Michael J. Fine

BACKGROUND: There is considerable variability in rates of hospitalization of patients with community-acquired pneumonia, in part because of physicians' uncertainty in assessing the severity of illness at presentation. METHODS: From our analysis of data on 14,199 adult inpatients with community-acquired pneumonia, we derived a prediction rule that stratifies patients into five classes with respect to the risk of death within 30 days. The rule was validated with 1991 data on 38,039 inpatients and with data on 2287 inpatients and outpatients in the Pneumonia Patient Outcomes Research Team (PORT) cohort study. The prediction rule assigns points based on age and the presence of coexisting disease, abnormal physical findings (such as a respiratory rate of > or = 30 or a temperature of > or = 40 degrees C), and abnormal laboratory findings (such as a pH <7.35, a blood urea nitrogen concentration > or = 30 mg per deciliter [11 mmol per liter] or a sodium concentration <130 mmol per liter) at presentation. RESULTS: There were no significant differences in mortality in each of the five risk classes among the three cohorts. Mortality ranged from 0.1 to 0.4 percent for class I patients (P=0.22), from 0.6 to 0.7 percent for class II (P=0.67), and from 0.9 to 2.8 percent for class III (P=0.12). Among the 1575 patients in the three lowest risk classes in the Pneumonia PORT cohort, there were only seven deaths, of which only four were pneumonia-related. The risk class was significantly associated with the risk of subsequent hospitalization among those treated as outpatients and with the use of intensive care and the number of days in the hospital among inpatients. CONCLUSIONS: The prediction rule we describe accurately identifies the patients with community-acquired pneumonia who are at low risk for death and other adverse outcomes. This prediction rule may help physicians make more rational decisions about hospitalization for patients with pneumonia.

Abstract Background This document provides evidence-based clinical practice guidelines on the management of adult patients with community-acquired pneumonia. Methods A multidisciplinary panel conducted pragmatic systematic reviews of the relevant research and applied Grading of Recommendations, Assessment, Development, and Evaluation methodology for clinical recommendations. Results The panel addressed 16 specific areas for recommendations spanning questions of diagnostic testing, determination of site of care, selection of initial empiric antibiotic therapy, and subsequent management decisions. Although some recommendations remain unchanged from the 2007 guideline, the availability of results from new therapeutic trials and epidemiological investigations led to revised recommendations for empiric treatment strategies and additional management decisions. Conclusions The panel formulated and provided the rationale for recommendations on selected diagnostic and treatment strategies for adult patients with community-acquired pneumonia.

John G. Bartlett,1 Scott F Dowell,2 Lionel A. Mandell,6 Thomas M. File, Jr.,3 Daniel M. Musher,4 and Michael J. Fine5 'Johns Hopkins University School of Medicine, Baltimore, Maryland, 2Centers for Disease Control and Prevention, Atlanta, Georgia, 3Northeastern Ohio Universities College of Medicine, Cleveland, Ohio, 4Baylor College of Medicine and Veterans Affairs Medical Center, Houston, Texas, and 5University of Pittsburgh, Pennsylvania, USA; and 6McMaster University, Toronto, Canada

OBJECTIVE: To systematically review the medical literature on the prognosis and outcomes of patients with community-acquired pneumonia (CAP). DATA SOURCES: A MEDLINE literature search of English-language articles involving human subjects and manual reviews of article bibliographies were used to identify studies of prognosis in CAP. STUDY SELECTION: Review of 4573 citations revealed 122 articles (127 unique study cohorts) that reported medical outcomes in adults with CAP. DATA EXTRACTION: Qualitative assessments of studies' patient populations, designs, and patient outcomes were performed. Summary univariate odds ratios (ORs) and rate differences (RDs) and their associated 95% confidence intervals (CIs) were computed to estimate a summary effect size for the association of prognostic factors and mortality. DATA SYNTHESIS: The overall mortality for the 33,148 patients in all 127 study cohorts was 13.7%, ranging from 5.1% for the 2097 hospitalized and ambulatory patients (in six study cohorts) to 36.5% for the 788 intensive care unit patients (in 13 cohorts). Mortality varied by pneumonia etiology, ranging from less than 2% to greater than 30%. Eleven prognostic factors were significantly associated with mortality using both summary ORs and RDs: male sex (OR = 1.3; 95% CI, 1.2 to 1.4), pleuritic chest pain (OR = 0.5; 95% CI, 0.3 to 0.8), hypothermia (OR = 5.0; 95% CI, 2.4 to 10.4), systolic hypotension (OR = 4.8; 95% CI, 2.8 to 8.3), tachypnea (OR = 2.9; 95% CI, 1.7 to 4.9), diabetes mellitus (OR = 1.3; 95% CI, 1.1 to 1.5), neoplastic disease (OR = 2.8; 95% CI, 2.4 to 3.1), neurologic disease (OR = 4.6; 95% CI, 2.3 to 8.9), bacteremia (OR = 2.8; 95% CI, 2.3 to 3.6), leukopenia (OR = 2.5, 95% CI, 1.6 to 3.7), and multilobar radiographic pulmonary infiltrate (OR = 3.1; 95% CI, 1.9 to 5.1). Assessments of other clinically relevant medical outcomes such as morbid complications (41 cohorts), symptoms resolution (seven cohorts), return to work or usual activities (five cohorts), or functional status (one cohort) were infrequently performed. CONCLUSIONS: Mortality for patients hospitalized with CAP was high and was associated with characteristics of the study cohort, pneumonia etiology, and a variety of prognostic factors. Generalization of these findings to all patients with CAP should be made with caution because of insufficient published information on medical outcomes other than mortality in ambulatory patients.