Moving beyond unsolicited consultation: additional impact of a structured intervention on mortality in Staphylococcus aureus bacteraemia.

BACKGROUND: Some evidence-based bundles have tried to standardize the management of Staphylococcus aureus bacteraemia (SAB) to improve the outcome. The aim of our study was to analyse the additional impact on mortality of a structured intervention in patients with SAB. METHODS: Compliance with the bundle was evaluated in an ambispective cohort of patients with SAB, which included a retrospective cohort [including patients treated before and after the implementation of a bacteraemia programme (no-BP and BP, respectively)] and a prospective cohort (i-BP), in which an additional specific intervention for bundle application was implemented. Multivariate logistic regression was used to measure the influence of the independent variables including compliance with the bundle on 14 and 30 day crude mortality. RESULTS: A total of 271 adult patients with SAB were included. Mortality was significantly different among the three groups (no-BP, BP and i-BP): mortality at 14 days was 18% versus 7% versus 2%, respectively, P = 0.002; and mortality at 30 days was 20% versus 12% versus 5%, respectively, P = 0.011. The factors associated with 14 and 30 day mortality in multivariable analysis were heart failure (OR = 7.63 and OR = 2.27, respectively), MRSA infection (OR = 4.02 and OR = 4.37, respectively) and persistent bacteraemia (OR = 11.01 and OR = 7.83, respectively); protective factors were catheter-related bacteraemia (OR = 0.16 and OR = 0.19, respectively) and >75% bundle compliance (OR = 0.15 and OR = 0.199, respectively). Time required to perform the intervention and the follow-up was 50 min (IQR 40-55 min) per patient. CONCLUSIONS: High-level compliance with a standardized bundle of intervention for management of SAB that requires little time was associated with lower mortality at 14 and 30 days.

Short- versus long-course therapy in gram-negative bacilli bloodstream infections.

Bacteremia due to gram-negative bacilli (GNB) is one of the most frequent causes of admission and prolongation of hospital stay. Nevertheless, optimal duration of antibiotic treatment is not clearly established. We designed an observational, prospective study of a cohort of adult patients with uncomplicated GNB bacteremia. They were classified according to the duration of treatment in short (7-10 days) or long (> 10 days) course. Mortality and bacteremia recurrence rate were evaluated, and propensity score for receiving short-course treatment was calculated. A total of 395 patients met eligibility criteria including 232 and 163 who received long- and short-course therapy, respectively. Median age was 71 years, 215 (54.4% male) and 51% had a urinary source. Thirty-day mortality was 12%. In multivariate analysis by logistic regression stratified according to propensity score quartile for receiving short-course therapy showed no association of duration of treatment with 30-day mortality or 90-day recurrence rate. Based on the results observed in our cohort, short-course therapy could be as safe and effective as longer courses.

Validation of a clinical decision tree to predict if a patient has a bacteraemia due to a ß-lactamase producing organism.

BACKGROUND: In recent years, several scores and algorithms have been developed in order to guide empirical antibiotic treatment in patients with gram-negative bacilli (GNB) bacteraemia according to the risk of extended-spectrum ß-lactamase (BL) producing. Some of these algorithms do not have easy applicability or present some limitations in their validation. The aim of our study was to validate a recently designed decision tree in our prospective cohort of bacteraemia due to gram-negative bacilli. METHODS: We prospectively identified and analyzed all bacteraemia due to gram-negative bacilli in adult patients in our centre between January 2015 and December 2016. Previously developed clinical decision tree was used to classify patients in each of the terminal nodes. Patients were classified as BL group according to whether they were producers of any type of BL. The statistical power of the tree was analyzed by receiver operating characteristics (ROC) curve and by calculation of C-statistics. RESULTS: A total of 448 episodes of bacteraemia were included; 132 (29.5%) were BL group; 68 (15.1%) ESBL producing, 43 (9.6%) due to AmpC and 21 (4.7%) isolates of Pseudomonas aeruginosa. The original clinical decision tree was modified according to the results of our multivariate analysis. The modified tree has a sensitivity of 71%, specificity of 92%, predictive positive value (PPV) of 79% and predictive negative value (NPV) of 88% generating an ROC curve with a C-statistic of 0.76. CONCLUSIONS: An easy-to-apply clinical decision tree could be used at the exact moment of diagnosis and adjust the empirical antibiotic treatment in patients with gram-negative bacilli bacteraemia.