Miguel Gallego

PIRO score for community-acquired pneumonia: a new prediction rule for assessment of severity in intensive care unit patients with community-acquired pneumonia.

Objective:To develop a severity assessment tool to predict mortality in community-acquired pneumonia (CAP) patients in intensive care unit (ICU), comparing its performance with Acute Physiology and Chronic Health Evaluation (APACHE) II score and American Thoracic Society/Infectious Disease Society of America (ATS/IDSA) criteria as a prognostic index in CAP patients requiring ICU admission. Design:Secondary analysis of prospective observational cohort study. Setting:Thirty-three ICUs. Patients:Five hundred and twenty-nine adult patients with CAP requiring ICU admission. Measurements and Main Results:A severity assessment score was developed based on the PIRO (predisposition, insult, response, and organ dysfunction) concept including the presence of the following variables: Comorbidities (chronic obstructive pulmonary disease, immunocompromise); age >70 years; multilobar opacities in chest radiograph; shock, severe hypoxemia; acute renal failure; bacteremia and acute respiratory distress syndrome. PIRO score was obtained at ICU within 24 hours from admission, and one point was given for each present feature (range, 0–8 points). The mean PIRO score was significantly higher in nonsurvivors than in survivors (4.6 ± 1.2 vs. 2.3 ± 1.4). Considering the observed mortality for each PIRO score, the patients were stratified in four levels of risk: a) Low, 0–2 points; b) Mild, 3 points; c) high, 4 points; and d) Very high, 5–8 points. Mild-risk (hazard ratio [HR] 1.8; 95% confidence interval [CI] 1.1–2.9; p < 0.05), high-risk (HR 3.1; 95% CI = 2.0–4.7; p < 0.001), and very high risk levels (HR 6.3; 95% CI = 4.2–9.4; p < 0.001) were significantly associated with higher risk of death in Cox proportional hazards regression analysis. Furthermore, analysis of variance showed that higher levels of PIRO score were significantly associated with higher mortality (p < 0.001), prolonged length of stay in the ICU (p < 0.001), and days of mechanical ventilation (p < 0.001). Receiver operating characteristic curves showed that PIRO score (area under the curve [AUC] = 0.88) performed better than APACHE II (AUC = 0.75, p < 0.001) and ATS/IDSA criteria (AUC = 0.80, p < 0.001) to predict 28-day mortality. Conclusions:The PIRO score performed well as 28-day mortality prediction tool in CAP patients requiring ICU admission with a better performance than APACHE II and ATS/IDSA criteria in this subset of patients. Furthermore, PIRO score also is associated with increased healthcare resource utilization in CAP patients admitted in the ICU.

Why Mortality Is Increased in Health-Care-Associated Pneumonia: Lessons From Pneumococcal Bacteremic Pneumonia

BACKGROUND A cohort of patients with bacteremic Streptococcus pneumoniae pneumonia was reviewed to assess why mortality is higher in health-care-associated pneumonia (HCAP) than in community-acquired pneumonia (CAP). METHODS A prospective cohort of all adult patients with bacteremic pneumococcal pneumonia attended at the ED was used. RESULTS One hundred eighty-four cases were classified as CAP and 44 (19%) as HCAP. Fifty-two (23%) were admitted to the ICU. Three (1.5%) isolates were resistant to beta-lactams, and only two patients received inappropriate therapy. The CAP cohort was significantly younger (median age 68 years, interquartile range [IQR] 42-78 vs 77 years, IQR 67-82, P < .001). The HCAP cohort presented a higher Charlson index (2.81 +/- 1.9 vs 1.23 +/- 1.42, P < .001) and had higher severity of illness at admission (altered mental status, respiratory rate > 30/min, Pao(2)/Fio(2) < 250, and multilobar involvement). HCAP patients had a lower rate of ICU admission (11.3% vs 25.5%, P < .05), and a trend toward lower mechanical ventilation (9% vs 19%, P = .17) and vasopressor use (9% vs 18.4%, P = .17) were documented. More patients in the HCAP cohort presented with a pneumonia severity index score > 90 (class IV-V, 95% vs 65%, P < .001), and 30-day mortality was significantly higher (29.5% vs 7.6%, P < .001). A multivariable regression logistic analysis adjusting for underlying conditions and variables related to severity of illness confirmed that HCAP is an independent variable associated with increased mortality (odds ratio = 5.56; 95% CI, 1.86-16.5). CONCLUSIONS Pneumococcal HCAP presents excess mortality, which is independent of bacterial susceptibility. Differences in outcomes were probably due to differences in age, comorbidities, and criteria for ICU admission rather than to therapeutic decisions.

Severity-Related Changes of Bronchial Microbiome in Chronic Obstructive Pulmonary Disease

ABSTRACT Bronchial colonization by potentially pathogenic microorganisms (PPMs) is often demonstrated in chronic obstructive pulmonary disease (COPD), but culture-based techniques identify only a portion of the bacteria in mucosal surfaces. The aim of the study was to determine changes in the bronchial microbiome of COPD associated with the severity of the disease. The bronchial microbiome of COPD patients was analyzed by 16S rRNA gene amplification and pyrosequencing in sputum samples obtained during stable disease. Seventeen COPD patients were studied (forced expiratory volume in the first second expressed as a percentage of the forced vital capacity [FEV1%] median, 35.0%; interquartile range [IQR], 31.5 to 52.0), providing a mean of 4,493 (standard deviation [SD], 2,598) sequences corresponding to 47 operational taxonomic units (OTUs) (SD, 17) at a 97% identity level. Patients were dichotomized according to their lung function as moderate to severe when their FEV1% values were over the median and as advanced when FEV1% values were lower. The most prevalent phyla in sputum were Proteobacteria (44%) and Firmicutes (16%), followed by Actinobacteria (13%). A greater microbial diversity was found in patients with moderate-to-severe disease, and alpha diversity showed a statistically significant decrease in patients with advanced disease when assessed by Shannon (ρ = 0.528; P = 0.029, Spearman correlation coefficient) and Chao1 (ρ = 0.53; P = 0.028, Spearman correlation coefficient) alpha-diversity indexes. The higher severity that characterizes advanced COPD is paralleled by a decrease in the diversity of the bronchial microbiome, with a loss of part of the resident flora that is replaced by a more restricted microbiota that includes PPMs.

Functional Metagenomics of the Bronchial Microbiome in COPD

The course of chronic obstructive pulmonary disease (COPD) is frequently aggravated by exacerbations, and changes in the composition and activity of the microbiome may be implicated in their appearance. The aim of this study was to analyse the composition and the gene content of the microbial community in bronchial secretions of COPD patients in both stability and exacerbation. Taxonomic data were obtained by 16S rRNA gene amplification and pyrosequencing, and metabolic information through shotgun metagenomics, using the Metagenomics RAST server (MG-RAST), and the PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) programme, which predict metagenomes from 16S data. Eight severe COPD patients provided good quality sputum samples, and no significant differences in the relative abundance of any phyla and genera were found between stability and exacerbation. Bacterial biodiversity (Chao1 and Shannon indexes) did not show statistical differences and beta-diversity analysis (Bray-Curtis dissimilarity index) showed a similar microbial composition in the two clinical situations. Four functional categories showed statistically significant differences with MG-RAST at KEGG level 2: in exacerbation, Cell growth and Death and Transport and Catabolism decreased in abundance [1.6 (0.2–2.3) vs 3.6 (3.3–6.9), p = 0.012; and 1.8 (0–3.3) vs 3.6 (1.8–5.1), p = 0.025 respectively], while Cancer and Carbohydrate Metabolism increased [0.8 (0–1.5) vs 0 (0–0.5), p = 0.043; and 7 (6.4–9) vs 5.9 (6.3–6.1), p = 0.012 respectively]. In conclusion, the bronchial microbiome as a whole is not significantly modified when exacerbation symptoms appear in severe COPD patients, but its functional metabolic capabilities show significant changes in several pathways.

Determinants of false-negative results in non-small-cell lung cancer staging by endobronchial ultrasound-guided needle aspiration

OBJECTIVES False-negative results of endobronchial ultrasound-guided transbronchial needle aspiration in non-small-cell lung cancer staging have shown significant variability in previous studies. The aim of this study was to identify procedure- and tumour-related determinants of endobronchial ultrasound-guided transbronchial needle aspiration false-negative results. METHODS We conducted a prospective study that included non-small-cell lung cancer patients staged as N0/N1 by endobronchial ultrasound-guided transbronchial needle aspiration and undergoing therapeutic surgery. The frequency of false-negative results in the mediastinum was calculated. Procedure-related, first, and tumour-related, second, determinants of false-negative results in stations reachable and non-reachable by endobronchial ultrasound were determined by multivariate logistic regression. RESULTS False-negative endobronchial ultrasound-guided transbronchial needle aspiration results were identified in 23 of 165 enrolled patients (13.9%), mainly in stations reachable by endobronchial ultrasound (17 cases, 10.3%). False-negative results were related to the extensiveness of endobronchial ultrasound sampling: their prevalence was low (2.4%) when sampling of three mediastinal stations was satisfactory, but rose above 10% when this requirement was not fulfilled (P = 0.043). In the multivariate analysis, abnormal mediastinum on computer tomography/positron emission tomography [odds ratio (OR) 7.77, 95% confidence interval (CI) 2.19-27.51, P = 0.001] and extensiveness of satisfactory sampling of mediastinal stations (OR 0.37, 95% CI 0.16-0.89, P = 0.026) were statistically significant risk factors for false-negative results in stations reachable by endobronchial ultrasound. False-negative results in non-reachable nodes were associated with a left-sided location of the tumour (OR 10.11, 95% CI 1.17-87.52, P = 0.036). CONCLUSIONS The presence of false-negative ultrasound-guided transbronchial needle aspiration results were observed in nearly 15% of non-small-cell lung cancer patients but in only 3% when satisfactory samples were obtained from three mediastinal stations. False-negative results in stations reachable by endobronchial ultrasound were associated with the extensiveness of sampling, and in stations out of reach of endobronchial ultrasound with left-sided tumours. These results suggest that satisfactory sampling of at least three mediastinal stations by EBUS-TBNA may be a quality criterion to be recommended for EBUS-TBNA staging.

Diagnosis of ventilator-associated pneumonia

Ventilator-associated pneumonia is dif®cult to diagnose and remains a source of considerable controversy despite the recommendations of a consensus conference suggesting bronchoscopic techniques to determine true aetiology. Wet mounts and Gram-stains of sterile ̄uids and urine are examined as a common practice in most hospitals to guarantee the quality of the samples. However, only a few authors have emphasised the relevance of screening respiratory samples ± a simple and economic means of evaluating the quality of samples and an indicator for the initiation of antibiotic treatment. The aim of this review is to demonstrate that decisions regarding empirical therapy can be improved if based on direct examination of the samples and appropriate interpretation of the culture results. # 2001 Lippincott Williams & Wilkins