aislamientos de S. aureus y los factores que afectan la mortalidad por bacteriemias asociadas a este patógeno, así como evaluar la sensibilidad a la vancomicina de las cepas resistentes a la meticilina. Se estudiaron 39 aislamientos de S. aureus provenientes de hemocultivos de pacientes internados con bacteriemia en la Nueva Clínica Chacabuco de Tandil (Pcia. de Buenos Aires, Argentina) en el período 01/2006-12/2008. La mortalidad global fue del 51,3% y estuvo significativamente asociada con la resistencia a la meticilina (OR: 4,20; IC95%: 1,08-16,32; p: 0,05); aunque dicho factor no fue un predictor independiente de mortalidad. La cirugía previa (OR: 17,23; IC95%: 1,80-164,60) y la estancia previa en la unidad de cuidados intensivos (OR: 21,12; IC95%: 2,33-191,30) fueron predictores independientes de la resistencia a la meticilina y la asistencia respiratoria mecánica (OR: 15,99; IC: 3,24-78,86) fue un predictor independiente de la mortalidad. No se detectaron cepas con sensibilidad disminuida a la vancomicina. Todos los aislamientos estudiados fueron sensibles in vitro a la vancomicina, con una CIM50 y una CIM90 de 0,5 μg/ml.

Staphylococcus aureus is a major nosocomial pathogen that causes severe morbidity and mortality in many hospitals worldwide. Besides, the incidence of S. aureus bacteremia has significantly increased over the past decades. The aims of this study were to detect the risk factors for methicillin resistance and mortality and to evaluate vancomycin susceptibility in methicillin-resistant isolates. Thus, 39 S. aureus isolates from blood cultures of hospitalized patients with bacteremia were studied in Nueva Clínica Chacabuco Tandil, Buenos Aires, Argentina during 01/2006-12/2008. The overall mortality was 51.3%, which was significantly associated with methicillin resistance (OR: 4.20, IC95%: 1.08-16.32, p: 0.05), even though it was not an independent mortality predictor as it was the mechanical ventilation (OR: 15.99, IC95%: 3.24 - 78.86). Previous surgery (OR: 17.23, IC95%: 1.80-164.60) and hospitalization in intensive care units (OR: 21.12, IC95%: 2.33-191.30) were independent predictors of meticillin-resistance. No isolates were found with reduced vancomycin susceptibility. All the studied isolates were in vitro susceptible to vancomycin with a MIC50 and MIC90 of 0.5 μg/ml.

Factores pronósticos, evolución y mortalidad en el adulto inmunocompetente hospitalizado por neumonía neumocócica adquirida en la comunidad / Prognostic factors and mortality in immunocompetent adult patients hospitalized with community-acquired pneumococcal pneumonia

Background: Streptococcus pneumoniae is the main cause of community-acquired pneumonia in adults. Aim: To describe baseline characteristics, risk factors and clinical outcomes of adult patients hospitalized with pneumococcal pneumonia. Material and methods: Prospective study of adult patients admitted for a community acquired pneumonia in a clinical hospital. Immune deficient patients and those with a history of a recent hospitalization were excluded. Results: One hundred fifty one immuno-competent patients, aged 16 to 92 years, 58 percent males, were studied. Seventy-five percent had other diseases, 26 percent were admitted to the intensive care unit and 9 percent needed mechanical ventilation. There were no differences in clinical features, ICU admission or hospital length of stay among bacteremic and non-bacteremic patients. Thirty days lethality for bacteremic and non-bacteremic patients was 10.9 percent and 11.5 percent, respectively. The predictive values for lethality of Fine pneumonia severity index and CURB-65 (Confusion, Urea nitrogen, Respiratory rate, Blood pressure, 65 years of age and older) had an area under the ROC curve of 0.8 and 0.69, respectively. Multivariate analysis disclosed blood urea nitrogen over 30 mg/ dL (odds ratio (OR), 6.8), need for mechanical ventilation (OR, 7.4) and diastolic blood pressure below 50 mmHg (OR, 3.9), as significant independent predictors of death. Conclusions: Pneumococcal pneumonia was associated with a substantial rate of complications and mortality. Clinical presentation and outcome did not differ significantly among patients with and without bacteremia.

Epidemiología y factores de riesgo de mortalidad de las bacteriemias intrahospitalarias por bacilos gramnegativos / Nosocomial bloodstream infections caused by gram-negative bacilli: epidemiology and risk factors for mortality

Nosocomial bacteremia is a major cause of hospital infection, associated with high rate of morbidity and mortality, prolonged hospital stay and higher costs. However, few prospective studies analyse the prognostic factors associated with mortality of gramnegative rods bloodstream infections in hospital wards outside of intensive care units. A prospective/descriptive study was conducted from March to December 2006. All patients with nosocomial-acquired bloodstream infection due to gramnegative rods were included. Epidemiology and clinical features were analysed as potential prognostic factors for mortality. During the study period, 84 cases were detected, being A. baumannii, Burkholderia sp and E. coli the most frequent isolates, with a mortality of 48 percent>. Bacteremia derived from a high-mortality associated septic focus (RR 4.9, IC95 percent> 1.3 - 18.8) and admissionto intensive care unit (RR 4.78, IC95 percent> 1.7- 13.1) were independent variables associated with mortality. Inappropriate empirical antibiotic treatment was not associated with greater risk of mortality. Nosocomial gramnegative bloodstream infections in our series were mainly due to non-fermentative bacilli and were associated with high mortality rates when their origin was a high risk septic focus or the patient was admitted to intensive care unit.

La bacteriemia nosocomial es una causa importante de infección intrahospitalaria, asociada a alta morbi-mortalidad, pero pocos estudios examinan en forma prospectiva las bacteriemias por bacilos grammne-gativos (BGN) más allá de las áreas de cuidados intensivos. Se realizó un estudio descriptivo, prospectivo desde marzo a diciembre del 2006, reclutando todos los pacientes con bacteriemia por BGN de origen intra-hospitalario. Se analiza la epidemiología y características clínicas como potenciales factores pronósticos de mortalidad. En el período de estudio se detectaron 84 casos (los más frecuentes A. baumannii, Burkholderia sp. y E. coli), con una mortalidad de 48 por ciento. La bacteriemia derivada de un foco infecciosos asociada a alta mortalidad (RR 4.9, IC95 por ciento 1,3-18,8) y la internación en UCI (RR 4,78, IC95 por ciento 1,7-13,1) fueron variables independientes predictoras de mortalidad. El tratamiento antimicrobiano empírico inadecuado no se asoció a mayor mortalidad. La bacteriemia nosocomial por BGN en nuestra serie se debió principalmente a bacilos no fermentadores y ésta se asoció con alta mortalidad cuando el origen fue un foco de alto riesgo o el paciente se encontraba internado en la UCI.

Staphylococcus aureus bacteremia: what is the impact of oxacillin resistance on mortality?

In order to analyse the impact of oxacillin resistance on the mortality of Staphylococcus aureus bacteremia, and to assess the antimicrobial susceptibility of community-acquired strains in two large university hospitals (the Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo and the Instituto Central do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo), we carried out a four-month-long prospective cohort study, which included 163 consecutive cases of S. aureus bacteremia. Of these, 140 (85.9 percent) were hospital-acquired, 9 (5.5 percent) were community-acquired and 14 (8.6 percent) were of indeterminate origin. No cases of community-acquired infection by oxacillin-resistant S. aureus was identified. Among hospital-acquired infections, oxacillin-resistant S. aureus was responsible for 64.3 percent of cases. Mortality up to 15 days after diagnosis of bacteremia was 27 percent (18/67) for infections caused by susceptible strains and 33 percent (32/96) for infections caused by oxacillin-resistant strains (p=0.10). The following independent risk factors for the acquisition of oxacillin-resistant S. aureus were identified in multiple logistical regression analysis: age over 60 years, use of corticoids; presence of a central vascular catheter, and previous use of antibiotics.

Factores pronóstico y mortalidad asociada a bacteremias por bacilos gramnegativos / Mortality and prognostic factors associated to gramnegative bacillus bacteremia

La frecuencia de bacteremia por bacilos gramnegativos ha aumentado en forma importante en este siglo. La mortalidad asociada a este tipo de infecciones es alta y los factores asociados a éstas son múltiples. Realizamos un estudio retrospectivo, en el que se analizan diferentes factores relacionados con el huésped, el bacilo y el hospital que pudieran afectar la evolución del paciente. Se mostro que las bacteremias por Stenotrophomona maltophilia, el antecedente de neoplasia, el uso previo de carbapenémicos y el uso de nutrición parenteral total se asociaron a mayor mortalidad