Time to Clinical Stability in Patients with Ventilator-Associated Pneumonia due to Methicillin-Resistant Staphylococcus aureus Treated with Linezolid versus Vancomycin: Results from the IMPACT-HAP Study

Background: Time to clinical stability is a well-defined early clinical outcome in hospitalized patients with community-acquired pneumonia, but it has not been evaluated in patients with ventilator-associated pneumonia (VAP). The objective of this study was to compare time to clinical stability in patients with MRSA VAP treated with linezolid versus vancomycin. Methods: This was a secondary analysis of the IMPACT-HAP study database. VAP was defined according to CDC criteria. MRSA VAP was considered when MRSA was isolated from a tracheal aspirate or bronchoalveolar lavage. A patient was considered to reach clinical stability the day that the following four criteria were met: 1) Afebrile for 24 hours, 2) Decrease in WBC \u3e10% or WBC within normal range, 3) Improving of PaO2/FiO2 ratio of \u3e 20%, or PaO2/FiO2 ratio \u3e 250, or extubation, or FiO2 ≤ 30% if extubated, and 4) Systolic blood pressure \u3e90 mmHg. Time to clinical stability for linezolid and vancomycin were compared using the Chi-Squared and Student’s t-tests. Results: A total of 89 patients treated with linezolid and 75 patients treated with vancomycin met study criteria. From the population of linezolid treated patients, 79% reached clinical stability, compared to 75% of the population of vancomycin treated patients (P=0.463). Median time to clinical stability was 6 days (IQR 8) for patients treated with linezolid, versus 7 days (IQR 12) for patients treated with vancomycin (P=0.490). Conclusions: This study failed to demonstrate a statistically significant difference in time to clinical stability in patients with MRSA VAP treated with linezolid or vancomycin. The number of days for patients to reach clinical stability can be used as an early clinical outcome in patients with VAP

Sepsis in Patients with Ventilator Associated Pneumonia due to Methicillin- Resistant Staphylococcus aureus: Incidence and Impact on Clinical outcomes

Background: Sepsis is a clinical syndrome associated with organ dysfunction due to a dysregulated host response to infection. Methicillin-resistant Staphylococcus aureus (MRSA) Ventilator-associated pneumonia (VAP) is a serious infection frequently associated with sepsis. The objectives of this study were to define the incidence of sepsis and clinical failure in patients with MRSA VAP. Methods: This was a secondary analysis of the Improving Medicine through Pathway Assessment of Critical Therapy in Hospital-Acquired Pneumonia (IMPACT-HAP) study database. VAP was defined according to CDC criteria. MRSA VAP was considered when MRSA was isolated from a tracheal aspirate or bronchoalveolar lavage. We used the 3rd International Consensus Definitions for sepsis. The presence of clinical failure was evaluated at the 14-day follow-up and defined as: 1) progression of baseline signs and symptoms of pneumonia, or 2) death. The Chi- Square Trend Test was utilized to determine the association between the level of organ dysfunction and clinical failure. Results: MRSA VAP was diagnosed in 205 patients with 138 (67%) presenting with sepsis. Clinical failure occurred in 14% (8/57) of patients without sepsis. Clinical failure occurred in 18% (13/73) of patients with sepsis and 1 organ dysfunction, in 28% (12/43) of patients with sepsis and 2 organ dysfunction, in 28% (5/18) of patients with sepsis and 3 organ dysfunction, and in 100% (4/4) of patients with sepsis and 4 organ dysfunction (p= 0.01). Conclusions: Sepsis is a frequent complication of MRSA VAP and the number of organ dysfunction correlates with clinical failure in these patients. Effective prevention and treatment of sepsis and associated organ dysfunction is essential to avoid cumulative burden of disease in MRSA VAP

Rationale and Methods of the Study Protocol: Streptococcus pneumoniae Serotypes in Adults 18 Years and Older with Radiographically-Confirmed Community-Acquired Pneumonia (CAP)

This study was an active, prospective surveillance study of adults 18 years and older hospitalized with community-acquired pneumonia (CAP) due to Streptococcus pneumoniae conducted at 21 hospitals in ten cities across the United States. This report describes the surveillance methodology applied between October 7, 2013 and September 30, 2016, including the identification and description of surveillance areas and populations at-risk for CAP hospitalization for estimation of incidence rates for selected study sites

Pneumococcal epidemiology among us adults hospitalized for community-acquired pneumonia

BACKGROUND: Few studies have measured the burden of adult pneumococcal disease after the introduction of 13-valent pneumococcal conjugate vaccine (PCV13) into the US infant vaccination schedule. Further, most data regarding pneumococcal serotypes are derived from invasive pneumococcal disease (IPD), which represents only a fraction of all adult pneumococcal disease burden. Understanding which pneumococcal serotypes cause pneumonia in adults is critical for informing current immunization policy. The objective of this study was to measure the proportion of radiographically-confirmed (CXR+) community-acquired pneumonia (CAP) caused by PCV13 serotypes in hospitalized US adults. METHODS: This observational, prospective surveillance study recruited hospitalized adults aged \u3e /=18years from 21 acute care hospitals across 10 geographically-dispersed cities in the United States between October 2013 and September 2016. Clinical and demographic data were collected during hospitalization. Vital status was ascertained 30days after enrollment. Pneumococcal serotypes were detected via culture from the respiratory tract and normally-sterile sites (including blood and pleural fluid). Additionally, a novel, Luminex-based serotype-specific urinary antigen detection (UAD) assay was used to detect serotypes included in PCV13. RESULTS: Of 15,572 enrolled participants, 12,055 eligible patients with CXR+CAP were included in the final analysis population. Mean age was 64.1years and 52.7% were aged \u3e /=65years. Common comorbidities included chronic obstructive pulmonary disease (43.0%) and diabetes mellitus (28.6%). PCV13 serotypes were detected in 552/12,055 (4.6%) of all patients and 265/6347 (4.2%) of those aged \u3e /=65years. Among patients aged 18-64years PCV13 serotypes were detected in 3.8-5.3% of patients depending on their risk status. CONCLUSIONS: After implementation of a pneumococcal conjugate vaccination program in US children, and despite the herd protection observed in US adults, a persistent burden of PCV13-type CAP remains in this population

Absence of Gender-Based Differences in Outcome of Patients with Hospital-Acquired Pneumonia

Background: The objective of this analysis was to evaluate the association between gender and clinical outcomes in intensive care unit (ICU) patients with hospital-acquired pneumonia (HAP) since data thus far are controversial. Methods: Data from a convenience sample of ICU patients with HAP, including ventilator-associated and health care–associated pneumonia, were retrospectively collected from four academic institutions (Improving Medicine through Pathway Assessment of Critical Therapy in Hospital-Acquired Pneumonia [IMPACT-HAP] study). Outcomes included 28-day mortality, clinical failure at day 14, hospital and ICU length of stay (LOS), and duration of mechanical ventilation. We compared baseline characteristics and performed multivariate analysis to identify factors independently associated with mortality. Results: Among 416 patients, 271 were men and 145 were women. Women were older (62.4±16.9 vs. 55.7±16.5 years, p <0.001) and more critically ill, with Acute Physiology and Chronic Health Evaluation (APACHE) II scores of 21 vs. 19 ( p =0.004). Day-28 mortality was 30% for women and 24% for men ( p =0.25). Increased 28-day mortality was associated with severity of illness, age, ventilator-associated pneumonia, vascular disease, and hospital LOS prior to pneumonia diagnosis. No significant differences were found in the distribution of bacteria pathogens or in clinical failure rates (36% vs. 31%) between genders. Duration in days of mechanical ventilation, ICU LOS and hospital LOS after the diagnosis of pneumonia were not significantly different between men and women. Analyzing data for women based on presumed pre- or postmenopausal status (age breakpoint of 50 years), showed an increased in ICU LOS (15 vs. 25 days; p =0.0026) and hospital LOS (22 vs. 30 days; p =0.05) for women ≤50 years. No differences were noted in 28-day mortality (24.3% vs. 13.1%; p =0.18) in women ≤50 years of age. Conclusions: In ICU patients with pneumonia, female gender was not associated with worse outcomes or increased resource utilization compared to male gender. Further studies are needed to evaluate menopausal status and outcomes in women with pneumonia

Incidence of Nephrotoxicity and Association With Vancomycin Use in Intensive Care Unit Patients With Pneumonia: Retrospective Analysis of the IMPACT-HAP Database

The 2005 guidelines from the American Thoracic Society and the Infectious Diseases Society of America recommend vancomycin trough levels of 15 to 20 mg/L for the therapy of hospital-acquired (HAP), ventilator-associated (VAP), and health care–associated (HCAP) pneumonia. The goal of this article was to report the incidence of nephrotoxicity and associated risk factors in intensive care unit patients who received vancomycin for the treatment of HAP, VAP, and HCAP. This was a retrospective analysis of data from a multicenter, observational study of pneumonia patients. Antibiotic-associated nephrotoxicity was defined as either an increase in serum creatinine ≥0.5 mg/dL or 50% above baseline, from initiation of vancomycin to 72 hours after completion of therapy. Univariate and multivariate logistic regression analyses were performed to identify risk factors for development of renal dysfunction. Of the 449 patients in the database, 240 received at least one dose of vancomycin and 188 had sufficient data for analysis. In these 188 patients, 63% were male. Mean (SD) age was 58.5 (17.2) years, and the mean Acute Physiology and Chronic Health Evaluation II score was 19.4 (6.4). Nephrotoxicity occurred in 29 of 188 (15.4%) vancomycin-treated patients. In multivariate analysis, initial vancomycin trough levels ≥15 mg/L (odds ratio [OR], 5.2 [95% CI, 1.9–13.9]; P = 0.001), concomitant aminoglycoside use (OR, 2.67 [95% CI, 1.09–6.54]; P = 0.03), and duration of vancomycin therapy (OR for each additional treatment day, 1.12 [95% CI, 1.02–1.23]; P = 0.02) were independently associated with nephrotoxicity. The incidence of nephrotoxicity increased as a function of the initial vancomycin trough level, rising from 7% at a trough 20 mg/L (P = 0.001). The mean time to nephrotoxicity decreased from 8.8 days at vancomycin trough levels 20 mg/L (Kaplan-Meier analysis, P = 0.0003). Nephrotoxicity may be common among intensive care unit patients with pneumonia treated with broad-spectrum antibiotic therapy that includes vancomycin. The finding that an initial vancomycin trough level ≥15 mg/L may be an independent risk factor for nephrotoxicity highlights the need for additional studies to assess current recommendations for vancomycin dosing for ICU patients with pneumonia

Implementation of guidelines for management of possible multidrug-resistant pneumonia in intensive care: an observational, multicentre cohort study

The American Thoracic Society and Infectious Diseases Society of America provide guidelines for management of hospital-acquired, ventilator-associated, and health-care-associated pneumonias, consisting of empirical antibiotic regimens for patients at risk for multidrug-resistant pathogens. We aimed to improve compliance with these guidelines and assess outcomes. We implemented a performance-improvement initiative in four academic medical centres in the USA with protocol-based education and prospective observation of outcomes. Patients were assessed for severity of illness and followed up until death, hospital discharge, or day 28. We included patients in intensive-care units who were at risk for multidrug-resistant pneumonia and were treated empirically. 303 patients at risk for multidrug-resistant pneumonia were treated empirically, and prescribed treatment was guideline compliant in 129 patients and non-compliant in 174 patients. 44 (34%) patients died before 28 days in the compliance group and 35 (20%) died in the non-compliance group. Five patients in the compliance group and seven in the non-compliance group were lost to follow-up after day 14. Kaplan-Meier estimated survival to 28 days was 65% in the compliance group and 79% in the non-compliance group (p=0·0042). This difference persisted after adjustment for severity of illness. Median length of stay and duration of mechanical ventilation did not differ between groups. Compliance failures included non-use of dual treatment for Gram-negative pathogens in 154 patients and absence of meticillin-resistant Staphylococcus aureus coverage in 24 patients. For patients in whom pathogens were subsequently identified, empirical treatment was active in 79 (81%) of 97 of patients receiving compliant therapy compared with 109 (85%) of 128 of patients receiving non-compliant therapy. Because adherence with empirical treatment was associated with increased mortality, we recommend a randomised trial be done before further implementation of these guidelines. Pfizer, US Medical

Higher clinical success in patients with ventilator-associated pneumonia due to methicillin-resistant Staphylococcus aureus treated with linezolid compared with vancomycin: results from the IMPACT-HAP study

INTRODUCTION: Controversy exists regarding optimal treatment for ventilator-associated pneumonia (VAP) due to methicillin-resistant Staphylococcus aureus (MRSA). The primary objective of this study was to compare clinical success of linezolid versus vancomycin for the treatment of patients with MRSA VAP. METHODS: This was a multicenter, retrospective, observational study of patients with VAP (defined according to Centers for Disease Control and Prevention criteria) due to MRSA who were treated with linezolid or vancomycin. MRSA VAP was considered when MRSA was isolated from a tracheal aspirate or bronchoalveolar lavage. Clinical success was evaluated by assessing improvement or resolution of signs and symptoms of VAP by day 14. After matching on confounding factors, logistic regression models were used to determine if an association existed between treatment arm and clinical success. RESULTS: A total of 188 patients were evaluated (101 treated with linezolid and 87 with vancomycin). The mean ± standard deviation Acute Physiology and Chronic Health Evaluation (APACHE) II score was 21 ± 11 for linezolid- and 19 ± 9 for vancomycin-treated patients (P = 0.041). Clinical success occurred in 85% of linezolid-treated patients compared with 69% of vancomycin-treated patients (P = 0.009). After adjusting for confounding factors, linezolid-treated patients were 24% more likely to experience clinical success than vancomycin-treated patients (P = 0.018). CONCLUSIONS: This study adds to the evidence indicating that patients with MRSA VAP who are treated with linezolid are more likely to respond favorably compared with patients treated with vancomycin