Predictive factors for mortality in patients with methicillin-resistant Staphylococcus aureus bloodstream infection: impact on outcome of host, microorganism and therapy.

Mortality related to methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infection (BSI) remains high, despite changes in the epidemiology. To analyze the current predictive factors for mortality we conducted a prospective study in a large cohort of patients with MRSA-BSI from 21 Spanish hospitals. Epidemiology, clinical data, therapy and outcome were recorded. All MRSA strains were analysed, including susceptibility to antibiotics and molecular characterization. Vancomycin MICs (V-MIC) were tested by the E-test and microdilution methods. Time until death was the dependent variable in a Cox regression analysis. Overall, 579 episodes were included. Acquisition was nosocomial in 59% and vascular catheter was the most frequent source (38%). A dominant PFGE genotype was found in 368 (67%) isolates, which belonged to Clonal Complex (CC)5 and carried SCCmecIV and agr2. Microdilution V-MIC50 and V-MIC90 were 0.7 and 1.0 mg/L, respectively. Initial therapy was appropriate in 66% of episodes. Overall mortality was observed in 179 (32%) episodes. The Cox-regression analysis identified age >70 years (HR 1.88), previous fatal disease (HR 2.16), Pitt score >1 (HR 3.45), high-risk source (HR 1.85) and inappropriate initial treatment (HR 1.39) as independent predictive factors for mortality. CC5 and CC22 (HR 0.52 and 0.45) were associated with significantly lower mortality rates than CC8. V-MIC ≥1.5 did not have a significant impact on mortality, regardless of the method used to assess it.

Lung cavitation due to Mycobacterium xenopi in a renal transplant recipient.

Mycobacterium xenopi is an unusual pathogen and few such cases have been reported in the literature. We report the case of a patient with a sirolimus-based immunosuppressive regimen, who developed lung cavitation. M. xenopi was isolated from the sputum. The patient was treated initially with rifampicin, isoniazid, and pyrazinamide; levofloxacin was added to the treatment regimen after M. xenopi was demonstrated. A possible relationship between sirolimus and M. xenopi infection has been postulated, probably due to the combination of pulmonary toxicity and cellular immunosuppression of rapamycin.

Candidemia in a tertiary care hospital: epidemiology and factors influencing mortality.

The present study was conducted in order to assess the epidemiology and clinical course of candidemia and to identify the risk factors associated with mortality. A total of 143 episodes of nosocomial candidemia were identified during a 5-year period, and these were included in the study. The majority of candidemic episodes were due to Candida albicans (63, 44%), followed by Candida parapsilosis(32, 22%). The overall mortality was 45%. The following independent prognostic factors for mortality were identified: bacterial sepsis, rapidly fatal illness, chronic obstructive lung disease, presence of a central venous catheter, candidemia due to Candida albicans, and lack of antifungal therapy.

Incidencia de meningitis neumocócica en niños de 0 a 23 meses en Cantabria. Estudio retrospectivo 1997-2001 / Incidence of pneumococcal meningitis in children from 0 to 23 months in Cantabria. Retrospective study 1997-2001

Objetivo: Contribuir al conocimiento de la epidemiología de enfermedad neumocócica en nuestro país, y conocer la incidencia actual de la meningitis neumocócica en población infantil menor de 2 años en Cantabria. Pacientes y métodos: Estudio retrospectivo (1 de enero 1997 a 31 diciembre 2001), de los pacientes menores de 2 años ingresados en nuestro Servicio en los que se aisló el S. Pneumoniae en sangre y /o LCR asociado a signos clínicos y analíticos de meningitis bacteriana. Se revisaron las historias clínicas y se calculó las tasas de incidencia con intervalo de confianza al 95 por ciento en los distintos grupos de edad (0 a 11 meses y 0 a 23 meses). El número de niños y su distribución por edades se obtuvo del Movimiento Natural de las Población de Cantabria, del Instituto Nacional de Estadística (www.ine.es/tempus/cgi-bin/itie). El cálculo estadístico se realizó por el método exacto binomial. Resultados: En el período estudiado se detectaron 4 pacientes con meningitis neumocócica, todos ellos de edad inferior a 12 meses. La tasa de incidencia en el primer año de vida es de 20,13 (intervalo de confianza al 95 por ciento: 5,49- 51,54) y en el niño de 0 a 24 meses de 10,19 (intervalo de confianza al 95 por ciento: 2,78-26,12). Conclusiones: Nuestro estudio demuestra una incidencia elevada de meningitis neumococica en Cantabria, particularmente en el primer año de vida (20,13 casos por 100.000 habitantes). La tasa de incidencia, es similar a la encontrada en otros comunidades de nuestro país (AU)

Antimicrobial susceptibilities of 1,684 Streptococcus pneumoniae and 2,039 Streptococcus pyogenes isolates and their ecological relationships: results of a 1-year (1998-1999) multicenter surveillance study in Spain.

A nationwide multicenter susceptibility surveillance study which included 1,684 Streptococcus pneumoniae and 2,039 S. pyogenes isolates was carried out over 1 year in order to assess the current resistance patterns for the two most important gram-positive microorganisms responsible for community-acquired infections in Spain. Susceptibility testing was done by a broth microdilution method according to National Committee for Clinical Laboratory Standards M100-S10 interpretative criteria. For S. pneumoniae, the prevalences of highly resistant strains were 5% for amoxicillin and amoxicillin-clavulanic acid; 7% for cefotaxime; 22% for penicillin; 31% for cefuroxime; 35% for erythromycin, clarithromycin, and azithromycin; and 42% for cefaclor. For S. pyogenes, the prevalence of erythromycin resistance was 20%. Efflux was encountered in 90% of S. pyogenes and 5% of S. pneumoniae isolates that exhibited erythromycin resistance. Erythromycin resistance was associated with clarithromycin and azithromycin in both species, regardless of phenotype. Despite the different nature of the mechanisms of resistance, a positive correlation (r = 0.612) between the two species in the prevalence of erythromycin resistance was found in site-by-site comparisons, suggesting some kind of link with antibiotic consumption. Regarding ciprofloxacin, the MIC was >or=4 microg/ml for 7% of S. pneumoniae and 3.5% of S. pyogenes isolates. Ciprofloxacin resistance (MIC, >or=4 microg/ml) was significantly (P < 0.05) associated with macrolide resistance in both S. pyogenes and S. pneumoniae and with penicillin nonsusceptibility in S. pneumoniae.

Antimicrobial susceptibilities of 1,730 Haemophilus influenzae respiratory tract isolates in Spain in 1998-1999.

A beta-lactamase prevalence of 23% was found among 1,730 Haemophilus influenzae isolates. Ampicillin susceptibility was 70%, and 12% of beta-lactamase-negative strains presented diminished susceptibility to ampicillin (BLNAR phenotype). Susceptibility of 90% was found for cefaclor and clarithromycin, whereas it was nearly 100% for cefotaxime, cefixime, azithromycin, and cefuroxime. Ciprofloxacin-resistant (0.1%) and beta-lactamase-positive amoxicillin/clavulanate-resistant (BLPACR) phenotypes (0.1%) are anecdotal so far.

Acinetobacter bacteraemia in a teaching hospital, 1989-1998.

Background: The mortality rate from bacteraemia is one of the highest among infections in hospitals, especially in the intensive care unit (ICU). Recently, an increase in nosocomial bacteraemia caused by gram-negative resistant pathogens has been observed. In this work we review the clinical and laboratory findings of adult patients with Acinetobacter bacteraemia in order to identify risk factors associated with mortality. Methods: A retrospective review of the medical records of patients with Acinetobacter bacteraemia identified by blood cultures from the Diagnostic Microbiology Laboratory was conducted between January 1989 and March 1998. Results: We identified 59 cases of Acinetobacter bacteraemia. Most of the infections (71%) were nosocomial; the majority occurred in the Department of Internal Medicine (28.8%), followed by Haematology (27%) and the ICU (23%). A. lwoffii was isolated in 52.5% of cases and A. baumannii in 47.5%. The related mortality was 17%. Staying in the ICU was associated with A. baumannii bacteraemia (P<0.004). An intravascular catheter was the leading source of infection (37%). Main risk factors were mechanical ventilation (28%), parenteral nutrition (23%) and the presence of a urinary catheter (22%). In the multivariate analysis the independent prognostic factors for mortality were the presence of shock (P<0.05) and the severity of the underlying disease, according to the classification of McCabe (P<0.05). Conclusions: The incidence of Acinetobacter bacteraemia has increased in the last decade, mainly since 1995. The development of septic shock and the severity of the underlying disease appear to be associated with an increase in mortality.

Prognostic factors for pneumococcal bacteremia in a university hospital.

The records of adult patients with pneumococcal bacteremia who were seen over an 8-year-period at an 1,100-bed university teaching hospital were reviewed in order to revise the clinical and laboratory findings and to identify the risk factors associated with mortality. A total of 156 patients were studied, 101 men and 55 women. The mean age of the patients was 65 years. Eighty-seven percent of the patients had community-acquired bacteremia and 13% had nosocomial pneumococcal bacteremia. The overall mortality was 33.9% and the related mortality was 20.5%. The following factors were associated with an increased risk of adverse outcome in the univariate analysis: mechanical ventilation (risk ratio [RR]=3.40; 95% confidence interval [95% CI]=1.44-8.05), administration of parenteral nutrition (RR=3.40; 95% CI =1.44-8.05), and the presence of an intravenous catheter (RR=2.33; 95% CI=1.27-4.24). In the multivariate analysis, the independent prognostic factors for mortality were as follows: development of clinical complications during the episode of bacteremia, rapidly fatal illness, advanced age and administration of parenteral nutrition. The results suggest that the overall mortality due to pneumococcal bacteremia continues to be high. Four independent risk factors associated with increased mortality were identified. Prevention and immunization with polyvalent pneumococcal polysaccharide vaccine should be practiced more widely.

Epidemiological differences between sepsis syndrome with bacteremia and culture-negative sepsis.

OBJECTIVE: To explore the association of putative disease markers and potential risk factors with the nosocomial sepsis syndrome. DESIGN: Prospective case-control study matched for gender, age, and length of preinfection hospital stay. SETTING: 1,200-bed tertiary-care center in Spain. PATIENTS: Cases were selected using the sepsis syndrome criteria of the American College of Chest Physicians/Society of Critical Care Medicine Consensus Conference and were divided into three groups: sepsis with bacteremia (109 cases), sepsis with positive culture other than blood (122 cases), and sepsis with negative culture (115 cases without documented infection but with sepsis syndrome, clinically suspected infection, and empirical antibiotic treatment). Controls were randomly selected from the daily list of inpatients. Data were collected prospectively. Crude and multiple-risk-factor-adjusted odds ratios and their 95% confidence intervals were computed using conditional logistic regression analysis. RESULTS: Presence of coma in the 48 hours before sepsis, intensive care unit (ICU) stay, and decreased serum albumin levels at admission were common epidemiological markers identified for the three groups of cases. Having a central venous catheter was the main healthcare-related risk factor for bacteremia. ICU stay and nasogastric tube were the main risk factors for sepsis with positive culture other than blood. Coma within 48 hours before sepsis and the need of intensive care were the only two markers identified for culture-negative sepsis. CONCLUSION: Culture-negative sepsis does not behave like culture-positive sepsis, and this may imply that implementation of preventive measures to decrease the risk of bacteremia may not decrease the risk of sepsis syndrome.

Analysis of risk factors for nosocomial sepsis in surgical patients.

BACKGROUND: This study aimed to identify patients at high risk for developing sepsis following surgery according to criteria determined by the American College of Chest Physicians and the Society of Critical Care Medicine Consensus Conference on sepsis. METHODS: A prospective case-control study was performed in surgical patients in a tertiary care centre over 1 year. Patients were identified by a daily prospective surveillance. Controls were selected randomly from the daily list of surgical inpatients. Data were collected prospectively. Crude and adjusted odds ratios (ORs) and their 95 per cent confidence intervals were computed using logistic regression analysis. RESULTS: During follow-up, 99 cases and 99 controls were identified. The main risk factors for sepsis found in the multivariate analysis were coma within 48 h before sepsis (OR 13.5, 95 per cent confidence interval 3.6-50.8), low serum albumin level at admission (OR 15.8, 5.4-46.4), two or more intrinsic co-morbidities (OR 11.8, 2.8-49.4) and parenteral nutrition (OR 5.1, 1.5-17.1). Emergency surgery (OR 3.0, 1.4-6.4), abdominal surgery (OR 2.6, 1.0-6.8) and number of surgical interventions (OR 2.5, 1. 1-6.1) were the variables related to surgery that significantly increased the risk of sepsis. Both the study on the Efficacy of Nosocomial Infection Control (SENIC) and the National Nosocomial Infections Surveillance indices showed a statistically significant trend with sepsis. CONCLUSION: Patient-related factors appear to represent the greatest risk for developing postoperative nosocomial sepsis, rather than factors associated with the surgery.

Transient fungaemia due to Candida pelliculosa in a patient with AIDS.

Candida pelliculosa Redaelli (syn. Hansenula anomala) was isolated from blood cultures of a patient with acquired immunodeficiency syndrome. The transient candidaemia was apparently associated with intravenous drug addiction. The isolate was identified by standard methods such as API 20 C Aux and 16 discs carbon auxanogram. The isolate was sensitive to amphotericin B, 5-fluorocytosine and ketoconazole. This organism adds to the growing list of Candida species associated with acquired immunodeficiency syndrome.