Pneumonia Severity Index Class Research Articles

Efficacy of Corticosteroids in Community-acquired Pneumonia

Some studies have shown a beneficial effect of corticosteroids in patients with community-acquired pneumonia (CAP), possibly by diminishing local and systemic antiinflammatory host response. To assess the efficacy of adjunctive prednisolone treatment in patients hospitalized with CAP. Hospitalized patients, clinically and radiologically diagnosed with CAP using standard clinical and radiological criteria, were randomized to receive 40 mg prednisolone for 7 days or placebo, along with antibiotics. Primary outcome was clinical cure at Day 7. Secondary outcomes were clinical cure at Day 30, length of stay, time to clinical stability, defervescence, and C-reactive protein. Disease severity was scored using CURB-65 (a severity index for community-acquired pneumonia evaluating Confusion, blood Urea nitrogen, Respiratory rate, Blood pressure, and age 65 or older) and Pneumonia Severity Index. We enrolled 213 patients. Fifty-four (25.4%) patients had a CURB-65 score greater than 2, and 93 (43.7%) patients were in Pneumonia Severity Index class IV-V. Clinical cure at Days 7 and 30 was 84/104 (80.8%) and 69/104 (66.3%) in the prednisolone group and 93/109 (85.3%) and 84/109 (77.1%) in the placebo group (P = 0.38 and P = 0.08). Patients on prednisolone had faster defervescence and faster decline in serum C-reactive protein levels compared with placebo. Subanalysis of patients with severe pneumonia did not show differences in clinical outcome. Late failure (>72 h after admittance) was more common in the prednisolone group (20 patients, 19.2%) than in the placebo group (10 patients, 6.4%; P = 0.04). Adverse events were few and not different between the two groups. Prednisolone (at 40 mg) once daily for a week does not improve outcome in hospitalized patients with CAP. A benefit in more severely ill patients cannot be excluded. Because of its association with increased late failure and lack of efficacy prednisolone should not be recommended as routine adjunctive treatment in CAP.

Utility of C-reactive protein in assessing the disease severity and complications of community-acquired pneumonia

Previous studies on the usefulness of C-reactive protein (CRP) in patients with community-acquired pneumonia (CAP) have yielded somewhat inconsistent results. Our aim was to assess the value of CRP in estimating the severity and complications of CAP. CRP levels during the first 5 days of hospitalization were measured in 384 adult patients with CAP, and the data were evaluated using comprehensive statistical analyses. Significantly higher CRP levels on admission were detected in Pneumonia Severity Index (PSI) classes III–V than in classes I and II (p <0.001). An increment of 50 mg/L CRP on admission was associated with a 1.22-fold odds for a patient to be in PSI classes III–V as compared with classes I and II (OR 1.22, 95% CI 1.11–1.34; p <0.001). CRP levels were significantly higher in bacteraemic pneumonia than in non-bacteraemic pneumonia (p <0.001). An increment of 50 mg/L CRP was associated with a 1.67-fold odds for a patient to be bacteraemic (OR 1.67, 95% CI 1.46–1.92; p <0.001). CRP levels >100 mg/L on day 4 after the admission were significantly associated with complications (p <0.01). There was a trend for an association between the level of CRP on admission and the time to reach clinical stability (p <0.01). In conclusion, CRP may be valuable for revealing the development of complications in CAP. It may also be useful to assess the disease severity, thus being complementary to the assessment of the PSI. In our patients, high CRP levels were associated with a failure to reach clinical stability.

Clinical response to ertapenem in severe community-acquired pneumonia: a retrospective series in an elderly population

To evaluate in routine hospital practice the clinical response to ertapenem in comparison with other parenteral antibiotics in the treatment of community-acquired pneumonia (CAP), clinical records from patients with severe CAP treated with ertapenem from July 2002 to June 2006 in seven Spanish hospitals were retrospectively reviewed. Patients were classified according to the Pneumonia Severity Index (PSI). Each ertapenem-treated patient was matched with two patients in the same hospital treated with other antibiotics, according to age (difference ≤5 years), same PSI class and whether or not resident in a nursing home. Seventy-one patients treated with ertapenem and 131 matched controls were identified; 71 of the 202 patients came from nursing homes. A larger (p 0.0002) number of patients were treated with monotherapy in the ertapenem group. In total, 174 patients (86.1%) belonged to PSI classes IV–V; a higher (p <0.0001) PSI score was found in patients from nursing homes. The mean age was 80.5 years (75% of patients >76 years). Comorbidities were present in 193 patients (95.5%). No differences were found in median hospital stay (7 days for ertapenem vs. 10 days for comparators, p 0.066). A slightly higher clinical response rate was obtained for ertapenem vs. comparators (88.7% vs. 77.1%; p 0.0465; OR 2.25; 95% CI 0.99–5.12), with significant differences in clinical response in patients coming from nursing homes (95.8% ertapenem vs. 63.8% comparators; p 0.0034) but not in non-institutionalized patients (85.4% ertapenem vs. 84.5% comparators; p 0.929). The higher clinical response to ertapenem vs. comparators in severe CAP was due to its significantly higher efficacy in healthcare-associated CAP in patients coming from nursing homes.

Validation of the Infectious Diseases Society of America/American Thoracic Society criteria to predict severe community-acquired pneumonia caused by Streptococcus pneumoniae

Background Severe community-acquired pneumonia (CAP) is usually defined as pneumonia that requires intensive care unit (ICU) admission; the primary pathogen responsible for ICU admission is Streptococcus pneumoniae. In this study, the 2007 Infectious Diseases Society of America/American Thoracic Society (IDSA/ATS) consensus criteria for ICU admission were compared with other severity scores in predicting ICU admission and mortality. Methods We retrospectively studied 158 patients with pneumococcal CAP (1999-2003). Clinical and laboratory features at the emergency department were recorded and used to calculate the 2007 IDSA/ATS rule, the 2001 ATS rule, 2 modified 2007 IDSA/ATS rules, the Pneumonia Severity Index (PSI), and the CURB (confusion, urea, respiratory rate, blood pressure) score. The sensitivity, specificity, positive predictive value, and negative predictive value (NPV) were assessed for the various indices. We also determined the criteria that were independently predictive of ICU admission and of mortality in our population. Results The 2007 IDSA/ATS criteria performed as well as the 2001 ATS rule in predicting ICU admission both demonstrated high sensitivity (90%) and NPV (97%). For the prediction of mortality, the best tool proved to be the PSI score (sensitivity, 95%; NPV, 99%). The variables associated with ICU admission in this patient population included tachypnea, confusion, Pa o 2/Fi o 2 ratio of 250 or lower, and hypotension requiring fluid resuscitation. Mechanical ventilation and PSI class V were independently associated with mortality. Conclusions This study confirms the usefulness of the new criteria in predicting severe CAP. The 2001 ATS criteria seem an attractive alternative because they are simple and as effective as the 2007 IDSA/ATS criteria.

Midregional Proadrenomedullin as a Prognostic Tool in Community-Acquired Pneumonia

Midregional proadrenomedullin (MR-proADM) is a potential prognostic biomarker in patients with community-acquired pneumonia (CAP). Previous work has been hampered by sample size and illness spectrum limits. We sought to describe the pattern of MR-proADM in a broad CAP cohort, confirm its prognostic role, and compare its performance to procalcitonin, a novel biomarker of infection. We conducted a multicenter prospective cohort study in 28 community and teaching EDs. Patients with a clinical and radiographic diagnosis of CAP were enrolled. We stratified MR-proADM levels a priori into quartiles and quantified severity of illness using the pneumonia severity index (PSI); and confusion (abbreviated mental test score of <or= 8), urea >or= 7 mmol/L, respiratory rate >or= 30 breaths/min, BP < 90 mm Hg systolic or < 60 mm Hg diastolic, age >or= 65 years (CURB-65). The primary outcome was 30-day mortality. A total of 1,653 patients formed the study cohort. MR-proADM levels consistently rose with PSI class and 30-day mortality (p < 0.001). MR-proADM had a higher area under the curve for 30-day mortality than procalcitonin (0.76 vs 0.65, respectively; p < 0.001), but adding MR-proADM to the PSI in all subjects minimally improved performance. Among low-risk subjects (PSI classes I to III), mortality was low and did not differ by MR-proADM quartile. However, among high-risk subjects (PSI class IV/V; n = 546), subjects in the highest MR-proADM quartile (n = 232; 42%) had higher 30-day mortality than those in MR-proADM quartiles 1 to 3 (23% vs 9%, respectively; p < 0.0001). Similar results were seen with CURB-65. MR-proADM and procalcitonin levels were generally concordant; only 6% of PSI class IV/V subjects in the highest MR-proADM quartile had very low procalcitonin levels (< 0.1 ng/mL). In our multicenter CAP cohort, MR-proADM levels correlate with increasing severity of illness and death. High MR-proADM levels offer additional risk stratification in high-risk CAP patients, but otherwise MR-proADM levels do not alter PSI-based risk assessment in most CAP patients.

Severity of Pneumococcal Pneumonia Associated With Genomic Bacterial Load

There is a clinical need for more objective methods of identifying patients at risk for septic shock and poorer outcomes among those with community-acquired pneumonia (CAP). As viral load is useful in viral infections, we hypothesized that bacterial load may be associated with outcomes in patients with pneumococcal pneumonia. Quantification of Streptococcus pneumoniae DNA level by real-time polymerase chain reaction (rt-PCR) was prospectively conducted on whole-blood samples from a cohort of 353 patients who were displaying CAP symptoms upon their admission to the ED. CAP caused by S pneumoniae was documented in 93 patients (36.5% with positive blood culture findings). A positive S pneumoniae rt-PCR assay finding was associated with a statistically significant higher mortality (odds ratio [OR], 7.08), risk for shock (OR, 6.29), and the need for mechanical ventilation (MV) [OR, 7.96]. Logistic regression, adjusted for age, sex, comorbidities, and pneumonia severity index class, revealed bacterial load as independently associated with septic shock (adjusted odds ratio [aOR], 2.42; 95% CI, 1.10 to 5.80) and the need for MV (aOR, 2.71; 95% CI, 1.17 to 6.27). An S pneumoniae bacterial load of >or= 10(3) copies per milliliter occurred in 29.0% of patients (27 of 93 patients; 95% CI, 20.8 to 38.9%) being associated with a statistically significant higher risk for septic shock (OR, 8.00), the need for MV (OR, 10.50), and hospital mortality (OR, 5.43). In patients with pneumococcal pneumonia, bacterial load is associated with the likelihood of death, the risk of septic shock, and the need for MV. High genomic bacterial load for S pneumoniae may be a useful tool for severity assessment.

Is it possible to predict which patients with mild pneumonias will develop hypoxemia?

Usually, mortality due to mild community-acquired pneumonias (CAP) (Pneumonia severity index (PSI) classes I-III) is low (<3%), but the appearance of hypoxemia significantly increases mortality. Our aim was to determine the clinical parameters associated with risk factors of developing hypoxemia in subjects with mild CAP (PSI I-III) and the clinical outcomes of the hypoxemic group. We analyzed clinical characteristics and the outcomes of patients with mild CAP and hypoxemia (PaO2/FiO2<300), in a prospective, multicenter cohort study of 1195 patients. Mild pneumonias (PSI I-III) were found in 645 cases (53.9%), of which 217 (33.6%) presented hypoxemia according to a PaO2/FiO2<300. Patients with PaO2/FiO2<300 required more ICU admissions, mechanical ventilation, and developed septic shock than other PSI I-III patients. The clinical parameters associated with hypoxemia were: COPD, bilateral chest X-ray involvement, and hypoalbuminemia. We conclude that patients with COPD, those with bilateral chest X-ray involvement, or hypoalbuminemia were significantly more likely to have hypoxemia in mild CAP. Hypoxemic patients with low-risk pneumonia have worse clinical outcomes, including more ICU admission, need for mechanical ventilation and presence of septic shock than non-hypoxemic low-risk patients.

Predicting Positive Blood Cultures in Patients presenting with Pneumonia at an Emergency Department in Singapore

Routine blood cultures have been recommended for all patients in treatment guidelines for community-acquired pneumonia (CAP). This practice has become a major area of resource utilisation, despite the lack of evidence in its clinical utility. Calls for abandoning the practice is balanced by the occasions of uncovering an unexpected pathogen or an unusual antimicrobial resistance pattern. The aim of this study is to identify factors that predict positive blood cultures among patients hospitalised for pneumonia upon presentation at the Emergency Department (ED). A case control study was carried out on patients treated for pneumonia in the ED who had routine blood cultures performed as part of their management. The pneumonia severity index (PSI) was used to categorize patients into low- and high-risk for 30-day mortality. Logistic regression was carried out to determine factors significantly associated with positive blood cultures, from which a predictive probability equation was used to identify patients whose blood cultures were negative at a pre-determined cut-off, with minimum number of culture positive misclassification. A scoring system was devised, with scores predicting which patients would be likely to have a positive or negative blood culture. A total of 1407 patients with pneumonia were treated at ED from May to December 2006, from whom 1800 blood cultures were performed. Of these, 140 cultures (7.8%) grew organisms, comprising 96 (5.3%) true positive cultures and 44 (2.4%) contaminated cultures. Logistic regression analysis identified ill patients with higher PSI classes, smokers and Malay patients to be more likely to have positive blood cultures. Patients who had prior treatment with antibiotics, chronic obstructive pulmonary disease and cough were less likely to have positive blood cultures. An index to predict a negative blood culture resulted in the accurate classification of all but 4 positive patients while still correctly classifying 27.8% of blood culture negative patients. The area under the ROC curve was 0.71 (95% CI, 0.65-0.76). A simplified scoring system was devised based on the predictive model had a sensitivity of 82% and specificity of 38.2% for a positive blood culture. Routine blood cultures yielded negative results in 94% of patients presenting with pneumonia. The development of the clinical scoring system is a first step towards selecting patients for whom blood cultures is performed and improve cost-effectiveness.

Prospective Comparison of Severity Scores for Predicting Clinically Relevant Outcomes for Patients Hospitalized With Community-Acquired Pneumonia

The comparative accuracy and discriminatory power of three validated rules for predicting clinically relevant outcomes other than mortality in patients hospitalized with community-acquired pneumonia (CAP) are unknown. We prospectively compared the newly developed severe community-acquired pneumonia (SCAP) score, pneumonia severity index (PSI), and the British Thoracic Society confusion, urea > 7 mmol/L, respiratory rate > or = 30 breaths/min, BP < 90 mm Hg systolic or < 60 mm Hg diastolic, age > or = 65 years (CURB-65) rule in an internal validation cohort of 1,189 consecutive adult inpatients with CAP from one hospital and an external validation cohort of 671 consecutive adult inpatients from three other hospitals. Major adverse outcomes were admission to ICU, need for mechanical ventilation, progression to severe sepsis, or treatment failure. Mean hospital length of stay (LOS) was also evaluated. The rules were compared based on sensitivity, specificity, and area under the curve (AUC) of the receiver operating characteristic. The rate of all adverse outcomes and hospital LOS increased directly with increasing SCAP, PSI, or CURB-65 scores (p < 0.001) in both cohorts. Patients classified as high risk by the SCAP score showed higher rates of adverse outcomes (ICU admission, 35.8%; mechanical ventilation, 16.4%; severe sepsis, 98.5%; treatment failure, 22.4%) than PSI and CURB-65 high-risk classes. The discriminatory power of SCAP, as measured by AUC, was 0.75 for ICU admission, 0.76 for mechanical ventilation, 0.79 for severe sepsis, and 0.61 for treatment failure in the external validation cohort. AUC differences with PSI or CURB-65 were found. The SCAP score is as accurate or better than other current scoring systems in predicting adverse outcomes in patients hospitalized with CAP while helping classify patients into different categories of increasing risk for potentially closer monitoring.

The Influence of COPD on Mortality and Severity Scoring in Community-Acquired Pneumonia

Background: Chronic obstructive lung disease (COPD) is a frequent co-morbidity in patients hospitalised with community-acquired pneumonia (CAP). In recent retrospective studies, higher mortality in patients with CAP and COPD was found. Objectives: The aim of the study was to determine the 30-day mortality and to evaluate the differences in CAP severity scoring in hospitalised patients with COPD. Methods: A subanalysis of a randomized clinical trial was performed. Results: A total of 262 patients with CAP were included. Ninety-five (36.3%) patients had COPD. A total of 28 (10.7%) patients died within 30 days. No differences between patients with and without COPD in 30-day mortality were observed [8 (8.4%) vs. 20 (12.0%), p = 0.37]. In the Pneumonia Severity Index (PSI), significant differences in age, gender and heart rate between patients with and without COPD were observed. Patients with COPD were stratified in higher PSI classes. In the CURB-65 score, age ≥65 years was significantly higher in patients with COPD [72 (75.8%) vs. 88 (52.7%), p = <0.01]. In a multivariate analysis, only the need for intensive care unit admission and high serum glucose were predictors of mortality [OR 32.50 (95% CI 6.87–153.75), p < 0.01; OR 7.34 (95% CI 1.19–45.4), p = 0.03]. Conclusions: Mortality was not increased in patients with COPD hospitalised with CAP. Severity scores are influenced by age and gender. Further studies evaluating CAP in patients with COPD are needed to explain these findings.

Repeated Pneumonia Severity Index Measurement After Admission Increases its Predictive Value for Mortality in Severe Community-acquired Pneumonia

Severe community-acquired pneumonia (CAP) is associated with high hospital mortality, and accurate assessment of patients is important for supporting clinical decision making. The Pneumonia Severity Index (PSI) is a good tool for predicting disease severity, especially in the low-risk group of patients with CAP. We investigated whether the change in PSI measurement after admission could identify patients at high risk of mortality from CAP. We prospectively studied 250 inpatients with CAP. PSI was measured at admission and 72 hours later at a tertiary referral medical center from May 2005 to February 2006. The initial and repeated PSI results were compared. Hospital mortality was used as the outcome measure. Initial PSI in high-risk patients (PSI class > IV) had a low specificity (37%), and a low positive predictive value (PPV) (17%). Increased repeated PSI score, as compared with initial score, was associated with an increased mortality rate (from 7.8% to 33.3% in class IV, and 25.3% to 53.3% in class V; p < 0.0001), and improved the predictive value, with 94% specificity and a PPV of 46% for mortality in high-risk patients. Increased PSI score, 72 hours after admission, for patients with CAP improved the predictive value of PSI score and more accurately identified patients with a high risk of mortality.

Health-Care-Associated Pneumonia

Health-Care-Associated Pneumonia

Factores relacionados con una estancia media hospitalaria prolongada en la neumonía adquirida en la comunidad

The length of hospital stay in patients with community-acquired pneumonia (CAP) varies considerably, even though this factor has a great impact on the cost of care for this condition. The objective of this study was to identify factors associated with prolonged hospitalization in these patients (>8 days). Observational analysis of a prospective cohort of nonimmunosuppressed adults with CAP requiring hospitalization from 1995 through 2006. We documented a total of 2688 consecutive episodes of CAP. Patients who required intensive care unit admission from the emergency room (n=107), those who died during hospitalization (n=200), and patients hospitalized for more than 30 days (n=60) were excluded from the analysis. The median duration of hospital stay was 8 days (IQR, 6-11). Factors independently associated with prolonged hospital stay by stepwise multiple logistic regression analysis were advanced age (OR=1.58; 95% CI, 1.002-2.503), alcohol abuse (OR=2.07; 95% CI, 1.341-3.199), high-risk Pneumonia Severity Index class (OR=1.72; 95% CI, 1.094-2.703), aspiration pneumonia (OR=4.57; 95% CI, 1.085-19.285), pleural empyema (OR=3.73; 95% CI, 1.978-7.04), and time to clinical stability (OR=1.13; 95% CI, 1.065-1.196). Several factors that were independently associated with longer hospital stay in adult patients with CAP. These factors should be considered when evaluating the adequacy of the duration of hospitalization in a specific center and when designing future studies investigating new strategies to reduce the length of hospital stay.

Admission D-dimer Can Identify Low-Risk Patients With Community-Acquired Pneumonia

Severity assessment is an important component of the management of community-acquired pneumonia. Clinicians are increasingly searching for biomarkers to aid in clinical decisions. Coagulation disorders can accompany severe pneumonia. We seek to investigate the association of D-dimer, a fibrinolysis biomarker, and 30-day mortality or the need for mechanical ventilation or vasopressor support in emergency department (ED) patients with community-acquired pneumonia. We prospectively enrolled ED patients with community-acquired pneumonia between December 2005 and January 2008 in a convenience manner. We measured D-dimer level with the Vitek ImmunoDiagnostic Assay System. To assess clinical illness severity, both CURB65 and the Pneumonia Severity Index (Pneumonia Severity Index class) were calculated. Our primary outcomes were 30-day mortality and need for mechanical ventilation or vasopressor support. Of the 314 enrolled patients, 23.9% of patients had a D-dimer level less than 500 ng/mL on initial ED measurement, and 81.3% of these patients were in Pneumonia Severity Index class I to III. A D-dimer level of less than 500 ng/mL had a negative likelihood ratio of 0 (95% confidence interval 0 to 1.37) for 30-day mortality and 0.33 (95% confidence interval 0.09 to 1.27) for need for mechanical ventilation or vasopressor support. For 30-day mortality, the area under the receiver operator characteristic curve for D-dimer was similar to both CURB65 and Pneumonia Severity Index class. For mechanical ventilation or vasopressor support, the area under the receiver operator characteristic curve for D-dimer was lower than that for CURB65 but did not differ from that for Pneumonia Severity Index. An admission D-dimer level less than 500 ng/mL is associated with low risk of short-term death and major morbidity in patients with community-acquired pneumonia.

Potential for Cost-Savings in the Care of Hospitalized Low-Risk Community-Acquired Pneumonia Patients in China

Background The cost of treating community-acquired pneumonia (CAP) in China is a heavy economic burden for the society. Objective To investigate the costs of hospitalization of low-risk CAP patients and how hospitalization costs can be reduced through proper usage of hospital resources. Methods Two hundred thirty-six patients with low-risk CAP who were hospitalized between January 2000 and December 2005 in a 1161-bed tertiary care teaching hospital were included in a retrospective cohort study. Their hospitalization costs and antibiotic therapy were analyzed. General linear model was utilized to determine correlative variables associated with total hospital costs. Results The median length of hospital stay was 12 days and the median duration of intravenous (IV) antibiotic therapy was 10 days, they were correlated significantly ( P = 0.000, r = 0.81). The median total hospital cost was $556.50 (mean $705.60), of which 48.9% was for drugs, 21.9% for laboratory tests, 8.6% for radiology, 6.5% for medical staff, 6.3% for hospital beds, and 5.3% for examination. General linear model analysis determined that duration of IV antibiotic therapy, Pneumonia Severity Index class, age, and initial empirical antibiotic therapy failure were correlative factors of total hospital costs. Pathogens were identified in 106 patients (44.9%), Mycoplasma pneumoniae was the most common pathogen (19.9%), followed by Streptococcus pneumoniae (8.5%), and Haemophilus influenza (5.5%). The majority of patients accepted initial empirical β-lactam (37.3%) or fluoroquinolone (30.9%) monotherapy, the empirical treatment failure rates were 20.5% and 5.5%, respectively. Conclusions Efforts to reduce duration of IV antibiotic therapy will have the most profound effect on reducing total hospital costs of low-risk CAP. The atypical pathogens should be considered for initial empirical antibiotics in low-risk CAP therapy in China.

Long-Term Morbidity and Mortality After Hospitalization With Community-Acquired Pneumonia

Little is known about the long-term sequelae of community-acquired pneumonia (CAP). Therefore, we describe the long-term morbidity and mortality of patients after pneumonia requiring hospitalization. We specifically hypothesized that the Pneumonia Severity Index (PSI), designed to predict 30-day pneumonia-related mortality, would also be associated with longer-term all-cause mortality. Between 2000 and 2002, 3415 adults with CAP admitted to 6 hospitals in Edmonton, Alberta, Canada, were prospectively enrolled in a population-based cohort. At the time of hospital admission, demographic, clinical, and laboratory data were collected and the PSI was calculated for each patient. Postdischarge outcomes through to 2006 were ascertained using multiple linked administrative databases. Outcomes included all-cause mortality, hospital admissions, and re-hospitalization for pneumonia over a maximum of 5.4 years of follow-up. Follow-up data were available for 3284 (96%) patients; 66%were > or =65 years of age, 53% were male, and according to the PSI fully 63% were predicted to have greater than 18% 30-day pneumonia-related mortality (that is, PSI class IV-V). Median follow-up was 3.8 years. The 30-day, 1-year, and end of study mortality rates were 12%, 28%, and 53%, respectively. Overall, 82(19%) patients aged <45 years died compared with 1456 (67%) patients aged > or =65 years (hazard ratio [HR], 5.07; 95% confidence interval [CI], 4.06-6.34). Male patients were more likely to die than female patients during follow-up (971 [56%] vs. 767 [49%], respectively; HR, 1.20; 95% CI, 1.13-1.37). Initial PSI classification predicted not only 30-day mortality, but also long-term postdischarge mortality, with 92 (15%) of PSI class I-II patients dying compared with 616 (82%) PSI class V patients (HR, 11.80; 95% CI, 4.70-14.70). Of 2950 patients who survived the initial CAP hospitalization, 72% were hospitalized again (median, 2 admissions over follow-up) and 16% were re-hospitalized with pneumonia. In conclusion, long-term morbidity and mortality are high following hospitalization for pneumonia and are strongly correlated with initial PSI class. This suggests that patients with pneumonia, especially those with PSI class IV and V at admission, might need better attention paid to preventive strategies and much closer follow-up due to their elevated risk of subsequent adverse events and increased health resource utilization.

Delayed Administration of Antibiotics and Mortality in Patients With Community-Acquired Pneumonia

Previous studies have demonstrated a crude association between the time to first antibiotic dose and mortality in patients with community-acquired pneumonia. We hypothesize that time to first antibiotic dose may affect mortality, particularly for patients at high risk of death, that is, patients hypoxic on presentation, patients in Pneumonia Severity Index class IV or V, and patients older than 65 years at our institution. We reviewed data from a prospectively collected database of patients with community-acquired pneumonia, excluding patients who had received antibiotics before presentation and palliative patients not receiving antibiotics. We examined time to first antibiotic dose in patients who died or had prolonged length of stay (all patients) and in specific subgroups regarded as high risk (age >65 years, Pneumonia Severity Index class IV or V, presence of hypoxia or hypotension). In 501 patients, the median time to first antibiotic dose was 2.7 hours, with 91% of patients receiving antibiotics within 8 hours. Time to first antibiotic dose was not positively associated with mortality or prolonged length of stay in any of the subgroups examined. We found evidence that patients with severe pneumonia received antibiotics earlier than other patients. Most patients at this institution already receive timely antibiotic therapy. This finding may be due to either a true lack of association, in that minor delays in antibiotic administration, where antibiotics are generally administered within 8 hours, do not affect mortality. Additionally, there may be confounding by severity, such that patients at highest risk of death received antibiotics earlier.

Risk Prediction With Procalcitonin and Clinical Rules in Community-Acquired Pneumonia

The Pneumonia Severity Index and CURB-65 predict outcomes in community-acquired pneumonia but have limitations. Procalcitonin, a biomarker of bacterial infection, may provide prognostic information in community-acquired pneumonia. Our objective is to describe the pattern of procalcitonin in community-acquired pneumonia and determine whether procalcitonin provides prognostic information beyond the Pneumonia Severity Index and CURB-65. We conducted a multicenter prospective cohort study in 28 community and teaching emergency departments. Patients presenting with a clinical and radiographic diagnosis of community-acquired pneumonia were enrolled. We stratified procalcitonin levels a priori into 4 tiers: I: less than 0.1; II: greater than 0.1 to less than 0.25; III: greater than 0.25 to less than 0.5; and IV: greater than 0.5 ng/mL. Primary outcome was 30-day mortality. One thousand six hundred fifty-one patients formed the study cohort. Procalcitonin levels were broadly spread across tiers: 32.8% (I), 21.6% (II), 10.2% (III), and 35.4% (IV). Used alone, procalcitonin had modest test characteristics: specificity (35%), sensitivity (92%), positive likelihood ratio (1.41), and negative likelihood ratio (0.22). Adding procalcitonin to the Pneumonia Severity Index in all subjects minimally improved performance. Adding procalcitonin to low-risk Pneumonia Severity Index subjects (classes I to III) provided no additional information. However, subjects in procalcitonin tier I had low 30-day mortality, regardless of clinical risk, including those in higher risk classes (1.5% versus 1.6% for those in Pneumonia Severity Index classes I to III versus classes IV/V). Among high-risk Pneumonia Severity Index subjects (classes IV/V), one quarter (126/546) were in procalcitonin tier I, and the negative likelihood ratio of procalcitonin tier I was 0.09. Procalcitonin tier I was also associated with lower burden of other adverse outcomes. Similar results were observed with CURB-65 stratification. Selective use of procalcitonin as an adjunct to existing rules may offer additional prognostic information in high-risk patients.

Predicting mortality with pneumonia severity scores: importance of model recalibration to local settings

In patients with community-acquired pneumonia (CAP) prediction rules based on individual predicted mortalities are frequently used to support decision-making for in-patient vs. outpatient management. We studied the accuracy and the need for recalibration of three risk prediction scores in a tertiary-care University hospital emergency-department setting in Switzerland. We pooled data from patients with CAP enrolled in two randomized controlled trials. We compared expected mortality from the original pneumonia severity index (PSI), CURB65 and CRB65 scores against observed mortality (calibration) and recalibrated the scores by fitting the intercept alpha and the calibration slope beta from our calibration model. Each of the original models underestimated the observed 30-day mortality of 11%, in 371 patients admitted to the emergency department with CAP (8.4%, 5.5% and 5.0% for the PSI, CURB65 and CRB65 scores, respectively). In particular, we observed a relevant mortality within the low risk classes of the original models (2.6%, 5.3%, and 3.7% for PSI classes I-III, CURB65 classes 0-1, and CRB65 class 0, respectively). Recalibration of the original risk models corrected the miscalibration. After recalibration, however, only PSI class I was sensitive enough to identify patients with a low risk (i.e. <1%) for mortality suitable for outpatient management. In our tertiary-care setting with mostly referred in-patients, CAP risk scores substantially underestimated observed mortalities misclassifying patients with relevant risks of death suitable for outpatient management. Prior to the implementation of CAP risk scores in the clinical setting, the need for recalibration and the accuracy of low-risk re-classification should be studied in order to adhere with discharge guidelines and guarantee patients' safety.

Comparing the pneumonia severity index with CURB-65 in patients admitted with community acquired pneumonia

Pneumonia severity assessment systems such as the pneumonia severity index (PSI) and CURB-65 were designed to direct appropriate site of care based on 30-d mortality. Increasingly they are being used to guide empirical antibiotic therapy and also possibly to detect patients who will require admission to the intensive care unit (ICU). We retrospectively reviewed the records of all patients admitted to our institution with confirmed community acquired pneumonia (CAP) for the 12 months from January 2002. 408 episodes were studied with an overall 30-d mortality of 15.4% and ICU admission of 10.5%. PSI classes IV/V were significantly better than CURB-65 score > or = 3 for predicting patients who died within 30 d (94% vs 62%; p < 0.001), and those that needed ICU (86% vs 61%; p = 0.01). In addition, for the patients identified as 'low risk' by PSI (classes I/II), there was only 1 death and 1 admission to an ICU compared to 8 deaths and 7 ICU admissions with CURB-65 scores of 0-1. Although easier to use, CURB-65 is neither sensitive nor specific for predicting mortality in CAP patients. Neither rule was sufficiently accurate for predicting need for an ICU, even when patients with 'not for resuscitation' orders were excluded.