Juan F. Fernandez

Comparison of the Bacterial Etiology of Early-Onset and Late-Onset Ventilator-Associated Pneumonia in Subjects Enrolled in 2 Large Clinical Studies

BACKGROUND: Ventilator-associated pneumonia (VAP) is classified as early-onset or late-onset, in part, to identify subjects at risk for infection with resistant pathogens. We assessed differences in the bacterial etiology of early-onset versus late-onset VAP. METHODS: Subjects enrolled in 2004–2006 in 2 clinical studies of doripenem versus imipenem or piperacillin/tazobactam, with a diagnosis of VAP (n = 500) were included in the analysis. Subjects were classified by ventilator status: early-onset VAP (< 5 d of ventilation) or late-onset VAP (≥ 5 d of ventilation). Baseline demographics and bacterial etiology were analyzed by VAP status. RESULTS: Late-onset VAP subjects had higher Acute Physiology and Chronic Health Evaluation (APACHE II) scores (mean 16.6 versus 15.5, P = .008). There were no significant differences in Clinical Pulmonary Infection Score, sex, age, or presence of bacteremia between the groups. A total of 496 subjects had a baseline pathogen, and 50% of subjects in each group had ≥ 2 pathogens. With the exception of Staphylococcus aureus, which was common in early-onset VAP, the pathogens (including potentially multidrug-resistant (MDR) pathogens) isolated from early-onset versus late-onset VAP were not significantly different between groups. Acinetobacter baumannii or Pseudomonas aeruginosa with decreased susceptibility to any study drug was observed in early-onset and late-onset VAP subjects. CONCLUSIONS: There were no significant differences in the prevalence of potential MDR pathogens associated with early-onset or late-onset VAP, even in subjects with prior antibiotics. Empiric therapy for early-onset VAP should also include agents likely to be effective for potential MDR pathogens. Further prospective studies should evaluate microbiology trends in subjects with VAP.

Technologic advances in endotracheal tubes for prevention of ventilator-associated pneumonia

Ventilator-associated pneumonia (VAP) is associated with high morbidity, mortality, and costs. Interventions to prevent VAP are a high priority in the care of critically ill patients requiring mechanical ventilation (MV). Multiple interventions are recommended by evidence-based practice guidelines to prevent VAP, but there is a growing interest in those related to the endotracheal tube (ETT) as the main target linked to VAP. Microaspiration and biofilm formation are the two most important mechanisms implicated in the colonization of the tracheal bronchial tree and the development of VAP. Microaspiration occurs when there is distal migration of microorganisms present in the secretions accumulated above the ETT cuff. Biofilm formation has been described as the development of a network of secretions and attached microorganisms that migrate along the ETT cuff polymer and inside the lumen, facilitating the transfer to the sterile bronchial tree. Therefore, our objective was to review the literature related to recent advances in ETT technologies regarding their impact on the control of microaspiration and biofilm formation in patients on MV, and the subsequent impact on VAP.

Lung transplant infection.

Lung transplantation has become an accepted therapeutic procedure for the treatment of end‐stage pulmonary parenchymal and vascular disease. Despite improved survival rates over the decades, lung transplant recipients have lower survival rates than other solid organ transplant recipients. The morbidity and mortality following lung transplantation is largely due to infection‐ and rejection‐related complications. This article will review the common infections that develop in the lung transplant recipient, including the general risk factors for infection in this population, and the most frequent bacterial, viral, fungal and other less frequent opportunistic infections. The epidemiology, diagnosis, prophylaxis, treatment and outcomes for the different microbial pathogens will be reviewed. The effects of infection on lung transplant rejection will also be discussed.

Risk factors and antibiotic therapy in P. aeruginosa community-acquired pneumonia.

Current guidelines recommend empirical treatment against Pseudomonas aeruginosa in community‐acquired pneumonia (CAP) patients with specific risk factors. However, evidence to support these recommendations is limited. We evaluate the risk factors and the impact of antimicrobial therapy in patients hospitalized with CAP due to P. aeruginosa.

Improving the 2007 Infectious Disease Society of America/American Thoracic Society severe community-acquired pneumonia criteria to predict intensive care unit admission

PURPOSE To improve 2007 Infectious Disease Society of America/American Thoracic Society (IDSA/ATS) severity criteria to predict intensive care unit (ICU) admission in patients hospitalized with pneumonia. METHODS A composite score that included the 2007 IDSA/ATS criteria for severe pneumonia and additional significant variables identified by recent publications was tested in patients hospitalized with community-acquired pneumonia. RESULTS Among 787 patients hospitalized with community-acquired pneumonia, 156 (19.8%) required admission to the ICU. We identified one major criterion (arterial pH <7.30), and 4 minor criteria (tachycardia >125 bpm, arterial pH 7.30-7.34, sodium <130 mEq/L and glucose >250 mg/dL) to be associated with ICU admission. Adding arterial pH <7.30 to the 2 2007 IDSA/ATS major criteria increased sensitivity from 61.5% to 71.8% and area under the curve (AUC) from 0.80 to 0.86. Adding in sequence the four minor criteria to the 2007 IDSA/ATS minor criteria, increased sensitivity from 41.7% to 53.8%, and AUC from 0.65 to 0.69. In the new composite score, combining 1 of 3 major criteria with 3 of 12 minor criteria showed a sensitivity of 92.9% and an AUC of 0.88. CONCLUSION The addition of arterial pH <7.30 to the 2007 IDSA/ATS major criteria improves sensitivity and AUC to identify patients who will require ICU care.

Clinical evaluation of the role of ceftaroline in the management of community acquired bacterial pneumonia

Ceftaroline fosamil (ceftaroline) was recently approved for the treatment of community- acquired pneumonia (CAP) and complicated skin infections. This newly developed cephalosporin possesses a broad spectrum of activity against gram-positive and gram-negative bacteria. Most importantly, ceftaroline demonstrates potent in vitro antimicrobial activity against multi-drug resistant Streptococcus pneumoniae and methicillin-resistant strains of Staphylococcus aureus. In two Phase III, double-blinded, randomized, prospective trials (FOCUS 1 and FOCUS 2), ceftaroline was shown to be non-inferior to ceftriaxone for the treatment of CAP in hospitalized patients. Ceftaroline exhibits low resistance rates and a safety profile similar to that of other cephalosporins. In this review, we will evaluate the pharmacological characteristics, safety, antimicrobial properties, and efficacy of ceftaroline and its applications in the treatment of CAP.

Impact of Macrolide Therapy in Patients Hospitalized With Pseudomonas aeruginosa Community-Acquired Pneumonia

BACKGROUND Several studies have described a clinical benefit of macrolides due to their immunomodulatory properties in various respiratory diseases. We aimed to assess the effect of macrolide therapy on mortality in patients hospitalized for Pseudomonas aeruginosa community-acquired pneumonia (CAP). METHODS We performed a retrospective population-based study of > 150 hospitals in the US Veterans Health Administration. Patients were included if they had a diagnosis of CAP and P aeruginosa was identified as the causative pathogen. Patients with health-care-associated pneumonia and immunosuppression were excluded. Macrolide therapy was considered when administered within the first 48 h of admission. Univariate and multivariable analyses were performed using 30-day mortality as the dependent measure. RESULTS We included 402 patients with P aeruginosa CAP, of whom 171 (42.5%) received a macrolide during the first 48 h of admission. These patients were older and white. Macrolide use was not associated with lower 30-day mortality (hazard ratio, 1.14; 95% CI, 0.70-1.83; P = .5). In addition, patients treated with macrolides had no differences in ICU admission, use of mechanical ventilation, use of vasopressors, and length of stay (LOS) compared with patients not treated with macrolides. A subgroup analysis among patients with P aeruginosa CAP in the ICU showed no differences in baseline characteristics and outcomes. CONCLUSIONS Macrolide therapy in the first 48 h of admission is not associated with decreased 30-day mortality, ICU admission, need for mechanical ventilation, and LOS in hospitalized patients with P aeruginosa CAP. Larger cohort studies should address the benefit of macrolides as immunomodulators in patients with P aeruginosa CAP.

Pulmonary Mucormycosis: What Is the Best Strategy for Therapy?

Pulmonary mucormycosis is an uncommon but life-threatening opportunistic fungal infection.[1][1],[2][2] It typically affects immunocompromised patients, such as recipients of stem cell or organ transplant, and has worse outcomes in those with hematologic malignancy or neutropenia.[1][1],[3][3] In

Predicting ICU admission in community-acquired pneumonia: clinical scores and biomarkers

Community-acquired pneumonia (CAP) remains a common and serious worldwide health problem. Despite all the advances in therapy, significant interest has focused on the identification of patients with CAP who require intensive care unit admission to improve their outcomes. The severity assessment of CAP provides an important guide to clinicians in deciding the site of care and the use of empiric antibiotics and adjuvant therapy. For years, several clinical assessment scores have been suggested and validated to achieve this goal. The recent introduction of biomarkers as prognostic indicators of severe CAP, whether used alone or in conjunction with other clinical severity of illness scores, has been investigated. An objective scoring system with a high level of sensitivity and specificity to predict the severity of CAP and the need for high levels of care do not exist. Today, the addition of clinical scores and biomarkers to clinical judgment is the best approach to optimize the care of severe CAP. Future research will allow validation of these and newer tools to improve the prognosis of patients with CAP.

Understanding the Concept of Health Care-Associated Pneumonia in Lung Transplant Recipients.

BACKGROUND Limited data are available regarding the etiologic impact of health care-associated pneumonia (HCAP) in lung transplant recipients. Therefore, our aim was to evaluate the microbiologic differences between HCAP and hospital-acquired pneumonia (HAP)/ventilator-associated pneumonia (VAP) in lung transplant recipients with a radiographically confirmed diagnosis of pneumonia. METHODS We performed a retrospective cohort study of lung transplant recipients with pneumonia at one transplant center over a 7-year period. Eligible patients included lung transplant recipients who developed a first episode of radiographically confirmed pneumonia ≥ 48 h following transplantation. HCAP, HAP, and VAP were classified according to the American Thoracic Society/Infectious Diseases Society of America 2005 guidelines. χ² and Student t tests were used to compare categorical and continuous variables, respectively. RESULTS Sixty-eight lung transplant recipients developed at least one episode of pneumonia. HCAP (n = 42; 62%) was most common, followed by HAP/VAP (n = 26; 38%) stratified in HAP (n = 20; 77%) and VAP (n = 6; 23%). Pseudomonas aeruginosa was the predominantly isolated organism (n = 22; 32%), whereas invasive aspergillosis was uncommon (< 10%). Multiple-drug resistant (MDR) pathogens were less frequently isolated in patients with HCAP compared with HAP/VAP (5% vs 27%; P = .009). Opportunistic pathogens were less frequently identified in lung transplant recipients with HCAP than in those with HAP/VAP (7% vs 27%; P = .02). Lung transplant recipients with HCAP had a similar mortality at 90 days (n = 9 [21%] vs n = 4 [15%]; P = .3) compared with patients with HAP/VAP. CONCLUSIONS HCAP was the most frequent infection in lung transplant recipients. MDR pathogens and opportunistic pathogens were more frequently isolated in HAP/VAP. There were no differences in 30- and 90-day mortality between lung transplant recipients with HCAP and those with HAP/VAP.